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At least 91 records · Page 5Linked to original sources
USGS2007

Historic distribution and challenges to bison recovery in the northern Chihuahuan Desert

Ecologists and conservationists have long assumed that large grazers, including bison ( Bison bison ), did not occur in post-Pleistocene southwestern North America. This perception has been influential in framing the debate over conservation and land use in the northern Chihuahuan Desert. The lack of an evolutionary history of large grazers is being used to challenge the validity of ranching as a conservation strategy and to limit the protection and reintroduction of bison as a significant component of desert grassland ecosystems. Archeological records and historical accounts from Mexican archives from AD 700 to the 19th century document that the historic range of the bison included northern Mexico and adjoining areas in the United States. The Janos-Hidalgo bison herd, one of the few free-ranging bison herds in North America, has moved between Chihuahua, Mexico, and New Mexico, United States, since at least the 1920s. The persistence of this cross-border bison herd in Chihuahuan Desert grasslands and shrublands demonstrates that the species can persist in desert landscapes. Additional lines of evidence include the existence of grazing-adapted grasslands and the results of experimental studies that document declines in vegetation density and diversity following the removal of large grazers. The Janos-Hidalgo herd was formed with animals from various sources at the turn of the 19th century. Yet the future of the herd is compromised by differing perceptions of the ecological and evolutionary role of bison in the Desert Grasslands of North America. In Mexico they are considered native and are protected by federal law, whereas in New Mexico, they are considered non-native livestock and therefore lack conservation status or federal protection. Evidence written in Spanish of the presence of bison south of the accepted range and evidence from the disciplines of archaeology and history illustrate how differences in language and academic disciplines, in addition to international boundaries, have acted as barriers in shaping comprehensive approaches to conservation. Bison recovery in the region depends on binational cooperation.

Arizona, Chihuahua, Coahuila, Durango, New Mexico,↗
USGS2026

Understanding natal emigration in group-living carnivores

Dispersal is a critical ecological and evolutionary process, yet the drivers of individual variation in emigration, particularly under human-modified conditions, remain relatively understudied. We investigate the determinants and patterns of emigration in a managed population of cooperative breeders using genetic samples from harvested individuals. We used a novel genetic approach to identify natal emigration through sibship analyses of DNA from harvested grey wolves ( Canis lupus ), a cooperative-breeding species, and evaluated how prey biomass, wolf density, human-caused mortality and sex influenced natal emigration across Idaho, USA, from 2017 to 2023. From our analysis of 182 sibling groups (representing packs), we evaluated natal emigration status for 224 individuals. Of these, 86 were classified as emigrants and 138 as non-dispersers. We assessed how covariates influenced the probability of emigration and evaluated sex differences in apparent dispersal distance. We found no sex differences in emigration propensity or apparent dispersal distance. Emigrants dispersed an average of 81.8 km (range: 30.0–338.9 km) from their inferred natal territories. Emigration was more likely from territories with higher prey biomass and lower wolf density, while human-caused mortality had no detectable effect. We found that ecological drivers, such as prey availability and population density, have a stronger effect on the propensity to emigrate than harvest intensity. These results highlight the importance of resource availability and population dynamics in shaping dispersal patterns in a cooperative breeder. Our study used a novel genetic method to assess natal emigration in a group-living carnivore and developed a framework broadly applicable to social systems where kin structures can be traced to dispersers. Our findings identify landscape-scale conditions that influence dispersal and can inform the management of wild populations.

Idaho↗
USGS2015

Factors affecting individual foraging specialization and temporal diet stability across the range of a large “generalist” apex predator

Individual niche specialization (INS) is increasingly recognized as an important component of ecological and evolutionary dynamics. However, most studies that have investigated INS have focused on the effects of niche width and inter- and intraspecific competition on INS in small-bodied species for short time periods, with less attention paid to INS in large-bodied reptilian predators and the effects of available prey types on INS. We investigated the prevalence, causes, and consequences of INS in foraging behaviors across different populations of American alligators ( Alligator mississippiensis ), the dominant aquatic apex predator across the southeast US, using stomach contents and stable isotopes. Gut contents revealed that, over the short term, although alligator populations occupied wide ranges of the INS spectrum, general patterns were apparent. Alligator populations inhabiting lakes exhibited lower INS than coastal populations, likely driven by variation in habitat type and available prey types. Stable isotopes revealed that over longer time spans alligators exhibited remarkably consistent use of variable mixtures of carbon pools (e.g., marine and freshwater food webs). We conclude that INS in large-bodied reptilian predator populations is likely affected by variation in available prey types and habitat heterogeneity, and that INS should be incorporated into management strategies to efficiently meet intended goals. Also, ecological models, which typically do not consider behavioral variability, should include INS to increase model realism and applicability.

