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This paper investigates the dynamics of a new discrete form of the classical continuous Rosenzweig–MacArthur predator–prey model and the biological implications of the dynamics. The discretization method used here is to modify the continuous model to another with piecewise-constant arguments and then to integrate the modified model, which is quite different from the traditional Euler discretization method. First, the existence and local stability of fixed points have been thoroughly discussed. Then, all codimension-1 bifurcations have been studied, including the transcritical bifurcations at the trivial fixed point and the boundary fixed point, and the Neimark–Sacker bifurcation at the unique positive fixed point. Furthermore, it is proved that there are no codimension-2 bifurcations. Finally, the control of the bifurcations is studied. Regarding the biological significance, we have considered the following four aspects: When no harvesting effort is applied to both predators and prey, it is observed that providing more resources to the prey species leads to predator extinction, causing the ecosystem to lose stability. This implies that the paradox of enrichment occurs. When predators are harvested, the system exhibits the hydra effect, i.e. increasing the harvesting effort on predators will lead to an increase in the mean population density of predators. When the prey is harvested, numerical examples indicate that increasing the harvesting effort initially reduces prey density. Upon reaching the bifurcation point, prey density stabilizes while the predator density continues to decline. When both prey and predators are harvested, the biological significance is similar to the previous case. The outcomes of this paper have significant theoretical meaning in the study of population ecology. By MATLAB, the bifurcation diagrams, maximal Lyapunov exponent diagrams, phase portraits and mean population density curves are plotted. Numerical simulations not only show the correctness of the theoretical findings but also reveal many new and interesting dynamics. [ABSTRACT FROM AUTHOR]

The editorial "Ecology of Freshwater Fish" discusses the journal's commitment to research assessment, open access publishing, and changes in submission requirements. The journal focuses on basic ecology of freshwater fishes and conservation, with an emphasis on pure, fundamental science. Special issues, top cited papers, and information on editorial practices and board members are also provided. The journal encourages equity, diversity, and inclusion in its editorial board and welcomes applications from interested scientists. [Extracted from the article]

IntroductionMethodsKey results and conclusionsLocated on the extreme edge of its range, Didymodon cordatus is exceptionally rare in Britain and is considered a priority for conservation. In the present study, its current population status and ecology were investigated.All previously known locations for the species were surveyed, plus other potential locations nearby. Abundance was measured in terms of ‘individual-equivalents’, defined as an occupied 1  m grid cell. Geographical coordinates of each individual-equivalent were recorded with a GPS unit. Habitat and community composition were recorded by relevés.Didymodon cordatus continues to survive at its only location in Britain, at Saunton Down, North Devon, including a length of nearby coastal cliff from where it has been known since 1916 and an adjacent roadside bank from where it has been known since 1962. No other locations were found. It occupies open, dry, calcareous and thermophilous habitat, together with a diverse assemblage of other acrocarpous mosses. While the species is particularly associated with loess soils in continental Europe, at Saunton Down it is closely associated with soft, calcareous sandstone and thin, overlying sandy soil. Natural erosion is an important part of the occupied habitat, maintaining early successional habitat patches suitable for colonisation. A total of 102 individual-equivalents were found, and it is estimated that the entire population at Saunton Down comprises 250–1000 individual-equivalents. The habitat is generally in favourable condition and the population appears to be secure, although the species will remain vulnerable to extinction in Britain because of its extreme rarity. [ABSTRACT FROM AUTHOR]

Background: Five species of the Phortica genus (Diptera: Drosophilidae) are known in Europe and the Middle East. Among these, Phortica variegata and Phortica okadai are better known for their role as vectors of the zoonotic eyeworm Thelazia callipaeda. Other species, such as Phortica semivirgo and Phortica oldenbergi, have been studied less. Given the paucity of data about these Phortica spp. vectors, we explored the population dynamics and ecology of Phortica spp. in an area highly endemic for T. callipeada (Manziana, Rome, Central Italy). Methods: Phortica spp. flies were collected over a 3-year period (2018–2020) during their active season (April–October) with a sweep net while hovering around fermenting fruits or a human operator acting as baits. Collected flies were morphologically identified and tested for a T. callipeada infection and for the presence of Wolbachia, by polymerase chain reaction (PCR). Population dynamics of species collected was associated to environmental drivers through generalized additive models. Results: Of the 5564 flies collected, 90.8% were P. variegata, 9.1% were P. oldenbergi, 0.05% were P. semivirgo, and one specimen was P. okadai. Only P. variegata scored molecularly infected with T. callipeada throughout the 3-year sampling period (1.8%). Phortica oldenbergi, observed consistently during the entire sampling period, exhibited a marked preference for fruit traps, contrasting with the lachryphagous activity of P. variegata. Analysis of environmental drivers of P. oldenbergi and P. variegata population dynamics indicated temperature, wind speed, and pressure as significant factors. In addition, Wolbachia pipientis endosymbiont was detected in P. oldenbergi and P. okadai. Conclusions: For the first time, this study analysed several ecological aspects of Phortica species coexisting in a T. callipeada endemic area, highlighting different behaviors in the same environment and their vectorial role. Notably, this is also the first report of the presence of P. oldenbergi in Italy and P. okadai in Europe, underscoring the importance of extensive sampling for detecting potential vectors and alien species with direct implications for vector-borne disease epidemiology. [ABSTRACT FROM AUTHOR]

Identifying the mechanisms underlying the persistence of rare species has long been a motivating question for ecologists. Classical theory implies that community dynamics should be driven by common species, and that natural selection should not allow small populations of rare species to persist. Yet, a majority of the species found on Earth are rare. Consequently, several mechanisms have been proposed to explain their persistence, including negative density dependence, demographic compensation, vital rate buffering, asynchronous responses of subpopulations to environmental heterogeneity, and fine‐scale source‐sink dynamics. Persistence of seeds in a seed bank, which is often ignored in models of population dynamics, can also buffer small populations against collapse. We used integral projection models (IPMs) to examine the population dynamics of Oenothera coloradensis, a rare, monocarpic perennial forb, and determine whether any of five proposed demographic mechanisms for rare species persistence contribute to the long‐term viability of two populations. We also evaluate how including a discrete seed bank stage changes these population models. Including a seed bank stage in population models had a significantly increased modeled O. coloradensis population growth rate. Using this structured population model, we found that negative density‐dependence was the only supported mechanism for the persistence of this rare species. We propose that high micro‐site abundances within a spatially heterogeneous environment enables this species to persist, allowing it to sidestep the demographic and genetic challenges of small population size that rare species typically face. The five mechanisms of persistence explored in our study have been demonstrated as effective strategies in other species, and the fact that only one of them had strong support here supports the idea that globally rare species can employ distinct persistence strategies. This reinforces the need for customized management and conservation strategies that mirror the diversity of mechanisms that allow rare species persistence. [ABSTRACT FROM AUTHOR]

Hipposideros spp. are insectivorous bats and karst cave dwellers. This study aimed to study the roosting ecology, reproduction, and population fluctuations of three species H. diadema, H. larvatus, and H. ater in Gunung Sewu Karst region, Indonesia. Age and reproductive status of individuals were identified and analyzed using a combination of forearm length (FA) and body mass grades (W). Multiple regression analysis was used to determine the correlation between population size, rainfall and population structure based on FA, reproductive status, and W. Crude birth rate (CBR) and general fertility rate (GFR) were used to determine the population’s birth rate and female fertility. The results showed that the population of the three Hipposideros species were quite stable over the year with a peak in January which classified them as monoestrous, with mating, pregnancy, and lactation occurring once a year with no delay between mating and pregnancy. Pregnancy lasted 8–12 weeks and lactation 4–5 weeks. The population structure of the three species tended to be stable over the year. The CBR and GFR values can be used for rapid assessment guidelines in an area. [ABSTRACT FROM AUTHOR]

