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Nest-site selection influences the survival of care-giving parents and their offspring, but search costs and site availability may limit site choices. Returning to previous nest sites may reduce costs and allow parents to better avoid local predators or access familiar resources. We investigated nest-site fidelity in the Lance-tailed Manakin (Chiroxiphia lanceolata), in which long-lived females raise offspring without male assistance, and found that site choices are responsive to past success but do not predict future outcomes. We compared georeferenced nest locations for the same females detected in consecutive years (245 comparisons for 138 females) and females nesting repeatedly within a year (137 comparisons for 97 females). Females were faithful to nesting sites in 13.9% of comparisons across years and 10.2% within years, and were more likely to nest again in the same site if their offspring fledged. When switching sites, females moved farther if their previous nest failed. Nest-site fidelity was unrelated to mate fidelity or female age. We then assessed whether site choice related to subsequent female survival, nest timing, or nest survival. Contrary to the hypothesis that win-stay-lose-shift tactics improve subsequent nesting outcomes, we found females were no more likely to fledge chicks or survive to a later year after they reused nest sites. However, across years, site-faithful females nested earlier on average than females that switched sites. Early nests were more likely to fledge chicks, and early-nesting females were more likely to renest when their first nesting effort was complete. Win-stay-lose-shift tactics may allow females to avoid areas where predation is likely, but new nest sites are not safer. Females that reuse nest sites benefit from early nest initiation, which both correlates with immediate success and creates potential for longer-term benefits of fidelity through increased opportunities to renest throughout the breeding season. [ABSTRACT FROM AUTHOR]

Studies on seabird biology are usually conducted using local nesting colonies over relatively short periods of time. However, changes in environmental conditions or the current demographic state of a particular population can have a significant impact on the behavior of individuals of certain species, becoming noticeable in long-term research. In the present study, we evaluated the return rate of adults to their breeding sites, the frequency of mate and nest chamber change, and the occurrence of club pairs in four auk species, namely, the crested auklet (Aethia cristatella), the parakeet auklet (A. psittacula), the horned puffin (Fratercula corniculata), and the tufted puffin (F. cirrhata), all of which nested on Talan Island in the Sea of Okhotsk in the years 2008–2015. We compared our results with those obtained for the same colony in 1989–1991 using similar study methods. The breeding success in 1989–1991 was high in all species, while in the years 2008–2015 it was extremely low in both crested and parakeet auklets. Moreover, between these periods, the number of crested and parakeet auklets on the island decreased several times. In tufted puffins it dropped less significantly, whereas the number of horned puffins increased slightly. In the period 2008–2015, 339 crested auklets, 57 parakeet auklets, 38 horned puffins, and 44 tufted puffins were banded individually with colored rings. The average return rate to the colony for the next year during this period amounted to 77, 82, 66, and 85% for these species, respectively. As much as 62% pairs of the crested auklet and 46% pairs of the parakeet auklet broke up the next season, but only half of those pairs of both species broke up probably because of the death of one of the mates. In other cases, both mates reappeared in the colony and formed new pairs. The nest chamber was changed the next year in 16% crested auklets, 12% parakeet auklets, and 22% tufted puffins. From 13 to 18% of crested auklets, parakeet auklets, and horned puffins formed club pairs in addition to the main (breeding) pairs. We also recorded club pairs in the tufted puffin, as well as those in the parakeet auklet and the horned puffin, describing them for the first time. Our study showed that, despite the decline in the numbers of three species and the increased numbers of the fourth one that occurred over 20 years, the percentage of individual returns of all species to the colony the next year remained approximately the same. However, with a low and progressively declining number and a consistently low breeding success in crested and parakeet auklets, the frequency of their pair breakup increased slightly. On the other hand, the probability of nest chamber change for the crested auklet decreased. This may indicate decreased competition for nesting sites after the decline in numbers, as a result of which the majority of birds occupied the most optimal nest chambers. [ABSTRACT FROM AUTHOR]

