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Avian mating strategies play a vital role in the demographic and genetic dynamics of a species and understanding avian reproductive tactics is important to conservation, population management and restoration. Classifications of avian mating strategies have historically been based on direct physical observations and tend to be rigid population‐level generalizations that overlook the variations inherent in most ecological systems. Based on limited empirical field observations, the American Black Swift Cypseloides niger borealis is considered to be a socially monogamous species with pair bonds lasting for many years. To test this hypothesis, we collected genomic DNA samples from banded swifts from six American Black Swift colonies in the western United States from 2004 to 2019 and isolated and developed primers for highly polymorphic microsatellite loci and used them to genotype our samples. Our parentage analysis revealed that sampled females never mated with the same male in subsequent years, suggesting that they are not sexually monogamous with a single partner for many years as previously hypothesized. [ABSTRACT FROM AUTHOR]

The raccoon (Procyon lotor (L., 1758)), a generalist mesocarnivore, has thrived in anthropogenically fragmented landscapes. In this study we utilized 13 microsatellites to analyze the population genetic structure in raccoons occupying an agriculturally fragmented habitat. Our analyses revealed low, but significant, levels of genetic structure ([F.sub.ST] = 0.022, P < 0.001) among 645 raccoons inhabiting 29 spatially distinct habitat patches (neighborhoods). We found no evidence for the presence of either isolation by distance or barriers. However, spatial autocorrelation revealed evidence for social structure at the raccoon-neighborhood scale. About 30% of the variance in levels of social structure among raccoon neighborhoods was explained by effects of habitat-patch size and the percentage of land cover represented by forest around the individual habitat patch. We found strong evidence of sex-biased dispersal using direct (parentage analysis) and indirect (relatedness and assignment indices) genetic estimators. However, our analysis revealed that among dispersing raccoons there was no difference in dispersal distance between sexes and that dispersal events are randomly distributed with respect to distance. Our study provides evidence that demographic and behavioral processes affecting raccoon spatial organization may be most critical at very fine scales of biological organization, such as within individual habitat patches. Le raton laveur (Procyon lotor (L., 1758)), un mesocarnivore generaliste, a prospere dans les paysages fragmentes par l'activite humaine. Nous utilisons, dans notre etude, 13 microsatellites pour determiner la structure genetique de la population chez des ratons laveurs qui vivent dans un habitat fragmente par l'agriculture. Nos analyses revelent des niveaux bas, mais significatifs, de structure genetique ([F.sub.ST] = 0,022, P < 0,001) parmi 645 ratons laveurs vivant dans 29 taches d'habitat distinctes (quartiers). Il n'y a aucune indication d'isolement par la distance, ni de barrieres. Cependant, l'autocorrelation spatiale donne des indications d'une structure sociale a l'echelle des quartiers de ratons laveurs. Environ 30 % de la variance des niveaux de structure sociale entre les quartiers de ratons laveurs s'explique par les effets de la taille de la tache d'habitat et le pourcentage de la couverture du sol autour des taches individuelles d'habitat qui est represente par de la foret. Des estimateurs genetiques directs (analyse de filiation) et indirects (indices de consanguinite et d'attribution) indiquent clairement une dispersion variable en fonction du sexe. Cependant, notre analyse revele que, parmi les ratons laveurs qui se dispersent, il n'y a pas de difference de distance de dispersion en fonction des sexes et que les evenements de dispersion sont repartis au hasard en fonction de la distance. Notre etude fournit des indications que les processus demographiques et comportementaux qui affectent l'organisation spatiale des ratons laveurs peuvent agir de la facon la plus critique aux echelles tres fines de l'organisation biologique, par exemple a l'interieur des taches individuelles d'habitat. [Traduit par la Redaction], Introduction Raccoons (Procyon lotor (L., 1758)) are mesocarnivores that have increased dramatically in numbers and distribution across much of North America, after a decline to relatively low levels in the [...]

The Sage Grouse Centrocercus urophasianus is a species of conservation concern throughout its range in western North America. Since the 1950s, the high count of males at leks has been used as an index for monitoring populations. However, the relationship between this lek‐count index and population size is unclear, and its reliability for assessing population trends has been questioned. We used non‐invasive genetic mark‐recapture analysis of faecal and feather samples to estimate pre‐breeding population size for the Parachute‐Piceance‐Roan, a small, geographically isolated population of Sage Grouse in western Colorado, during two consecutive winters from 2012 to 2014. We estimated total pre‐breeding population size as 335 (95% confidence interval (CI): 287–382) in the first winter and 745 (95% CI: 627–864) in the second, an approximate doubling in abundance between years. Although we also observed a large increase in the spring lek‐count index between those years, high male count data poorly represented mark‐recapture estimates of male abundance in each year. Our data suggest that lek counts are useful for detecting the direction and magnitude of large changes in Sage Grouse abundance over time but they may not reliably reflect small changes in abundance that may be relevant to small populations of conservation concern. [ABSTRACT FROM AUTHOR]

Genetic mark-recapture methods are increasingly being used to estimate demographic parameters in species where traditional techniques are problematic or imprecise. The federally endangered Indiana bat Myotis sodalis has declined dramatically and threats such as white-nose syndrome continue to afflict this species. To date, important demographic information for Indiana bats has been difficult to estimate precisely using traditional techniques such as emergence counts. Successful management and protection of Indiana bats requires better methods to estimate population sizes and survival rates throughout the year, particularly during summer when these bats reproduce and are widely dispersed away from their winter hibernacula. In addition, the familial makeup of maternity colonies is unknown, yet important for understanding local and regional population dynamics. We had four objectives in this study. For the first two objectives we investigated the potential use of DNA from fecal samples (fecal DNA) collected at roosts to obtain genetically based mark-recapture estimates of 1) colony size and 2) survival rates, for an Indiana bat maternity colony in Indianapolis, Indiana. The third objective was to compare our genetically based colony-size estimates with emergence counts conducted at the same roost tree to evaluate the genetic mark-recapture method. Our fourth objective was to use fecal DNA to estimate levels of relatedness among individuals sampled at the roost. In the summer of 2008, we collected fecal pellets and conducted emergence counts at a prominent roost tree during three time periods each lasting 7 or 8 d. We genotyped fecal DNA using five highly polymorphic microsatellite loci to identify individuals and used a robust-design mark-recapture approach to estimate survival rates as well as colony size at the roost tree. Emergence count estimates at the roost tree ranged from 100 to 215, whereas genetic mark-recapture estimates were higher, ranging from 122 to 266 and more precise. Apparent survival was 0.994 (SE ¼ 0.04) between sampling periods suggesting that few bats died or permanently emigrated during the course of the study. Relatedness estimates, r, between all pairs of individuals averaged 0.055 ranging from 0 to 0.779, indicating that most individuals were not closely related. We demonstrate here the promise of using fecal DNA to estimate demographic information for Indiana bats and potentially other bat species. [ABSTRACT FROM AUTHOR]