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The occurrence and distributions of wildlife populations and communities are shifting as a result of global changes. To evaluate whether these shifts are negatively impacting biodiversity processes, it is critical to monitor the status, trends, and effects of environmental variables on entire communities. However, modeling the dynamics of multiple species simultaneously can require large amounts of diverse data, and few modeling approaches exist to simultaneously provide species and community level inferences. We present an "integrated community occupancy model" (ICOM) that unites principles of data integration and hierarchical community modeling in a single framework to provide inferences on species-specific and community occurrence dynamics using multiple data sources. We use simulations to compare the ICOM to previously developed hierarchical community occupancy models and single species integrated distribution models. We then apply our model to assess the occurrence and biodiversity dynamics of foliage-gleaning birds in the White Mountain National Forest in the northeastern USA from 2010-2018 using three independent data sources. Simulations reveal that integrating multiple data sources in the ICOM increased precision and accuracy of species and community level inferences compared to single data source models, although benefits of integration were dependent on data source quality (e.g., amount of replication). Compared to single species models, the ICOM yielded more precise species-level estimates. Within our case study, the ICOM had the highest out-of-sample predictive performance compared to single species models and models that used only a subset of the three data sources. The ICOM offers an attractive approach to estimate species and biodiversity dynamics, which is additionally valuable to inform management objectives of both individual species and their broader communities., Comment: 30 pages, 4 figures

The Olive-sided Flycatcher (Contopus cooperi) is a steeply declining aerial insectivore with one of the longest migrations of any North American passerine. We deployed light-level geolocators and archival GPS tags on breeders in boreal Alaska to determine migratory routes, important stopovers and non-breeding locations. Data from 16 individuals revealed a median 23,555 km annual journey (range: 19,387, 27,292 km) over 95 days (range: 83, 139 days) with wintering occurring in three regions of South America (NW Colombia/Ecuador, central Peru and W Brazil/S Peru). We developed a new method to identify “Important Stopovers” by quantifying intensity of use (a function of bird numbers and stop durations) along migratory routes. We identified 13 Important Stopovers that accounted for ~66% of the annual migratory period, suggestive of refueling activities. Some sites coincided with key areas previously identified for other Neotropical-Nearctic migrants. Percent land “protected” at Important Stopovers, as defined by IUCN, ranged from 3.8% to 49.3% (mean [95% CI]: 17.3% [9.6, 25.0]). Total migration speed did not differ by season (median: 255 km day-1, range: 182, 295km day-1), despite greater spring travel distances. Birds with longer non-breeding periods, however, migrated north faster. Climate-driven mismatches in migratory timing may be less of a concern for western than for eastern flycatcher populations, given recent con-generic analyses (C. sordidulus, C. virens). However, accelerated high-latitude changes, may nonetheless impact boreal breeders.

For many avian species, spatial migration patterns remain largely undescribed, especially across hemispheric extents. Recent advancements in tracking technologies and high-resolution species distribution models (i.e., eBird Status and Trends products) provide new insights into migratory bird movements and offer a promising opportunity for integrating independent data sources to describe avian migration. Here, we present a three-stage modeling framework for estimating spatial patterns of avian migration. First, we integrate tracking and band re-encounter data to quantify migratory connectivity, defined as the relative proportions of individuals migrating between breeding and nonbreeding regions. Next, we use estimated connectivity proportions along with eBird occurrence probabilities to produce probabilistic least-cost path (LCP) indices. In a final step, we use generalized additive mixed models (GAMMs) both to evaluate the ability of LCP indices to accurately predict (i.e., as a covariate) observed locations derived from tracking and band re-encounter data sets versus pseudo-absence locations during migratory periods and to create a fully integrated (i.e., eBird occurrence, LCP, and tracking/band re-encounter data) spatial prediction index for mapping species-specific seasonal migrations. To illustrate this approach, we apply this framework to describe seasonal migrations of 12 bird species across the Western Hemisphere during pre- and postbreeding migratory periods (i.e., spring and fall, respectively). We found that including LCP indices with eBird occurrence in GAMMs generally improved the ability to accurately predict observed migratory locations compared to models with eBird occurrence alone. Using three performance metrics, the eBird + LCP model demonstrated equivalent or superior fit relative to the eBird-only model for 22 of 24 species-season GAMMs. In particular, the integrated index filled in spatial gaps for species with over-water movements and those that migrated over land where there were few eBird sightings and, thus, low predictive ability of eBird occurrence probabilities (e.g., Amazonian rainforest in South America). This methodology of combining individual-based seasonal movement data with temporally dynamic species distribution models provides a comprehensive approach to integrating multiple data types to describe broad-scale spatial patterns of animal movement. Further development and customization of this approach will continue to advance knowledge about the full annual cycle and conservation of migratory birds.