Oecologia↗
USGS2018

Integrating animal movement with habitat suitability for estimating dynamic migratory connectivity

Context High-resolution animal movement data are becoming increasingly available, yet having a multitude of empirical trajectories alone does not allow us to easily predict animal movement. To answer ecological and evolutionary questions at a population level, quantitative estimates of a species’ potential to link patches or populations are of importance. Objectives We introduce an approach that combines movement-informed simulated trajectories with an environment-informed estimate of the trajectories’ plausibility to derive connectivity. Using the example of bar-headed geese we estimated migratory connectivity at a landscape level throughout the annual cycle in their native range. Methods We used tracking data of bar-headed geese to develop a multi-state movement model and to estimate temporally explicit habitat suitability within the species’ range. We simulated migratory movements between range fragments, and calculated a measure we called route viability. The results are compared to expectations derived from published literature. Results Simulated migrations matched empirical trajectories in key characteristics such as stopover duration. The viability of the simulated trajectories was similar to that of the empirical trajectories. We found that, overall, the migratory connectivity was higher within the breeding than in wintering areas, corroborating previous findings for this species. Conclusions We show how empirical tracking data and environmental information can be fused for meaningful predictions of animal movements throughout the year and even outside the spatial range of the available data. Beyond predicting migratory connectivity, our framework will prove useful for modelling ecological processes facilitated by animal movement, such as seed dispersal or disease ecology.

Landscape Ecology↗
USGS2022

Hybridization decreases native cutthroat trout reproductive fitness

Examining natural selection in wild populations is challenging, but crucial to understanding many ecological and evolutionary processes. Additionally, in hybridizing populations, natural selection may be an important determinant of the eventual outcome of hybridization. We characterized several components of relative fitness in hybridizing populations of Yellowstone cutthroat trout and rainbow trout in an effort to better understand the prolonged persistence of both parental species despite predictions of extirpation. Thousands of genomic loci enabled precise quantification of hybrid status in adult and subsequent juvenile generations; a subset of those data also identified parent–offspring relationships. We used linear models and simulations to assess the effects of ancestry on reproductive output and mate choice decisions. We found a relatively low number of late-stage (F3+) hybrids and an excess of F2 juveniles relative to the adult generation in one location, which suggests the presence of hybrid breakdown decreasing the fitness of F2+ hybrids later in life. Assessments of reproductive output showed that Yellowstone cutthroat trout are more likely to successfully reproduce and produce slightly more offspring than their rainbow trout and hybrid counterparts. Mate choice appeared to be largely random, though we did find statistical support for slight female preference for males of similar ancestry. Together, these results show that native Yellowstone cutthroat trout are able to outperform rainbow trout in terms of reproduction and suggest that management action to exclude rainbow trout from spawning locations may bolster the now-rare Yellowstone cutthroat trout.

Molecular Ecology↗
USGS2024

Intrinsic and environmental drivers of pairwise cohesion in wild Canis social groups

Animals within social groups respond to costs and benefits of sociality by adjusting the proportion of time they spend in close proximity to other individuals in the group (cohesion). Variation in cohesion between individuals, in turn, shapes important group-level processes such as subgroup formation and fission–fusion dynamics. Although critical to animal sociality, a comprehensive understanding of the factors influencing cohesion remains a gap in our knowledge of cooperative behavior in animals. We tracked 574 individuals from six species within the genus Canis in 15 countries on four continents with GPS telemetry to estimate the time that pairs of individuals within social groups spent in close proximity and test hypotheses regarding drivers of cohesion. Pairs of social canids ( Canis spp.) varied widely in the proportion of time they spent together (5%–100%) during seasonal monitoring periods relative to both intrinsic characteristics and environmental conditions. The majority of our data came from three species of wolves (gray wolves, eastern wolves, and red wolves) and coyotes. For these species, cohesion within social groups was greatest between breeding pairs and varied seasonally as the nature of cooperative activities changed relative to annual life history patterns. Across species, wolves were more cohesive than coyotes. For wolves, pairs were less cohesive in larger groups, and when suitable, small prey was present reflecting the constraints of food resources and intragroup competition on social associations. Pair cohesion in wolves declined with increased anthropogenic modification of the landscape and greater climatic variability, underscoring challenges for conserving social top predators in a changing world. We show that pairwise cohesion in social groups varies strongly both within and across Canis species, as individuals respond to changing ecological context defined by resources, competition, and anthropogenic disturbance. Our work highlights that cohesion is a highly plastic component of animal sociality that holds significant promise for elucidating ecological and evolutionary mechanisms underlying cooperative behavior.