Abstract Human activity continues to impact global ecosystems, often by altering the habitat suitability, persistence, and movement of native species. It is thus critical to examine the population genetic structure of key ecosystemservice providers across human‐altered landscapes to provide insight into the forces that limit wildlife persistence and movement across multiple spatial scales. While some studies have documented declines of bee pollinators as a result of human‐mediated habitat alteration, others suggest that some bee species may benefit from altered land use due to increased food or nesting resource availability; however, detailed population and dispersal studies have been lacking. We investigated the population genetic structure of the Eastern carpenter bee, Xylocopa virginica, across 14 sites spanning more than 450 km, including dense urban areas and intensive agricultural habitat. X. virginica is a large bee which constructs nests in natural and human‐associated wooden substrates, and is hypothesized to disperse broadly across urbanizing areas. Using 10 microsatellite loci, we detected significant genetic isolation by geographic distance and significant isolation by land use, where urban and cultivated landscapes were most conducive to gene flow. This is one of the first population genetic analyses to provide evidence of enhanced insect dispersal in human‐altered areas as compared to semi‐natural landscapes. We found moderate levels of regional‐scale population structure across the study system (GʹST = 0.146) and substantial co‐ancestry between the sampling regions, where co‐ancestry patterns align with major human transportation corridors, suggesting that human‐mediated movement may be influencing regional dispersal processes. Additionally, we found a signature of strong site‐level philopatry where our analyses revealed significant levels of high genetic relatedness at very fine scales (

Abstract Background Information pertaining to nest-site fidelity and breeding dispersal over successive years can help to better our understanding of how birds respond to nest predation. Methods By using mist nets and tracking the color banded individuals, we investigated nest-site fidelity and breeding dispersal by Common Tailorbirds (Orthotomus sutorius) throughout a year and between successive years in 2017–2018. Results The present study showed that Common Tailorbirds could produce up to four clutches per breeding season. When multiple broods were produced within a year, breeding pairs remained together, and the nest rebuilding rate was up to 92.2%, with only four cases (7.8%) in which birds reused their old nests. The dispersal distance between the nests during multiple breeding was found to be 10.0 ± 10.5 m, and nest-site fidelity within the same year was 90.0%. By the second year of breeding, 76.2% of individuals remained in the original breeding pairs, while for those that did switch partners, the females remained in the nest from the previous year and paired with new males. The dispersal distance between years was 26.5 ± 41.9 m, and nest-site fidelity between different years was 80.1%. There was no significant difference between within-year and between-year dispersal distances. Moreover, there was no significant difference in the dispersal distance of rebuilt nests between birds that had experienced nest predation and those that had not. Conclusions Our findings suggest that Common Tailorbirds maintain a high degree of fidelity to mates and nest-sites, and nest predation had no significant effect on territorial changes or breeding dispersal distance between each breeding attempt.

Abstract Cyclura ricordii is an endemic iguana from Hispaniola Island and is threatened on the IUCN Red List. The main threats are predation by introduced mammals, habitat destruction, and hunting pressure. The present study focused on two nesting sites from Pedernales Province in the Dominican Republic. The hypothesis that natal philopatry influences dispersal and nest‐site selection was tested. Monitoring and sampling took place in 2012 and 2013. Polymorphic markers were used to evaluate whether natal philopatry limits dispersal at multiple spatial scales. Ripley's K revealed that nests were significantly clustered at multiple scales, when both nesting sites were considered and within each nesting site. This suggests a patchy, nonrandom distribution of nests within nest sites. Hierarchical AMOVA revealed that nest‐site aggregations did not explain a significant portion of genetic variation within nesting sites. However, a small but positive correlation between geographic and genetic distance was detected using a Mantel's test. Hence, the relationship between geographic distance and genetic distance among hatchlings within nest sites, while detectable, was not strong enough to have a marked effect on fine‐scale genetic structure. Spatial and genetic data combined determined that the nesting sites included nesting females from multiple locations, and the hypothesis of “natal philopatry” was not supported because females nesting in the same cluster were no more closely related to each other than to other females from the same nesting site. These findings imply that nesting aggregations are more likely associated with cryptic habitat variables contributing to optimal nesting conditions.