1. Identifying the processes that determine avian migratory strategies in different environmental contexts is imperative to understanding the constraints to survival and reproduction faced by migratory birds across the planet. 2. We compared the spring migration strategies of Fork‐tailed Flycatchers (Tyrannus s. savana) that breed at south‐temperate latitudes (i.e., austral migrants) vs. tropi‐ cal latitudes (i.e., intratropical migrants) in South America. We hypothesized that austral migrant flycatchers are more time‐selected than intratropical migrants during spring migration. As such, we predicted that austral migrants, which mi‐ grate further than intratropical migrants, will migrate at a faster rate and that the rate of migration for austral migrants will be positively correlated with the onset of spring migration. 3. We attached light‐level geolocators to Fork‐tailed Flycatchers at two tropical breeding sites in Brazil and at two south‐temperate breeding sites in Argentina and tracked their movements until the following breeding season. 4. Of 286 geolocators that were deployed, 37 were recovered ~1 year later, of which 28 provided useable data. Rate of spring migration did not differ significantly between the two groups, and only at one site was there a significantly positive relationship between date of initiation of spring migration and arrival date. 5. This represents the first comparison of individual migratory strategies among con‐ specific passerines breeding at tropical vs. temperate latitudes and suggests that austral migrant Fork‐tailed Flycatchers in South America are not more time‐se‐ lected on spring migration than intratropical migrant conspecifics. Low sample sizes could have diminished our power to detect differences (e.g., between sexes), such that further research into the mechanisms underpinning migratory strategies in this poorly understood system is necessary., Facultad de Ciencias Naturales y Museo

Many migratory species are declining and for most, the proximate causes of their declines remain unknown. For many long-distance Neotropical migratory songbirds, it is assumed that habitat loss on breeding or non-breeding grounds is a primary driver of population declines. We integrated data collected from tracking technology, community science and remote sensing data to quantify migratory connectivity (MC), population trends and habitat loss. We quantified the correlation between forest change throughout the annual cycle and population declines of a long-distance migratory songbird, the Connecticut warbler ( Oporornis agilis , observed decline: −8.99% yr −1 ). MC, the geographic link between populations during two or more phases of the annual cycle, was stronger between breeding and autumn migration routes (MC = 0.24 ± 0.23) than between breeding and non-breeding locations (MC = −0.2 ± 0.14). Different Connecticut warbler populations tended to have population-specific fall migration routes but overlapped almost completely within the northern Gran Chaco ecoregion in South America. Cumulative forest loss within 50 km of breeding locations and the resulting decline in the largest forested patch index was correlated more strongly with population declines than forest loss on migratory stopover regions or on wintering locations in South America, suggesting that habitat loss during the breeding season is a driver of observed population declines for the Connecticut warbler. Land-use practices that retain large, forested patches within landscapes will likely benefit breeding populations of this declining songbird, but further research is needed to help inform land-use practices across the full annual cycle to minimize the impacts to migratory songbirds and abate ongoing population declines.

In socially monogamous species, male reproductive success consists of ‘within-pair’ offspring produced with their socially-paired mate(s), and ‘extra-pair’ offspring produced with additional females throughout the population. Both reproductive pathways offer distinct opportunities for selection in wild populations, as each is composed of separate components of mate attraction, female fecundity, and paternity allocation. Identifying key sources of variance and covariance among these components is a crucial step towards understanding the reproductive strategies that males use to maximize fitness both annually and over their lifetimes. We use 16 years of complete reproductive data from a population of black-throated blue warblers (Setophaga caerulescens) to partition variance in male annual and lifetime reproductive success, and thereby identify if the opportunity for selection varies over the lifetimes of individual males and what reproductive strategies likely favor maximum lifetime fitness. The majority of variance in male reproduction was attributable to within-pair success, but the specific effects of individual components of variance differed between total annual and total lifetime reproductive success. Positive overall lifetime covariance between within-pair and extra-pair components indicates that males able to maximize within-pair success, particularly with double-brooding females, likely achieve higher overall lifetime fitness via both within-pair and extra-pair reproductive pathways.

