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Captive birds in zoological settings often harbor parasites, but little information is available about the potential for free-ranging avifauna to act as a source of infection. This review summarizes the gastrointestinal parasites found in zoo birds globally and in seven common free-ranging avian spe¬cies [mallard (Anas platyrhynchos), Eurasian blackbird (Turdus merula), common starling (Sturnus vulgaris), Eurasian jackdaw (Corvus monedula), house sparrow (Passer domesticus), European robin (Erithacus rubecula), and rock dove (Columba livia)] to identify the overlap and discuss the potential for cross-species transmission. Over 70 references were assessed, and papers spanned over 90 years from 1925 to 2019. A total of 60 studies from 1987 to 2019 met the eligibility cri¬teria. All examined free-ranging avifauna harbored parasite species that were also reported in zoo birds, except for the European jackdaw. Parasites reported in captive and free-ranging birds include nematodes (Capillaria caudinflata, Dispharynx nasuta, Ornithostrongylus quadriradiatus, Strongyloides avium, Syngamus trachea, and Tetrameres fissispina), cestodes (Dicranotaenia coronula, Diorchis stefanskii, Fimbriaria fasciolaris, and Raillietina cesticillus, Sobolevicanthus gracilis), trematode (Echinostoma revolutum), and protozoa (Cryptosporidium baileyi). Although no study effectively proved cross-transmission either experimentally or by genetic analysis, these parasites demonstrate low host specificity and a high potential for parasite sharing. There is potential for parasite sharing whenever determinants such as host specificity, life cycle, and hus¬bandry are favorable. More research should be carried out to describe parasites in both captive and free-ranging birds in zoological settings and the likelihood of cross-infection. Such information would contribute to evidence-based control measures, enhancing effective husbandry and pre¬ventive medicine protocols. [J Adv Vet Anim Res 2020; 7(3.000): 482-500]

A major barrier to advancing ornithology is the systemic exclusion of professionals from the Global South. A recent special feature, Advances in Neotropical Ornithology, and a shortfalls analysis therein, unintentionally followed a long-standing pattern of highlighting individuals, knowledge, and views from the Global North, while largely omitting the perspectives of people based within the Neotropics. Here, we review current strengths and opportunities in the practice of Neotropical ornithology. Further, we discuss problems with assessing the state of Neotropical ornithology through a northern lens, including discovery narratives, incomplete (and biased) understanding of history and advances, and the promotion of agendas that, while currently popular in the north, may not fit the needs and realities of Neotropical research. We argue that future advances in Neotropical ornithology will critically depend on identifying and addressing the systemic barriers that hold back ornithologists who live and work in the Neotropics: unreliable and limited funding, exclusion from international research leadership, restricted dissemination of knowledge (e.g., through language hegemony and citation bias), and logistical barriers. Moving forward, we must examine and acknowledge the colonial roots of our discipline, and explicitly promote anti-colonial agendas for research, training, and conservation. We invite our colleagues within and beyond the Neotropics to join us in creating new models of governance that establish research priorities with vigorous participation of ornithologists and communities within the Neotropical region. To include a diversity of perspectives, we must systemically address discrimination and bias rooted in the socioeconomic class system, anti-Blackness, anti-Brownness, anti-Indigeneity, misogyny, homophobia, tokenism, and ableism. Instead of seeking individual excellence and rewarding top-down leadership, institutions in the North and South can promote collective leadership. In adopting these approaches, we, ornithologists, will join a community of researchers across academia building new paradigms that can reconcile our relationships and transform science. Spanish and Portuguese translations are available in the Supplementary Material.

Darwin’s finches are a classic example of adaptive radiation involving differential use of dietary resources among sympatric species. Here, we apply stable isotope (δ13C, δ15N, and δ2H) analyses of feathers to examine ecological segregation among eight Darwin’s finch species in Santa Cruz Island, Galápagos collected from live birds and museum specimens (1962–2019). We found that δ13C values were higher for the granivorous and herbivorous foraging guilds, and lower for the insectivorous finches. Values of δ15N were similar among foraging guilds but values of δ2H were higher for insectivores, followed by granivores, and lowest for herbivores. The herbivorous guild generally occupied the largest isotopic standard ellipse areas for all isotopic combinations and the insectivorous guild the smallest. Values of δ2H provided better trophic discrimination than those of δ15N possibly due to confounding influences of agricultural inputs of nitrogen. Segregation among guilds was enhanced by portraying guilds in three-dimensional isotope (δ13C, δ15N, and δ2H) space. Values of δ13C and δ15N were higher for feathers of museum specimens than for live birds. We provide evidence that Darwin’s finches on Santa Cruz Island tend to be generalists with overlapping isotopic niches and suggest that dietary overlap may also be more considerable than previously thought.