Population ecology theory is replete with density-dependent processes. However, trait-mediated or behavioral indirect interactions can both reinforce or oppose density-dependent effects. This paper presents the first two species competitive ODE and PDE systems, where the non-consumptive behavioral fear effect and the Allee effect, a density-dependent process, are both present. The stability of the equilibria is discussed analytically using the qualitative theory of ordinary differential equations. It is found that the Allee effect and the fear effect change the extinction dynamics of the system and the number of positive equilibrium points, but they do not affect the stability of the positive equilibria. We also observe standard co-dimension one bifurcation in the system by varying the Allee or fear parameter. Interestingly, we find that the Allee effect working in conjunction with the fear effect can bring about several dynamical changes to the system with only fear. There are three parametric regimes of interest in the fear parameter. For small and intermediate amounts of fear, the Allee + fear effect opposes dynamics driven by the fear effect. However, for large amounts of fear the Allee + fear effect reinforces the dynamics driven by the fear effect. The analysis of the corresponding spatially explicit model is also presented. To this end, the comparison principle for parabolic PDE is used. The conclusions of this paper have strong implications for conservation biology, biological control as well as the preservation of biodiversity. [ABSTRACT FROM AUTHOR]

The banana mealybug Pseudococcus elisae Borchsenius (Hemiptera: Coccomorpha: Pseudococcidae) is a pest of economic importance in Cameroon that requires effective control practices, especially after the routinely used chlorpyrifos insecticide was banned in 2019. For effective mealybug control, it is imperative to understand their ecology in relation to banana growth stages and climate‐induced seasonal variations. Therefore, the influence of climatic variables and banana growth stages on a spatio‐temporal distribution of mealybugs in Esuke and Benoe banana plantations of the Cameroon Development Corporation in Tiko was assessed.A 60‐ha area was mapped in each plantation and divided into 12 plots of 5 ha each, which were further sub‐divided into four quadrants of 1.25 ha. A total of 10 banana suckers, 10 pre‐flowering, 10 flowering and 10 bunchy plants were sampled per quadrant.Monthly mealybug population dynamics were assessed across 2 years in 2021 and 2022 on lower or upper pseudostem, leaves and banana bunches.Significant yearly and monthly mealybug population variation on banana plants were observed, with more mealybugs in 2022 than 2021, and two monthly mealybug peaks in February and November (p < 0.001). Mealybug population was higher on banana bunches and lower or upper pseudostem than on leaves (p < 0.001). Mealybugs preferred bunchy plants than suckers or pre‐flowering and flowering plants, and exhibited clumped distribution with Taylor aggregation index (b) greater than one (p < 0.001). A simple linear regression revealed strong positive effects of high temperature on mealybug population ecology, while relative humidity and rainfall had inverse effects on the population of mealybug.These highlight the dynamics of banana mealybug population ecology under variable climatic conditions and banana growth stages, which provides valuable baseline information to facilitate developing effective control strategies for mealybugs in banana plantations. [ABSTRACT FROM AUTHOR]

In eastern Spain, Bonelli's eagle (Aquila fasciata) abundance has declined almost 50% in the last 25 years and, consequently, the species is listed as regionally endangered. Therefore, the aim of this study is to report the mortality causes of territorial breeding Bonelli's eagles, including the spatial and temporal patterns, and to assess the effects on population dynamics. From 2015–2023, we tracked 60 Bonelli's eagles via global positioning system‐global system for mobile communications (GPS‐GSM) telemetry; 33 of the eagles died (median survival time = 1,519 days). Survival did not differ in relation to sex, age at capture (subadult vs. adult birds), breeding site (coastland vs. inland territories), or transmitter's model. One‐year probability of survival (95% CI) was 0.716 (0.607–0.845); 2‐year survival was 0.640 (0.524–0.781); and 3‐year survival was 0.581 (0.464–0.729). Anthropogenic mortality (66.7% of cases) prevailed over natural (27.3%) and unknown causes (6.0%). Causes of mortality were intra‐ and interspecific predation (24.2% of cases), electrocution (18.2%), poisoning (15.1%), collision with power lines (9.1%), shooting (9.1%), drowning (9.1%), collision with other man‐made infrastructure (6.1%), and disease (3.0%). Deaths were most frequent during the early breeding season. Only 2 (6.1%) of 33 deaths recorded occurred within a protected area. Natural causes of mortality were more frequent away from the Mediterranean coast. In contrast, anthropogenic deaths were more frequent near the Mediterranean coast, where human population density is high. We estimated that probability of extirpation of the species in our study area is 17.8% in the next 50 years and 99.2% in 100 years. Nonetheless, a small reduction in adult mortality by ≥15% could prevent extirpation in the next 50 years. Therefore, actions to reduce adult mortality are urgently needed to preserve the Bonelli's eagle in eastern Spain. [ABSTRACT FROM AUTHOR]

Bioerosion plays a crucial factor in shaping the structure and function of coral reef ecosystems, with bioeroders actively altering both the physical and ecological dynamics of coral substrates. Despite their importance, studying internal bioeroders in corals presents significant challenges owing to their cryptic nature within the skeletal structures. Additionally, invasive methods are often required to reveal the subtle and microscopic bioerosive alterations they induce in calcium carbonate substrates. Here, we demonstrate the effectiveness of high-resolution micro-computed tomography (mCT) in quantifying the abundance, size, distribution, and growth directions of coral bioeroders such as cryptic calcareous bivalves in the northern Red Sea. We scanned three coral species inhabited by bioeroders, followed by the utilization of three-dimensional image analysis software to identify, count, and measure each bivalve within the coral skeleton, along with quantifying boring cavity volumes. We revealed that mCT captures small boring cavities (< 1mm), providing more accurate abundance estimates of live and dead boring bivalves than the skeleton decalcification technique, with the added benefits of being rapid and non-destructive in contrast to traditional methods. Furthermore, measurements of empty cavity volumes enabled the estimations of the contribution of bioeroders to the overall coral skeletal porosity. Overall, our study highlights mCT as a practical and effective tool for studying cryptic coral bioeroders, providing novel ecological insights into bioeroder population ecology and coral-bioeroder interactions. [ABSTRACT FROM AUTHOR]

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Long‐term genetic studies of wild populations are very scarce, but are essential for connecting ecological and population genetics models, and for understanding the dynamics of biodiversity. We present a study of a wild wheat population sampled over a 36‐year period at high spatial resolution. We genotyped 832 individuals from regular sampling along transects during the course of the experiment. Genotypes were clustered into ecological microhabitats over scales of tens of metres, and this clustering was remarkably stable over the 36 generations of the study. Simulations show that it is difficult to determine whether this spatial and temporal stability reflects extremely limited dispersal or fine‐scale local adaptation to ecological parameters. Using a common‐garden experiment, we showed that the genotypes found in distinct microhabitats differ phenotypically. Our results provide a rare insight into the population genetics of a natural population over a long monitoring period. [ABSTRACT FROM AUTHOR]

We address the linear eigenvalue problem associated with reaction-diffusion models for patchy linear domains with any finite number of unique patches. Interface conditions between adjacent patches may be chosen independently to accurately reflect organism behavior. We show that there exists a real principal eigenvalue with a corresponding non-negative eigenfunction that is non-zero interior to the domain. We demonstrate that our model is a generalization of several existing two-patch models. We consider simple three- and four-patch landscapes representing fragmented reserves to illustrate how our model can be used to analyze population persistence, spatial distribution, and migration dynamics. Fragmented landscapes with increased heterogeneity capture migration dynamics not found in landscapes with only two patch types, such as favorable habitat patches that experience net immigration. Conditions for the existence and non-existence of zero-flux conditions interior to three-patch systems are shown, which provide insight to the location of sources and direction(s) of migration. • Principal eigenvalues are studied for patchy domain problems, and corresponding eigenfunctions are positive on the interior. • An implicit equation is used to obtain numerical solutions to eigenvalue problems on previously intractable patchy domains. • Conditions are derived for the existence of extrema for principal eigenfunctions. • Results are used to simulate different landscapes with fragmented reserves. • Predictions are made for migration across landscapes, including when favorable patches might receive net immigration. [ABSTRACT FROM AUTHOR]