Human activity continues to impact global ecosystems, often by altering the habitat suitability, persistence, and movement of native species. It is thus critical to examine the population genetic structure of key ecosystemservice providers across human‐altered landscapes to provide insight into the forces that limit wildlife persistence and movement across multiple spatial scales. While some studies have documented declines of bee pollinators as a result of human‐mediated habitat alteration, others suggest that some bee species may benefit from altered land use due to increased food or nesting resource availability; however, detailed population and dispersal studies have been lacking. We investigated the population genetic structure of the Eastern carpenter bee, Xylocopa virginica, across 14 sites spanning more than 450 km, including dense urban areas and intensive agricultural habitat. X. virginica is a large bee which constructs nests in natural and human‐associated wooden substrates, and is hypothesized to disperse broadly across urbanizing areas. Using 10 microsatellite loci, we detected significant genetic isolation by geographic distance and significant isolation by land use, where urban and cultivated landscapes were most conducive to gene flow. This is one of the first population genetic analyses to provide evidence of enhanced insect dispersal in human‐altered areas as compared to semi‐natural landscapes. We found moderate levels of regional‐scale population structure across the study system (GʹST = 0.146) and substantial co‐ancestry between the sampling regions, where co‐ancestry patterns align with major human transportation corridors, suggesting that human‐mediated movement may be influencing regional dispersal processes. Additionally, we found a signature of strong site‐level philopatry where our analyses revealed significant levels of high genetic relatedness at very fine scales (<1 km), surprising given X. virginica's large body size. These results provide unique genetic evidence that insects can simultaneously exhibit substantial regional dispersal as well as high local nesting fidelity in landscapes dominated by human activity. [ABSTRACT FROM AUTHOR]

We investigated the adult Black Tern (Chlidonias niger) return rate and nest-site fidelity in unstable habitats in the Kaniv reservoir (Middle Dnieper, Ukraine) where a regular weather impact such as heavy rains and storms leads to a destruction of nesting colonies. 278 adult birds were tagged with colored rings in 12 Black Tern colonies during the nesting season in 2012-2019. 44 Black Tern birds were resighted or recaptured in eight colonies. The return rate was 15.8 % and it declined rapidly in 3 years. 29 returning terns were noted within the same colonies where the birds had been tagged initially, 15 ones were seen in other colonies, but the majority of them were found no farther than 2 km from the initial colony. The site fidelity mean rate was 66 %. Olgin colony showed a high nest-site fidelity rate, while it was much lower in others. Such variations occurred because of the loss of first clutches caused by unfavorable weather conditions. In the middle of May, strong waves, storms and heavy rains regularly destroyed nesting colonies located in habitats poorly protected by water plant vegetation. Terns relocated their colonies to build new nesting clutches but commonly not farther then 2 km from their first colonies.

We investigated the return rate and nest-site fidelity of adult Black Terns (Chlidonias niger) in unstable habitats at the Kaniv reservoir, Middle Dnipro (Dnieper), Ukraine, where regular weather extremes such as heavy rains and storms lead to a destruction of nesting colonies. 278 adult birds were tagged with colored rings in 12 Black Tern colonies during the nesting season in 2012-2019. 44 Black Terns were resighted or recaptured in eight colonies. The return rate was 15.8% and it declined rapidly within the first three years after ringing. 29 returning terns were noted within the same colonies where the birds had been tagged initially, 15 ones were seen in other colonies, but the majority of them were found no farther than 2 km from the original colony. The mean site fidelity rate was 66%. Olgin colony showed a high nest-site fidelity rate, while it was much lower in the others. Such variations occurred because of the loss of the first clutches caused by unfavorable weather conditions. In the middle of May high waves, storms and heavy rains regularly destroyed nesting colonies located in habitats poorly protected by water plant vegetation. Terns relocated their colonies to re-nest but commonly not farther than 2 km from their original colonies. [ABSTRACT FROM AUTHOR]