Ecological “big data” Human activities are rapidly altering the natural world. Nowhere is this more evident, perhaps, than in the Arctic, yet this region remains one of the most remote and difficult to study. Researchers have increasingly relied on animal tracking data in these regions to understand individual species' responses, but if we want to understand larger-scale change, we need to integrate our understanding across species. Davidson et al. introduce an open-source data archive that currently hosts more than 15 million location data points across 96 species and use it to show distinct climate change responses across species. Such ecological “big data” can lead to a wider understanding of change. Science , this issue p. 712

Light‐level geolocator tags use ambient light recordings to estimate the whereabouts of an individual over the time it carried the device. Over the past decade, these tags have emerged as an important tool and have been used extensively for tracking animal migrations, most commonly small birds. Analysing geolocator data can be daunting to new and experienced scientists alike. Over the past decades, several methods with fundamental differences in the analytical approach have been developed to cope with the various caveats and the often complicated data. Here, we explain the concepts behind the analyses of geolocator data and provide a practical guide for the common steps encompassing most analyses – annotation of twilights, calibration, estimating and refining locations, and extraction of movement patterns – describing good practices and common pitfalls for each step. We discuss criteria for deciding whether or not geolocators can answer proposed research questions, provide guidance in choosing an appropriate analysis method and introduce key features of the newest open‐source analysis tools. We provide advice for how to interpret and report results, highlighting parameters that should be reported in publications and included in data archiving. Finally, we introduce a comprehensive supplementary online manual that applies the concepts to several datasets, demonstrates the use of open‐source analysis tools with step‐by‐step instructions and code and details our recommendations for interpreting, reporting and archiving.

Roughly 90% of socially monogamous bird species exhibit some degree of extra-pair paternity (EPP), although the extent and the underlying mechanisms vary among species. We analyzed spatial and demographic patterns of EPP over a 6 year period (2005–2010) as part of a long-term population study of Canada Warblers (Cardellina canadensis (L., 1766)). We identified 12 microsatellite loci used to assess paternity for 185 nestlings from 61 nests. Extra-pair young (EPY) accounted for 41.6% of all nestlings and 57.4% of nests contained at least one EPY. Fewer than half of EPY were sired by males who shared territorial boundaries, and some males sired young in nests 1 km from their territory. The age of social males did not differ from males who cuckolded them. The majority (83%) of EPY were sired by males in older age classes (2+ years old), while

Technological advancements have spurred rapid growth in the study of migratory connectivity, the linkage of individuals and populations between seasons of the annual cycle. The strength of migratory connectivity is a measure of the co-occurrence of populations throughout the annual cycle and can be represented by a correlation of the distances between individuals during one season and another (Mantel correlation, rM). However, measurement of seasonal distributions most often involves incomplete sampling and use of technologies that vary in accuracy and precision. For these reasons, we expanded rM to measure the strength of migratory connectivity (MC) with population-specific transition probabilities that can be derived from many data types and uneven sampling. We explore the sensitivity of MC to possible real-world variation in input parameters: transition probabilities, abundance among regions, spatial arrangement of regions, and sample sizes. We compare MC to rM, present a series of resampling approaches for propagating uncertainty in input values into estimation of MC and rM, and validate the method with bird tracking data. Migratory connectivity was negative when populations are further apart between seasons, positive when populations remain together between seasons, and zero when populations have no patterns in distribution between seasons. MC is most sensitive to transition probabilities and spatial arrangement of regions and performs better than rM when sampling effort is not proportional to true abundance, and when the strength of migratory connectivity varies across the range of the species. Our estimators for MC and rM performed well across several data types. We hope that these methods and the MigConnectivity r package will facilitate quantitative comparisons of migratory connectivity across studies, data types, and taxa to better understand the causes and consequences of the seasonal distributions of populations. Several study design recommendations emerge from our simulations: (1) incorporate abundance among regions when sampling is not proportional; (2) measure transition probabilities across as much of the range as logistically possible; (3) define study regions with either biological information about population delineation, or use discrete study locations as centroids of regions; and (4) estimate and report uncertainty from appropriate sources of sampling and process errors.