Ecology↗
USGS2019

Coast to coast: High genomic connectivity in North American scoters

Dispersal shapes demographic processes and therefore is fundamental to understanding biological, ecological, and evolutionary processes acting within populations. However, assessing population connectivity in scoters ( Melanitta sp.) is challenging as these species have large spatial distributions that span remote landscapes, have varying nesting distributions (disjunct vs. continuous), exhibit unknown levels of dispersal, and vary in the timing of the formation of pair bonds (winter vs. fall/spring migration) that may influence the distribution of genetic diversity. Here, we used double‐digest restriction‐associated DNA sequence (ddRAD) and microsatellite genotype data to assess population structure within the three North American species of scoter (black scoter, M. americana ; white‐winged scoter, M. deglandi ; surf scoter, M. perspicillata ), and between their European congeners (common scoter, M. nigra ; velvet scoter, M. fusca ). We uncovered no or weak genomic structure (ddRAD Φ ST < 0.019; microsatellite F ST < 0.004) within North America but high levels of structure among European congeners (ddRAD Φ ST > 0.155, microsatellite F ST > 0.086). The pattern of limited genomic structure within North America is shared with other sea duck species and is often attributed to male‐biased dispersal. Further, migratory tendencies (east vs. west) of female surf and white‐winged scoters in central Canada are known to vary across years, providing additional opportunities for intracontinental dispersal and a mechanism for the maintenance of genomic connectivity across North America. In contrast, the black scoter had relatively elevated levels of divergence between Alaska and Atlantic sites and a second genetic cluster found in Alaska at ddRAD loci was concordant with its disjunct breeding distribution suggestive of a dispersal barrier (behavioral or physical). Although scoter populations appear to be connected through a dispersal network, a small percentage (<4%) of ddRAD loci had elevated divergence which may be useful in linking areas (nesting, molting, staging, and wintering) throughout the annual cycle.

North America↗
USGS2003

Long-term fitness consequences of early conditions in the kittiwake

1. The long - term fitness consequences of conditions during development are receiving growing attention: they are at the interface between ecological and evolutionary processes. We addressed the influence of the length of the rearing period and 'rank' on fitness components in a long -lived seabird species with deferred breeding: the kittiwake (Rissa tridactyla). Rank, which depends on hatching order, was used as a surrogate for dominance status in the brood. Rank could be viewed as a random factor affecting individuals regardless of their possible 'intrinsic quality' at birth. The length of the rearing period was used as a surrogate for parental effort. It reflects the interaction between numerous factors such as environmental conditions , parental quality, reproductive decisions and effort, and also offspring decisions and intrinsic quality at birth. 2. There was evidence of an influence of the length of the rearing period on local survival before recruitment. Individuals with shorter rearing periods had lower local survival during the first winter (e.g. the relationship was positive). They may incur higher mortality. In rank 1 prebreeders, this relationship was negative in older age-classes. Longer rearing periods and better condition at independence may be associated with stronger migrating ability, and prebreeders that have not yet made settlement decisions may emigrate permanently to distant locations. Such a complex pattern may reflect age-related changes in the relative contribution of mortality and permanent emigration to local survival. 3. The length of the rearing period had long - term consequences on reproductive performance. The relationship was positive but the rate of increase decreased slightly at higher values of the covariate. 4. There was an unambiguously negative influence of rank on survival before recruitment and recruitment probability, but not on demographic parameters specific to the reproductive stage. Juniors recruited later than elder siblings. The disadvantage of juniors may be expressed mainly in terms of higher mortality and disappearance from the population before recruitment.