Introduction:Threats that affect the avian diversity on the Galápagos Islands are increasing. We evaluated threats such as climate change and severe weather, human intrusions and disturbance, biological resource use, invasive and other problematic species, genes and diseases, pollution, geological events and loss of genetic diversity in relation with avian species enlisted in both the international and national (Ecuador) IUCN Red List, which can be used as sentinel species of the ecosystem. Here, the status of the threatened species for the next ten years (present time up to 2028), under two scenarios, including thestatus quoand theavian diversity visionfor the species’ conservation, was assessed.Methods:The conceptual framework of the assessment was envisioned within the existing knowledge and projections of present and future threats to revisit current conservation efforts. Based on this evaluation, a set of management actions coupled with mitigation strategies to address new anthropogenic threats affecting the long-term survival of species in the face of global and regional environmental changes are recommended. Alternative strategies for species conservation, mainly when declining avian populations are susceptible to demographic bottlenecks or risk of extinction and when natural disasters affect ecosystem stability, are also considered.Results:These results should be envisioned as a guide for the evaluation and management of the avian species in the future to be replicated every decade.

We examined population differentiation across a substantial portion of the range of the brown pelican (Pelecanus occidentalis) to assess (1) the genetic distinctness of the Galapagos subspecies (P. o. urinator) and (2) genetic differentiation between subspecies that inhabit the coasts of North and Central America (P. o. californicus and P. o. carolinensis). Birds were sampled from coastal California, coastal Florida, and the Galapagos Islands. Using a 957 bp (bp) fragment of the NADH dehydrogenase subunit 2 (ND2) gene, 661 bp of the mitochondrial control region, and eleven microsatellite loci we characterize population genetic differentiation among 158 brown pelicans. The Galapagos subspecies is genetically distinct from the sampled continental subspecies, possessing a unique ND2 haplotype and unique mitochondrial control region haplotypes. Samples from the two continental subspecies all possessed the same ND2 haplotype and shared four mitochondrial control region haplotypes. Bayesian clustering in STRUCTURE placed the Galapagos subspecies in a distinct genetic group with high probability, but could not differentiate the continental subspecies from one another. Estimates of migration rates from BayesAss indicated substantial migration between continental subspecies, but no migration between the Galapagos subspecies and either continental subspecies. There are clearly two Evolutionarily Significant Units within the range of the brown pelican, which warrants conservation attention. Further investigation should determine how the un-sampled subspecies (P. o. murphyi and P. o. occidentalis) fit into the broader picture.

Penguins are the most threatened group of seabirds after albatrosses. Although penguins are regularly captured in fishing gear, the threat to penguins as a group has not yet been assessed. We reviewed both published and grey literature to identify the fishing gear types that penguins are most frequently recorded in, the most impacted species and, for these susceptible species, the relative importance of bycatch compared to other threats. While quantitative estimates of overall bycatch levels are difficult to obtain, this review highlights that, of the worldís 18 species of penguins, 14 have been recorded as bycatch in fishing gear and that gillnets, and to a lesser extent trawls, are the gear types that pose the greatest threats to penguins. Bycatch is currently of greatest concern for yellow-eyed Megadyptes antipodes (Endangered), Humboldt Spheniscus humboldti (Vulnerable) and Magellanic Spheniscus magellanicus penguins (Near Threatened). Penguins face many threats; reducing bycatch mortality in fishing gear will greatly enhance the resilience of penguin populations to threats from habitat loss and climate change that are more difficult to address in the short term. Additional data are required to quantify the true extent of penguin bycatch, particularly for the most susceptible species. In the meantime, it is crucially important to manage the fisheries operating within known penguin foraging areas to reduce the risks to this already threatened group of seabirds.

Using a fecal flotation technique, we detected three genera of endoparasites in the critically endangered Waved Albatross (Phoebastria irrorata) of Galápagos. These genera were Contracaecum, Tetrabothrius, and Cardiocephaloides. Juvenile albatrosses were more likely to be infected than adults, but we found no effect of sex or mass on infection probability.

