3,002 results on '"ANIMAL populations"'
Search Results
2. Melanism in Polymorphic Terrestrial Snakes: A Meta‐Analysis and Systematic Review.
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Sahlean, Tiberiu Constantin, Martin, Ryan A., Spaseni, Petronel, Gherghel, Iulian, and Strugariu, Alexandru
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ANIMAL diversity , *POLYMORPHISM (Zoology) , *ANIMAL populations , *CLIMATE change , *MELANISM - Abstract
ABSTRACT Background and Aim Location Taxon Results Main Conclusions Colour polymorphic populations constitute excellent model systems for testing ecological and evolutionary hypotheses, as alternate colourations are associated with differences in various biological, behavioural and life‐history traits. Melanism is the most common and most obvious form of polymorphism. In reptiles in general (and snakes in particular), thermal melanism has been a popular hypothesis used to explain the appearance of black individuals. It suggests that a trade‐off exists between superior thermoregulation and reduced protection through the loss of crypsis. Surprisingly, despite the growing body of literature available, to date, there are only two qualitative reviews on the evolutionary significance of melanism in reptiles and no quantitative synthesis. We conducted the first systematic review and meta‐analysis summarising the current knowledge on melanism in polymorphic terrestrial snakes and synthesised the evidence for an adaptive advantage of the melanistic morph.Northern Hemisphere.Polymorphic terrestrial snakes.Mean prevalence of melanism is 31% with no significant differences between species. Annual precipitation was a significant moderator of melanism prevalence. Our results revealed no significant differences in odds ratios of melanism between sexes or in mean body size.Environmental plasticity can be considered the primary cause of melanism, possibly as a result of seasonal climatic variations, a result corroborated by the formal meta‐analysis conducted. Conclusions from the meta‐analysis are that melanism in snakes follows Gloger's rule, as is the case in birds and mammals, and as opposed to the thermal melanism hypothesis. Further, our findings do not lend support for other predictions from the thermal melanism hypothesis, such as skewed frequency of melanistics in favour of males or females, or larger body sizes in black individuals. Our results hold implications for the future diversity of animal populations, as climate change is predicted to decrease the degree of colour variation. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Detection and prevalence of a novel Bandavirus related to Guertu virus in Amblyomma gemma ticks and human populations in Isiolo County, Kenya.
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Koka, Hellen, Langat, Solomon, Oyola, Samuel, Cherop, Faith, Rotich, Gilbert, Mutisya, James, Ofula, Victor, Limbaso, Konongoi, Ongus, Juliette R., Lutomiah, Joel, and Sang, Rosemary
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NUCLEOTIDE sequencing , *AMINO acid sequence , *VIRUS isolation , *ANIMAL populations , *AMBLYOMMA - Abstract
Introduction: Emerging tick-borne viruses of medical and veterinary importance are increasingly being reported globally. This resurgence emphasizes the need for sustained surveillance to provide insights into tick-borne viral diversity and associated potential public health risks. We report on a virus tentatively designated Kinna virus (KIV) in the family Phenuiviridae and genus Bandavirus. The virus was isolated from a pool of Amblyomma gemma ticks from Kinna in Isiolo County, Kenya. High throughput sequencing of the virus isolate revealed close relatedness to the Guertu virus. The virus genome is consistent with the described genomes of other members of the genus Bandavirus, with nucleotides lengths of 6403, 3332 and 1752 in the Large (L), Medium (M) and Small (S) segments respectively. Phylogenetic analysis showed that the virus clustered with Guertu virus although it formed a distinct and well supported branch. The RdRp amino acid sequence had a 93.3% identity to that of Guertu virus, an indication that the virus is possibly novel. Neutralizing antibodies were detected in 125 (38.6%, 95% CI 33.3–44.1%) of the human sera from the communities in this region. In vivo experiments showed that the virus was lethal to mice with death occurring 6–9 days post-infection. The virus infected mammalian cells (Vero cells) but had reduced infectivity in the mosquito cell line (C636) tested. Conclusion: Isolation of this novel virus with the potential to cause disease in human and animal populations necessitates the need to evaluate its public health significance and contribution to disease burden in the affected regions. This also points to the need for continuous monitoring of vector and human populations in high-risk ecosystems to update pathogen diversity. [ABSTRACT FROM AUTHOR]
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- 2024
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4. The genetic relationship between human and pet isolates: a core genome multilocus sequence analysis of multidrug-resistant bacteria.
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Genath, Antonia, Hackmann, Carolin, Denkel, Luisa, Weber, Anna, Maechler, Friederike, Kola, Axel, Schwarz, Stefan, Gastmeier, Petra, and Leistner, Rasmus
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METHICILLIN-resistant staphylococcus aureus , *ESCHERICHIA coli , *MULTIDRUG resistance , *ANIMAL populations , *PETS , *ENTEROCOCCUS - Abstract
Introduction: The global increase of multidrug-resistant organisms (MDROs) is one of the most urgent public health threats affecting both humans and animals. The One Health concept emphasizes the interconnectedness of human, animal and environmental health and highlights the need for integrated approaches to combat antimicrobial resistance (AMR). Although the sharing of environments and antimicrobial agents between companion animals and humans poses a risk for MDRO transmission, companion animals have been studied to a lesser extent than livestock animals. This study therefore used core genome multilocus sequence typing (cgMLST) to investigate the genetic relationships and putative transmission of MDROs between humans and pets. Methods: This descriptive integrated typing study included 252 human isolates, 53 dog isolates and 10 cat isolates collected from 2019 to 2022 at the Charité University Hospital in Berlin, Germany. CgMLST was performed to characterize methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and multidrug-resistant gram-negative bacteria. The genetic diversity of the MDROs of the different host populations was determined and compared based on sequence type and core genome complex type. Results: Within this study the majority of samples from pets and humans was genetically distinct. However, for some isolates, the number of allelic differences identified by cgMLST was low. Two cases of putative household transmission or shared source of VR E. faecium and MDR E. coli between humans and pets were documented. Conclusions: The interaction between humans and their pets appears to play a minor role in the spread of the MDROs studied. However, further research is needed. This study emphasizes the importance of comprehensive molecular surveillance and a multidisciplinary One Health approach to understand and contain the spread of MDROs in human and animal populations. Trial Registration: The study is registered with the German Clinical Trials Register (DRKS00030009). [ABSTRACT FROM AUTHOR]
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- 2024
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5. Successful citizen science tools to monitor animal populations require innovation and communication: SealSpotter as a case study.
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Puskic, Peter S., Holmberg, Ross, and McIntosh, Rebecca R.
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DRONE aircraft ,ANIMAL populations ,CITIZEN science ,ONLINE education ,MARINE mammals - Abstract
In rapidly changing ocean systems, there is a dual need to engage and educate community members and carry out rapid data acquisition. There is a body of evidence to support community or citizen science projects as successful vehicles for achieving these goals, with a particular need to increase global ocean literacy. The online SealSpotter program is a citizen science initiative aimed at monitoring trends in Australian fur seal (Arctocephalus pusillus doriferus) populations and connecting people to the marine environment. Here we present the findings of five years of monitoring of fur seals using drone surveys counted by citizen scientists via SealSpotter. Over five years, global participants from 23 countries were engaged in counting seals with a focus on the annual breeding season and pup abundance, with an average of 13,479 images and 171,137 seals counted per year. SealSpotter participants presented more conservative (lower) counts than expert counts, however both groups detected similar trends in abundance, emphasizing success of the project aims that included obtaining a precise index of pup abundance; ultimately a more achievable goal than accuracy due to the difficulties in measuring absolute abundance. We reflect on SealSpotter's accomplishments and highlight the potential for marine citizen science programs as important tools for addressing global ocean literacy needs. The SealSpotter program contributes to our understanding of marine ecosystems through a simple but effective citizen science program. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Collective intelligence facilitates emergent resource partitioning through frequency-dependent learning.
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Ogino, Mina and Farine, Damien R.
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ANIMAL populations , *SWARM intelligence , *SHORT-term memory , *ENRICHED foods , *FOOD chains - Abstract
Deciding where to forage must not only account for variations in habitat quality but also where others might forage. Recent studies have suggested that when individuals remember recent foraging outcomes, negative frequency-dependent learning can allow them to avoid resources exploited by others (indirect competition). This process can drive the emergence of consistent differences in resource use (resource partitioning) at the population level. However, indirect cues of competition can be difficult for individuals to sense. Here, we propose that information pooling through collective decision-making—i.e. collective intelligence—can allow populations of group-living animals to more effectively partition resources relative to populations of solitary animals. We test this hypothesis by simulating (i) individuals preferring to forage where they were recently successful and (ii) cohesive groups that choose one resource using a majority rule. While solitary animals can partially avoid indirect competition through negative frequency-dependent learning, resource partitioning is more likely to emerge in populations of group-living animals. Populations of larger groups also better partition resources than populations of smaller groups, especially in environments with more choices. Our results give insight into the value of long- versus short-term memory, home range sizes and the evolution of specialization, optimal group sizes and territoriality. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'. [ABSTRACT FROM AUTHOR]
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- 2024
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7. International overview of sea turtle fibropapillomatosis: a survey of expert opinions and trends.
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Whilde, Jenny, Mashkour, Narges, Koda, Samantha A., Eastman, Catherine B., Thompson, Drew, Burkhalter, Brooke, Frandsen, Hilary R., Page, Annie, Blackburn, Nicholas B., Jones, Karina, Ariel, Ellen, Dupont, Sophie M., Wood, Lawrence, and Duffy, David J.
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SEA turtles ,GREEN turtle ,DRUG discovery ,ANIMAL populations ,VETERINARY epidemiology - Abstract
Introduction: Marine environments offer a wealth of opportunities to improve understanding and treatment options for cancers, through insights into a range of fields from drug discovery to mechanistic insights. By applying One Health principles the knowledge obtained can benefit both human and animal populations, including marine species suffering from cancer. One such species is green sea turtles (Chelonia mydas), which are under threat from fibropapillomatosis (FP), an epizootic tumor disease (animal epidemic) that continues to spread and increase in prevalence globally. In order to effectively address this epizootic, a more thorough understanding is required of the prevalence of the disease and the approaches to treating afflicted turtles. Methods: To identify knowledge gaps and assess future needs, we conducted a survey of sea turtle FP experts. The survey consisted of 47 questions designed to assess general perceptions of FP, the areas where more information is needed, local FP trends, the disease status, and mitigation needs, and was voluntarily completed by 44 experts across a broad geographic range. Results: Over 70% of respondents both recognized FP as a cancerous panzootic disease, and reported that FP is increasing in prevalence. They report several factors contributing to this increase. Nearly all of the respondents reported that FP research, patient treatment and rehabilitation required more funding in their area, and reported inadequate facilities and capacity for dealing with FP patients. Treatment approaches varied: just over 70% of the medical experts that responded surgically remove FP tumors, either using laser or scalpel. Just under half of respondents use anti-cancer drugs in their treatment of FP. Internal tumors were reported as justification for euthanasia by 61.5% of respondents, and 30.8% reported severe external tumors to be sufficient grounds for euthanasia. Most medical respondents (93.3%) routinely perform necropsy on deceased or euthanized FP-afflicted turtles. Over 80% of respondents considered large-scale multidisciplinary collaboration 'extremely important' for advancing the field of FP research. Discussion: The survey responses provide a valuable insight into the current status of FP in sea turtles, FP treatment, rehabilitation and research, and help to identify critical FP-related areas most in need of attention. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Survey of Gastro-intestinal and Ectoparasites of Games in Ogun State, Nigeria.