In the context of looming global biodiversity loss, effective species detection represents a critical concern for ecological research and management. Environmental DNA (eDNA) analysis, which refers to the collection and taxonomic identification of genetic fragments that are shed from an organism into its surroundings, emerged approximately 15 years ago as a sensitive tool for species detection. Today, one of the frontiers of eDNA research concerns the collection and analysis of genetic material in dust and other airborne materials, termed airborne eDNA analysis. As the study of airborne eDNA matures, it is an appropriate time to review the foundational and emerging studies that make up the current literature, and use the reviewed literature to summarize, synthesize, and forecast the major challenges and opportunities for this advancing research front. Specifically, we use the "ecology of eDNA" framework to organize our findings across the origin, state, transport, and fate of airborne genetic materials in the environment, and summarize what is so far known of their interactions with surrounding abiotic and biotic factors, including population and community ecologies and ecosystem processes. Within this work we identify key challenges, opportunities, and future directions associated with the application of airborne eDNA development. Lastly, we discuss the development of applications, partnerships, and messaging that promote development and growth of the field. Together, the broad potential of eDNA analysis and the rate at which research is accelerating in this field suggest that the sky's the limit for airborne eDNA science. [ABSTRACT FROM AUTHOR]

It is commonly recognized that predation and the risk of predation can have profound effects on behaviors and population ecology of prey. Comparatively, little attention has been paid to the trade-offs hosts make to manage the risk of parasitism, but there is evidence that hosts make behavioral trade-offs to avoid parasitism in ways that resemble those made by prey animals under the risk of predation. Mosquitoes are common hematophagous ectoparasites which parasitize a wide range of vertebrates, resulting in blood loss, distraction, and disease transmission. Many hosts engage in defensive behaviors to repel or kill mosquitoes and these behaviors likely come at the expense of activities such as foraging and vigilance for predators. We placed a mosquito attractant (BG-Sweetscent) and repellant (allethrin) near artificial foraging patches in areas where mosquitoes were common and measured the amount of grain left after a night of foraging (giving-up density) to investigate whether mosquitoes influenced Cotton Mouse (Peromyscus gossypinus) foraging. We predicted that in patches with mosquito attractants, mosquito harassment would cause mice to engage in defensive behaviors which would distract or deter them from foraging, resulting in less grain consumption relative to control patches. Conversely, we predicted that in mosquito-repellent patches, mice would experience less harassment, resulting in more grain consumption. Indoor arena trials found no evidence that the mosquito treatments influenced cotton mouse behavior in the absence of mosquitoes. However, we found no evidence that mosquito treatments affected giving-up densities. [ABSTRACT FROM AUTHOR]

Background: Rising health care costs and consequent increases inMedicare reimbursements have led tomany payment reforms over the years. Implementation of the prospective payment system (PPS) for hospitals in 1983 incentivized hospitals to either purchase skilled nursing facilities (SNFs) or utilize their excess capacity to establish one within the hospital. With PPS reimbursement being applied to SNFs in 1998, prior monetary incentives for hospitals to own an SNF disappeared. However, despite the reduction in numbers, many hospitals continued to operate their hospitalbased skilled nursing facilities (HBSNFs). Purpose: This study examines the organizational andmarket-level factors associated with the survival of HBSNFs using the population ecology of organizations framework. Methodology: Using American Hospital Association survey data, event histories of all U.S. acute care hospitals with an open HBSNF in 1998 were plotted to examine if a hospital closed its HBSNF during a 22-year period (1998-2020). The primary independent variables included hospital size, ownership, totalmargin, market competition, andMedicare Advantage penetration. The independent and control variableswere lagged by 1 year. Cox regressionswere conducted to estimate the hazard ratios capturing the risk of HBSNF closure. Results: The results showed that HBSNFs located in large, not-for-profit hospitals and those operating in less competitive markets had greater odds of surviving. Practice Implications: The HBSNF administrators of small, for-profit hospitals and those operating in highly competitive markets could utilize the findings of this study to judiciously allocate slack resources to theirHBSNFs to keep those open given the current emphasis on continuity of care by regulatory bodies. [ABSTRACT FROM AUTHOR]

As sperm whales are important predators that control energy flux in the oceans, changes in their population can be used as a sentinel to measure of ecosystem health. The present study conducted a sperm whale survey of the eastern Midriff Islands Region in the Gulf of California over the course of nine years, recording sightings and collecting photographs of the fluke of sperm whale individuals. A photo-identification catalog was compiled, while individual recapture data were used to estimate the population size in the central portion of the Gulf of California, using a Jolly-Seber POPAN open population model. The results obtained show a yearly population of between 20 and 167 sperm whales, with a super population of 354 sperm whales observed between 2009 and 2015. However, from 2016 to 2018, no sightings of the species were recorded, which coincides with the decline observed in landings of their main prey, the jumbo squid, in the region. General additive model conducted on sperm whale sightings per unit of effort vs jumbo squid landings obtained an adjusted R2 of 0.644 and a deviance explained of 60.3%, indicating a good non-linear relationship between sightings of this odontocete and its prey availability. This evidence suggests that sperm whales departed the region between 2016 and 2018, due to a documented fishery collapse alongside changes of their main prey into its small phenotype, possibly as the result of increase warming conditions in surface and subsurface waters in the Gulf of California in the last three decades. [ABSTRACT FROM AUTHOR]

The recovery of mammalian species in the US Midwest through natural recolonization constitutes a conservation success story, yet management remains challenging due to many unknowns related to population dynamics and numeric trends. Abundance is a critical parameter for management decisions, and estimating the density and abundance of elusive species, such as terrestrial carnivores, remains challenging despite recent technological advances. In this study, we evaluated density and abundance of a recovering carnivore species, the bobcat (Lynx rufus) in two areas of Ohio using non‐invasive DNA from scat. The target areas in eastern and southern Ohio have been shown to have uneven dynamics and recolonization success and we expected that this would be reflected in differences in density and abundance. We collected 298 bobcat scats between July 2018 and April 2019 on 150 km of repeated transects. Of these, 102 scats were successfully genotyped, and 55 individuals were identified (33 in eastern Ohio and 22 in southern Ohio). Using Spatially Explicit Capture–Recapture models, we estimated 18.9 ± 4.1 and 10.9 ± 2.7 bobcats/100 km2 in eastern and southern Ohio study areas, respectively. Our results support prior telemetry data which indicated that bobcats in eastern Ohio had smaller home‐ranges than bobcats in southern Ohio, and thus could support a higher density of individuals. The higher densities were similar to other eastern US populations and are much higher than other Midwestern recovering populations. Our results provide a snapshot of the population status and can be used to determine sustainable management strategies for Ohio's bobcat population. [ABSTRACT FROM AUTHOR]

Habitat loss and fragmentation have caused declines in the abundance and distribution of butterflies, particularly habitat specialists. The Chequered Skipper, Carterocephalus palaemon, has been extinct in England since 1976 after declining from the 1940s predominantly due to changes in woodland management including afforestation and the decline in traditional coppice management. To enable C. palaemon to flourish again, this species was reintroduced from Belgium to England in 2018 with the aim of establishing a resident breeding population. Here, we report on the recent reintroduction, outlining the reintroduction method used, the establishment status of the species in England, the clinical health of reintroduced individuals, and post-release monitoring results. Furthermore, we assess the habitat suitability of sites around the original release site to determine which were similar to the current re-location site and could be used for future reintroductions, and to aid the targeting of further management to increase habitat suitability. Since 2018, 128 Chequered Skipper butterflies have been reintroduced from Belgium to Rockingham Forest in England. Health examinations demonstrated that individuals were healthy, and this in part resulted in the population establishing at the first release site and the area of occupancy increasing each year to 2022. However, the reintroduced population has yet to naturally colonise other areas within Rockingham Forest and therefore is not yet a functioning metapopulation. Despite the project still being in its infancy, we are able to report on a successful five years. Implications for insect conservation: Rigorous scientific research has provided the evidence to support reintroductions, and will continue to be used to ensure the ecology and population dynamics of this species is sufficiently understood so that Chequered Skipper populations can thrive again in England. [ABSTRACT FROM AUTHOR]