We studied Lesser Kestrels' (Falco naumanni) conditional nest-site fidelity, i.e., fidelity that depends on the outcome of the previous nesting attempt in that site. In particular, we were interested in examining whether individual kestrels practice a Win–Stay/Lose–Shift (WSLS) strategy towards their nest-sites; that is, does the tendency to use the same nest-site increase following a successful nesting season, but decrease following a failure. For that purpose, we documented the use of nest-sites by Lesser Kestrels and the breeding success in these sites during 1998–2003 in the city of Jerusalem (Israel). We found that while Lesser Kestrels do not practice WSLS strategy towards their nest-site, the males (but not the females) do so towards their sub-colony – they tend to stay in the same sub-colony if their nesting was successful, whereas they tend to migrate to a different sub-colony after failure. A possible explanation to this sexual difference in WSLS behavior can arise from the fact that changing a sub-colony entails a change of hunting area. The male, being the main food provider in the Lesser Kestrel, may be more sensitive to this opportunity. [ABSTRACT FROM AUTHOR]

Cyclura ricordii is an endemic iguana from Hispaniola Island and is threatened on the IUCN Red List. The main threats are predation by introduced mammals, habitat destruction, and hunting pressure. The present study focused on two nesting sites from Pedernales Province in the Dominican Republic. The hypothesis that natal philopatry influences dispersal and nest‐site selection was tested. Monitoring and sampling took place in 2012 and 2013. Polymorphic markers were used to evaluate whether natal philopatry limits dispersal at multiple spatial scales. Ripley's K revealed that nests were significantly clustered at multiple scales, when both nesting sites were considered and within each nesting site. This suggests a patchy, nonrandom distribution of nests within nest sites. Hierarchical AMOVA revealed that nest‐site aggregations did not explain a significant portion of genetic variation within nesting sites. However, a small but positive correlation between geographic and genetic distance was detected using a Mantel's test. Hence, the relationship between geographic distance and genetic distance among hatchlings within nest sites, while detectable, was not strong enough to have a marked effect on fine‐scale genetic structure. Spatial and genetic data combined determined that the nesting sites included nesting females from multiple locations, and the hypothesis of "natal philopatry" was not supported because females nesting in the same cluster were no more closely related to each other than to other females from the same nesting site. These findings imply that nesting aggregations are more likely associated with cryptic habitat variables contributing to optimal nesting conditions. [ABSTRACT FROM AUTHOR]

Dispersal is a movement of an individual from its birthplace to a breeding site (natal dispersal) or from a breeding site in one year to a different breeding site in another year (breeding dispersal). Natal and breeding dispersal of the White-throated Dipper (Cinclus cinclus) were studied during the breeding seasons 2009-2018 at the approximately 65 km long tributary system of the Váh river in the Liptov region (northern Slovakia). Altogether 632 nestlings and 73 breeding adults (39 males, 34 females) were ringed within the nest-box system. Males dispersed further from their natal sites (on average 18.8 km) compared with females (on average 4.9 km). The proportion of adult males (17.9%) that occupied the same nest box in one of the following breeding seasons was about half that of females (32.3%). Comparatively lower dispersal of females is relatively rare in birds. We suppose that this may be a result of breeding in nest boxes, which may provide reproductive benefits. [ABSTRACT FROM AUTHOR]

One common strategy to mitigate the loss of natural nest burrows for Burrowing Owls ( Athene cunicularia) from ground-disturbing activities has been the installation of artificial burrows outside the disturbance area. I assessed the effectiveness of artificial burrows as a mitigation tool at two study sites in northern California. Parameters included nesting success at natural and artificial burrows; long-term occupancy rates of maintained and unmaintained artificial burrows; choice of burrow type (natural vs. artificial burrows) by owls raised in artificial burrows; and site fidelity and natal philopatry of Burrowing Owls raised in artificial burrows. I analyzed long-term datasets biologists collected from 1990 through 2012, including demographic data, band resightings, and burrow maintenance records. Nesting success at artificial burrows was significantly higher than at natural burrows at both study sites. At one site, nesting success at artificial burrows was 83% compared to 76% at natural burrows ( P = 0.035); at the other site, nesting success at artificial burrows was 96% compared to 75% at natural burrows ( P = 0.036). Artificial burrows that received annual surface maintenance were occupied for a significantly longer time (2.1 ± 1.9 yr; n = 57) than unmaintained artificial burrows (0.5 ±1.0 yr, n = 51; U = 561, P < 0.001) during the first 8 yr post-installation. Even with surface maintenance, occupancy rates declined from 44% ( n = 25) of burrows occupied during the first year post-installation, to 28% ( n = 15) of burrows occupied during the fourth year post-installation. Based on this decline, regular maintenance of the entire artificial burrow, including tunnel and nest chamber, may be crucial for longer-term use. Of 120 Burrowing Owls raised in maintained artificial burrows and resighted during subsequent breeding seasons, 70% occupied artificial burrows and 30% natural burrows. Only 3% of these owls occupied their natal burrow during the first nesting season post-fledging. Of those owls that were resighted during two or more nesting seasons, almost half (48%) occupied different artificial burrows from one year to the next; therefore, the number of artificial burrows at a management site should be sufficient to provide opportunities for Burrowing Owls to move between nest burrows from year to year. [ABSTRACT FROM AUTHOR]