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Akande, F. A., Olaniyan, K. O., Osifade, O. A., and Takeet, M. I.
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BROWN dog tick , *GAME & game-birds , *DISEASE vectors , *ANIMAL populations , *GASTROINTESTINAL system , *HELMINTHS - Abstract
Games are wild animals often referred to as "bushmeat" when killed, primarily for personal consumption and/or monetary exchange. Parasites of games, such as protozoa, helminths, and ectoparasites, have not always been reported; however, they are essentially zoonotic, thereby putting animal and human populations at risk whenever present. The lack of information on these parasites, as well as the danger of their presence, necessitated this study to provide baseline data regarding the area, as well as information on possible zoonosis at the human-animalenvironment interface. Physical examination was conducted on animals brought from hunting sprees to the "bushmeat" market during which all visible ectoparasites were harvested and were kept in 70% ethanol, samples were harvested from portions of the gastrointestinal tract of freshly killed games and transferred into well-labelled containers by ligation of each portion to assay for Gastrointestinal Parasites (GIP). The samples were analysed using centrifugal flotation for GIP and morphology for ectoparasite identification. Grasscutter (Thryonomys swinderianus) and Antelope (Maxwell's duiker, Philantomba maxwellii) were examined during the study period, with 90.9% and 66.7% mixed and 9% and 25% mono infections, respectively. GIP eggs were Strongyle (36.4%, 25%), Trichuris (45.5%, 16.7%), Haemonchus (18.2%, 16.7%), Strongyloides (18.2%, 16.7%), Ascaridia (9%, 16.7%), and Eimeria (63.6%, 75%) in Grasscutter and Antelope, respectively, whereas Moniezia (25%), Taenia (16,7%), and Hookworm (18.2%) occurred only in the antelope, with the highest infection in the ileum and colon (63.6%), and rectum (83%) of Grasscutter and antelope, respectively. Four genera of ticks were identified: Amblyomma (41%), Rhipicephalus (Boophilus) microplus (20.5%), Rhipicephalus sanguineus (17.9%), Haemaphysalis (12.8%), and Hyalomma (7.7%). The presence of zoonotic GIP and ticks, which are known vectors of various diseases, calls for further studies, education, and awareness among the hunting community. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Resurrecting plant–animal interactions in the Caribbean can benefit large‐fruited plants.
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Kim, Seokmin, Lautenschlager, Laís, Tarazona‐Tubens, Fabio L., Abels, Jason, Lloret, Michael, Park, Ty, Malcolm‐Parker, Ayrimah, Galetti, Mauro, and Searcy, Christopher
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SEED dispersal by animals , *PLANT dispersal , *PLANT size , *SEED dispersal , *ANIMAL populations , *GERMINATION - Abstract
Many plants benefit from seed dispersal by frugivorous animals. This mutualistic interaction depends largely on interaction‐relevant matching of functional traits (i.e. fruit size of plants and gape size of frugivores). With declines in large‐bodied animal populations, it is likely that fruit–frugivore interactions have eroded, leading to the loss of seed dispersal of large‐fruited plants. Such erosion could be especially evident in vulnerable island ecosystems such as those in the Caribbean, where most large‐bodied frugivore populations have collapsed due to human activities. Here, we aim to understand the consequences of this decline by first quantifying gaps in frugivory function between common, smaller frugivores (birds, smaller reptiles, and bats) and rarer or regionally extinct, larger reptiles (Cyclura spp. and Chelonoidis spp.) in the Caribbean archipelagos. We then assess the benefits of reestablishing these interactions by determining the effects of large reptile ingestion on seed germination for 10 fruiting species, representing a range of fruit sizes, native to the Caribbean. We found that there are significant gaps in frugivory function, with smaller frugivores having many times smaller mean gape sizes than larger reptiles. Furthermore, we found that most fruiting species used in this study could germinate after being consumed by large reptiles, with two species having their germination speed significantly accelerated post‐ingestion. These results indicate that fruiting plants could benefit from reestablishing frugivorous interactions between larger reptiles and fruiting plants. Given the existing gap in frugivory function, additional attention should be given to the possibility of rewilding defaunated islands to restore plant–frugivore networks. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Low rate of population establishment of a freshwater invertebrate (Gammarus lacustris) in experimental conservation translocations.
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Fitzpatrick, Megan J., Anteau, Michael J., Isaacson, Carl W., Carleen, Jake D., Keith, Breanna R., Thoele, Barry, Bieganek, Michael, Taylor, Alaina A., and Larson, Danelle M.
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FRESHWATER biodiversity , *FRESHWATER invertebrates , *WILDLIFE resources , *WATER chemistry , *GAMMARUS , *AMPHIPODA , *WETLANDS , *ANIMAL populations - Abstract
Conservation translocations may be a useful tool for the restoration of declining freshwater invertebrates, but they are poorly represented in the literature. We conducted a before‐after/control‐impact (BACI) experiment to test the efficacy of conservation translocation for re‐establishing abundant populations of the amphipod Gammarus lacustris, a declining species and wildlife food resource in depressional wetlands in the upper Midwest of the United States of America. Each study site (n = 19) contained at least one treatment wetland receiving translocated G. lacustris from a local donor and one control wetland. We selected study wetlands based on a suite of wetland characteristics and randomly assigned recipient versus control treatment. Gammarus lacustris was detected post‐translocation at only 2 of 22 recipient wetlands (1 of 19 sites). Overall, there was a statistical increase in G. lacustris density in recipient wetlands compared to controls; however, the results were of minimal biological significance due to being driven by a single site with low G. lacustris densities. Accordingly, our results suggest that future conservation translocations of amphipods might be successful if limited to recently restored wetlands or informed by a more complex habitat suitability model to differentiate dispersal limitations from habitat limitations. To develop such a model would involve identifying the fewest, most influential physical and biological factors (e.g. wetland size/structure, fish, aquatic vegetation, and water chemistry) from the numerous inter‐related factors that correlate with the abundance of naturally occurring G. lacustris; candidate wetlands to receive amphipods would be those for which the model predicts abundant G. lacustris but in which they do not presently occur. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Feline Encounters Down Under: Investigating the Activity of Cats and Native Wildlife at Sydney's North Head.
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Kennedy, Brooke P. A., Clemann, Anna, and Ma, Gemma C.
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WILDLIFE conservation , *NATIVE species , *COLONIES (Biology) , *IMAGE analysis , *RESIDENTIAL areas , *CATS , *ANIMAL populations - Abstract
Simple Summary: Cats are a common sight across Australia, freely roaming not only through urban areas but also within natural habitats, including protected areas like national parks. This unrestricted movement raises concerns due to potential impacts on native wildlife populations. North Head, Manly, located in New South Wales, serves as a prime example, boasting a rich biodiversity that includes endangered populations of Long-nosed Bandicoots and Little Penguins. Recent observations by wildlife officers within Sydney Harbour National Park and the North Head Sanctuary highlighted the presence of cats, prompting a deeper investigation into their spatial and temporal distribution. Cameras were installed across the headland over a five-week period to capture cat and native fauna activity. Cats were frequently observed at the interface with the urban area of Manly. Moreover, cat activity primarily occurred during the night, coinciding with periods of heightened native mammal activity. These findings underscore the potential for direct and indirect interactions between cats and native wildlife within the headland, with implications for species conservation efforts. This study emphasises the importance of implementing proactive management strategies to mitigate the potential impact of feline predation on local biodiversity while also highlighting the need for further research in this area. Cats (Felis catus) are widespread across Australia, including within natural and protected areas, and in many areas, cats, including owned domestic cats, are not restricted in where or when they can roam. In Australia, cats have contributed to the decline of many native species and continue to be a problem for governments. North Head, Manly, is home to an endangered population of Long-nosed Bandicoot (Perameles nasuta) and the only mainland breeding colony of Little Penguin (Eudyptula minor) in New South Wales (NSW). Camera traps were installed for a 5-week period across North Head to determine the spatial and temporal distribution of cat activity. As well as capturing instances of cats, the cameras detected native animals such as birds, possums, Long-nosed Bandicoots and other small mammals. An analysis of the camera images showed cats could be found within protected areas of the headland (where cats are prohibited) and along the boundary with the adjacent suburban area of Manly. Cats were mostly detected during the night. There were high occurrences of overlap between cats and Long-nosed Bandicoots (Dhat 0.82), possums (Dhat 0.88) and other small mammals (Dhat 0.67). These findings indicate that cats are active across the Manly headland at the same time as native animals, both within protected areas where cats are prohibited and in adjacent residential areas, and this could have implications for these populations. [ABSTRACT FROM AUTHOR]
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- 2024
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12. The Determination of the Prohibited Herbicide 4,6-Dinitro-Ortho-Cresol (DNOC) in Poisoned Domestic and Wild Animals in Italy.
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Rocchi, Rachele, Tinelli, Antonella, Gatti, Giuseppe, Badagliacca, Pietro, Cocco, Antonio, Cantelmi, Maria Chiara, Damiano, Antonella, Scortichini, Giampiero, Merola, Carmine, and Petrini, Antonio
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ENVIRONMENTAL health , *POISONS , *ANIMAL health , *ANIMAL populations , *RED fox - Abstract
Simple Summary: This study reported for the first time in Italy the determination of 4,6-dinitro-ortho-cresol (DNOC) in the baits and gastric contents of poisoned animals. The determination of DNOC was achieved by using gas chromatography coupled to mass spectrometry (GC-MS) with both full-scan and selected ion monitoring (SIM) modes (ion m/z values 198, 121, and 105). This study reports the determination of DNOC in the baits and gastric contents of poisoned dogs and wild canids collected in the Abruzzo region between 2014 and 2022. A total of 663 samples of the baits and carcasses of domestic and wild animals were analyzed for the determination of DNOC through GC-MS. DNOC was found to be present in 58 cases from 663 analyzed samples, with 49 poison baits and nine gastric content samples from dogs and red foxes. This study confirms for the first time that the banned pesticide DNOC still poisons both domestic and wild animals in the Abruzzo region. It should be considered that this study was carried out on a population of animals from a regional geographical area, and more detailed country-wide studies need to be carried out to obtain the incidence of poisoning from this herbicide in Italy. Furthermore, these findings emphasize the importance of considering this chemical in differential diagnosis during toxicological investigations of animal poisoning. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Evaluation of Population Management Based on Trap–Neuter–Return and Trap–Neuter–Adoption Practices in a Free-Roaming Cat Colony in the Federal District, Brazil.
