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Abstract The ability of individuals to leave a current breeding area and select a future one is important, because such decisions can have multiple consequences for individual fitness, but also for metapopulation dynamics, structure, and long‐term persistence through non‐random dispersal patterns. In the wild, many colonial and territorial animal species display informed dispersal strategies, where individuals use information, such as conspecific breeding success gathered during prospecting, to decide whether and where to disperse. Understanding informed dispersal strategies is essential for relating individual behavior to subsequent movements and then determining how emigration and settlement decisions affect individual fitness and demography. Although numerous theoretical studies have explored the eco‐evolutionary dynamics of dispersal, very few have integrated prospecting and public information use in both emigration and settlement phases. Here, we develop an individual‐based model that fills this gap and use it to explore the eco‐evolutionary dynamics of informed dispersal. In a first experiment, in which only prospecting evolves, we demonstrate that selection always favors informed dispersal based on a low number of prospected patches relative to random dispersal or fully informed dispersal, except when individuals fail to discriminate better patches from worse ones. In a second experiment, which allows the concomitant evolution of both emigration probability and prospecting, we show the same prospecting strategy evolving. However, a plastic emigration strategy evolves, where individuals that breed successfully are always philopatric, while failed breeders are more likely to emigrate, especially when conspecific breeding success is low. Embedding information use and prospecting behavior in eco‐evolutionary models will provide new fundamental understanding of informed dispersal and its consequences for spatial population dynamics.

In many animal species, sexually mature individuals may skip breeding opportunities despite a likely negative impact on fitness. In spatio‐temporally heterogeneous environments, habitat selection theory predicts that individuals select habitats where fitness prospects are maximized. Individuals are attracted to high‐quality habitat patches where they compete for high‐quality breeding sites. Since failures in contests to secure a site may prevent individuals from breeding, we hypothesized that attraction to and competition for high‐quality habitats could shape breeding propensity.Under this hypothesis, we predicted the two following associations between breeding propensity and two key population features. (1) When mean habitat quality in the population increases in multiple patches such that availability of high‐quality sites increases across the population, the resulting decrease in competition should positively affect breeding propensity. (2) When the number of individuals increases in the population, the resulting increase in competitors should negatively affect breeding propensity (negative density dependence).Using long‐term data from kittiwakes Rissa tridactyla, we checked the prerequisite of prediction (1), that availability of high‐quality sites is positively associated with current mean habitat quality in the population (represented by breeding success). We then applied integrated population modelling to quantify annual fluctuations in population mean breeding success, breeding propensity and number of individuals by breeding status (pre‐breeders, breeders, skippers and immigrants), and tested our predictions.Our results showed that breeding propensity acts as an important driver of population growth. As expected, breeding propensity was positively associated with preceding mean habitat quality in the population, and negatively with the number of competitors. These relationships varied depending on breeding status, which likely reflects status dependence in competitive ability.These findings highlight the importance of competition for high‐quality breeding sites in shaping breeding propensity. Thereby, we draw attention towards alternative and complementary explanations to more standard considerations regarding the energetic cost of reproduction, and point to possible side effects of habitat selection behaviours on individual life histories and population dynamics. [ABSTRACT FROM AUTHOR]

The ability of individuals to leave a current breeding area and select a future one is important, because such decisions can have multiple consequences for individual fitness, but also for metapopulation dynamics, structure, and long‐term persistence through non‐random dispersal patterns. In the wild, many colonial and territorial animal species display informed dispersal strategies, where individuals use information, such as conspecific breeding success gathered during prospecting, to decide whether and where to disperse. Understanding informed dispersal strategies is essential for relating individual behavior to subsequent movements and then determining how emigration and settlement decisions affect individual fitness and demography. Although numerous theoretical studies have explored the eco‐evolutionary dynamics of dispersal, very few have integrated prospecting and public information use in both emigration and settlement phases. Here, we develop an individual‐based model that fills this gap and use it to explore the eco‐evolutionary dynamics of informed dispersal. In a first experiment, in which only prospecting evolves, we demonstrate that selection always favors informed dispersal based on a low number of prospected patches relative to random dispersal or fully informed dispersal, except when individuals fail to discriminate better patches from worse ones. In a second experiment, which allows the concomitant evolution of both emigration probability and prospecting, we show the same prospecting strategy evolving. However, a plastic emigration strategy evolves, where individuals that breed successfully are always philopatric, while failed breeders are more likely to emigrate, especially when conspecific breeding success is low. Embedding information use and prospecting behavior in eco‐evolutionary models will provide new fundamental understanding of informed dispersal and its consequences for spatial population dynamics. [ABSTRACT FROM AUTHOR]