Haemosporidian parasites in the genus Plasmodium were recently detected through molecular screening in the Galapagos Penguin (Spheniscus mendiculus). We summarized results of an archipelago-wide screen of 3726 endemic birds representing 22 species for Plasmodium spp. through a combination of molecular and microscopy techniques. Three additional Plasmodium lineages were present in Galapagos. Lineage A–infected penguins, Yellow Warblers (Setophaga petechia aureola), and one Medium Ground Finch (Geospiza fortis) was detected at multiple sites in multiple years. The other 3 lineages were each detected at one site and at one time; apparently, they were transient infections of parasites not established on the archipelago. No gametocytes were found in blood smears of infected individuals; thus, endemic Galapagos birds may be dead-end hosts for these Plasmodium lineages. Determining when and how parasites and pathogens arrive in Galapagos is key to developing conservation strategies to prevent and mitigate the effects of introduced diseases. To assess the potential for Plasmodium parasites to arrive via migratory birds, we analyzed blood samples from 438 North American breeding Bobolinks (Dolichonyx oryzivorus), the only songbird that regularly migrates through Galapagos. Two of the ephemeral Plasmodium lineages (B and C) found in Galapagos birds matched parasite sequences from Bobolinks. Although this is not confirmation that Bobolinks are responsible for introducing these lineages, evidence points to higher potential arrival rates of avian pathogens than previously thought. Linajes Multiples de Parasitos de Malaria Aviar (Plasmodium) en las Islas Galapagos y Evidencia de su Arribo por Medio de Aves Migratorias Resumen Parasitos de la familia Haemosporidia, del genero Plasmodium recientemente fueron detectados por medio de analisis moleculares en el pinguino de las Galapagos (Spheniscus mendiculus). Resumimos los resultados de un analisis, extendido a lo largo del archipielago, de 3726 aves endemicas representando a 22 especies para Plasmodium spp. mediante la combinacion de tecnicas moleculares y de microscopia. Tres linajes adicionales de Plasmodium estuvieron presentes en las Galapagos. El linaje A infecto pinguinos, individuos Setophaga petechia aureola y a un individuo de Geospiza fortis en sitios multiples y en varios anos. Los otros 3 linajes fueron detectados cada uno en un sitio y en un tiempo especifico; aparentemente, fueron infecciones transitorias de parasitos no establecidos en el archipielago. No se encontraron gametocitos en los frotis de sangre de individuos infectados; por esto, las aves endemicas de las Galapagos pueden ser hospederos finales de estos linajes de Plasmodium. Determinar cuando y como llegaron los parasitos y los patogenos a las Galapagos es clave para desarrollar estrategias de conservacion para prevenir y mitigar los efectos de las enfermedades introducidas. Para evaluar el potencial de llegada de Plasmodium en aves migratorias, analizamos muestras de sangre de 438 Dolichonyx oryzivorus en epoca reproductiva. Esta ave es la unica canora que migra regularmente a traves de las Galapagos. Dos de los linajes efimeros de Plasmodium (B y C) que se hallaron en las aves de las Galapagos coincidieron con secuencias de parasitos del ave canora. Aunque esto no confirma que Dolichonyx oryzivorus sea responsable de introducer estos linajes, la evidencia apunta a un potencial mas alto de tasas de llegada de patogenos aviares de lo que se pensaba previamente.

El Niño Southern Oscillation events have been associated with large fluctuations in seabird and landbird populations of the Galápagos Islands. We reveal different effects of climatic variation on the abundance and distribution of a waterbird, as illustrated by the flamingos Phoenicopterus ruber living in saline coastal lagoons of the arid Galápagos environment. Using time series analyses [autoregressive integrated moving average (ARIMA)] to model the temporal variations in abundance, we found significant correlations between rainfall, lagoon water level (LWL), lagoon temperature and flamingo abundance. Although these variables were good predictors of flamingo abundance, they explained < 50% of the variance in monthly counts. During the strong El Niño event of 1982-1983, extreme rainfall resulted in an increase in LWLs (> 300 mm above the long-term mean) and a record decline in flamingo numbers. Monthly abundance of flamingos was lower, on average, during the rainy season (between January and May) when LWLs were above their seasonal mean. Flamingo abundance at the two lagoons on Isabela Island and those at 'all other lagoons' in the Archipelago showed a significant negative correlation. We infer that moderate reductions in the abundance of flamingos in the rainy season and significant temporal declines during El Niño events are explained by movements between lagoons within the Archipelago rather than by mortality. This illustrates the general principle that climate change may, without directly affecting population sizes, prompt adaptive behavioural changes with the potential to affect population biology.