Journal of Animal Ecology↗
USGS1991

Estimates of movement and site fidelity using mark-resight data of wintering Canada geese

Population ecologists have devoted disproportionate attention to the estimation and study of birth and death rates and far less effort to rates of movement. Movement and fidelity to wintering areas have important ecological and evolutionary implications for avian populations. Previous inferences about movement among and fidelity to wintering areas have been restricted by limitations of data and methodology. We use multiple observation data from a large-scale capture-resighting study of Canada Geese in the Atlantic flyway to estimate probabilities of returning to previous wintering locations and moving to new locations. Mark-resight data from 28,849 Canada Geese (Branta canadensis) banded woth individually coded neck bands in the mid-Atlantic (New York, Pennsylvania, New Jersey), Chesapeake (Delaware, Maryland, Virginia), and Carolinas (North and South Carolina) were used to estimate movement and site-fidelity. Two three-sample mark-resight models were developed and programmed using SURVIV to estimate the probability of moving among or remaining within these three wintering regions. The model (MV2) that incorporated tradition' or memory of previous wintering regions fit the data better than the model (MV1) that assumes that a first-order Markov chain described movement among regions. Considerable levels of movement occurred among regions of the Atlantic flyway. The annual probability of remaining in the same region for two successive winters, used as a measure of site fidelity, was 0.710 plus or minus 0.016 (estimated mean plus or minus SE, 0.889 plus or minus 0.006, and 0.562 plus or minus 0.025, for the mid-Atlantic, Chesapeake, and Carolinas, respectively. The estimated probability of moving between years corresponded to changes in winter harshness. In warm years, geese moved north and in cold years, they moved south. Geese had a high probability of moving to and remaining in the Chesapeake. Annual changes in the movement probabilities did not correspond to annual changes in the United States Fish and Wildlife midwinter survey. Considerable numbers of geese from the Carolinas appeared to be wintering in more northerly locations (short-stopped) in subsequent winters.

Ecology↗
USGS2021

Informed breeding dispersal following stochastic changes to patch quality in a pond-breeding amphibian

The unidirectional movement of animals between breeding patches (i.e. breeding dispersal) has profound implications for the ecological and evolutionary dynamics of spatially structured populations. In spatiotemporally variable environments, individuals are expected to adjust their dispersal decisions according to information gathered on the environmental and/or social cues that reflect the fitness prospects in a given breeding patch (i.e. informed dispersal). A paucity of empirical work limited our understanding of the ability of animals to depart from low-quality breeding patches and settle in high-quality breeding patches. We examined the capacity of individuals to respond to stochastic changes in habitat quality via informed breeding dispersal in a pond-breeding amphibian. We conducted a 5-year (2015–2019) capture–recapture study of boreal toads Anaxyrus boreas boreas ( n = 1,100) that breed in beaver ponds in western Wyoming, USA. During early spring of 2017, an extreme flooding event destroyed several beaver dams and resulted in the loss of breeding habitat. We used multi-state models to investigate how temporal changes in pond characteristics influenced breeding dispersal, and determine whether movement decisions were in accordance with prospects for reproductive fitness. Boreal toads more often departed from low-quality breeding ponds (without successful metamorphosis) and settled in high-quality breeding ponds (with successful metamorphosis). Movement decisions were context-dependent and associated with pond characteristics altered by beaver dam destruction. Individuals were more likely to depart from shallow ponds with high vegetation cover and settle in deep ponds with low vegetation cover. The probability of metamorphosis was related to the same environmental cues, suggesting that boreal toads assess the fitness prospects of a breeding patch and adjust movement decisions accordingly (i.e. informed breeding dispersal). We demonstrated that stochastic variability in environmental conditions and habitat quality can underpin dispersal behaviour in amphibians. Our study highlighted the mechanistic linkages between habitat change, movement behaviour and prospects for reproductive performance, which is critical for understanding how wild animals respond to rapid environmental change.

Wyoming↗
USGS2026

How wildlife respond to tropical cyclones: Short-term tactics and long-term impacts

From butterflies to lizards and from sharks to seabirds, wildlife exhibit tactics to survive the impacts of tropical cyclones, also known as hurricanes, cyclones, or typhoons depending on where they occur. Some species seek refuge during the storm by moving, some remain in place and ride it out, and others move longer distances, avoiding the main impacts of the storm altogether. Tropical cyclones can have direct impacts on wildlife (e.g. mortality) but can also have indirect effects by altering resources and habitat, with downstream impacts on abundance and recruitment. Using examples from across taxa and ecosystems, we explore the pathways by which tropical cyclones can influence wildlife populations and communities. We describe tactics demonstrated by wildlife that enable them to survive the immediate impacts of the storm, as well as the longer-term impacts after the storm. We give examples of tropical cyclones as a selective pressure and as a facilitator for the introduction of invasive species. We also describe how tropical cyclones may provide a net benefit to some native species. The ecological and evolutionary impacts of tropical cyclones on wildlife can be complex, as they are often intertwined with concurrent pressures from land-use change, human development, and climate change. As the frequency of intense tropical cyclones is predicted to increase globally, identifying the mechanisms by which wildlife cope with such disturbances can aid in understanding and mitigating the impacts of climate change on wildlife.