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Junqueira, Ana Nira Nunes and Galera, Paula Diniz
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COLONIES (Biology) , *ANIMAL welfare , *ANIMAL populations , *DOMESTIC animals , *ENVIRONMENTAL management - Abstract
Simple Summary: Feline colonies cause various environmental, public health, and animal welfare problems, highlighting the importance of adequate management in promoting the One Health concept. This study evaluated the trap–neuter–return approach as a population management method for a colony of 157 animals. Following interventions conducted over 18 months, there was a 47.8% reduction in colony size, and 98.8% of the animals were sterilized. Adoption played an important role in reducing population growth. This strategy prevented kitten birth, fostered stronger bonds between caregivers and animals, and protected against death, disappearance, and abandonment. The study's results will aid environmental and health management planning and decision-making, benefiting society, animals, and the environment. Overpopulation of domestic animals leads to various problems, such as the formation of feline colonies. Population management methods for these colonies have been studied previously; however, no scientific consensus has been reached. This study evaluated the use of trap–neuter–return (TNR) in a free-roaming cat colony in Brazil's Federal District. The study was conducted over 18 months and involved 157 cats that had not previously been managed. The experiment had three parts: recognition and preparation, TNR intervention, and monitoring. The results showed a 47.8% reduction in colony size. Additionally, 98.8% of the animals were sterilized. The adoption, death, disappearance, abandonment, and immigration rates were 19.7%, 14.0%, 14.0%, 7.6%, and 4.5%, respectively. The TNR experiment conducted in the proposed manner, which included detailed pre-planning, mass sterilization, active management, continuous monitoring, and educational actions, proved to be efficient and humane. However, guidelines aimed at managing animal populations, promoting adoption, preventing abandonment, and educating people about responsible pet ownership are essential for achieving sustainable results. [ABSTRACT FROM AUTHOR]
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- 2024
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14. CO2 and acidification effects on larval frog immune function, growth, and survival.
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Rosales, Alayna M., Wilcoxen, Travis E., and Marino Jr, John A.
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PHYSIOLOGY , *AQUATIC animals , *ENVIRONMENTAL chemistry , *FRESHWATER animals , *IMMUNOGLOBULIN M , *ANIMAL populations , *BULLFROG , *TADPOLES - Abstract
Variation in environmental chemistry affects animal health and demographics. For instance, acidification of aquatic ecosystems (e.g., due to acid rain) can have consequences for organismal fitness. Elevated atmospheric concentrations of CO2, which reacts with water to produce carbonic acid, may affect aquatic animal physiology in multiple ways, including via reductions in pH. Such impacts have been assessed to a large extent in marine systems. Similar effects are also likely occurring in freshwater ecosystems but are relatively understudied. The goal of this project was to determine how changes in pH and CO2 concentrations influence traits and survival of animals in freshwater systems, using larval American Bullfrogs (Lithobates catesbeianus (also known as Rana catesbeiana) [Shaw, 1802]) as a model. We hypothesized that elevated CO2 concentrations and reduced pH negatively affect larval frog immune function, growth, and survival, which we tested in a laboratory aquarium experiment. Over the 27-d experiment, tadpoles were exposed to 4 treatments: 1) near-neutral pH and no gas addition (mean ± SE pH = 7.17 ± 0.05), 2) CO2 gas sparged into aquariums (pH = 5.32 ± 0.04), 3) acidified water without gas addition (pH = 6.29 ± 0.08), and 4) ambient air sparged into aquariums (control for effects of gas addition) at near-neutral pH (pH = 7.46 ± 0.03). We measured tadpole innate immune response, growth, and survival. Results from the experiment partially supported our hypothesis, with lower immune function in tadpoles exposed to acidified water or elevated CO2 compared with the control treatments and lower final mass and survival under elevated CO2. These findings motivate additional research on pH and CO2 effects on freshwater animals and suggest that increased environmental acidity and elevated CO2 can lead to negative impacts, which could contribute to reductions in wildlife health and population declines in light of ongoing environmental changes. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Inbreeding and cognition in wild populations: a relationship that remains unnoticed.
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Gavriilidi, Ioanna and Van Linden, Lisa
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ANIMAL populations , *ANIMAL cognition , *COGNITIVE ability , *ECOLOGICAL disturbances , *COGNITION disorders - Abstract
Anthropogenic activities are causing a steep decline of wildlife populations. Increased inbreeding in shrinking populations can substantially curb individual fitness and population viability. One potentially important but largely ignored component of inbreeding depression may be cognitive decline. Cognition affects an animal's capacity to respond to environmental disturbance, which, in the face of global change, may make the difference between persistence and extinction. While the effects of inbreeding on cognitive performance have been relatively well documented in humans, they remain largely unexplored in natural populations. Here we review the current (limited) knowledge on whether and how inbreeding impinges on animals' cognitive abilities. Insights into the relationship between inbreeding and cognition could prove valuable not only for comprehending the development and evolution of cognition but also for conservation. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Correlating male white‐tailed deer antler size with female body mass across multiple spatial scales.
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Turner, Mark A., Harper, Craig A., Strickland, Bronson K., Lashley, Marcus A., Wilber, Mark Q., and McKinley, William
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BODY size , *ANIMAL populations , *ANTLERS , *UNGULATES , *ADULTS , *WHITE-tailed deer - Abstract
Managers use morphometric data collected from harvested animals as indicators of nutritional condition. Antler or horn size often are considered in ungulates, but there are problems associated with biased and limited harvest data available from male animals in many populations. Adult female body mass also may be collected, but little information exists on how male antler size scales with female body mass. We evaluated the relationship between property‐specific mature male white‐tailed deer (Odocoileus virginianus) antler size and adult female body mass from harvest data collected at 2 spatial scales. Regression predicted a 4.4‐cm increase in average mature male antler size for every 1‐kg increase in female body mass from 31 properties across the eastern United States, 2015–2023. Adult female mass explained 64% of the variation in mature antler size, and including latitude as a covariate did not improve model fit. When we considered data from 174 properties in Mississippi, USA, 1991–1994, we predicted a 4.7‐cm increase in average mature male antler size for every 1‐kg increase in adult female body mass. Including soil resource region in the Mississippi model explained 48% of the variation in mature male antler size by accounting for differences in average sizes across regions. Our results indicate average female body mass correlates with mature male antler size at multiple spatial scales. We recommend managers collect body mass and age from harvested female deer, as female mass represents a useful metric to track management progress and predict changes in antler size. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Nutrient dilution and the future of herbivore populations.
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Kaspari, Michael and Welti, Ellen A.R.
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NUTRIENT density , *ANIMAL populations , *TROPICAL ecosystems , *PLANT cells & tissues , *CARBON dioxide - Abstract
Global declines in animal populations suggest global causes. Herbivores are uniquely vulnerable to declines in the nutrient density of the plants they consume. CO 2 pollution is a global agent of nutrient dilution: the impoverishment of plant tissue, bite for bite, of the elements essential for herbivore survival. As plants assimilate higher levels of CO 2 , nutrient dilution can create flammable 'green deserts' of low-quality food for herbivores already limited by elements from nitrogen to sodium to zinc. We posit that nutrient dilution is a key driver – rich in testable predictions – of global declines in herbivore abundance. Its impact should be highest in productive and/or nutrient-poor ecosystems like tropical forests and the open oceans. It is reversed by fertilization. It acts regardless of habitat size or pesticide use. It thus complements these and other agents of herbivore decline. Nutrient dilution (ND) – the decrease in the concentration of nutritional elements in plant tissue – arises from an increase in the mass of carbohydrates and/or a decrease in the 20+ essential elements. Increasing CO 2 levels and its promotion of biomass are linked to nutrient dilution. We build a case for nutrient dilution as a key driver in global declines in herbivore abundance. Herbivores must build element-rich animal tissue from nutrient-poor plant tissue, and their abundance commonly increases with fertilization of both macro- and micronutrients. We predict the global impacts of nutrient dilution will be magnified in some of Earth's most biodiverse, highly productive, and/or nutrient-poor ecosystems and should favor specific traits of herbivores, including sap-feeding and ruminant microbiomes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
18. Diet and seed dispersal of bearded capuchin monkeys (Sapajus libidinosus) in Brasilia National Park.
- Author
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de Albuquerque Teixeira, Samara, Souza‐Alves, João Pedro, Bezerra de Melo, Risolândia, Henriques Tavares, Maria Clotilde, and Haugaasen, Torbjørn
- Subjects
- *
WILDLIFE conservation , *CAPUCHIN monkeys , *SEED dispersal , *FECES , *ANIMAL populations , *GERMINATION - Abstract
The dietary ecology of a species can provide information on habitat requirements, food resources, and trophic interactions, important to guide conservation efforts of wildlife populations in endangered habitats. In this study, we investigated the dietary ecology of bearded capuchin monkeys (Sapajus libidinosus) in Brasilia National Park, in the endangered Cerrado biome of central Brazil. To obtain diet composition and evaluate the role of these primates as seed dispersers of local tree species, fecal sample collections and feeding observations were performed for a 7‐month period. To determine whether seeds germinated better after passing through a primate gut, we conducted germination trials with (i) pulped seeds from trees, (ii) depulped seeds from trees, (iii) seeds from feces planted with feces, and (iv) seeds from feces planted without feces. During experimental procedures, 7308 seeds from 8 families and 10 species were planted. We found that S. libidinosus spent more time feeding on fruits than on any other food item and the diet consisted of 33 plant species from 21 families. However, 20% of their diet consisted of anthropic food. Most seeds planted with feces germinated faster compared to seeds in other experimental treatments, suggesting that passing through the gut and being deposited with fecal material is advantageous. The bearded capuchins also defecated many medium‐ (5 species) and large‐sized (2 species) seeds that may be inaccessible to smaller arboreal frugivores. The results obtained emphasize the important role of bearded capuchins as seed dispersers for the maintenance and conservation of the endangered Cerrado biome. Highlights: Bearded capuchin monkeys are important dispersers of medium‐ and large‐sized seeds in the Cerrado.Seeds having passed through a primate gut and being deposited in feces germinated faster than other seeds.A reduction in primate populations may negatively affect seed dispersal and recruitment of local plant species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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19. Sample Size for Estimating Disease Prevalence in Free-Ranging Wildlife Populations: A Bayesian Modeling Approach.
- Author
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Booth, James G., Hanley, Brenda J., Hodel, Florian H., Jennelle, Christopher S., Guinness, Joseph, Them, Cara E., Mitchell, Corey I., Ahmed, Md Sohel, and Schuler, Krysten L.
- Subjects
- *
ANIMAL populations , *WILDLIFE diseases , *DISEASE prevalence , *SAMPLE size (Statistics) , *COMPUTER simulation - Abstract
A two-parameter model and a Bayesian statistical framework are proposed for estimating prevalence and determining sample size requirements for detecting disease in free-ranging wildlife. Current approaches tend to rely on random (ideal) sampling conditions or on highly specialized computer simulations. The model-based approach presented here can accommodate a range of different sampling schemes and allows for complications that arise in the free-ranging wildlife setting including the natural clustering of individuals on the landscape and correlation in disease status from transmission among individuals. Correlation between individuals and the sampling scheme have important consequences for the sample size requirements. Specifically, high within cluster correlations in disease status can reduce sample size requirements by reducing the effective population size. However, disproportionate sampling of small subsets of subjects from the greater target population, combined with high correlation of disease status, tends to inflate sample size requirements, because it increases the likelihood of sampling multiple animals within the same highly correlated clusters, resulting in little additional information gleaned from those samples. Our results are consistent with those generated using both previously established approaches and extend their ability to adapt to additional biological, epidemiological, or societal sampling complications specific to wildlife health. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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20. Accommodating False Positives Within Acoustic Spatial Capture–Recapture, with Variable Source Levels, Noisy Bearings and an Inhomogeneous Spatial Density.