0-DDE Health risk abstract We characterize for the first time the presence of DDT and its metabolites in tropical Galapagos sea lions (Zalophus wolleabeki). P DDT concentrations in Galapagos sea lion pups sampled in 2005 and 2008 ranged from 16 to 3070 lg/kg lipid. Concentrations of P DDT in pups in 2008 averaged 525 lg/kg lipid and were 1.9 times higher than that (281 lg/kg lipid) detected in pups in 2005. These concentrations are lower than those reported in many pinnipeds elsewhere, comparable to those in Hawaiian monk seals, and higher than those in southern elephant seals. The health risk characterization showed that 1% of the male pups exceeded the p,p 0-DDE toxic effect concentration associated with anti-androgenic effects reported in rats. The findings provide preliminary guidance on the relationship between DDT use and ecological impacts, serving as a reference point against which possible future impact of tropical DDT use can be assessed.

Dichlorodiphenyltrichloroethane (DDT) is an effective and relatively cheap anti-malaria pesticide which has saved human lives, but also brought Northern wildlife species to the brink of extinction due to its persistence, bioaccumulation in the food-web, and hormone-mimicking characteristics (Carson 1962; Vallack et al. 1998; UNEP 2001; ATSDR 2002; Blus 2003; WHO 2006; Colborn and Carroll 2007; Van den Berg 2008). Thirty-two years after its ban in the US and its inclusion on Schedule 2 of the UN Stockholm Convention on Persistent Organic Pollutants (POPs) because of its damaging health effects in human and wildlife populations (UNEP 2001; ATSDR 2002; WHO 2006; Vallack et al. 1998; Colborn and Carroll 2007; Blus 2003), the WHO has recommitted to the use of the malaria-fighting pesticide DDT in tropical countries because of an increase in malaria cases in tropical countries (e. g., Peru, Bolivia, Paraguay, Brazil, and African nations), where DDT use was halted or low application rates were used (Van den Berg 2008; WHO 2006; Roberts et al. 1997, 2000). Although evolutionary adaptation of the malaria vector has triggered insecticide resistance to DDT (Denholm et al. 2002), the return to an increased reliance on DDT use is testament to DDT’s effectiveness in combating malaria at a low cost. Large volumes of DDT (i.e., 4,000–5,000 tonnes of active ingredient per year) were used in India and Africa countries to overcome the malaria crisis (Van den Berg 2008). However, 50 years of research on DDT in the temperate and arctic regions of the Northern hemisphere have documented that human health benefits go hand in hand with detrimental effects on wildlife populations (Carson 1962; De Guise et al. 1998; Lahvis et al. 1995; Guillette et al. 1994; Blus 2003;). Since wildlife provides life support, sustenance, and economic opportunities through harvesting and ecotourism in many developing tropical countries, the health of wildlife cannot be viewed in isolation of human health. A balance needs to be struck between health benefits and health risks of DDT use. This requires an understanding of the fate, trends, and dose–response relationship for DDT in tropical wildlife. Such information does currently not exist and monitoring and source control programs that can help to document this relationship are as absent in tropical countries to date as they were in the Western world when DDT was first used in the 1940s and 1960s (Roberts et al. 2000; ATSDR 2002; Blus 2003; Colborn and Carroll 2007; Van den Berg 2008). From a global perspective, the protection of coastal food webs from contamination by chemical pollutants is critical to the long term conservation of the biodiversity and native inhabitants residing in unique places of the Earth, including UNESCO Global Heritage sites such as the Galapagos Islands. Coastal waters that are contaminated with persistent chemicals and pathogens can lead to human illness and adverse health, reduced fisheries quality and quantity, and impacts of the health of marine wildlife. This had obvious social and economic consequences. Conversely, coastal waters that are protected from chemical pollutants provide for an abundance of clean fisheries products and wildlife, and essential foundation for the well-being of the local biodiversity, human residents and the ecotourism sector. At the top of the marine-coastal food chain, marine mammals can provide an “integrated” overview of ecosystem health. As aquatic animals, they are also vulnerable to infection by pathogens of terrestrial origin. By documenting the presence of chemical pollutants in this species, we are able to deliver science-based advice to conservationists, managers, regulators, and stakeholders, on the implementation of best management practices. Equivalent to the role of killer whales as global sentinels of pollution in the Northeastern Pacific, the Galapagos sea lion has recently been used as a sentinel of marine pollution and a key indicator of the ecosystem functioning and oceanic-coastal environmental health in Galapagos Islands. Therefore, this synopsis aims to synthesize our recent findings on DDT contamination in Galapagos sea lions and its use as a sentinel-model species of environmental pollution by POPs.