Individual responsibility rules (Rules 7, 8, and 9) outline ways each lab member can modulate their own participation to foster lab meeting productivity Productive lab meetings foster a sense of participation, integration, and inclusion among a diverse lab community, and leverage the diversity of experiences and skills of lab members The first step can be for lab members to intentionally discuss implicit biases in a lab meeting (see Rule 3);for example, lab members can facilitate an open dialogue on combating biases within and outside of lab meeting interactions The key to planning productive lab meetings boils down to discussing and determining as a team the answers to why, who, what, where, when, and how: Why are lab meetings important for the functioning of the lab? [Extracted from the article] Copyright of PLoS Computational Biology is the property of Public Library of Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission However, users may print, download, or email articles for individual use This abstract may be abridged No warranty is given about the accuracy of the copy Users should refer to the original published version of the material for the full abstract (Copyright applies to all Abstracts )

The importance of understanding the geographic distribution of the full annual cycle of migratory birds has been increasingly highlighted over the past several decades. However, the difficulty of tracking small birds between breeding and wintering areas has hindered progress in this area. To learn more about Kirtland's warbler Setophaga kirtlandii movement patterns throughout the annual cycle, we deployed archival light-level geolocators across their breeding range in Michigan. We recovered devices from 27 males and analyzed light-level data within a Bayesian framework. We found that most males wintered in the central Bahamas and exhibited a loop migration pattern. In both fall and spring, departure date was the strongest predictor of arrival date, but in spring, stopover duration and migration distance were also important. Though stopover strategies varied, males spent the majority of their spring migration at stopover sites, several of which were located just before or after large ecological barriers. We argue that loop migration is likely a response to seasonal variation in prevailing winds. By documenting a tight link between spring departure and arrival dates, we provide a plausible mechanism for previously documented carry-over effects of winter rainfall on reproductive success in this species. The migratory periods remain the least understood periods for all birds, but by describing Kirtland's warbler migration routes and timing, and identifying locations of stopover sites, we have begun the process of better understanding the dynamics of their full annual cycle. Moreover, we have provided managers with valuable information on which to base future conservation and research priorities.

One of the greatest challenges to informed conservation of migratory animals is elucidating spatiotemporal variation in distributions. Without such information, it is impossible to understand full-annual-cycle ecology and effectively implement conservation actions that address where and when populations are most limited. We deployed and recovered light-level geolocators (n = 34) at 6 breeding sites in North America across the breeding range of a declining long-distance migratory bird, the Prothonotary Warbler (Protonotaria citrea). We sought to determine migratory routes, stopover location and duration, and the location of overwintering grounds. We found that the species exhibits a large-scale, east‒west split in migratory routes and weak migratory connectivity across its range. Specifically, almost all individuals, regardless of breeding origin, overlapped in their estimated wintering location in northern Colombia, in an area 20% the size of the breeding range. Additionally, most of the individuals across all breeding locations concentrated in well-defined stopover locations in Central America while en route to Colombia. Although error inherent in light-level geolocation cannot be fully ruled out, surprisingly much of the estimated wintering area included inland areas even though the Prothonotary Warbler is considered a specialist on coastal mangroves in winter. Based on these results, conservation efforts directed at very specific nonbreeding geographical areas will potentially have benefits across most of the breeding population. Our findings highlight the importance of using modern technologies to validate assumptions about little-studied portions of a species’ annual cycle, and the need to distribute sampling across its range.

Insect migration is globally ubiquitous and can involve continental-scale movements and complex life histories. Apart from select species of migratory moths and butterflies, little is known about the structure of the annual cycle for migratory insects. Using stable-hydrogen isotope analysis of 852 wing samples from eight countries spanning 140 years, combined with 21 years of citizen science data, we determined the full annual cycle of a large migratory dragonfly, the common green darner ( Anax junius ). We demonstrate that darners undertake complex long-distance annual migrations governed largely by temperature that involve at least three generations. In spring, the first generation makes a long-distance northbound movement (further than 650 km) from southern to northern range limits, lays eggs and dies. A second generation emerges and returns south (further than 680 km), where they lay eggs and die. Finally, a third resident generation emerges, reproducing locally and giving rise to the cohort that migrates north the following spring. Since migration timing and nymph development are highly dependent on temperature, continued climate change could lead to fundamental changes in the biology for this and similar migratory insects.