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Petersma, Felix T., Thomas, Len, Thode, Aaron M., Harris, Danielle, Marques, Tiago A., Cheoo, Gisela V., and Kim, Katherine H.
- Subjects
- *
ANIMAL populations , *SENSOR arrays , *ZOOLOGICAL surveys , *MEASUREMENT errors , *BIOACOUSTICS - Abstract
Passive acoustic monitoring is a promising method for surveying wildlife populations that are easier to detect acoustically than visually. When animal vocalisations can be uniquely identified on an array of sensors, the potential exists to estimate population density through acoustic spatial capture–recapture (ASCR). However, sound classification is imperfect, and in some situations, a high proportion of sounds detected on just a single sensor ('singletons') are not from the target species. We present a case study of bowhead whale calls (Baleana mysticetus) collected in the Beaufort Sea in 2010 containing such false positives. We propose a novel extension of ASCR that is robust to false positives by truncating singletons and conditioning on calls being detected by at least two sensors. We allow for individual-level detection heterogeneity through modelling a variable sound source level, model inhomogeneous call spatial density, and include bearings with varying measurement error. We show via simulation that the method produces near-unbiased estimates when correctly specified. Ignoring source-level variation resulted in a strong negative bias, while ignoring inhomogeneous density resulted in severe positive bias. The case study analysis indicated a band of higher call density approximately 30 km from shore; 59.8% of singletons were estimated to have been false positives. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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21. Evaluating the effectiveness of joint species distribution modeling for freshwater fish communities within large watersheds.
- Author
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McLaughlin, Paul, Krause, Kevin, Maloney, Kelly, Woods, Taylor, and Wagner, Tyler
- Subjects
- *
ENDANGERED species , *WILDLIFE conservation , *SPECIES distribution , *NUMBERS of species , *FISH communities , *ANIMAL populations - Abstract
Accurately predicting species' distributions is critical for the management and conservation of fish and wildlife populations. Joint species distribution models (JSDMs) account for dependencies between species often ignored by traditional species distribution models. We evaluated how a JSDM approach could improve predictive strength for stream fish communities within large watersheds (the Chesapeake Bay Watershed, USA), using a cross-validation study of JSDMs fit to data from over 50 species. Our results suggest that conditional predictions from JSDMs have the potential to make large improvements in predictive accuracy for many species, particularly for more generalist species where single species models may not perform well. For some species there was no added explanatory effect from conditional information, most of which already exhibited strong marginal predictive ability. For several rare species there were significant improvements in occurrence predictions, while the results for two invasive species considered did not show the same improvements. Overall, the optimal number of species to condition upon, as well as the effects of conditioning upon an increasing number of species, varied widely among species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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22. Development of a cost-efficient automated wildlife camera network in a European Natura 2000 site.
- Author
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Kissling, W. Daniel, Evans, Julian C., Zilber, Rotem, Breeze, Tom D., Shinneman, Stacy, Schneider, Lindy C., Chalmers, Carl, Fergus, Paul, Wich, Serge, and Geelen, Luc H.W.T.
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CONVOLUTIONAL neural networks ,WILDLIFE monitoring ,BIODIVERSITY monitoring ,OPTICAL sensors ,REMOTE sensing ,DEEP learning ,ANIMAL populations - Abstract
• Automating wildlife monitoring with wireless 4G cameras and end-to-end data streams. • Remote monitoring of sensor performance, API handling and automated task management. • Deep learning for automated identification of focal species and human detection. • Total cost saving of >40 % through automation, AI and less regular site visits. • Enabling technologies allow scaling-up of a cost-efficient biodiversity monitoring. Modern approaches with advanced technology can automate and expand the extent and resolution of biodiversity monitoring. We present the development of an innovative system for automated wildlife monitoring in a coastal Natura 2000 nature reserve of the Netherlands with 65 wireless 4G wildlife cameras which are deployed autonomously in the field with 12 V/2A solar panels, i.e. without the need to replace batteries or manually retrieve SD cards. The cameras transmit images automatically (through a mobile network) to a sensor portal, which contains a PostgreSQL database and functionalities for automated task scheduling and data management, allowing scientists and site managers via a web interface to view images and remotely monitor sensor performance (e.g. number of uploaded files, battery status and SD card storage of cameras). The camera trap sampling design combines a grid-based sampling stratified by major habitats with the camera placement along a traditional monitoring route, and with an experimental set-up inside and outside large herbivore exclosures. This provides opportunities for studying the distribution, habitat use, activity, phenology, population structure and community composition of wildlife species and allows comparison of traditional with novel monitoring approaches. Images are transferred via application programming interfaces to external services for automated species identification and long-term data storage. A deep learning model for species identification was tested and showed promising results for identifying focal species. Furthermore, a detailed cost analysis revealed that establishment costs of the automated system are higher but the annual operating costs much lower than those for traditional camera trapping, resulting in the automated system being >40 % more cost-efficient. The developed end-to-end data pipeline demonstrates that continuous monitoring with automated wildlife camera networks is feasible and cost-efficient, with multiple benefits for extending the current monitoring methods. The system can be applied in open habitats of other nature reserves with mobile network coverage. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
23. Recovering connectivity through restoration corridors in a fragmented landscape in the magdalena river's valley in Colombia.
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Montes-Rojas, Andrés, Delgado-Morales, Nicolás Alejandro José, Escucha, Rafael S., Siabatto, Laura C., and Link, Andrés
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FRAGMENTED landscapes ,MAMMAL populations ,BIRD populations ,RESTORATION ecology ,ANIMAL populations ,CORRIDORS (Ecology) - Abstract
Forest fragmentation is one of the main drivers of global biodiversity loss leading to the isolation of wildlife populations. This study focuses on understanding the role of restoration corridors as a strategy promoting resilience and viability of mammal and bird populations in a fragmented landscape in Colombia. We installed 98 camera-trap stations − 8497 camera-trap days - in four different land cover categories: (1) forest fragments, (2) natural corridors, (3) stablished corridors and (4) pastures. We evaluated if restoration corridors do promote connectivity for large vertebrates and recover species richness and functional diversity lost in anthropogenically transformed pastures. We used indices of taxonomic and functional diversity and a non-metric multidimensional scaling to evaluate the influence of land cover over mammal and bird communities. Both, species richness and functional diversity have higher values in forests, followed by natural corridors and corridors and lower values in open pastures. Differences in species composition were greater between forests and pastures, and species composition of restoration corridors begins to resemble that of riparian forests and forest fragments. Our results provide initial evidence on the role of restoration corridors as an efficient strategy aimed to recover biodiversity and functional diversity in pervasively fragmented landscapes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. First Sero-Molecular Diagnosis of Toxoplasma gondii and Toxocara spp. Infections in the Police Dogs and Their Trainers in Iran.
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Asghari, Ali, Jalili, Shirin, and Azadi, Nader
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POLICE dogs ,PUBLIC health officers ,TOXOPLASMA gondii ,ANIMAL populations ,PARASITIC diseases - Abstract
Purpose: Toxoplasma gondii (T. gondii) and Toxocara spp. are two types of parasites that can infect humans and various animals, including dogs. Police dogs and their trainers have a vital role in law enforcement, and their health and well-being are crucial for them to effectively carry out their duties. No study has yet been conducted on the prevalence of T. gondii and Toxocara spp. infections among police dogs and their trainers in Iran. The objective of this study was to determine the sero-molecular prevalence of T. gondii and Toxocara spp. infections in police dogs and their trainers in Tehran, the capital of Iran. Methods: In Tehran province, the anti-narcotics police have nearly 200 well-trained police dogs. Each dog is assigned a dedicated trainer and upon completing missions, is housed separately in a designated area. In the present study, a total of 150 samples were gathered. These included 50 blood samples from randomly selected police dogs, 50 fecal samples from the same dogs, and 50 blood samples from their trainers. The Modified Agglutination Test (MAT) was performed to detect T. gondii antibodies in dog blood samples and the ELISA system was utilized to identify anti-Toxoplasma and anti-Toxocara antibodies in the sera of the dog trainers. A specific segment of the SAG2 and ITS genes were amplified via nested-PCR in order to molecularly detect T. gondii in human blood samples and Toxocara spp. in dog fecal samples. Results: Regarding serological findings, the prevalence of T. gondii in dog and human blood samples was 4% (2/50) and 10% (5/50), respectively. According to reports, the seroprevalence of Toxocara spp. in human blood samples was 6% (3/50). No statistically significant association was found between the prevalence of the examined parasites and variables (age, sex, and breed) in dogs, as well as the age variable in military personnel. Molecular findings showed that out of the 50 dog fecal samples and 50 human blood samples, there was no presence of Toxocara spp. and T. gondii, respectively. Conclusion: Understanding the prevalence of parasitic infections helps public health officials assess the risk to human and animal populations. This information can guide the development of prevention and control measures to reduce the spread of these infections. Overall, the prevalence of parasitic infections, particularly T. gondii and Toxocara spp., in police dogs and their trainers remains uncertain and necessitates further in-depth research. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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25. Chronic metal contamination shapes the size structure of Gammarus fossarum populations in French headwater rivers.
- Author
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Lalouette, A., Degli Esposti, D., Colomb, C., Garnero, L., Quéau, H., Recoura-Massaquant, R., and Chaumot, A.
- Subjects
BIOLOGICAL evolution ,LIFE history theory ,KEYSTONE species ,CENSUS ,ANIMAL populations - Abstract
Assessing the effects of multigenerational exposure of aquatic animal populations to chemical contamination is essential for ecological risk assessment. However, beyond rare examples reporting the sporadic emergence of a toxicological tolerance within populations that persist in contaminated environments, conclusive results are even more limited from field studies when it comes to the alteration of life-history traits. Here, we investigated whether long-term exposure to cadmium (Cd) influences size-related life-history traits (i.e., size at puberty, median adult size, maximum size) in Gammarus fossarum, a keystone species of European stream ecosystems. We studied 13 field populations of G. fossarum (cryptic lineage B) living in headwater rivers located in natural areas scattered at a large geographical scale and exposed to contrasted bioavailable Cd contamination levels due to different local geochemical backgrounds. We achieved a detailed description of the physical and physicochemical conditions of the river reaches investigated. Land-use parameters, hydrological characteristics (flow, slope, river width, flow structure, mosaic of substrates), and physicochemical conditions (temperature, conductivity, dissolved oxygen) were measured. Metallic bioavailable contamination was assessed using a standardized active biomonitoring procedure (Gammarus caging). Based on the field demographic census of the 13 populations, our results demonstrated that chronic Cd contamination significantly influences life-history in the G. fossarum species, with a significant reduction in all size traits of populations (size at puberty, median adult size, maximum size). In addition, we confirmed Cd-tolerance in contaminated populations during exposure tests in the laboratory. Various hypotheses can be then put forward to explain the modification of size-related life-history traits: a direct toxic effect of Cd, a cost of Cd-tolerance, or an adaptive evolution of life-history exposed to toxic pressure. Highlights: Characterization of Cd-exposure, Cd-tolerance, and size distribution of 13 Gammarus field populations. Occurrence of natural high levels of Cd exposure in headwater rivers. Reduced size at puberty, reduced mean and maximal body size in Cd-exposed populations. Cost of tolerance versus life-history adaptation as underlying evolutionary mechanisms. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. Virtual wildlife tourism: an ideal form of ecotourism?
