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As offshore wind (OSW) energy expands globally, migratory songbirds are at risk of mortality from collisions with turbine blades, though the magnitude of this threat and which species are most vulnerable, remains poorly understood. Ecological vulnerability indices are commonly used to assess species' susceptibility to harmful factors, with results used to direct scarce research and monitoring resources to species showing relatively high vulnerability. These indices are based on the traits that elevate a species risk to adverse impacts (sensitivity), the overlap in occurrence between a species and the potentially harmful agent (exposure) and the influence of this exposure on the species' local or global persistence (resilience). We modified ecological vulnerability indices for seabirds to assess vulnerability of migratory songbirds to OSW related mortality. As a pertinent case study, we considered songbirds that fly across the Northwest Atlantic during their autumn migration. We utilized readily available information on each species' migratory behaviour, life history, and conservation status to calculate an index score that could range from 1 (lowest vulnerability) to 125 (highest vulnerability). We found scores of 3 to 55.2 for the 101 songbird species evaluated, with New World warblers (Parulidae) over‐represented among the highest scoring species. We found the scores to be sensitive to uncertainty in index components, highlighting the importance of considering scoring uncertainty when evaluating ecological vulnerability indices. Finally, we found that for seven of the top 10 highest scoring species, modest improvements in population trends had the potential to lower the scores substantially. Synthesis and applications. Our methodology is readily applicable to other regions where offshore wind (OSW) development is planned and songbird migration is common, allowing research and monitoring activities to be targeted to species most likely to be negatively affected by OSW facility encounters. [ABSTRACT FROM AUTHOR]

Migration is a prevalent strategy among birds used to track seasonal resources throughout the year. Individual and population‐level migratory movements provide insight to life‐history variation, carry‐over effects, and impacts of climate change. Our understanding of how geographic variation in a species' breeding or wintering grounds can impact migration distances is limited. However, changes in migration distances can have important fitness consequences for individuals and conservation implications for populations, particularly if migratory connectivity is altered during the annual cycle. In this study, we use three decades of data from the United States Geological Survey Bird Banding Laboratory for six migratory species of Arctic and subarctic breeding geese. We employ a Bayesian hierarchical framework to test if the distance between breeding and wintering locations has changed over time, while accounting for the latitude of the breeding grounds. A model that included only a temporal trend estimated the average rate of change in migration distance, across all six species, at −3.0 km/year over the period 1990–2019. Five of the six species showed a significant decrease in migration distances. Including an interaction effect with breeding latitude revealed that the reduction in migration distance was strongest in the southernmost populations for four of the six species. For those species, migration distance in northern populations were all either relatively unchanged or increasing. This indicates that southern breeding populations of geese had a stronger association with the observed spatiotemporal changes in wintering ranges, potentially influenced by a combination of climatic and biotic factors (e.g. resource availability or competitive interactions) that uniquely impact these populations. Abundant, long‐term banding data shows promise for use in illuminating changes in migratory patterns under climate change, leading to improved management and conservation outcomes, from regional to continental scales. [ABSTRACT FROM AUTHOR]

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Objective: Restoration of many populations of anadromous American Shad Alosa sapidissima and river herring (Alewife A. pseudoharengus and Blueback Herring A. aestivalis) has been hampered by the presence of barriers to their spawning migrations and insufficient monitoring of run size. Here, we describe results of a 10‐year (2012–2021) study of American Shad and river herring passage at the Island Farm Weir (IFW), the downstream‐most migration barrier on the Raritan River, New Jersey, United States. Methods: We used passive integrated transponder tags applied to fish that were captured and released downstream of the IFW to estimate passage rates and migration delays associated with upstream movements through an antenna array on a vertical slot fishway within the weir. By combining estimated passage rates with video monitoring of the total numbers of American Shad and river herring transiting the fishway, we estimated the annual run size below the weir. Result: Results suggest that the fishway on the IFW is moderately effective for American Shad (passage rate = 41%; 95% credible interval [CI] = 21–61%) but ineffective for the smaller‐bodied river herring (passage rate = 0.5%, 95% CI = 0–2%; fallback‐adjusted passage rate = 1.1%, 95% CI = 0.0–4.5%). The IFW may have also delayed the spawning migrations of those fish that did pass, with total passage times ranging from 0.4 to 20.9 days (mean ± standard deviation = 8.2 ± 5.3 days) for American Shad and 15.0 days for the one river herring that passed within the same year that it was tagged. Run size estimates during the study period ranged from 103 to 2624 individuals for American Shad and from 1486 to 53,334 for river herring. Conclusion: Restoration of these species in the Raritan River will likely require removal of the IFW or replacement of its current fish passage device with one that increases the passage rates of alosines. Impact statementUsing a combination of electronic tags and video monitoring, we found that a fish passage structure on the Raritan River, New Jersey, works moderately well for the large‐bodied American Shad but passes only a small fraction of the smaller‐bodied river herring. [ABSTRACT FROM AUTHOR]