Currently, the deployment of tracking devices is one of the most frequently used approaches to study movement ecology of birds. Recent miniaturization of light‐level geolocators enabled studying small bird species whose migratory patterns were widely unknown. However, geolocators may reduce vital rates in tagged birds and may bias obtained movement data. There is a need for a thorough assessment of the potential tag effects on small birds, as previous meta‐analyses did not evaluate unpublished data and impact of multiple life‐history traits, focused mainly on large species and the number of published studies tagging small birds has increased substantially. We quantitatively reviewed 549 records extracted from 74 published and 48 unpublished studies on over 7,800 tagged and 17,800 control individuals to examine the effects of geolocator tagging on small bird species (body mass, + Publisher's Statement: This is the peer reviewed version of the following article: "Brlík, V, Koleček, J, Burgess, M, et al. Weak effects of geolocators on small birds: A meta‐analysis controlled for phylogeny and publication bias. J Anim Ecol. 2020; 89: 207– 220", which has been published in final form at https://doi.org/10.1111/1365-2656.12962. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.; Read Only Lizenz.

Climate change has been linked to distribution shifts and population declines of numerous animal and plant species, particularly in montane ecosystems. The majority of studies suggest both that low-elevation avian and small mammal species are shifting up in elevation and that high-elevation avian communities are either shifting further upslope or relocating completely with an increase in average local temperatures. However, recent research suggests numerous high elevation montane species are either not shifting or are shifting down in elevation despite the local increasing temperature trends, perhaps as a result of the increased precipitation at high elevations. In this study, we examine common vertebrate species distributions across the Hubbard Brook valley in the White Mountain National Forest, including resident and migratory songbirds and small mammals, in relation to historic spring temperature and precipitation. We found no directional change in distributions through time for any of the species. However, we show that the majority of low-elevation bird species in our study area respond to warm spring temperatures by shifting upslope. All bird species that shifted were long-distance migrants. Each low-elevation migrant species responded differently to warm spring temperatures, through upslope distribution expansion, downslope distribution contraction, or total distribution shift upslope. In contrast, we found a majority of high-elevation bird species and both high- and low-elevation mammal species did not shift in response to spring temperature or precipitation and may be subject to more complex climate trends. The heterogeneous response to climate change highlights the need for more comprehensive studies on the subject and careful consideration for appropriate species and habitat management plans in northeastern montane regions.

Understanding migratory connectivity is critical for interpreting population dynamics, seasonal interactions, and for the implementation of conservation strategies of migratory species. We evaluated the migratory connectivity of a Neotropical migratory songbird, the Ovenbird (Seiurus aurocapilla) using archival light-level geolocators deployed at two breeding and four nonbreeding locations while incorporating Ovenbird abundance as prior information using Bayes' Rule. We also included band recoveries submitted to the United States Geological Survey's Bird Banding Laboratory to assess connectivity of areas where geolocators were not deployed. We created a probabilistic map of origin for each capture site and mapped spring migration routes between nonbreeding and breeding locations. We found a complete separation of eastern and western populations of Ovenbirds throughout the annual cycle. Breeding Ovenbirds from western Canada spent the nonbreeding season throughout Central America and migrated through central North America during spring migration. Birds breeding in the northeastern United States were distributed throughout the central Greater Antilles in the Caribbean and migrated through eastern North America during spring migration. Fall migration routes were not included because the timing of migration coincided with fall equinox when latitudinal estimates are unreliable. However, longitudinal estimates suggest no overlap between eastern and western populations during fall migration. Ovenbirds with geolocators attached in Jamaica bred in the northeastern United States with the highest posterior probability of origin found in Massachusetts, while Ovenbirds captured in Florida and Puerto Rico bred primarily in the mid-Atlantic. Incorporating Ovenbird abundance as a prior into geolocator estimates decreased the area of origin by 90.37% ± 1.05% (mean ± SE) for the breeding season and 62.30% ± 1.69% for the nonbreeding season, compared to geolocator estimates alone. Ovenbirds exhibited strong migratory connectivity between breeding and nonbreeding season, which has important implications for various aspects of the ecology, evolution, and conservation.