- Author
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Burns, Georgette Leah and Benz-Schwarzburg, Judith
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ECOTOURISM ,VIRTUAL tourism ,ANIMAL populations ,CAPTIVITY ,TOURISTS ,DIGNITY ,POSTHUMANISM - Abstract
Wildlife populations are plummeting worldwide and captivity, of at least some, species is increasingly being challenged from an ethical perspective. When captivity serves human entertainment, poor treatment as well as unequal power-relationships are problematic. Particularly for wildlife ecotourism then, we ask: is the future virtual? Taking a posthumanist approach, this conceptual manuscript considers whether presenting technologically created images to tourists can equitably foreground non-human rights, welfare, and agency. We highlight examples of tourism involving wildlife in virtual settings to explore possible advantages and disadvantages of this type of experience for human and non-human stakeholders. This enables us to explore how the virtual experience fits with the concept of ecotourism. The argument is made that the ideals of wildlife ecotourism can best, and perhaps only, be met virtually – but only if we use images of non-human animals who are represented with dignity and respect. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Disturbance and ecosystem management interact to shape reptile body condition.
- Author
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Macdonald, K. J., Doherty, T. S., Hradsky, B. A., and Driscoll, D. A.
- Subjects
- *
RAINFALL , *PRESCRIBED burning , *RED fox , *ECOSYSTEM management , *ECOLOGICAL disturbances , *ANIMAL populations - Abstract
Fire, invasive predators and low rainfall are key disturbances that interact to negatively impact wildlife. Reptiles are a highly threatened group, yet they have rarely been the focus of threat interaction research. Research assessing the impacts of disturbance on wildlife have typically focussed on changes in species richness and abundance. However, these metrics largely overlook the non‐lethal effects on individuals and populations persisting within disturbed landscapes. Body condition is an individual‐level response metric that is easily obtainable and provides insight into the cumulative behavioural and morphological changes within a population. We used a landscape‐scale natural experiment in southern Australia to investigate the impacts of prescribed fire severity, invasive red fox (Vulpes vulpes) control, low rainfall conditions and their interactive effects on reptile body condition. Low rainfall had pervasive negative effects on body condition, while prescribed fire had negative effects on the larger, viviparous species. We found a three‐way interactive effect, whereby the negative effects of fire and low rainfall were greater in areas where red foxes were controlled. These results indicate that there are complex ecological interactions at play, potentially including intra‐specific competition and interspecific interactions. Lower body condition in disturbed environments could have lasting implications for individual fitness and population persistence. For instance, species with lower body condition one‐year post‐fire could be more vulnerable to another fire event, compared to species that are able to maintain condition in post‐fire landscapes. With reptile body condition lower in a drier year, we advise minimising additional disturbance (e.g. avoid prescribed fires) during low rainfall years and drought periods. Along with research into ecological interactions, understanding how body condition indices relate to altered fitness is a priority knowledge gap. Such research could improve the ability to predict how species and populations will respond to future disturbances, a key challenge in wildlife disturbance research. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. Behavioral plasticity shapes population aging patterns in a long-lived avian scavenger.
- Author
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Acácio, Marta, Gahm, Kaija, Anglister, Nili, Vaadia, Gideon, Hatzofe, Ohad, Harel, Roi, Efrat, Ron, Nathan, Ran, Pinter-Wollman, Noa, and Spiegel, Orr
- Subjects
- *
OLDER people , *POPULATION dynamics , *ANIMAL populations , *SOCIAL movements , *OLD age - Abstract
Studying the mechanisms shaping age-related changes in behavior ("behavioral aging") is important for understanding population dynamics in our changing world. Yet, studies that capture within-individual behavioral changes in wild populations of long-lived animals are still scarce. Here, we used a 15-y GPS-tracking dataset of a social obligate scavenger, the griffon vulture (Gyps fulvus), to investigate age-related changes in movement and social behaviors, and disentangle the role of behavioral plasticity and selective disappearance in shaping such patterns. We tracked 142 individuals for up to 12 y and found a nonlinear increase in site fidelity with age: a sharp increase in site fidelity before sexual maturity (<5 y old), stabilization during adulthood (6 to 15 y), and a further increase at old age (>15 y). This pattern resulted from individuals changing behavior throughout their life (behavioral plasticity) and not from selective disappearance. Mature vultures increased the predictability of their movement routines and spent more nights at the most popular roosting sites compared to younger individuals. Thus, adults likely have a competitive advantage over younger conspecifics. These changes in site fidelity and movement routines were mirrored in changes to social behavior. Older individuals interacted less with their associates (decreasing average strength with age), particularly during the breeding season. Our results reveal a variety of behavioral aging patterns in long-lived species and underscore the importance of behavioral plasticity in shaping such patterns. Comprehensive longitudinal studies are imperative for understanding how plasticity and selection shape the persistence of wild animal populations facing human-induced environmental changes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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29. Predicting population‐level impacts of projected climate heating on a temperate freshwater fish.
- Author
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Mintram, Kate S., Brown, A. Ross, Maynard, Samuel K., Thorbek, Pernille, and Tyler, Charles R.
- Subjects
- *
PHYSIOLOGICAL effects of temperature , *PHYSIOLOGY , *PLANT physiology , *THREESPINE stickleback , *PREY availability , *ANIMAL populations - Abstract
Climate heating has the potential to drive changes in ecosystems at multiple levels of biological organization. Temperature directly affects the inherent physiology of plants and animals, resulting in changes in rates of photosynthesis and respiration, and trophic interactions. Predicting temperature‐dependent changes in physiological and trophic processes, however, is challenging because environmental conditions and ecosystem structure vary across biogeographical regions of the globe. To realistically predict the effects of projected climate heating on wildlife populations, mechanistic tools are required to incorporate the inherent physiological effects of temperature changes, as well as the associated effects on food availability within and across comparable ecosystems. Here we applied an agent‐based bioenergetics model to explore the combined effects of projected temperature increases for 2100 (1.4, 2.7, and 4.4°C), and associated changes in prey availability, on three‐spined stickleback (Gasterosteus aculeatus) populations representing latitudes 50, 55, and 60°N. Our results showed a decline in population density after a simulated 1.4°C temperature increase at 50°N. In all other modeled scenarios there was an increase (inflation) in population density and biomass (per unit area) with climate heating, and this inflation increased with increasing latitude. We conclude that agent‐based bioenergetics models are valuable tools in discerning the impacts of climate change on wild fish populations, which play important roles in aquatic food webs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. Nestling sex and behaviour determine the host preference of insect vectors in avian nests.
- Author
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García‐del Río, Marina, Castaño‐Vázquez, Francisco, Martínez, Javier, Martínez‐de la Puente, Josué, Cantarero, Alejandro, García‐Velasco, Javier, Merino, Yago, and Merino, Santiago
- Subjects
- *
CERATOPOGONIDAE , *BIRD nests , *ANIMAL populations , *SEXISM , *INSECT hosts - Abstract
Sexual differences in pathogen prevalence in wildlife often arise from varying susceptibility influenced by factors such as sex hormones and exposure to pathogens. In the case of vector‐borne pathogens, host selection by insect vectors determines the exposure of hosts to infections, largely affecting the transmission of these infectious diseases. We identify the blood‐feeding patterns of insect vectors in Blue Tit (Cyanistes caeruleus) nestlings in a 3‐year study. Blood from both nestlings and insect vectors (Culicoides spp. and Simuliidae) captured inside nest‐boxes were used to molecularly determine the sex of the host. We then compared the sex‐ratios of the nestlings that had been bitten and those of the complete brood in each nest. We found that males were bitten more frequently than females in 2021, when males weighed less in comparison to other years. Additionally, we molecularly identified bitten nestlings individually by genotyping the DNA of blood obtained from both, the vector's abdomen and nestlings of each brood in 2022. Nestlings more frequently bitten by vectors were males, weighed less and were closest to the nest entrance. To our knowledge this is the first study identifying the nestling selection by insect vectors in bird nests under natural conditions. These results contribute to understanding the mechanisms of host selection by insect vectors, shedding light on pathogen transmission and offering insights into the observed sex‐biased infections in wildlife populations. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Mammary gland, skin and soft tissue tumors in pet cats: findings of the feline tumors collected from 2002 to 2022.
- Author
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Giugliano, Roberta, Dell'Anno, Filippo, De Paolis, Livia, Crescio, Maria Ines, Ciccotelli, Valentina, Vivaldi, Barbara, and Razzuoli, Elisabetta
- Subjects
SOFT tissue tumors ,CAT diseases ,MAMMARY glands ,CATS ,POISSON regression ,ANIMAL populations - Abstract
Introduction: Cancer is a leading cause of death in cats, and the rate of such disease has been increasing recently. Nonetheless, feline oncology represents an important area of study not only for the health and wellbeing of cats but also for human health since various types of cancer in cats share similarities to those found in humans. Therefore, epidemiological studies on feline oncology may suggest environmental and genetic factors contributing to cancer in cats, which can eventually be translated to improve human cancer care. Method: To provide an initial understanding of the epidemiology of feline neoplasms, a descriptive study was undertaken using a dataset documenting cases of feline cancer gathered fromthe Liguria region (northwest Italy) spanning from 2002 to 2022. The database includes tumor location, morphological codes of the International Classification of Diseases for Oncology, 3rd Edition (ICD-O-3), feline's breed, sex, neuter status, date of birth, date of diagnosis, national territorial unit code of the town of the owner's residence, and an alphanumeric string uniquely identifying the owner's surname. Results and discussion: The dataset involves a population of 4,399 cats, including 3,195 females (1,425 neutered) and 1,204 males (750 neutered). Our results indicate that mammary gland tumors are the most represented tumors in the female population, while soft tissue and skin cancers appear to have a higher abundance in the male population during the periods investigated (2002-2022). Moreover, Poisson regression analysis showed that not neutered female cats have a significantly increased risk of developing mammary gland tumors compared to the neutered female population [proportional morbidity ratio (PMR) neutered vs. not neutered = 0.58, 95% CI: 0.47-0.72]; meanwhile, for both sexes, for soft tissue and skin tumors, being neutered appears to be a risk factor (PMR neutered vs. not neutered = 2.26, 95% CI: 1.86-2.73; PMR neutered vs. not neutered = 1.16, 95% CI: 0.89-1.51). Finally, the evaluation of the Ligurian municipalities pollution, based on wild boars data (i.e., biomonitors), which coexisted with cats, was correlated to cancer development for all the tumors investigated (in polluted areas, estimated PMRs ranged from 42.61 to 80.13, 95% CI: 29.94-105.11). Overall, the data presented here suggest the use of the feline population as a possible animal model for human health, i.e., sentinel. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. Heavy Metal Contamination in Birds from Protected Regions in the Amazon.