We studied the use of nest-sites by Griffon Vultures (Gyps fulvus) and the breeding success in these sites during 1998-2002 in Gamla Nature Reserve (Israel). Nest-sites in which a breeding attempt succeeded in fledging a young, were more likely to be occupied by nesting vultures in the following breeding season, than nest-sites that experienced a failure. This suggests that Griffon Vultures in Gamla used a Win-Stay/Lose-Shift strategy regarding nest-site fidelity. [ABSTRACT FROM AUTHOR]

Dispersal is a process that increases genetic diversity and genetic connectivity of populations. We studied the turnover rate of breeding adults and genetic population structure to estimate dispersal in Peregrine Falcons in Finland. We used relatedness estimates among Finnish Peregrine Falcons over a 5-year period, genotyping over 500 nestlings with 10 microsatellite loci to reveal the rate of turnover. Our results reveal a high turnover rate (21.7%) that does not seem to be correlated with the breeding success of the previous year. The extent of population genetic structure and diversity, and possible signs of the population crash during the 1970s, was assessed with a reduced dataset, excluding relatives. We found genetic diversity to be similar to previously studied falcon populations (expected heterozygosity of 0.581) and no population genetic structuring among our sampled populations. We did not find a genetic imprint of the past population bottleneck that the Finnish Peregrine population experienced. We conclude that high dispersal rates are likely to have contributed to maintaining genetic diversity across the landscape, by mixing individuals within the species' distribution in Finland and thus preventing genetic structuring and negative effects associated with the population decline in the 1970s. [ABSTRACT FROM AUTHOR]

Most bees display an array of strategies for building their nests, and the availability of nesting resources plays a significant role in organizing bee communities. Although urbanization can cause local species extinction, many bee species persist in urbanized areas. We studied the response of a bee community to winter-installed human-made nesting structures (bee hotels and soil squares, i.e. 0.5 m deep holes filled with soil) in urbanized sites. We investigated the colonization pattern of these structures over two consecutive years to evaluate the effect of age and the type of substrates (e.g. logs, stems) provided on colonization. Overall, we collected 54 species. In the hotels, two gregarious species, Osmia bicornis L. and O. cornuta Latr. dominated the community (over 87 % of the data). Over 2 years, the age of the soil squares did not affect their level of colonization and the same was true for the hotels with respect to O. bicornis and 'other species'. However, O. cornuta occurred less often and raised fewer descendants in 1-year old hotels than in new ones. Bee nesting was not affected by the soil texture and, among above-ground nesting bees, only O. bicornis showed a preference for some substrates, namely Acer sp. and Catalpa sp. In a context of increasing urbanization and declining bee populations, much attention has focused upon improving the floral resources available for bees, while little effort has been paid to nesting resources. Our results indicate that, in addition to floral availability, nesting resources should be taken into account in the development of urban green areas to promote a diverse bee community. [ABSTRACT FROM AUTHOR]

Females of all seven living species of sea turtles are known to be polyandrous and show multiple paternity. The frequency of multiple paternity varies among species, and among populations of the same species. In the olive ridley sea turtle ( Lepidochelys olivacea ), multiple paternity levels correlate with the abundance of individuals in the mating system, being much higher in arribada rookeries than in solitary nesting sites. We used two highly polymorphic microsatellite markers (Cm84 and Or1) to assess the level of multiple paternity in an olive ridley solitary population nesting in the Gulf of Fonseca, Honduras. We found evidence of multiple paternity in 6 out of 8 clutches (75%), with a minimum number of two fathers in four clutches, and a minimum of three in the remaining two clutches. This high level of multiple paternity in a small solitary population suggests that some of the females nesting in Honduras may be coming from proximal Nicaraguan arribada nesting beaches. Historical evidences and recent satellite telemetry data support this hypothesis. In addition, we show that multiple paternity studies can be effectively performed in the absence of maternal samples, and that pooled DNA samples can be used with results comparable to individual hatchling sampling in multiple paternity analyses. [ABSTRACT FROM AUTHOR]