The Sooty Shearwater (Ardenna grisea) is a species facing global decline, nesting on southern hemisphere islands, and migrating to the northern hemisphere during the non-breeding season. Historical groundwork on Wollaston Island in Chile suggested a possible dispersion of breeding grounds along the seaward fringe of the Fuegian islands, including Isla de los Estados. Recent records ranked the species as the second most abundant during the summer near Isla de los Estados, emphasizing the need for continued exploration to locate and understand the potential breeding site on the island. This study confirms the species ́ breeding presence on Isla de los Estados in the Fuegian archipelago, Argentina. Additionally, we present a preliminary evaluation of its habitat utilization. Active burrows were found along the northern coast of the island on slopes with dense, stumpy subantarctic forests and beneath or alongside rocky outcrops overlooking the coast. Future research should aim at estimating the total population for Isla de los Estados, explore habitat use, and gain insights into the year-round distribution of sooty shearwaters at sea for formulating effective conservation strategies. [ABSTRACT FROM AUTHOR]

The protobranch Aequiyoldia eightsii is one of the most common bivalves in Antarctica and for the first time, its population structure was studied in Admiralty Bay, an Antarctic Specially Managed Area (ASMA), to establish a baseline for future monitoring. Density, size structure, length–weight relationship, condition index, and shell morphometry were evaluated at the shallow coastal zone of the bay. High abundance values of A. eightsii were related to sites with greater contributions of mud particles and total organic carbon contents in the sediment, while the condition indexes were higher in Martel Inlet, possibly due to higher food availability. Individuals obtained from gravel-rich sediments were significantly larger than compressed, while rounded forms were observed in sandy and muddy bottoms of the bay. Positive allometric growth was reported in most sites, except Botany Point, where specimens presented an isometric growth. The results demonstrated that the sediment composition and its organic content influence the population structure of A. eightsii as well as biological factors such as predation and recruitment rates. It is also worth noting that the phenotypic shell variability observed for this protobranch species in geographically close sites (hundreds of meters) highlights the importance of local-scale heterogeneity to be considered in future monitoring programmes for Antarctic marine ecosystems. [ABSTRACT FROM AUTHOR]

Thyrinteina arnobia (Lepidoptera: Geometridae) is a native American species. Despite its historical importance as an insect pest in Eucalyptus plantations, more information is needed regarding the population diversity, demography, and climatic variables associated with its distribution in different regions of Brazil. We used a phylogeographic approach to infer the genetic diversity, genetic structure, and demographic parameters of T. arnobia. We also conducted an ecological niche modeling (ENM) to predict suitable areas for T. arnobia occurrence in Brazil and other countries worldwide. Although T. arnobia populations have low genetic diversity in Brazil, we identified mitochondrial haplogroups predominating in different Brazilian regions and high ФST and ФCT values in AMOVA, suggesting a low frequency of insect movement among these regions. These results indicate that outbreaks of T. arnobia in Eucalyptus areas in different regions of Brazil are associated with local or regional populations, with no significant contribution from long-distance dispersal from different regions or biomes, suggesting that pest management strategies would be implemented on a regional scale. In Brazil, the demographic and spatial expansion signals of T. arnobia seem to be associated with the history of geographical expansion of Eucalyptus plantations, a new sustainable host for this species. ENM indicated that isothermality and annual rainfall are critical climatic factors for the occurrence of T. arnobia in tropical and subtropical areas in the Americas. ENM also suggested that T. arnobia is a potential pest in Eucalyptus areas in all Brazilian territory and in regions from Africa, Asia, and Oceania. [ABSTRACT FROM AUTHOR]

Elaeocarpus venustus is a steno‐endemic and Critically Endangered tree species of the Agasthyamalai Biosphere Reserve, southern Western Ghats, India. Due to its restricted distribution and specific habitat, a detailed field survey of existing populations was carried out. In order to clarify the taxonomic circumscription of this species in view of earlier literature, a revised taxonomic description is presented—together with details of the populations and ecology of this little‐known species and photographic documentation. [ABSTRACT FROM AUTHOR]

Turtle ecology and conservation have been poorly explored in the West African Sahel regions, and this scarce information has produced a suboptimal management of their populations in the wild. In order to enhance the knowledge on the Sahelian turtle ecology, a field study was carried out in Burkina Faso on the ecology of Pelomedusa subrufa olivacea, a freshwater species inhabiting a wide range of waterbodies throughout West Africa. Reasoned sampling was carried out, resulting in the collection of a total of 196 individuals of Pelomedusa subrufa olivacea. This species shows a relatively balanced distribution of age and sex classes of individuals surveyed in the different study areas. The majority of individuals were observed in specific habitats, confirmed by an aggregative distribution. The potential habitats identified by the MaxEnt model highlight key areas for the conservation of this species in Burkina Faso. Conservation efforts should focus on protecting and restoring temporary and permanent aquatic habitats, and managing human activities to minimize the impact on turtle populations in the West African Sahel. [ABSTRACT FROM AUTHOR]

Simple Summary: It is common knowledge that Snowy Owls eat lemmings during the nesting season, and it is believed that lemming populations fluctuate dramatically over several years, often termed a cycle. When lemming populations reach high densities, Snowy Owls have a highly successful breeding season, producing numerous young per nest. This successful nesting results in large numbers of young Snowy Owls migrating south during their first winter. This movement, generally called an irruption migration, has been known for over a century, and stirs the admiration of the public. Indeed, each time an irruption migration happens, it is among the most popular wildlife viewing events in North America. Given this predator–prey relationship between Snowy Owls and lemmings, we were interested in quantifying how important lemmings were to Snowy Owls throughout their worldwide breeding range. Of the 15 studies we reviewed, 59,923 prey items were recorded. Lemmings were clearly the most important food source for breeding Snowy Owls, but voles were sometimes also important. Given the near obligate dependency on lemmings for breeding, one wonders how a changing climate will affect lemming populations and distribution, and consequently Snowy Owl breeding. And, will this affect the Snowy Owl breeding population, resulting in fewer young Snowy Owls migrating south during an irruption migration. We compared Snowy Owl feeding ecology from 15 breeding season studies throughout Nearctic and Palearctic circumpolar regions. We used raw data and information theory to assess the owls' feeding niche. Combined studies yielded 59,923 prey items, of which 59,585 were used for calculations. Overall, mean food niche breadth (FNB) was narrow: H′ = 1.95; R = 1.60, D = 0.526. In 10 of 15 studies, lemmings were > 71.8% of the owls' diet. In four studies, Lemmus was > 90% of the diet, and in three studies Dicrostonyx was >90% of the diet. In three other studies, Lemmus represented 71.8%, 73.8%, and 84.0% of the diet. In one study, Lemmus and Dicrostonyx were about equal: 49.1% and 47.5%. In the four remaining studies, Microtus and Clethrionomys voles were important. In contrast, of 5888 winter prey items from seven North American studies, the mean FNB (H′ = 4.61) was twice that of 15 breeding season scores, FNB (H' = 1.95). The Snowy Owl is primarily an obligate lemming predator for breeding. Changes to population ecology and distribution of lemmings due to climate change will have direct affects and effects on the Snowy Owls' reproductive output. The conservation of Snowy Owls is the conservation of lemmings. [ABSTRACT FROM AUTHOR]

The walleye pollock, Gadus chalcogrammus (Pallas, 1814), is one of the most commercially and ecologically valuable species in the Northwestern Pacific. However, combined pressures of overfishing and environmental changes have led to a substantial decline in its production in Japan and Russia since the 1990s, and a collapse in Korea since the 2000s. The objective of this study was to comprehensively examine its genetic diversity and population structure with an extensive sampling effort of 16 populations across the Northwestern Pacific including South Korea, Japan, and Russia. A multiplex PCR assay composed of seven microsatellite markers revealed a moderate level of observed heterozygosity (Ho = 0.369–0.599), which is lower than that reported in previous studies of this species. All loci were highly polymorphic, with the mean PIC ranging from 0.608 to 0.793. The structure of the 16 populations was characterized by heterozygote deficiency, a modest effective allele number (Ne = 4.551–7.969), low genetic differentiation (FST = 0.000–0.054), a weak population structure, a genetic admixture, and no significant correlation between the genetic and geographic distance. These characteristics are typical of pelagic marine species with large population sizes due to a consistent gene flow among populations when there are no physical boundaries in the open ocean. The seasonal and country-specific genetic structure indicated that G. chalcogrammus populations in the Northwestern Pacific region should be managed as a single management unit. The findings from this study provide critical information for future genetic monitoring, conservation management, and the development of strategies aimed at restoring the populations of this species. [ABSTRACT FROM AUTHOR]