- Author
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Loera, Yeraldi, Gruppi, Cristian, Swing, Kelly, Campbell‐Staton, Shane C., Milá, Borja, and Smith, Thomas B.
- Subjects
- *
HEAVY metals , *POLLUTION , *PETROLEUM , *ECOLOGICAL impact , *PROTECTED areas , *BIRD populations , *ANIMAL populations - Abstract
The extraction of crude oil and gold has substantially increased heavy metal contamination in the environment, yet the study of wildlife exposure and biological response to this pollution remains nascent even in the most biodiverse places in the world. We present a survey of heavy metal exposure in the feathers of wedge‐billed woodcreepers (
Glyphorynchus spirurus ), a resident neotropical bird found within protected regions of the Amazon near oil and gold extraction sites. Our results show elevated heavy metal contamination in samples collected from protected areas proximate to known oil and gold extraction. Surprisingly, several samples from remote reference sites also displayed elevated levels of various heavy metals, suggesting a background of natural deposition or complex heavy metal contamination in the environment from anthropogenic sources. These results highlight the need to understand the ecological and biological impacts of increased heavy metal exposure on wildlife across space and time, including remote regions of the world purportedly untouched by these human‐mediated stressors. Toward this goal, historical and contemporary data from native bird populations may provide crucial indicators for heavy metal contamination and exposure in wildlife and human communities.Environ Toxicol Chem 2024;00:1–7. © 2024 The Author(s).Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
33. Global expansion of human-wildlife overlap in the 21st century.
- Author
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Deqiang Ma, Abrahms, Briana, Allgeier, Jacob, Newbold, Tim, Weeks, Brian C., and Carter, Neil H.
- Subjects
- *
TWENTY-first century , *SURFACE of the earth , *POPULATION density , *BIODIVERSITY conservation , *ANIMAL populations , *CLIMATE change - Abstract
Understanding the extent to which people and wildlife overlap in space and time is critical for the conservation of biodiversity and ecological services. Yet, how global change will reshape the future of human-wildlife overlap has not been assessed. We show that the potential spatial overlap of global human populations and 22,374 terrestrial vertebrate species will increase across ~56.6% and decrease across only ~11.8% of the Earth's terrestrial surface by 2070. Increases are driven primarily by intensification of human population densities, not change in wildlife distributions caused by climate change. The strong spatial heterogeneity of future human-wildlife overlap found in our study makes it clear that local context is imperative to consider, and more targeted area-based land-use planning should be integrated into systematic conservation planning. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Increasing environmental variability inhibits evolutionary rescue in a long-lived vertebrate.
- Author
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Clark-Wolf, T. J., Boersma, P. Dee, Plard, Floriane, Rebstock, Ginger A., and Abrahms, Briana
- Subjects
- *
WILDLIFE conservation , *ANIMAL populations , *ANIMAL species , *ZOOARCHAEOLOGY , *PENGUINS - Abstract
Evolutionary rescue, whereby adaptive evolutionary change rescues populations from extinction, is theorized to enable imperiled animal populations to persist under increasing anthropogenic change. Despite a large body of evidence in theoretical and laboratory settings, the potential for evolutionary rescue to be a viable adaptation process for free-ranging animals remains unknown. Here, we leverage a 38-year dataset following the fates of 53,959 Magellanic penguins (Spheniscus magellanicus) to investigate whether a free-ranging vertebrate species can morphologically adapt to long-term environmental change sufficiently to promote population persistence. Despite strong selective pressures, we found that penguins did not adapt morphologically to long-term environmental changes, leading to projected population extirpation. Fluctuating selection benefited larger penguins in some environmental contexts, and smaller penguins in others, ultimately mitigating their ability to adapt under increasing environmental variability. Under future climate projections, we found that the species cannot be rescued by adaptation, suggesting similar constraints for other long-lived species. Such results reveal how fluctuating selection driven by environmental variability can inhibit adaptation under long-term environmental change. Our eco-evolutionary approach helps explain the lack of adaptation and evolutionary rescue in response to environmental change observed in many animal species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Habitat destruction and implications for wildlife conservation in protected areas, Tanzania.
- Author
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Lwankomezi, Emmanuel B. and Kaganga, Laison
- Subjects
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HABITAT destruction , *WILDLIFE management areas , *WILDLIFE conservation , *HABITAT conservation , *ANIMAL populations - Abstract
Protected areas maintain the ecosystem and conserve wildlife, but they face threats from habitat destruction. This paper assesses the drivers of habitat destruction and their implications on wildlife conservation in Tanzania. Data were collected from 607 respondents using a questionnaire and Landsat 8 Operational Land images from 2013 to 2023 to detect land use changes in the Makao Wildlife Management area. A multiple regression model analysed the relationship between habitat destruction (dependent variables) and human population increase, crop cultivation, livestock grazing, inadequate economic incentives, and wildlife population (independent variables). Between 2013 and 2023, agricultural and settlement areas increased by 39% and 686%, while Makao WMA and water bodies decreased by 11% and 39%. Human population (
p .0095), crop cultivation (p .0024), and livestock grazing (p .0033) significantly contributed to habitat destruction. Community engagement is essential to promote sustainable conservation and mitigation of impacts to ensure Wildlife Management Areas remain healthy and viable for wildlife. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
36. Tracking data as an alternative to resighting data for inferring population ranges.
- Author
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Linssen, Hans, Loon, E. Emiel, Shamoun‐Baranes, Judy Z., Vergin, Lisa, Leyrer, Jutta, and Nolet, Bart A.
- Subjects
- *
ANIMAL populations , *SPATIAL variation , *CITIZEN science , *SPECIES distribution , *DATA science - Abstract
Aim Location Taxon Methods Results Main Conclusions Large‐scale space use and geographical ranges of animal populations are central topics in ecology. Whereas they are traditionally often based on citizen science or professional sightings of (marked) animals, recent technological developments have presented GPS tracking as an alternative method for inferring space use at the population level. Tracking devices are however much more expensive than traditional marks, rings or collars, leading to datasets that typically consist of much fewer individuals. We study how GPS tracking data and citizen science resighting data of marked individuals compare as alternative sources for inferring range size.Northwestern Europe.Bewick's swan (Cygnus columbianus bewickii).We calculated Bewick's swan range sizes from a wealth of GPS tracking and resighting data during winter, the period of the year when both data types are abundant. We examined the effect of the number of individuals and the total number of spatial records (either resightings or GPS fixes) on the inferred range size. Moreover, we combined GPS tracks with resightings of the same individuals to empirically determine spatial variation in resighting rates.Tracked individuals generated records across an area 1.5–2 times larger than individuals that were merely resighted. Moreover, any given number of daily GPS records (rather than GPS‐tracked individuals) yielded an area 1.5 times larger than that same number of resighting records. A small number of GPS‐tracked individuals (~20) was sufficient to yield a larger range size compared to much higher numbers of resighted individuals (well over 400). Spatial variation in resighting rates corresponded well with the differences in range size from the two data types, indicating that spatial gaps in observer effort can hamper range estimations.When combined with resighting data, tracking data can be used to indicate areas of low observer effort. Although citizen science resightings are essential for collecting various types of biological information, we show that GPS tracking presents a highly efficient alternative to traditional marking for assessing large‐scale space use and population ranges, requiring far fewer individuals to be used. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. Dealing with the risk of fire in carbon sequestration strategies: Diverse forests or plantation monocultures?
- Author
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Smith, Warwick J. S., Bekessy, Sarah A., Ward, Michelle, and Wintle, Brendan A.
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- *
CARBON sequestration , *EXTREME weather , *CLIMATE change , *CARBON pricing , *ANIMAL populations - Abstract
Climate and land‐use change pose unprecedented threats to ecosystems, economies, and communities worldwide. To help mitigate the climate crisis, restoration is a rapidly growing industry used to offset carbon emissions. The most common approach is to plant fast‐growing monocultures with the aim of sequestering as much carbon as possible in the shortest time. However, there has been little economic analysis of planting options that explicitly address short and long‐term ecological risks such as fire, disease, and environmental change. Here we develop a method for quantifying ecological risks from fire to sequestration investments and show how these risks can be factored into an analysis of long‐term financial returns relative to opportunity costs. In the case study presented, we find that the apparent advantage of fast‐growing monoculture plantations is likely to be outweighed by the long‐term fire risks to the carbon stored in them. Our analytical framework provides a widely applicable approach to comparing planting options against each other and other land uses, considering key uncertainties. With climate change already manifesting through extreme weather events, rising sea levels, and shifting wildlife populations, our framework can be used to make informed decisions about the best solutions to increase carbon sequestration, reduce ecological risks, and reduce climate impacts with greater certainty. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Longitudinal gut microbiome dynamics in relation to age and senescence in a wild animal population.
- Author
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Worsley, Sarah F., Davies, Charli S., Lee, Chuen Zhang, Mannarelli, Maria‐Elena, Burke, Terry, Komdeur, Jan, Dugdale, Hannah L., and Richardson, David S.
- Subjects
- *
OLDER people , *AGE , *ANIMAL populations , *GUT microbiome , *CAPTIVE wild animals - Abstract
In humans, gut microbiome (GM) differences are often correlated with, and sometimes causally implicated in, ageing. However, it is unclear how these findings translate in wild animal populations. Studies that investigate how GM dynamics change within individuals, and with declines in physiological condition, are needed to fully understand links between chronological age, senescence and the GM, but have rarely been done. Here, we use longitudinal data collected from a closed population of Seychelles warblers (Acrocephalus sechellensis) to investigate how bacterial GM alpha diversity, composition and stability are associated with host senescence. We hypothesised that GM diversity and composition will differ, and become more variable, in older adults, particularly in the terminal year prior to death, as the GM becomes increasingly dysregulated due to senescence. However, GM alpha diversity and composition remained largely invariable with respect to adult age and did not differ in an individual's terminal year. Furthermore, there was no evidence that the GM became more heterogenous in senescent age groups (individuals older than 6 years), or in the terminal year. Instead, environmental variables such as season, territory quality and time of day, were the strongest predictors of GM variation in adult Seychelles warblers. These results contrast with studies on humans, captive animal populations and some (but not all) studies on non‐human primates, suggesting that GM deterioration may not be a universal hallmark of senescence in wild animal species. Further work is needed to disentangle the factors driving variation in GM‐senescence relationships across different host taxa. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. Persistent Illegal Hunting of Wildlife in an African Landscape: Insights from a Study in the Luangwa Valley, Zambia.