Understanding why turtles select specific localities to nest over others is important for management and conservation. For some species of freshwater turtle, the same localities are selected year upon year, but it is uncertain whether these localities are selected due to favored environmental conditions, or natal-site homing. The Mary River Turtle (Elusor macrurus) is an endangered freshwater species from Australia, and nesting data gathered between 2004 and 2011 demonstrated that female E. macrurus select to nest in specific localities along the Mary River. Here, we used time-lapse infrared photography and image-identification analysis to assess whether die same individuals returned to the same nesting banks over three consecutive years (nest-site fidelity), and we compared the physical and soil characteristics of nesting areas against other localities along the river where the turtles were not recorded to nest. The photography study illustrated that some females returned to nest at the same locality over consecutive years, whereas others did not; therefore, it is still inconclusive whether E. macrurus exhibits true nest-site fidelity. Preferred nesting areas were all northerly facing and thus exposed to higher levels of solar radiation than nonpreferred areas with similar soil and physical characteristics. Consequently, the preferred nesting areas exhibited significantly greater mean and daily fluctuations in the nest temperature compared with other areas widi dummy nests. We suggest that the warmer nest temperature would speed up embryo development; therefore, female E. macrurus select to nest on northerly facing banks in an attempt to reduce the embryo incubation period. A possible reason for this behavior may be to reduce their exposure to nest-raiding predators. The study highlights importance of key nesting areas along the Mary River for the conservation of E. macrurus. [ABSTRACT FROM AUTHOR]

Although nest prospecting, natal philopatry, and nest-site fidelity have been observed in many alcids, few data demonstrate these behaviors in Marbled Murrelets (Brachyramphus marmoratus). Prior to the 2003 breeding season, we installed a permanent video camera adjacent to a Marbled Murrelet nest site that had been used in 2001 and 2002. Video recordings in 2003 detected the simultaneous presence of 3 murrelets in alternate plumage on the nest branch, once during the incubation period, and once during the chick period. We did not observe aggression, suggesting familiarity between the extra-pair birds and site holders, and possibly avoidance of detection by predators. Without banded individuals we hypothesize extra- pair visitations at an active nest reflect nest-site prospecting, natal philopatry, or nest-site fidelity. [ABSTRACT FROM AUTHOR]

The article discusses a study on breeding and ecology of the Kentish Plover or Charadrius alexandrinus in the Farasan Islands, Saudi Arabia. The study found that incubating plovers in the Farasan Islands have higher preference for nesting under halophytic bushes than in exposed sites. High mate fidelity and nest-site fidelity as well as rare brood desertion were observed. The relationship between extreme hot environment and cooperation between parent plovers in this case is tackled.

From 1999 to 2005 at Zvenigorod Biological Station (Moscow oblast, Russia, 55°44′N, 36°51′E) field studies were performed. Birds were trapped using mist-nets. The Russian Ringing Center provided data collected from 1948 on robins captured outside the Moscow oblast. A total of 5751 robins were trapped and banded in the Moscow oblast. Only two birds (0.03%) were retrapped the following years. Three birds banded in the Moscow oblast were found in other regions. In addition, two robins banded in other countries were caught at Zvenigorod Biological Station. The rate of long-distance recoveries was 0.09%. The Russian Ringing Center reports on three robins banded in other countries and found in the Moscow oblast, and one robin banded in the Moscow oblast and then found in a different country. It was shown that robins born or breed in the Moscow oblast exhibited neither nest-site fidelity nor natal homing, which is the case for other areas. Wintering grounds of robins born or breed in the Moscow oblast are located within a single zone (north-east of Spain, south of France and Italy). This area is also wintering ground for robins from other regions. There exists one route connecting the wintering grounds for robins with the Moscow oblast which birds follow during autumn and spring migrations. It is possible that the Moscow oblast is a nesting area for robins born or breed in the north of Russia (including Finland and the Leningrad oblast). Natal sites and nest sites of robins could be separated by a distance of 1000 km or more. [ABSTRACT FROM AUTHOR]