Knowledge about sex‐specific difference in life‐history traits—like growth, mortality, or behavior—is of key importance for management and conservation as these parameters are essential for predictive modeling of population sustainability. We applied a newly developed molecular sex identification method, in combination with a SNP (single nucleotide polymorphism) panel for inferring the population of origin, for more than 300 large Atlantic bluefin tuna (ABFT) collected over several years from newly reclaimed feeding grounds in the Northeast Atlantic. The vast majority (95%) of individuals were genetically assigned to the eastern Atlantic population, which migrates between spawning grounds in the Mediterranean and feeding grounds in the Northeast Atlantic. We found a consistent pattern of a male bias among the eastern Atlantic individuals, with a 4‐year mean of 63% males (59%–65%). Males were most prominent within the smallest (< 230 cm) and largest (> 250 cm) length classes, while the sex ratio was close to 1:1 for intermediate sizes (230–250 cm). The results from this new, widely applicable, and noninvasive approach suggests differential occupancy or migration timing of ABFT males and females, which cannot be explained alone by sex‐specific differences in growth. Our findings are corroborated by previous traditional studies of sex ratios in dead ABFT from the Atlantic, the Mediterranean, and the Gulf of Mexico. In concert with observed differences in growth and mortality rates between the sexes, these findings should be recognized in order to sustainably manage the resource, maintain productivity, and conserve diversity within the species. [ABSTRACT FROM AUTHOR]

Estimating correlations among demographic parameters is an important method in population ecology. A recent paper by Deane et al. (Ecology and Evolution 13:e9847, 2023) attempted to explore the effects of different priors for covariance matrices on inference when using mark‐recovery data. Unfortunately, Deane et al. (2023) made a mistake when parameterizing some of their models. Rather than exploring the effects of different priors, they examined the effects of the use of incorrect equations on inference. In this manuscript, we clearly describe the mistake in Deane et al. (2023). We then demonstrate the use of an alternative and appropriate method and reach different conclusions regarding the effects of priors on inference. Consistent with other recent literature, informative inverse Wishart priors can lead to flawed inference, while vague priors on covariance matrix components have little impact when sample sizes are adequate. [ABSTRACT FROM AUTHOR]

Long‐term ecological data are of paramount importance to document the effects of global changes on biodiversity and dynamics of populations and communities. The site of Bandia, 70 km southeast of Dakar in western Senegal, has been the scene of numerous ecological studies since the 1970s. In the frame of projects led by researchers of the Institut de Recherche pour le Développement (IRD), rodent populations were monitored at various periods using capture‐mark‐recapture (CMR) protocols on trapping grids that yielded important datasets on population dynamics and ecology of the main species present. Among them, the Guinea Multimammate Rat Mastomys erythroleucus proved to represent the dominant species. Thus, CMR data were collected on M. erythroleucus between (i) November 1975–March 1981, (ii) January 1983–October 1986, (iii) January 1997–April 2001, and (iv) June 2007–June 2012. Raw data from the 1975–1981 period were not available, but those from the three other periods are now in the IRD data repository DataSuds at https://doi.org/10.23708/YEA5AR. They represent 2556 (re)captures of 1296 M. erythroleucus individuals. They include the identity of each animal captured with some biological attributes (sex, weight at first capture, and reproductive activity), exact date and point of capture (via a trap‐specific code) at each trapping occasion, and additional comments that may help to interpret the data. This dataset concerning one of the most widespread rodent species of the Sahelo‐Sudanian bioclimatic belt provides information that can be used to address various questions such as outbreak prediction or effects of climate change. The complete data set for this abstract published in the Data Article section of the journal is also available in electronic format in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP-2024-05.1/jalter-en. [ABSTRACT FROM AUTHOR]

Demographic processes that ensure the recovery and resilience of marine populations are critical as climate change sends an increasing proportion on a trajectory of decline. Yet for some populations, recovery potential remains high. We conducted annual monitoring over 9 years (2012–2020) to assess the recovery of coral populations belonging to the genus Pocillopora. These populations experienced a catastrophic collapse following a severe typhoon in 2009. From the start of the monitoring period, high initial recruitment led to the establishment of a juvenile population that rapidly transitioned to sexually mature adults, which dominated the population within 6 years after the disturbance. As a result, coral cover increased from 1.1% to 20.2% during this time. To identify key demographic drivers of recovery and population growth rates (λ), we applied kernel‐resampled integral projection models (IPMs), constructing eight successive models to examine annual change. IPMs were able to capture reproductive traits as key demographic drivers over the initial 3 years, while individual growth was a continuous key demographic driver throughout the entire monitoring period. IPMs further detected a pulse of reproductive output subsequent to two further Category 5 typhoon events during the monitoring period, exemplifying key mechanisms of resilience for coral populations impacted by disturbance. Despite rapid recovery, (i.e., increased coral cover, individual colony growth, low mortality), IPMs estimated predominantly negative values of λ, indicating a declining population. Indeed, while λ translates to a change in the number of individuals, the recovery of coral populations can also be driven by an increase in the size of surviving colonies. Our results illustrate that accumulating long‐term data on historical dynamics and applying IPMs to extract demographic drivers are crucial for future predictions that are based on comprehensive and robust understandings of ecological change. [ABSTRACT FROM AUTHOR]

The complete study of semiaquatic ectothermic animals is often limited by the researchers' ability to detect them in their nonbreeding habitat. This is particularly challenging for semiaquatic amphibians whose detectability is greatest during the breeding season as they engage in visual and or auditory reproductive behaviors within specific aquatic microhabitats. Our collective ability to obtain information on the nonbreeding terrestrial habitat use and occupancy of postmetamorphic hylid treefrogs is markedly difficult because they are typically highly cryptic and vertically mobile, and it is often unfeasible to outfit smaller individuals with radiotelemetry devices. Because amphibians represent one of the most at-risk group of vertebrates, there is a great urgency to better understand both the breeding and nonbreeding natural history parameters of postmetamorphic individuals to inform species-specific and ecosystem-level management and conservation strategies. Therefore, in this study, we attempted the nearly year-round detection and capture of postmetamorphic treefrogs and their distinct age–sex groups in a previously unstudied remnant swamp wetland complex in southern Illinois, USA. We used 70 artificial refugia made of polyvinyl chloride (PVC) pipes mounted to trees within the upland aquatic-terrestrial ecotone of a single pond site to examine the factors influencing their nonbreeding occupancy and detection. Our artificial refugia allowed us to detect and capture the various age–sex groups of three Hyla species over an 8-mo period from April to November 2022. Using single-season Bayesian occupancy models, we found that the overall probability of occupancy among Cope's Gray Treefrogs (Hyla chrysoscelis) was primarily influenced by the relative ratio of an occupied refugia being consecutively occupied (i.e., the probability of a refugium being occupied was influenced by its previous occupancy state) and the probability of their detection was most influenced by the survey temperature. Importantly, we found nontrivial variation in the influence of both site-and-survey–specific occupancy and detection covariates among the different H. chrysoscelis age–sex groups, indicating at least partial differentiation in nonbreeding refuge preferences and requirements. Overall, our findings validate the use of tree-mounted artificial PVC refugia to detect and gather otherwise unattainable, nearly year-round, population-level information on the various age–sex groups of terrestrial, postmetamorphic, nonbreeding treefrogs in a remnant southern Illinois swamp wetland complex. [ABSTRACT FROM AUTHOR]