Biological Reviews↗
USGS2016

The extra mile: Ungulate migration distance alters the use of seasonal range and exposure to anthropogenic risk

Partial migration occurs across a variety of taxa and has important ecological and evolutionary consequences. Among ungulates, studies of partially migratory populations have allowed researchers to compare and contrast performance metrics of migrants versus residents and examine how environmental factors influence the relative abundance of each. Such studies tend to characterize animals discretely as either migratory or resident, but we suggest that variable migration distances within migratory herds are an important and overlooked form of population structure, with potential consequences for animal fitness. We examined whether the variation in individual migration distances (20–264 km) within a single wintering population of mule deer ( Odocoileus hemionus ) was associated with several critical behavioral attributes of migration, including timing of migration, time allocation to seasonal ranges, and exposure to anthropogenic mortality risks. Both the timing of migration and the amount of time animals allocated to seasonal ranges varied with migration distance. Animals migrating long distances (150–250 km) initiated spring migration more than three weeks before than those migrating moderate (50–150 km) or short distances (<50 km). Across an entire year, long-distance migrants spent approximately 100 more days migrating compared to moderate- and short-distance migrants. Relatedly, winter residency of long-distance migrants was 71 d fewer than for animals migrating shorter distances. Exposure to anthropogenic mortality factors, including highways and fences, was high for long-distance migrants, whereas vulnerability to harvest was high for short- and moderate-distance migrants. By reducing the amount of time that animals spend on winter range, long-distance migration may alleviate intraspecific competition for limited forage and effectively increase carrying capacity. Clear differences in winter residency, migration duration, and risk of anthropogenic mortality among short-, moderate-, and long-distance migrants suggest fitness trade-offs may exist among migratory segments of the population. Future studies of partial migration may benefit from expanding comparisons of residents and migrants, to consider how variable migration distances of migrants may influence the costs and benefits of migration.

Wyoming↗
USGS2021

A greener future for the Galapagos: Forecasting ecosystem productivity by finding climate analogs in time

Forecasting ecosystem response to climate change is critical for guiding policymaking but challenging due to: complicated relationships between microclimates and regional climates; species’ responses that are driven by extremes rather than averages; the multifaceted nature of species’ interactions; and the lack of historical analogs to future climates. Given these challenges, even model systems such as the Galapagos Islands, a world-famous biodiversity hotspot and World Heritage Site, lack clear forecasts for future environmental change. Here, we developed a novel nonparametric method for simulating the ecosystem futures based on observed vegetation productivity (NDVI) during analogous weather observed historically. Using satellite images taken from the past to piece together a simulated future, we projected that productivity of terrestrial vegetation of the Galapagos will increase over the next century by approximately one standard deviation archipelago-wide, with largest increases during the wet season (January to June) and in the arid zones. Such greening would impact a variety of ecological and evolutionary processes, species of conservation concern, and agricultural practices. Our straightforward approach can be applied to many other regions, particularly those with rapid ecosystem responses to stochastic inter-annual climatic fluctuations that provide appropriate climate analogs for forecasting.

Galápagos Islands↗
USGS2022

Disease and secondary sexual traits: Effects of pneumonia on horn size of bighorn sheep

Secondary sexual traits (e.g., horns and antlers) have ecological and evolutionary importance and are of management interest for game species. Yet, how these traits respond to emerging threats like infectious disease remains underexplored. Infectious pneumonia threatens bighorn sheep ( Ovis canadensis ) populations across North America and we hypothesized it may also reduce horn growth in male sheep. We assess the effect of pneumonia on horn size in male bighorn sheep using 12 herd datasets from across the western United States that had horn growth and disease data. Disease resulted in 12–35% reduction in increment (yearly) length and 3–13% reduction in total horn length in exposed individuals. The disease effect was prolonged when pathogens continued to circulate in sheep populations. Further, disease likely delays the age at which horns reach ¾-curl and prevents achievement of full-curl. This is further evidenced with 6 of the 12 herds experiencing an increase in average age at harvest following die-off events.