Despite numerous studies on breeding dispersal, it is still unclear how habitat heterogeneity and previous nesting success interact to determine nest-site fidelity at various spatial scales. In this context, we investigated factors affecting breeding dispersal in greater snow geese ( Anser caerulescens atlanticus), an Arctic breeding species nesting in two contrasting habitats (wetlands and mesic tundra) with variable pattern of snowmelt at the time of settlement in spring. From 1994 to 2005, we monitored the nesting success and breeding dispersal of individually marked females. We found that snow geese showed a moderate amount of nest-site fidelity and considerable individual variability in dispersal distance over consecutive nesting attempts. This variability can be partly accounted for by the annual timing of snowmelt. Despite this environmental constraint, habitat differences at the colony level consistently affected nesting success and settlement patterns. Females nesting in wetlands had higher nesting success than those nesting in mesic tundra. Moreover, geese responded adaptively to spatial heterogeneity by showing fidelity to their nesting habitat, independently of snowmelt pattern. From year to year, geese were more likely to move from mesic to high-quality wetland habitat, regardless of previous nesting success and without cost on their subsequent nesting performance. The unpredictability of snowmelt and the low cost of changing site apparently favour breeding-site dispersal although habitat quality promotes fidelity at the scale of habitat patches. [ABSTRACT FROM AUTHOR]

Nest-site fidelity is associated with previous reproductive success in birds but is thought to be rare among territorial, open-cup nesting passerines. I investigated nest reuse decisions by Spotted Antbirds (Hylophylax naevioides) in central Panama. A quarter of all nest attempts were located at a previously used nest site, often within an extant nest structure. Within a breeding season, pairs preferred to reuse previously successful nest sites overall and were more likely to return to these sites for a consecutive nest attempt than they were to previously depredated nest sites. The fates of two nest attempts at the same location, however, were not associated with each other. The preference of Spotted Antbirds for reusing successful nests may be a short-term strategy to avoid sites recently discovered by predators, as pairs did reuse previously depredated nest sites for later nest attempts and did not prefer successful nest sites from previous breeding seasons. [ABSTRACT FROM AUTHOR]

Human activity continues to impact global ecosystems, often by altering the habitat suitability, persistence, and movement of native species. It is thus critical to examine the population genetic structure of key ecosystemservice providers across human-altered landscapes to provide insight into the forces that limit wildlife persistence and movement across multiple spatial scales. While some studies have documented declines of bee pollinators as a result of human-mediated habitat alteration, others suggest that some bee species may benefit from altered land use due to increased food or nesting resource availability; however, detailed population and dispersal studies have been lacking. We investigated the population genetic structure of the Eastern carpenter bee, Xylocopa virginica, across 14 sites spanning more than 450 km, including dense urban areas and intensive agricultural habitat. X. virginica is a large bee which constructs nests in natural and human-associated wooden substrates, and is hypothesized to disperse broadly across urbanizing areas. Using 10 microsatellite loci, we detected significant genetic isolation by geographic distance and significant isolation by land use, where urban and cultivated landscapes were most conducive to gene flow. This is one of the first population genetic analyses to provide evidence of enhanced insect dispersal in human-altered areas as compared to semi-natural landscapes. We found moderate levels of regional-scale population structure across the study system ( G ' ST  = 0.146) and substantial co-ancestry between the sampling regions, where co-ancestry patterns align with major human transportation corridors, suggesting that human-mediated movement may be influencing regional dispersal processes. Additionally, we found a signature of strong site-level philopatry where our analyses revealed significant levels of high genetic relatedness at very fine scales (<1 km), surprising given X. virginica's large body size. These results provide unique genetic evidence that insects can simultaneously exhibit substantial regional dispersal as well as high local nesting fidelity in landscapes dominated by human activity., (© 2020 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.)