Understanding the effect of environmental factors on population characteristics of amphibians is crucial for their conservation and management. This is especially pertinent in regions vulnerable to climate change, such as the Qinghai–Tibetan Plateau (QTP). Here, we investigated the underlying environmental factors affecting the occurrence and abundance of Tibetan frogs (Nanorana pleskei) in the Three-River-Source region (TRSR) on the QTP. We found that N. pleskei is predominantly located in the headwater region of the Lancang River, with an increasing population size from northwest to southeast across the TRSR. Temperature oscillation acts as an ecological filter to determine the occurrence pattern, whereas the abundance is jointly influenced by maximum monthly temperature and precipitation and precipitation variability. Our study presents up-to-date information on the distribution and population status of N. pleskei in the hinterland of the QTP, which can assist conservation practitioners in developing effective management plans. Furthermore, our findings can contribute to the understanding of the distribution and abundance of amphibians within challenging high-elevation and plateau environments, offering insights that are valuable for the conservation and management of other amphibian species inhabiting similar high-elevation regions. [ABSTRACT FROM AUTHOR]

Long-term effects of current climate on animal populations living in subterranean habitats are still poorly understood. In this study, we analyzed the variability of the demographic structure and abundance of a population of terrestrial plethodontid Strinati's Cave Salamanders (Speleomantes strinatii) (Aellen, 1958) living inside a northwestern Italian artificial cave over 27 yr from 1996 to 2022. The study site is situated in the Northern Apennines, where average air temperatures measured at two local weather stations were steadily increasing, whereas precipitation was relatively constant over the past 60 yr. Our objective was to evaluate whether the demographic traits of the population of Strinati's Cave Salamanders were showing detectable signs of directional shift during the 27 yr. Each year in July, the population abundance was estimated by a three-occasion removal experiment, salamanders' snout–vent length (SVL) was measured, and the population polymodal body-size distribution was decomposed into estimated age classes. The annual population abundance, adult sex ratio, recruitment, SVL, and growth increments of first- and second-year immature salamanders were analyzed. The Strinati's Cave Salamander time series was modeled by autoregressive moving average (ARMA) analysis, and demographic parameters were tested for temporal trends. There were no directional trends observed in any of the demographic parameters of the focal cave salamander population over the study period. The best autoregressive model describing the population variation was an ARMA (2,1). Results indicated that the salamander population had a complex fluctuating pattern in which the interaction of lagged density dependence and an external autocorrelated factor were influencing the population long-term dynamics. Our findings suggest that the population of this long-lived salamander species was probably buffered from external conditions by the thermal inertia of its subterranean habitat that is known to delay and reduce the amplitude of aboveground climatic signals. [ABSTRACT FROM AUTHOR]

Despite years of debate, the factors that control the long-term carrying capacity of human populations are not well understood. In this paper, we assess the effect of changes in resource extraction and climate-driven changes in ecosystem productivity on the carrying capacity of hunter-gatherer populations in a terrestrial and coastal ecosystem. To make this assessment, we build time-series estimates of changes in resource extraction using stable isotopes and ecosystem productivity using paleoclimate models and geomorphic records of flood events. These estimates of resource extraction and ecosystem productivity allow us to assess a complex model of population expansion that proposes linked changes between population density, resource extraction, and intensification. We find that changes in resource extraction had a larger effect on carrying capacity in both the terrestrial and coastal ecosystems than climate drivers of ecosystem productivity. Our results are consistent with the idea that both Malthusian limits on resources and Boserupian pressures to reorganize economic systems operate in hunter-gatherer populations over the long term. Our data and analysis contribute to evaluating complex models of population growth and subsistence change across archaeological cases. [ABSTRACT FROM AUTHOR]

Learning is central to our understanding of how behaviour is shaped by the environment. A key open question is whether learning across contexts evolves as an integrated process, or whether learning in each context is free to evolve separately. Here, we measured learning in two sensory contexts in multiple genotypes and both sexes of two closely related, but ecologically divergent, species of fruit flies, Drosophila simulans and Drosophila sechellia. These species are morphologically very similar but differ dramatically in ecology and population biology. We tested how flies from each genotype, sex and species responded to and learned about different gustatory and visual cues. This approach allowed us to test whether species differences in learning were independent or correlated across contexts. Surprisingly, we found no evidence that D. simulans learned in any of our treatments. In contrast, D. sechellia learned to avoid gustatory stimuli that were paired with an aversive stimulus, as predicted, but unexpectedly learned to approach visual stimuli that were paired with the aversive stimulus. At the genotype level, genotypes, but not species, differed in their naïve responses to stimuli, but genotypes did not differ in learning in either species. Our results demonstrate that D. sechellia indeed differs from D. simulans in both learning contexts, but in a stimulus-dependent way. We suggest that studies of additional species or population pairs that employ this framework will be critical for evaluating the dimensionality of learning and its evolution. • We compared gustatory and visual learning in genotypes of two Drosophila species. • Only D. sechellia (not D. simulans) learned to avoid gustatory + aversive stimuli. • Unexpectedly, D. sechellia also learned to approach visual + aversive stimuli. • Genotypes differed in naïve responses to stimuli but not in learning in either species. • The two species differed in both learning contexts in a stimulus-dependent way. [ABSTRACT FROM AUTHOR]

Knowledge innovation is the driving force and guarantee of regional development. Inspired by population ecology, this article uses symbiosis theory to explore the symbiotic relationship of subjects in the regional knowledge innovation ecosystem. The nonlinear Lotka–Volterra model is constructed with the main subjects to measure the knowledge innovation ability of knowledge innovation subjects. The symbiotic relationships among the knowledge innovation subjects in each region are identified. Taking Beijing, Shanghai, and Guangzhou as examples, a sensitivity analysis of the initial value and coopetition relationship is conducted. The results show that the initial value change has no significant effect on the development of knowledge innovation subjects. The interaction relationships among subjects directly affect the symbiotic evolution trend. The study extends the application scope of the symbiosis theory and develops a theoretical framework for the development of subjects in regional knowledge innovation ecosystem. It offers regions a reference to use Lotka–Volterra model adjusting the knowledge innovation structure in various regions. [ABSTRACT FROM AUTHOR]

Yellow sticky traps (YSTs) are common tools for monitoring the greenhouse whitefly (GWF), Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae), which can cause significant yield reduction in different greenhouse crops such as cucumber and tomato. In recent years, sticky traps equipped with green light-emitting diodes (LEDs) have also been (successfully) tested for catching GWFs. However, no study has observed GWF population dynamics at low population densities using such LED traps for early pest detection in crop stands. Therefore, a greenhouse experiment was conducted aiming to investigate the correlation between GWF populations on tomato crops (Solanum lycopersicum L. (Solanaceae)) and the numbers caught on yellow sticky traps and green LED traps, respectively. A small number of whiteflies was released into two pest-free greenhouse cabins, and populations on plants and traps were monitored for the duration of two months. The results show that the GWFs caught on LED traps correlate significantly positive with the population density on the tomato crops. Such a correlation was not found for standard YSTs. Moreover, the results indicate the possibility of early pest detection using LED traps. The findings are discussed in the context of the whiteflies' ecology and population dynamics in greenhouses. [ABSTRACT FROM AUTHOR]

In recent years, motivated by widespread declines in wild bees, ecologists have prioritized learning about patterns of wild bee communities across the landscape at the expense of learning about the population‐level mechanisms driving those patterns. In this essay, we seek to revitalize the tradition of studying wild bee populations in a way that both contributes key knowledge for bee conservation and builds a strong conceptual understanding of the processes underpinning bee populations. We address two widespread concerns about investing in population‐level research. First, that population‐level studies are too conceptually narrow to provide broad inference. If population‐level studies are couched in general ecological theory, then findings from a single species can be generalized to many. We highlight how wild bees would make excellent candidates for exploring five areas of general ideas in population ecology, including nutritional ecology, drivers of vital rates, phenology and voltinism, habitat selection, and movement. Second, we address the concern that methods for studying bees at the population level are too difficult to implement. Methods for conducting population‐level studies of bees—specifically, identifying living bees in the field and studying individuals throughout their life cycles—are feasible to implement at the scales appropriate for answering population‐level questions, for example, a few species at a few sites. To facilitate adoption of these ideas, we developed an online field guide (www.watchingbees.com) and a detailed methods manual. More generally, we emphasize the value of linking data‐rich pattern‐oriented approaches in ecology with an understanding of the basic biology and mechanisms that generate those patterns. [ABSTRACT FROM AUTHOR]