The objectives of this study were to describe and evaluate potential drivers of genetic structure in Canadian breeding populations of the Ovenbird, Seiurus aurocapilla. We performed genetic analyses on feather samples of individuals from six study sites using nuclear microsatellites. We also assessed species identity and population genetic structure of quill mites (Acariformes, Syringophilidae). For male Ovenbirds breeding in three study sites, we collected light-level geolocator data to document migratory paths and identify the wintering grounds. We also generated paleohindcast projections from bioclimatic models of Ovenbird distribution to identify potential refugia during the last glacial maximum (LGM, 21,000 years before present) as a factor explaining population genetic structure. Birds breeding in the Cypress Hills (Alberta/Saskatchewan) may be considered a distinct genetic unit, but there was no evidence for genetic differentiation among any other populations. We found relatively strong migratory connectivity in both western and eastern populations, but some evidence of mixing among populations on the wintering grounds. There was also little genetic variation among syringophilid mites from the different Ovenbird populations. These results are consistent with paleohindcast distribution predictions derived from two different global climate models indicating a continuous single LGM refugium, with the possibility of two refugia. Our results suggest that Ovenbird populations breeding in boreal and hemiboreal regions are panmictic, whereas the population breeding in Cypress Hills should be considered a distinct management unit. Natural Sciences and Engineering Research Council of Canada (NSERC); Alberta Conservation Association; NSERC Postgraduate Scholarship; Queen Elizabeth II Graduate Scholarship; University of Alberta; Canadian Circumpolar Institute; Northern Scientific Program This is an electronic version of an article which was originally published as: Haché, S., Bayne, E.M., Villard, M.-A., Proctor, H., Davis, C.S., Stralberg, D., … Krikun, R. (2017). Phylogeography of a migratory songbird across its Canadian breeding range: Implication for conservation units. Ecology and Evolution, 1-11, which has been published at http://dx.doi.org/10.1002/ece3.3170. https://viuspace.viu.ca/bitstream/handle/10613/5027/Gorrell.EE.Article.pdf?sequence=5

In their 2015 Current Biology paper, Streby et al. [1] reported that Golden-winged Warblers (Vermivora chrysoptera), which had just migrated to their breeding location in eastern Tennessee, performed a facultative and up to “>1,500 km roundtrip” to the Gulf of Mexico to avoid a severe tornadic storm. From light-level geolocator data, wherein geographical locations are estimated via the timing of sunrise and sunset, Streby et al. [1] concluded that the warblers had evacuated their breeding area approximately 24 hours before the storm and returned about five days later. The authors presented this finding as evidence that migratory birds avoid severe storms by temporarily moving long-distances. However, the tracking method employed by Streby et al. [1] is prone to considerable error and uncertainty. Here, we argue that this interpretation of the data oversteps the limits of the used tracking technique. By calculating the expected geographical error range for the tracked birds, we demonstrate that the hypothesized movements fell well within the geolocators’ inherent error range for this species and that such deviations in latitude occur frequently even if individuals remain stationary.

Territories provide important breeding and nonbreeding resources for many bird species. Most songbird territory research has been conducted in temperate regions during the breeding season,...

Migratory connectivity for small migratory passerines has been quantified primarily with stable hydrogen isotopes in feathers (δ2HF) because, until recently, we lacked the technology to track small organisms over long distances. Direct tracking of small passerines throughout the annual cycle is now possible with archival light-level geolocators. Our objective was to evaluate whether δ2HF and geolocators produce similar breeding-origin assignments for the same individual birds sampled during the non-breeding season. We estimated breeding origin with geolocators and δ2HF and validated those estimates using a population of Ovenbirds (Seiurus aurocapilla) from a known breeding location at Hubbard Brook Experimental Forest, New Hampshire. We also deployed geolocators on Ovenbirds in Jamaica and Florida during March 2010–2011. We performed stable hydrogen isotope analysis on feathers of birds whose geolocators we recovered (Jamaica: n = 9; Florida: n = 3). Probabilistic assignments of δ2HF that accoun...

Habitat selection by migratory bird species affects their fitness. Studies of populations with marked individuals of known reproductive performance provide the greatest insight on the relationship between a species and the range of habitats it occupies. Canada Warblers (Wilsonia canadensis) have not been intensively investigated at the population level, despite significant regional declines in their numbers over the past 40 years (e.g., 4.6% year−1 in New Hampshire). We mapped 92 male territories over four years and quantified habitat structure and habitat composition for territories and nonterritory areas. Analyses revealed more shrubs (stems and foliage), more perch trees, and lower canopy height on territories. Birds returned at an average rate of 52.0 ± 2.96% (SE) and exhibited average between-year shifts of 32 m in territory locations. Over the four years, males had high pairing success (91.0 ± 5.61%). Three-quarters of paired males fledged at least one young. Pairing and fledging success di...