Some species of coccinellids exude a fluid that contains an alkaloid which can be toxic to vertebrates that ingest them. Because of this, before introducing Rodolia cardinalis to the Galapagos Islands as a biological control agent for the invasive scale insect, Icerya purchasi , it was considered necessary to determine whether it is toxic to birds. In this study, experiments were carried out with two common, insectivorous finches that are endemic to the Galapagos Islands; Camarhynchus parvulus (12 individuals) and Geospiza fuliginosa (16 individuals). Finches were maintained in captivity for 12–18 days. This period was divided into three phases: adaptation, experimental, and observation. During the experimental phase, test individuals, in addition to their regular diet, were fed 0.15 g portions of larvae or adults of R. cardinalis on alternate days over four days. The control group were fed 0.15 g of Asciodes quietalis abdomens in place of R. cardinalis . Symptoms of toxicity (mortality, deterioration, critical weight loss) from feeding on R. cardinalis were not observed in either species while in captivity, but birds avoided or rejected beetles indicating that they were distasteful. Finches regurgitated a higher number of larvae than adult beetles suggesting that larvae were less palatable than adults. Although long-term monitoring was not possible, results suggest that at least two species of finch will be unaffected by the release of R. cardinalis into the Galapagos Islands.

The presence of avian pox in endemic birds in the Galapagos Islands has led to concern that the health of these birds may be threatened by avipoxvirus introduction by domestic birds. We describe here a simple polymerase chain reaction-based method for identification and discrimination of avipoxvirus strains similar to the fowlpox or canarypox viruses. This method, in conjunction with DNA sequencing of two polymerase chain reaction-amplified loci totaling about 800 bp, was used to identify two avipoxvirus strains, Gal1 and Gal2, in pox lesions from yellow warblers (Dendroica petechia), finches (Geospiza spp.), and Galapagos mockingbirds (Nesomimus parvulus) from the inhabited islands of Santa Cruz and Isabela. Both strains were found in all three passerine taxa, and sequences from both strains were less than 5% different from each other and from canarypox virus. In contrast, chickens in Galapagos were infected with a virus that appears to be identical in sequence to the characterized fowlpox virus and about 30% dif- ferent from the canarypox/Galapagos group viruses in the regions sequenced. These results in- dicate the presence of canarypox-like viruses in endemic passerine birds that are distinct from the fowlpox virus infecting chickens on Galapagos. Alignment of the sequence of a 5.9-kb region of the genome revealed that sequence identities among Gal1, Gal2, and canarypox viruses were clustered in discrete regions. This indicates that recombination between poxvirus strains in com- bination with mutation led to the canarypox-like viruses that are now prevalent in the Galapagos.

The role of disease in regulating populations is controversial, partly owing to the absence of good disease records in historic wildlife populations. We examined birds collected in the Galapagos Islands between 1891 and 1906 that are currently held at the California Academy of Sciences and the Zoologisches Staatssammlung Muenchen, including 3973 specimens representing species from two well-studied families of endemic passerine birds: finches and mockingbirds. Beginning with samples collected in 1899, we observed cutaneous lesions consistent with Avipoxvirus on 226 (6.3%) specimens. Histopathology and viral genotyping of 59 candidate tissue samples from six islands showed that 21 (35.6%) were positive for Avipoxvirus, while alternative diagnoses for some of those testing negative by both methods were feather follicle cysts, non-specific dermatitis, or post mortem fungal colonization. Positive specimens were significantly nonrandomly distributed among islands both for mockingbirds (San Cristobal vs. Espanola, Santa Fe and Santa Cruz) and for finches (San Cristobal and Isabela vs. Santa Cruz and Floreana), and overall highly significantly distributed toward islands that were inhabited by humans (San Cristobal, Isabela, Floreana) vs. uninhabited at the time of collection (Santa Cruz, Santa Fe, Espanola), with only one positive individual on an uninhabited island. Eleven of the positive specimens sequenced successfully were identical at four diagnostic sites to the two canarypox variants previously described in contemporary Galapagos passerines. We conclude that this virus was introduced late in 1890′s and was dispersed among islands by a variety of mechanisms, including regular human movements among colonized islands. At present, this disease represents an ongoing threat to the birds on the Galapagos Islands.

Necropsy findings were reviewed from wild birds submitted to the Charles Darwin Research Station, Santa Cruz Island, Galapagos Archipelago between 2004 and 2006. One hundred and ninety cases from 27 different species were submitted, and 178 of these cases were evaluated grossly or histologically. Trauma and trauma-related deaths (n=141) dominated necropsy submissions. Infectious causes of avian mortality included myiasis due to Philornis sp. (n=6), avian pox (n=1), and schistosomosis (n=1).