- Author
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Zyambo, Paul, Mwitwa, Jacob, Kalaba, Felix Kanungwe, and Kazonga, Eustarckio
- Subjects
- *
NATURE reserves , *BASIC needs , *JUDGMENT sampling , *PROTECTED areas , *LAW enforcement , *POACHING , *ANIMAL populations - Abstract
Simple Summary: The illegal hunting (poaching) of wildlife has persisted for decades and adversely effected wildlife populations in the Luangwa Valley, Zambia. It has not been clearly understood why illegal hunting has continued notwithstanding efforts to control it. Therefore, this study was conducted to understand why illegal hunting has persisted despite increased mitigation efforts. The study revealed that illegal hunting has continued because its main root causes are the critical need for survival and sustaining the livelihoods of local hunters, which were not adequately addressed. Furthermore, law enforcement, which was the main intervention measure, failed to adequately deter local hunters from poaching wildlife because it could not address the main root causes of illegal hunting. The study concluded that the illegal harvesting of resources in protected areas may persist when the local people's key motivations for illegal harvesting relate to their critical need to survive and maintain their livelihoods and the main mitigation efforts do not address these critical needs. These study findings are valuable in providing an understanding of how the critical need for survival and maintaining livelihoods and other factors influence the persistence of illegal hunting and in guiding the development of a strategy for the effective control of poaching in the Luangwa Valley. Decades of illegal hunting (poaching) have adversely affected wildlife populations and thereby limited sustainable wildlife conservation in the Luangwa Valley, Zambia. Despite intervention efforts to address the problem, the illegal hunting of wildlife has persisted. Therefore, this study was conducted to understand the persistence of illegal hunting by investigating the drivers of poaching and intervention measures using a mixed methods approach. Stratified random sampling was used to collect data from 346 respondents through structured questionnaires. Purposive sampling was used to collect data through nine focus group discussions and three in-depth interviews with experts. The study revealed that persistent illegal hunting was mainly driven by people's critical need for survival and sustaining their livelihoods and not by inadequate law enforcement as presumed by resource managers. Although law enforcement was the most prevalent intervention measure, it did not deter local illegal hunters because their main motivations for poaching were not effectively addressed. The key implication of these findings is that where the illegal harvesting of natural resources in protected areas by local resource users is driven by people's critical need for survival and a livelihood, which is ineffectively addressed, illegal harvesting may persist even with increased law enforcement. This study provides empirical evidence, novel conceptual knowledge and an understanding of how prevalent drivers of poaching and other factors may have influenced persistent illegal hunting in the Luangwa Valley. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. Diagnosis of a Rare Rickettsia felis Infection Complicated with Unusual Pericardial Effusion and Cardiac Tamponade Using an mNGS Test.
- Author
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Po, Tien-Lung, Huang, Chien-Hsien, Lin, Chia-Hsun, Hung, Huei-Fong, and Baindara, Piyush
- Subjects
- *
RICKETTSIAL diseases , *DOMESTIC animals , *CAT flea , *ANIMAL populations , *FELIS , *CARDIAC tamponade - Abstract
The occurrence of sporadic rickettsial infections has been consistently undervalued and overlooked, primarily owing to a limited emphasis on routine examinations for rickettsioses in clinical practice. At present, the immunofluorescence assay is the prevailing diagnostic method for suspected rickettsioses that enables the detection of specific antibodies against rickettsia in human serum. Herein, we present an exceptional instance of rickettsial infection that was characterized by a rare manifestation of extensive pericardial effusion leading to dyspnea and cardiac tamponade. A diagnosis of chronic fibrosing pericarditis was established based on pericardium tissue obtained through pericardiotomy, and a conclusive metagenomic next‐generation sequencing test confirmed the presence of Rickettsia felis infection. The cat flea, scientifically known as Ctenocephalides felis, is the predominant carrier of R. felis. An escalating incidence of human R. felis infections has raised concerns, particularly in light of the burgeoning population of domesticated animals in many contemporary societies. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. How many sequences should I track when applying the random encounter model to camera trap data?
- Author
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Palencia, P. and Barroso, P.
- Subjects
- *
RED deer , *FALLOW deer , *RED fox , *ANIMAL tracks , *ANIMAL populations , *WILD boar - Abstract
The random encounter model (REM) is a camera trapping method to estimate population density (i.e. number of individuals per unit area) without the need for individual recognition. The REM can be applied considering camera trap data only by tracking the passages of animals in front of the camera (i.e. sequences). However, it has not been assessed how the number of sequences tracked (i.e. trajectory of the animal reconstructed) influences the REM estimates. In this context, we aimed to gain further insights into the relationship between the number of sequences tracked and reliability in REM estimates to optimize its applicability. We monitored multiple species using camera traps, and we applied REM to estimate population density. We considered red fox Vulpes vulpes, roe deer Capreolus capreolus, fallow deer Dama dama, red deer Cervus elaphus and wild boar Sus scrofa as model species. We tracked from a minimum of 154 (red fox) to a maximum of 527 (red deer) sequences per species, and we then sampled the dataset to simulate different scenarios in which a lower number of sequences were tracked (20, 40, 80 and 160). We also assessed the effect of adjusting the survey period to the minimum necessary to record the desired number of sequences. Our results suggest that tracking around 100 sequences returns a precision level equivalent to the one obtained by tracking a considerably higher number of sequences and reduced and optimized the human effort necessary to apply REM. Tracking less than 40 sequences could result in low precise density estimates. Our results also highlighted the relevance of considering study periods of ca. 2 months to increase the number of sequences recorded and tracking a random sample of them. Our results contribute to the optimization and harmonization of REM as a reference method to estimate wildlife population density without the need for individual identification. We make clear recommendations on the cost‐effective sample size for estimating REM parameters, optimizing the human effort when applying REM, and discouraging REM applications based on low sample sizes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
42. Christmas Bird Count data are a reliable harvest-independent index for Ruffed Grouse monitoring in the eastern United States.
- Author
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Geary, Brock, Williams, Lisa, Long, C Robert, Tyl, Reina M, and Gagne, Roderick B
- Subjects
- *
ANIMAL populations , *GAME & game-birds , *BIRD populations , *BIRD population estimates , *WILDLIFE management - Abstract
Using data from the mid-1990s to the present, we assessed correlations of Ruffed Grouse (Bonasa umbellus) hunter cooperator reports from seven states to Breeding Bird Survey, Christmas Bird Count, and eBird data to determine which program's trends best reflected patterns seen in hunter-sourced data that has historically been used for monitoring purposes. Christmas Bird Count data most closely reflected state-wide long-term trends in cooperator flush rates. Using an analytical approach that accounts for sources of bias and examines abundance at a finer spatial scale, we observed a pattern of decline across our study area. In recent decades, Ruffed Grouse populations in the eastern United States are thought to have suffered persistent declines due to a combination of young forest habitat loss and West Nile virus mortality. Declining hunter participation in much of the species' range has highlighted the need to identify harvest-independent indices of grouse abundance to enable continued monitoring of regional long-term trends. Recent analytical methods can better capture complex trends in population dynamics, account for biases inherent to community-sourced data, and potentially inform designs of future survey efforts aimed at fulfilling priority monitoring and research needs. Comparable results across varying statistical methodologies suggest that our inferences are robust, demonstrating that Christmas Bird Count data can be used to inform regional monitoring efforts for grouse and other cryptic game bird populations, but require careful consideration of program designs and protocols to identify and implement data appropriately. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Circulation of influenza viruses in the dog population in Kazakhstan (2023–2024).
- Author
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Glebova, Tatyana I., Klivleyeva, Nailya G., Saktaganov, Nurbol T., Shamenova, Mira G., Lukmanova, Galina V., Baimukhametova, Assem M., Baiseiit, Sagadat B., Ongarbayeva, Nuray S., Orynkhanov, Kanat A., Ametova, Anna V., and Ilicheva, Aitolkyn K.
- Subjects
- *
BLOOD serum analysis , *ANIMAL populations , *H1N1 influenza , *CORONAVIRUSES , *INFLUENZA - Abstract
Background: Dogs in close contact with humans can serve as a source of potentially dangerous reassortant influenza viruses (IVs) with zoonotic potential. The dog’s body can serve as a vessel for the emergence of new IVs. These new viruses can become a source of infection for other animals and humans. The potential for zoonotic transmission of IVs from dogs to humans poses a public health risk. Aim: Study of the circulation of IVs in the dog population in Almaty, Kazakhstan. Methods: Biosamples (oropharyngeal swabs and blood serum) from dogs were collected from veterinary clinics in Almaty in 2023–2024. Samples were screened using RT-PCR, HI assay, and ELISA. Results: RT-PCR analysis of 355 nasopharyngeal swabs showed the presence of influenza A virus (IAV) in 32 samples (9.01% of the total number of samples analyzed). When subtyping IAV H1N1 RNA was detected in 19 swabs (5.35%). IAV subtype could not be determined in 13 PCR-positive samples (3.66%). The genetic material of IAV H3N2, H5, H7, and H9, as well as coronavirus, bocavirus, and adenovirus has not been identified. In a serological analysis of 180 blood sera using ELISA, antibodies to IAV were detected in 5.56% (n = 10). The results of the HI assay showed the presence of antihemagglutinins to A/H1N1pdm in 6.11% (11 samples), to A/H3N2 in 9.44% (17 samples), and no antibodies to IAV H5, H7, and type B were detected. Conclusion: There is no information about human infection with any canine influenza virus. However, many cases of infection in dogs with human IAVs H1N1, H1N1pdm09, and H3N2 have been described. When dogs are co-infected with different IAVs, new recombinant IAVs may emerge that can infect humans and other animals. Therefore, ongoing global surveillance of animal populations is necessary to monitor the evolution and circulation of viruses dangerous to public health. This is also important for timely preparation for the emergence of a new zoonotic influenza virus that has pandemic potential for humans. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. Broad‐scale seasonal climate tracking is a consequence, not a driver, of avian migratory connectivity.
- Author
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Somveille, Marius, Bossu, Christen M., DeSaix, Matthew G., Alvarado, Allison H., Gómez Villaverde, Sergio, Rodríguez Otero, Genaro, Hernández‐Baños, Blanca E., Smith, Thomas B., and Ruegg, Kristen C.
- Subjects
- *
ANIMAL migration , *ANIMAL populations , *MIGRATORY animals , *GENETIC markers , *ENVIRONMENTAL refugees , *BIRD populations - Abstract
Tracking climatic conditions throughout the year is often assumed to be an adaptive behaviour underlying seasonal migration patterns in animal populations. We investigate this hypothesis using genetic markers data to map migratory connectivity for 27 genetically distinct bird populations from 7 species. We found that the variation in seasonal climate tracking across our suite of populations at a continental scale is more likely a consequence, rather than a direct driver, of migratory connectivity, which is primarily shaped by energy efficiency—i.e., optimizing the balance between accessing available resources and movement costs. However, our results also suggest that regional‐scale seasonal precipitation tracking affects population migration destinations, thus revealing a potential scale dependency of ecological processes driving migration. Our results have implications for the conservation of these migratory species under climate change, as populations tracking climate seasonally are potentially at higher risk if they adapt to a narrow range of climatic conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. Methicillin-resistant Staphylococcus aureus prevalence in food-producing animals and food products in Saudi Arabia: A review.