The Canada Warbler (Wilsonia canadensis) is currently in decline in the northeastern United States and basic demographic parameters remain to be described. We studied marked populations (76 ASYs, 14 SYs, and 2 of unknown age) of Canada Warblers on two study sites from 2003 to 2006. We mapped 92 territories (including males returning in multiple years) of 71 males using handheld GPS and ArcMap. We compared the pairing and fledging success of older and younger males on both sites, a red maple (Acer rubrum) swamp and a young forest intensively harvested in 1985 with ∼10% residual standing trees used by males as song perch trees. Both sites had a high proportion of ASYs (84% ASY for all territorial males, 77.5% of all males including non-territorial individuals). Both pairing (91%) and fledging (78%) success was comparatively high suggesting these two sites were of high value to this species. A higher proportion of SYs were transients. Pairing success was lower for younger males which established ter...

For the first time, we use a small archival global positioning system (GPS) tag to identify and characterize non-breeding territories, quantify migratory connectivity and identify population boundaries of Ovenbirds (Seiurus aurocapilla), a small migratory songbird, captured at two widely separated breeding locations. We recovered 15 (31%) GPS tags with data and located the non-breeding territories of breeding Ovenbirds from Maryland and New Hampshire, USA (0.50 ± 0.15 ha, mean ± SE). All non-breeding territories had similar environmental attributes despite being distributed across parts of Florida, Cuba and Hispaniola. New Hampshire and Maryland breeding populations had non-overlapping non-breeding population boundaries that encompassed 114,803 and 169,233 km2, respectively. Archival GPS tags provided unprecedented pinpoint locations and associated environmental information of tropical non-breeding territories. This technology is an important step forward in understanding seasonal interactions and ultimately population dynamics of populations throughout the annual cycle.

In East Africa, areas of interspersed savanna and woodland between large preserves, such as National Parks, act as important corridors for migrating wildlife. Ndarakwai ranch serves as a wildlife corridor, in particular for the African elephant (Loxodonta africana). We compared browsing intensity on two species of Acacia by measuring elephant damage in 2002 and 2004, especially as it relates to the proximity of individual trees to a permanent water hole. We found a significant negative correlation between damage to both A. tortilis and A. mellifera and their distance from the water hole, as well as significantly greater damage on A. mellifera. The use of this wooded site appears to have declined, as measured by the significantly lower abundance of elephant scat on the site in 2004 compared to 2002.

Multiple regions in East Africa face challenges due to increased rates of resource consumption and species extinction. We examined how well community–based conservation minimizes habitat loss for wildlife and marginalization of under–represented people. Using ecological field work and ethnographic techniques, we focused on how current land use in the Usambara Mountains, Tanzania, affects the ecology and social fabric of the area. We found low recruitment potential of non–native agricultural crops into adjacent forest reserves. We also found that certain agricultural practices that increase sustainability are slowly being integrated while others are still met with resistance. Communication between stakeholders has begun; however, without cooperation amongst key players the long–term future for wildlife and local people will be increasingly threatened as resource pressure intensifies.

We used radiotelemetry to quantify habitat and spatial use patterns of neighboring Louisiana Waterthrush (Parkesia motacilla) along two streams in the Caribbean National Forest in Puerto Rico during 2005–2007. Home range sizes varied with younger birds having larger home ranges and core areas than older birds. All birds occupied some length of stream but a wide range of off-stream habitats were also used. Off-stream habitats included a range of disturbance from residential areas to small saturated pastures. Neighbors exhibited a wide range of overlap in home ranges (x¯ = 20%) and older birds had more overlap than younger birds. The greatest percent of foraging time was along streams (64.4%) followed by muddy substrate (26.5%), housing developments (7.4%), and roads (1.7%). The greater proportion of time foraging along streams indicates this is the preferred habitat for this species. Use of off-stream habitat indicates a strategy of exploiting food-rich ground substrates, and in particular those...

Archived version of the supplemental online manual on light-level geolocator analyses. Note, that the manual is constantly updated and released on http://geolocationmanual.vogelwarte.ch