Reptiles are increasingly of conservation concern due to their susceptibility to habitat loss, emerging disease, and harvest in the wildlife trade. However, reptile populations are often difficult to monitor given the frequency of crypsis in their life history. This difficulty has left uncertain the conservation status of many species and the efficacy of conservation actions unknown. Environmental DNA (eDNA) surveys consistently elevate the detection rate of species they are designed to monitor, and while their use is promising for terrestrial reptile conservation, successes in developing such surveys have been sparse. We tested the degree to which inclusion of surface and soil eDNA sampling into conventional artificial‐cover methods elevates the detection probability of a small, cryptic terrestrial lizard, Scincella lateralis. The eDNA sampling of cover object surfaces with paint rollers elevated per sample detection probabilities for this species 4–16 times compared with visual surveys alone. We readily detected S. lateralis eDNA under cover objects up to 2 weeks after the last visual detection, and at some cover objects where no S. lateralis were visually observed in prior months. With sufficient sampling intensity, eDNA testing of soil under cover objects produced comparable per sample detection probabilities as roller surface methods. Our results suggest that combining eDNA and cover object methods can considerably increase the detection power of reptile monitoring programs, allowing more accurate estimates of population size, detection of temporal and spatial changes in habitat use, and tracking success of restoration efforts. Further research into the deposition and decay rates of reptile eDNA under cover objects, as well as tailored protocols for different species and habitats, is needed to bring the technique into widespread use. [ABSTRACT FROM AUTHOR]

Spatial synchrony, defined as the correlated fluctuations in abundance of spatially separated populations, can be caused by regional fluctuations in natural and anthropogenic environmental population drivers. Investigations into the geography of synchrony can provide useful insight to inform conservation planning efforts by revealing regions of common population drivers and metapopulation extinction vulnerability. We examined the geography of spatial synchrony and decadal changes in these patterns for grassland birds in the United States and Canada, which are experiencing widespread and persistent population declines. We used Bayesian hierarchical models and over 50 years of abundance data from the North American Breeding Bird Survey to generate population indices within a 2° latitude by 2° longitude grid. We computed and mapped mean local spatial synchrony for each cell (mean detrended correlation of the index among neighboring cells), along with associated uncertainty, for 19 species in 2, 26‐year periods, 1968–1993 and 1994–2019. Grassland birds were predicted to increase in spatial synchrony where agricultural intensification, climate change, or interactions between the 2 increased. We found no evidence of an overall increase in synchrony among grassland bird species. However, based on the geography of these changes, there was considerable spatial heterogeneity within species. Averaging across species, we identified clusters of increasing spatial synchrony in the Prairie Pothole and Shortgrass Prairie regions and a region of decreasing spatial synchrony in the eastern United States. Our approach has the potential to inform continental‐scale conservation planning by adding an additional layer of relevant information to species status assessments and spatial prioritization of policy and management actions. Our work adds to a growing literature suggesting that global change may result in shifting patterns of spatial synchrony in population dynamics across taxa with broad implications for biodiversity conservation. [ABSTRACT FROM AUTHOR]

Efforts to monitor and conserve populations and ecosystems in human‐dominated landscapes can benefit from an empirical social–ecological systems approach.Here we illustrate how latent variable structural equation modelling of regional time series data can effectively describe interconnected drivers of population fluctuations in dynamic landscapes and can help to reveal previously unknown system drivers.Using a declining farmland‐dependent bird species (Ammodramus savannarum) in the eastern United States (1994–2015) as a case study, our analysis reveals how farm management decisions drive population fluctuations (R2 = 20%), while management is in turn highly influenced by climate (R2 = 23%–51%), but not by regional conservation spending.Synthesis and applications. Structural equation modelling revealed potential social–ecological pathways for halting regional population declines in a grassland bird, the Grasshopper Sparrow. Lower population growth rates followed years of higher hay yields (~4 percentage points per metric ton increase in hay yield) and later harvests (~2 percentage points per 10‐day delay in harvest). Thus, one pathway for stabilising regional populations could involve compensating farmers for reducing hay harvests, potentially requiring a six‐fold increase in current annual agri‐environmental conservation spending. [ABSTRACT FROM AUTHOR]