- Author
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Alkuraythi, Dalal M. and Alkhulaifi, Manal M.
- Subjects
- *
METHICILLIN-resistant staphylococcus aureus , *FOOD of animal origin , *SUSTAINABILITY , *DRUG resistance in bacteria , *ANIMAL populations - Abstract
In Saudi Arabia, the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) in food and livestock represents a major public health hazard. The emergence of livestock-associated MRSA has heightened the risk of human infection with comparable virulence traits. The lack of information about MRSA transmission in our region hinders accurate risk assessment, despite its detection in food animals and retail foods. Adopting a One Health approach is essential for effectively combating MRSA in Saudi Arabia. This method unites actions in the human, animal, and environmental spheres. To combat MRSA contamination, surveillance measures need strengthening; interdisciplinary collaboration among healthcare professionals, veterinarians, and environmental scientists is crucial, and targeted interventions must be implemented in local food chains and animal populations. Through a holistic strategy, public health and sustainable food production in the region are protected. This review aims to improve public health interventions by increasing understanding of MRSA prevalence and related risks in local food chains and animal populations. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. IGF-1 induces sex-specific oxidative damage and mortality in a songbird.
- Author
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Lendvai, Ádám Z., Tóth, Zsófia, Mahr, Katharina, Pénzes, Janka, Vogel-Kindgen, Sarah, Gander, Bruno A., and Vágási, Csongor I.
- Subjects
- *
LIFE history theory , *ANIMAL populations , *LABORATORY animals , *INDIVIDUAL differences , *SONGBIRDS - Abstract
The insulin-like growth factor 1 (IGF-1) is a pleiotropic hormone that regulates essential life-history traits and is known for its major contribution to determining individual ageing processes. High levels of IGF-1 have been linked to increased mortality and are hypothesised to cause oxidative stress. This effect has been observed in laboratory animals, but whether it pertains to wild vertebrates has not been tested. This is surprising because studying the mechanisms that shape individual differences in lifespan is important to understanding mortality patterns in populations of free-living animals. We tested this hypothesis under semi-natural conditions by simulating elevated IGF-1 levels in captive bearded reedlings, a songbird species with an exceptionally fast pace of life. We subcutaneously injected slow-release biodegradable microspheres loaded with IGF-1 and achieved a systemic 3.7-fold increase of the hormone within the natural range for at least 24 h. Oxidative damage to lipids showed marked sexual differences: it significantly increased the day after the manipulation in treated males and returned to baseline levels four days post-treatment, while no treatment effect was apparent in females. Although there was no overall difference in survival between the treatment groups, high initial (pre-treatment) IGF-1 and low post-treatment plasma malondialdehyde levels were associated with enhanced survival prospects in males. These results suggest that males may be more susceptible to IGF-1-induced oxidative stress than females and quickly restoring oxidative balance may be related to fitness. IGF-1 levels evolve under opposing selection forces, and natural variation in this hormone's level may reflect the outcome of individual optimization. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Spatial distribution, activity patterns, and influence of roads on mammals in the Qinling Mountains of China.
- Author
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Sun, Yuting, Yang, Dongdong, Gong, Congran, Hu, Han, Su, Lina, Li, Peiwei, Li, Yinhu, Liu, Yan, Wu, Xiaomin, and Zhang, Hongfeng
- Subjects
- *
SPECIES distribution , *INFRARED cameras , *NATIONAL parks & reserves , *NATURE reserves , *ROCK concerts , *WILD boar , *ANIMAL populations - Abstract
Species distribution and activity patterns vary across regions, and these patterns reveal key information about the biology of a given species. However, such data in Niubeiliang National Nature Reserve located in the Qinling Mountains, Shaanxi Province, China, are inadequate due to limited monitoring studies. From September 2017 to December 2019, 57 infrared cameras were installed to monitor species distribution relative to distance from National Highway 210, and spatial and temporal activity patterns in Niubeiliang National Nature Reserve (elevation range 1,100 to 2,802 m). Sixteen species of mammals were recorded in our survey. The 4 most frequently detected species were Reeves's Muntjac (Muntiacus reevesi), Wild Boar (Sus scrofa), Pere David's Rock Squirrel (Sciurotamias davidianus), and Golden Takin (Budorcas taxicolor bedfordi). Daily patterns of these species indicated that Reeves's muntjacs and golden takins were more active at dawn and dusk, whereas wild boars and Pere David's rock squirrels were more active during the day. The relative abundance index of these mammals varied seasonally. Wild boars and Pere David's rock squirrels showed no obvious preference in elevation distribution, Reeves's muntjacs preferred low-elevation habitats (1,300 to 1,600 m), and golden takins mainly inhabited high-elevation areas (1,900 to 2,100 m). Golden takins showed obvious avoidance of roads, with avoidance distance from the road of >300 m. In contrast, Reeves's muntjacs were remarkably abundant within 200 m of the road. For both wild boars and Pere David's rock squirrels, there was no significant difference in RAI among 5 highway ranges. These findings help describe the distribution and activity patterns of these species in Qinling, to monitor their population dynamics, and to develop tailored conservation strategies for the 4 species and sympatric wildlife. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Camera collars reveal macronutrient balancing in free‐ranging male moose during summer.
- Author
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Spitzer, Robert, Ericson, Monica, Felton, Annika M., Heim, Morten, Raubenheimer, David, Solberg, Erling J., Wam, Hilde K., and Rolandsen, Christer M.
- Subjects
- *
WILDLIFE conservation , *MOOSE , *ANIMAL populations , *FORAGING behavior , *FOREST management - Abstract
Understanding how the nutritional properties of food resources drive foraging choices is important for the management and conservation of wildlife populations. For moose (Alces alces), recent experimental and observational studies during the winter have shown macronutrient balancing between available protein (AP) and highly metabolizable macronutrients (total non‐structural carbohydrates [TNC] and lipids). Here, we combined the use of continuous‐recording camera collars with plant nutrient analyses and forage availability measurements to obtain a detailed insight into the food and nutritional choices of three wild moose in Norway over a 5‐day period in summer. We found that moose derived their macronutrient energy primarily from carbohydrates (74.2%), followed by protein (13.1%), and lipids (12.7%). Diets were dominated by deciduous tree browse (71%). Willows (Salix spp.) were selected for and constituted 51% of the average diet. Moose consumed 25 different food items during the study period of which 9 comprised 95% of the diet. Moose tightly regulated their intake of protein to highly metabolizable macronutrients (AP:TNC + lipids) to a ratio of 1:2.7 (0.37 ± 0.002SD). They did this by feeding on foods that most closely matched the target macronutrient ratio such as Salix spp., or by combining nutritionally imbalanced foods (complementary feeding) in a non‐random manner that minimized deviations from the intake target. The observed patterns of macronutrient balancing aligned well with the findings of winter studies. Differential feeding on nutritionally balanced downy birch (Betula pubescens) leaves versus imbalanced twigs+leaves across moose individuals indicated that macronutrient balancing may occur on as fine a scale as foraging bites on a single plant species. Utilized forages generally met the suggested requirement thresholds for the minerals calcium, phosphorus, copper, molybdenum, and magnesium but tended to be low in sodium. Our findings offer new insights into the foraging behavior of a model species in ungulate nutritional ecology and contribute to informed decision‐making in wildlife and forest management. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Establishing large mammal population trends from heterogeneous count data.
- Author
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Pradel, R., Renaud, P.‐C., Pays, O., Scholte, P., Ogutu, J. O., Hibert, F., Casajus, N., Mialhe, F., and Fritz, H.
- Subjects
- *
MAMMAL populations , *WILDLIFE conservation , *WILDLIFE management , *ANIMAL species , *TIME series analysis , *ANIMAL populations - Abstract
Monitoring population trends is pivotal to effective wildlife conservation and management. However, wildlife managers often face many challenges when analyzing time series of census data due to heterogeneities in sampling methodology, strategy, or frequency. We present a three‐step method for modeling trends from time series of count data obtained through multiple census methods (aerial or ground census and expert estimates). First, we design a heuristic for constructing credible intervals for all types of animal counts including those which come with no precision measure. Then, we define conversion factors for rendering aerial and ground counts comparable and provide values for broad classes of animals from an extant series of parallel aerial and ground censuses. Lastly, we construct a Bayesian model that takes the reconciled counts as input and estimates the relative growth rates between successive dates while accounting for their precisions. Importantly, we bound the rate of increase to account for the demographic potential of a species. We propose a flow chart for constructing credible intervals for various types of animal counts. We provide estimates of conversion factors for 5 broad classes of species. We describe the Bayesian model for calculating trends, annual rates of population increase, and the associated credible intervals. We develop a bespoke R CRAN package, popbayes, for implementing all the calculations that take the raw counts as input. It produces consistent and reliable estimates of population trends and annual rates of increase. Several examples from real populations of large African mammals illustrate the different features of our method. The approach is well‐suited for analyzing population trends for heterogeneous time series and allows a principled use of all the available historical census data. The method is general and flexible and applicable to various other animal species besides African large mammals. It can readily be adapted to test predictions of various hypotheses about drivers of rates of population increase. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. Using convolutional neural networks to count parrot nest‐entrances on photographs from the largest known colony of Psittaciformes.
- Author
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Zanellato, Gabriel L., Pagnossin, Gabriel A., Failla, Mauricio, and Masello, Juan F.
- Subjects
- *
ANIMAL population estimates , *CONVOLUTIONAL neural networks , *COLONIAL birds , *ANIMAL populations , *COMPUTER vision - Abstract
Counting animal populations is fundamental to understand ecological processes. Counts make it possible to estimate the size of an animal population at specific points in time, which is essential information for understanding demographic change. However, in the case of large populations, counts are time‐consuming, particularly if carried out manually. Here, we took advantage of convolutional neural networks (CNN) to count the total number of nest‐entrances in 222 photographs covering the largest known Psittaciformes (Aves) colony in the world. We conducted our study at the largest Burrowing Parrot Cyanoliseus patagonus colony, located on a cliff facing the Atlantic Ocean in the vicinity of El Cóndor village, in north‐eastern Patagonia, Argentina. We also aimed to investigate the distribution of nest‐entrances along the cliff with the colony. For this, we used three CNN architectures, U‐Net, ResUnet, and DeepLabv3. The U‐Net architecture showed the best performance, counting a mean of 59,842 Burrowing Parrot nest‐entrances across the colony, with a mean absolute error of 2.7 nest‐entrances over the testing patches, measured as the difference between actual and predicted counts per patch. Compared to a previous study conducted at El Cóndor colony more than 20 years ago, the CNN architectures also detected noteworthy differences in the distribution of the nest‐entrances along the cliff. We show that the strong changes observed in the distribution of nest‐entrances are a measurable effect of a long record of human‐induced disturbance to the Burrowing Parrot colony at El Cóndor. Given the paramount importance of the Burrowing Parrot colony at El Cóndor, which concentrates 71% of the world's population of this species, we advocate that it is imperative to reduce such a degree of disturbance before the parrots reach the limit of their capacity of adaptation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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