Colorado, Idaho, Montana, Utah, Washington, Wyomin↗
USGS1995

Top-level carnivores and ecosystem effects: Questions and approaches

Top-level carnivores comprise a diverse array of taxa and occur in most natural ecosystems. This chapter considers three main questions: What are the ecological and evolutionary effects of top-level carnivores, how general are they, and under what conditions do they occur? To answer these questions one first must determine whether a food web is under top-down control, and ultimately, the species, systems, and circumstances for which top-down control exists. For systems affected by top-down forces, the cascading effect of carnivory on autotrophs is expected to vary with the order of trophic complexity. Given this conceptual framework, three more specific questions are explored. First, how general are the direct and indirect effects of top-level carnivores? Second, what is the breadth of trophic influence from the direct impact of carnivory? Broadly ranging effects are expected for systems in which (1) top-level carnivores occupy odd-numbered trophic levels and (2) the food web is strongly linked. (3) what are the evolutionary consequences of trophic cascades on species lower in the food web? These questions can best be answered via manipulative or natural experiments in which the presence or absence of carnivores varies in space or time. Natural experiments are advocated as the only practical means of addressing these questions for many species and systems, in particular those in which the key players are large and highly mobile, or those in which the manipulation of predators has legal, political, or social ramifications.

Linking Species and Ecosystems↗
USGS1996

The Bumpus house sparrow data: A reanalysis using structural equation models

We analysed the data of H.C. Bumpus on the survival of house sparrows ( Passer domesticus ) using structural equation modelling techniques. Using data on seven morphological variables measured by Bumpus, we tested and confirmed a three-factor model that characterized physical attributes for general size, leg size and head size. Although males were physically larger than females, we found no difference between males and females in the physical attributes as measured by the three factors. Survival increased significantly with increasing general size and was unrelated to leg size and head size. Wing length, independent of its relationship to the general size factor, was also significantly related to survival. Higher survival was found among birds with short wings. Males had a higher survival compared to females. Their higher survival was mediated, to a lesser extent indirectly, through greater size and, to a greater extent directly, through effects of unknown origin. We favour the use of structural equation modelling methods in studies of selection because of their ability to test and confirm or disconfirm hypotheses related to selection events.

Evolutionary Ecology↗
USGS1992

Alternate reproductive strategies in the California gull

We analysed 6 years of reproduction data for 176 California gulls ( Larus californicus ) surviving from 1980 to 1988. Using a statistical model adapted from Rao's (1958) and Tucker's (1966) generalized growth curve analysis, we reconstructed the reproductive patterns of gulls aged from 0 to 26 years. Individuals were highly consistent in following one of two patterns of reproduction. In a primary pattern employed by most gulls, individuals skipped breeding less frequently and laid larger clutches as they aged. Clutch size increased to a plateau and remained at high levels throughout remaining life. In an alternate pattern employed by a smaller subset of the sample, clutch size also increased to a plateau. However, as a result of frequent skipping of breeding and smaller clutches, this plateau was considerably lower compared to that of gulls adopting the primary reproductive pattern. Data on fledging success from 1980 and 1984 were consistent with the finding of two reproductive patterns. Gulls adopting the alternate reproductive pattern produce fewer offspring per breeding attempt but survive longer than gulls adopting the primary pattern. The frequency of gulls employing the alternate pattern will increase with age relative to gulls employing the primary pattern. The alternate pattern, and not senescence, may explain why several cross-sectional studies on seabirds report declines among the oldest breeders in measures of clutch size, egg mass, hatching success, and fledging success.

Wyoming↗
USGS2015

Nest predation research: Recent findings and future perspectives

Nest predation is a key source of selection for birds that has attracted increasing attention from ornithologists. The inclusion of new concepts applicable to nest predation that stem from social information, eavesdropping or physiology has expanded our knowledge considerably. Recent methodological advancements now allow focus on all three players within nest predation interactions: adults, offspring and predators. Indeed, the study of nest predation now forms a vital part of avian research in several fields, including animal behaviour, population ecology, evolution and conservation biology. However, within nest predation research there are important aspects that require further development, such as the comparison between ecological and evolutionary antipredator responses, and the role of anthropogenic change. We hope this review of recent findings and the presentation of new research avenues will encourage researchers to study this important and interesting selective pressure, and ultimately will help us to better understand the biology of birds.

Journal of Ornithology↗