Abstract Thyrinteina arnobia (Lepidoptera: Geometridae) is a native American species. Despite its historical importance as an insect pest in Eucalyptus plantations, more information is needed regarding the population diversity, demography, and climatic variables associated with its distribution in different regions of Brazil. We used a phylogeographic approach to infer the genetic diversity, genetic structure, and demographic parameters of T. arnobia. We also conducted an ecological niche modeling (ENM) to predict suitable areas for T. arnobia occurrence in Brazil and other countries worldwide. Although T. arnobia populations have low genetic diversity in Brazil, we identified mitochondrial haplogroups predominating in different Brazilian regions and high ФST and ФCT values in AMOVA, suggesting a low frequency of insect movement among these regions. These results indicate that outbreaks of T. arnobia in Eucalyptus areas in different regions of Brazil are associated with local or regional populations, with no significant contribution from long-distance dispersal from different regions or biomes, suggesting that pest management strategies would be implemented on a regional scale. In Brazil, the demographic and spatial expansion signals of T. arnobia seem to be associated with the history of geographical expansion of Eucalyptus plantations, a new sustainable host for this species. ENM indicated that isothermality and annual rainfall are critical climatic factors for the occurrence of T. arnobia in tropical and subtropical areas in the Americas. ENM also suggested that T. arnobia is a potential pest in Eucalyptus areas in all Brazilian territory and in regions from Africa, Asia, and Oceania.

Plant strategies are phenotypes shaped by natural selection that enable populations to persist in a given environment. Plant strategy theory is essential for understanding the assembly of plant communities, predicting plant responses to climate change, and enhancing the restoration of our degrading biosphere. However, models of plant strategies vary widely and have tended to emphasize either functional traits or life‐history traits at the expense of integrating both into a general framework to improve our ecological and evolutionary understanding of plant form and function. Advancing our understanding of plant strategies will require investment in two complementary research agendas that together will unify functional ecology and population ecology. First, we must determine what is phenotypically possible by quantifying the dimensionality of plant traits. This step requires dense taxonomic sampling of traits on species representing the broad diversity of phylogenetic clades, environmental gradients, and geographical regions found across Earth. It is important that we continue to sample traits locally and share data globally to fill biased gaps in trait databases. Second, we must test the power of traits for explaining species distributions, demographic rates, and population growth rates across gradients of resource limitation, disturbance regimes, temperature, vegetation density, and frequencies of other strategies. This step requires thoughtful, theory‐driven empiricism. Reciprocal transplant experiments beyond the native range and synthetic demographic modelling are the most powerful methods to determine how trait‐by‐environment interactions influence fitness. Moving beyond easy‐to‐measure traits and evaluating the traits that are under the strongest ecological selection within different environmental contexts will improve our understanding of plant adaptations. Plant strategy theory is poised to (i) unpack the multiple dimensions of productivity and disturbance gradients and differentiate adaptations to climate and resource limitation from adaptations to disturbance, (ii) distinguish between the fundamental and realized niches of phenotypes, and (iii) articulate the distinctions and relationships between functional traits and life‐history traits. [ABSTRACT FROM AUTHOR]

The significant loss of semi-natural grasslands in Japan has led to a decline in the populations of grassland specialist insects. We studied the population structure and basic ecology of a grassland specialist, the red-winged grasshopper Celes skalozubovi akitanus, a critically endangered species in Japan, to enable conservation management of grasshoppers and their habitats. A field survey using transect counts and a mark–release–recapture survey was conducted over two years (2016 and 2017). We found that C. s. akitanus fed on a variety of grassland plants in the study area but not on the dominant species Miscanthus sinensis and Pteridium aquilinum. The recapture rate of C. s. akitanus was considerably high (approximately 68% or more), and two isolated populations were found in the studied grassland. The estimated total population size was < 120–140 individuals, indicating that the study population was extremely small. Our results show that this species exhibits a strong sedentary behaviour because most of the adults move less than 5 m in a season and prefer bare ground within the grassland. The continued implementation of the annual prescribed burning and partial mowing of the habitat is necessary to conserve C. s. akitanus. In addition, creating continuity between two populations is effective for the survival of populations in this study area. [ABSTRACT FROM AUTHOR]

Measuring infaunal population dynamics relies on destructive sampling that disturbs sediments and removes animals from their habitat. Establishing effective, non-invasive sampling methods for monitoring infaunal populations can reduce the impact of scientific sampling and facilitate efficient population assessments. Using intertidal soft-shell clams (Mya arenaria L.) in eastern Canada, we explored whether population density and size structure could be estimated from visible siphon holes. Across four sites with varying sediment characteristics and infaunal species assemblages, we predicted the presence of M. arenaria with 78–100% accuracy by visually assessing siphon holes. Smaller holes (< 7.5 mm) were more likely to be misidentified. Siphon hole count was a strong predictor of actual clam count and biomass at most sites, except the site with wet muddy sediment and high densities of other infaunal species. Siphon hole length was positively related to clam shell length and wet weight at all sites; however, relationships typically had low R2 values (< 0.35). Ultimately, visual assessments of intertidal siphon holes can be effective for estimating M. arenaria densities and size structure in some habitats. Testing the application of this method to other habitats and species is warranted. [ABSTRACT FROM AUTHOR]

Mate-choice copying is a type of social learning in which females can change their mate preference after observing the choice of others. This behaviour can potentially affect population evolution and ecology, namely through increased dispersal and reduced local adaptation. Here, we simulated the effects of mate-choice copying in populations expanding across an environmental gradient to understand whether it can accelerate or retard the expansion process. Two mate-choice copying strategies were used: (i) when females target a single individual and (ii) when females target similar individuals. We also simulated cases where the male trait singled out by females with mate choice maps perfectly onto his genotype or is influenced by genotype-by-environment interactions. These rules have different effects on the results. When a trait is determined by genotype alone, populations where copier females target all similar males expand faster and the number of potential copiers increased. However, when preference is determined by genotype-by-environment interactions, populations where copier females target a single male had higher dispersal and also expand faster, but the potential number of copiers decreases. The results show that mate-choice copying can accelerate the expansion process, although its adaptiveness depends on the information animals use in different contexts. [ABSTRACT FROM AUTHOR]

Simple Summary: The daily activity rhythms of herbivores have significant ecological and conservation implications. Most studies have focused on predators and their prey, as well as sympatric carnivores or herbivores, with little attention given to ungulates in predator-free ecosystems. Using camera traps, we systematically studied the activity patterns and grouping characteristics of goitered gazelles in the Helan Mountains. Our findings reveal that goitered gazelles are crepuscular-like, with activity peaks occurring after dawn and before dusk. Their daily activity patterns and grouping characteristics vary across seasons, likely influenced by climatic conditions and resource availability. This research provides essential ecological insights for the restoration and conservation of goitered gazelle populations and underscores the importance of further behavioral studies on ecologically significant rare species in isolated habitats. Wildlife activity patterns, which reveal the daily allocation of time and energy, are crucial for understanding survival pressures, adaptive strategies, and behavioral characteristics in different environments. Among ungulates, grouping behavior is a prevalent adaptive trait that reflects the population structure, mating systems, and life history strategies formed over long-term evolutionary processes. This study aimed to elucidate the daily activity patterns and grouping characteristics of the rare goitered gazelle (Gazella subgutturosa) in the Helan Mountains of western China from 2022 to 2023 using camera trap monitoring. With a total of 3869 camera days of effective trapping, we recorded 442 independent detections of goitered gazelles. The results revealed the following: (1) Goitered gazelle is primarily active during the day, showing an activity pattern similar to crepuscular animals, with two activity peaks occurring after dawn and before dusk. (2) Daily activity patterns showed both seasonal and sex differences. In the warm season, morning activity peaks occurred earlier, and afternoon peaks occurred later compared to the cold season. The overlap in daily activity patterns between females and males in the warm season was lower than that in the cold season, and this trend persisted throughout the year. (3) The number of times different types of groups were observed varied significantly, with single males and single females accounting for a larger proportion of all observed groups. There was no significant difference in group size across seasons, with groups typically consisting of 1–2 individuals. Our study provides detailed insights into the temporal ecology and population structure of goitered gazelles in arid and semi-arid ecosystems. This information will guide the identification of future conservation priorities and the development of management plans for the reserve. [ABSTRACT FROM AUTHOR]

Individual variability in mortality is widespread in nature. The general rule is that larger organisms have a greater chance of survival than smaller conspecifics. There is growing evidence that differential mortality between developmental stages has important consequences for the ecology and evolution of populations and communities. However, we know little about how it can influence diversification. Using an eco-evolutionary model of diversification that considers individual variability in mortality, I show that commonly observed differences in mortality between juveniles and adults can facilitate adaptive diversification. In particular, diversification is expected to be less restricted when mortality is more biased toward juveniles. Additionally, I find stage-specific differences in metabolic cost and foraging capacity to further facilitate diversification when adults are slightly superior competitors, due to either a lower metabolic cost or a higher foraging capacity, than juveniles. This is because by altering the population composition, differential stage-specific mortality and competitive ability can modulate the strength of intraspecific competition, which in turn determines the outcome of diversification. These results demonstrate the strong influence that ecological differences between developmental stages have on diversification and highlight the need for integrating developmental processes into diversification theory. [ABSTRACT FROM AUTHOR]

The population of common cuttlefish Sepia officinalis in the English Channel recently developed two life cycles: annual (spawning 1 y.o.) and biennial (spawning 2 y.o.) instead of the biennial strategy known before, associated with increasing environmental temperatures in recent decades because of climate changes. Both groups differ in the size of mature animals (110–196 mm mantle length vs. 140–262 mm) and the number of chambers in the cuttlebone (60–97 in annual vs. 93–152 in biennial). The annual group represented some 15%–20% of the population, and the proportion of early spawners increased during the reproductive period, from 3%–5% in February/March to 50%–70% in June/July. Among spawning cuttlefish males predominated as ~2:1. Such environmentally driven changes in historical ecology as exemplified by the cuttlefish might be a critical link in the adaptation of the cephalopod life cycles to changing ecosystems. [ABSTRACT FROM AUTHOR]

Understanding how populations respond to variability in environmental conditions and interspecific interactions is one of the biggest challenges of population ecology, particularly in the context of global change. Although many studies have investigated population responses to climate change, very few have explicitly integrated interspecific relationships when studying these responses. In this study, we aimed to understand the combined effects of interspecific interactions and environmental conditions on the demographic parameters of a prey–predator system of three sympatric seabird populations breeding in Antarctica: the south polar skua (Catharacta maccormicki) and its two main preys during the breeding season, the Adélie penguin (Pygoscelis adeliae) and the emperor penguin (Aptenodytes forsteri). We built a two‐species integrated population model (IPM) with 31 years of capture–recapture and count data and provided a framework that made it possible to estimate the demographic parameters and abundance of a predator–prey system in a context where capture–recapture data were not available for one species. Our results showed that predator–prey interactions and local environmental conditions differentially affected south polar skuas depending on their breeding state of the previous year. Concerning prey–predator relationships, the number of Adélie penguin breeding pairs showed a positive effect on south polar skua survival and breeding probability, and the number of emperor penguin dead chicks showed a positive effect on the breeding success of south polar skuas. In contrast, there was no evidence for an effect of the number of south polar skuas on the demography of Adélie penguins. We also found an important impact of sea ice conditions on both the dynamics of south polar skuas and Adélie penguins. Our results suggest that this prey–predator system is mostly driven by bottom‐up processes and local environmental conditions. [ABSTRACT FROM AUTHOR]

The hypothesis of chaotic population dynamics was proposed in ecology by Robert May in the mid-1970s. At that time the idea was controversial, and it remains a fascinating and unsettled issue today. We report the results of a 20-year laboratory research programme that continued in the tradition of the pioneering ecologist Thomas Park using the Tribolium flour beetle model. We present biological evidence of complex population dynamics – including bifurcations, chaos, saddle nodes, phase switching, resonance effects, and multiple attractors – by using a low-dimensional difference equation model for Tribolium together with carefully designed, conducted, and statistically analysed experiments. The model, parameterized with data, also explains the results of historical Tribolium experiments, such as the classical competition studies of Thomas Park and his colleagues. Our research programme has inspired other studies using the Tribolium mathematical and laboratory model. This work was conducted by a multidisciplinary team, which included Jim Cushing. [ABSTRACT FROM AUTHOR]

The Amazon boasts the highest anuran species diversity in the world. The Colombian Amazon has the highest rates of illegal deforestation, leading to accelerated species loss. The objective of this review was to identify knowledge shortfalls in anuran research to effectively address conservation efforts. We conducted a systematic literature search from different databases. To this end, we evaluated knowledge gaps in the published literature to pinpoint areas where information is lacking, aiming to address critical topics essential for advancing scientific understanding and informing effective conservation and management strategies. We read the Abstract, Methods, Study Area, Results and supplementary material for each document following the PRISMA (Preferred Reporting Items for Systematic reviews and Meta‐Analyses) protocol. We found 161 documents, with the earliest publications dating back to the 1940s, and the highest productivity occurring since 2000. The diversity of research topics has increased over time. The most studied topics were systematics and taxonomy, natural history, geographic distributions, while the least studied topics (with less than six documents) were cell biology and microbiology, genetics, toxicology, ethnobiology, diet, infectious diseases, biogeography and macroecology. There remains a need for further research in these underrepresented areas. Only 10 species were represented in more than 17 papers and 165 species were represented in less than three publications. Only three species (Allobates femoralis, Dendropsophus parviceps and Phyllomedusa bicolor) were studied from more than 10 topics and, in general, the studies concentrated on adult life stages, maintaining a gap in the knowledge of larval stages (Haeckelian shortfall). We found 296 anuran species reported in the published documents; and the departments of Amazonas, Caquetá and Putumayo had the highest number of studies with great knowledge gaps in Meta, Vichada, Nariño and Cauca. There was an important increase in the collection of primary field data, and the use of biological collections for specimen studies, with 30.6% and 40% of total studies in these periods, respectively, relying on these data sources. However, in the entire 76‐year span, there has been only one publication that conducted experiments on anurans, highlighting the considerable lack of eco‐physiological studies. Our review did not find a population ecology paper with detailed demographic data or life tables (Prestonian shortfall), although we did uncover six papers reporting abundance data of seven species that could be applied to conservation efforts. We found two papers that reported on functional traits such as reproductive modes and morphological traits (Raunkiæran shortfall); but we did not find a paper on biotic interactions (Eltonian shortfall), species'abiotic tolerances (Hutchinsonian shortfall), or explicit evolutionary patterns (Darwinian shortfall). Only five anuran species were listed in the "Catálogo de Anfibios y Reptiles de Colombia" and only two species have distribution models available on the BioModelos online platform to map Colombian species distribution (Wallacean shortfall). Of the 296 anuran species, 32 are classified under various IUCN threat categories, although these assessments were based solely on geographical distribution data (AOO and EOO) due to the lack of population trend information, resulting in 218 species categorized as of least conservation concern, due to their wide distribution. This study highlights the limited focus on anuran population ecology in the Colombian Amazon, despite its critical role in understanding demographic processes and species conservation. Herpetological research in the Amazon must focus on providing the following critical information for species conservation: (a) long‐term participatory population assessments in mature native forests, (b) detection of changes in the abundance and value of species' functional traits in response to landscape anthropogenic transformation and (c) the development and validation of species distribution maps for the Amazonian region. Sharing raw anuran species population and distribution data through open‐access platforms are crucial steps for the development of informed conservation strategies for the region. Such data enable early detection of habitat degradation and loss effects and establishes a research agenda for long‐term participatory monitoring of anuran species and their habitats. [ABSTRACT FROM AUTHOR]