The assessments of breeding losses and adverse impacts are crucial in monitoring endangered populations of species such as the eagle owl, Bubo bubo, in Bulgaria. The study population from 45 breeding territories lost 21.7% of laid eggs (n = 761) and 25.2% of nestlings (n = 596) in 327 clutches over 20 years. Out of 11 specified causes, people working or otherwise engaged in activities near nests were the primary reason for destroyed or disturbed nests (35.8%, n = 165 lost eggs, 37.3%, n = 150 lost nestlings). Cannibalism (24.0%), nestlings dying of unknown reasons in the nest (10.0%) and predation (9.9% of lost eggs, 15.3% of lost nestlings) were the most important for the natural decrease of productivity. Breeding in human-made rocky complexes was more successful than in natural sites: treasure hunters destroyed nests only in natural rock formations and predators depredated nests more frequently at these sites. Successful breeding corresponded significantly positively with more difficult access to cliffs and nest places in both categories of rocky complexes. Greater vegetation cover at wider, shady nest sites with easier accessibility showed greater depredation from carnivorous mammals. Nests poorly concealed by vegetation were more vulnerable to the activities of treasure hunters and tourists. We propose biodiversity-friendly management practices of eagle owl breeding territories in relation to analyzed causes of breeding failures. [ABSTRACT FROM AUTHOR]

Abstract The rapid loss of wetlands during the 20th century has caused a severe decline in the biota associated with these habitats. In Europe, the loss of wet grasslands has seriously affected breeding waders, whose numbers have halved in the past 50 years and remaining populations are facing fragmented, low quality habitats. To improve the remaining sites as breeding grounds for these birds, the exact habitat requirements of the species need to be known. Our study was carried out in Boreal Baltic coastal grasslands in Estonia, where land abandonment has been the main reason behind waders' population declines in the past decades. Hence, we focus on partially overgrown fields, aiming to ascertain habitat characteristics determining the breeding site selection of meadow birds, especially the endangered Southern Dunlin (Calidris alpina schinzii). We studied the breeding site selection of four wader species (Southern Dunlin, Common Redshank (Tringa totanus), Northern Lapwing (Vanellus vanellus) and Common Snipe (Gallinago gallinago)) in 23 coastal grasslands over two years. We analysed seven habitat characteristics which could influence the breeding habitat selection of these species. Our study demonstrates that breeding sites of all studied wader species are located closer to wet areas and coastline and further away from woodland. Also, the height of the ground level has an impact on the breeding probability, with lower areas favoured. Concerning the Southern Dunlin, our results show that on sites where the species was absent, suitable breeding sites, regarding the distance from woodland edge, were absent. Thus, reforestation of grasslands may be the key reason behind the poor population status of the species. We also demonstrated that proximity of reed beds did not influence the breeding site selection of waders – a result which contradicts current wet grassland management suggestions. Expanding the open landscape, maintaining a large quantity of wet features suitable for foraging and preventing overgrowth of coastline and lower parts of the meadow makes the habitat optimal for breeding waders. Concerning the growth of the population size and spatial distribution of the Southern Dunlin, removal of woodlands adjacent to grasslands is crucial. [ABSTRACT FROM AUTHOR]

Prospecting for a future breeding site may help individuals decide whether to disperse and where to settle. However, little is known about it because of methodological constraints limiting the acquisition of data at fine spatial and temporal resolutions, especially for individuals that have failed breeding. Using recently developed solar-powered GPS-UHF not requiring the recapture of individuals, we tracked failed breeding black-legged kittiwakes, Rissa tridactyla , nesting in a failed subcolony of a large Norwegian colony from the end of incubation and across the chick-rearing period. As predicted, their movement patterns differed significantly from those of successfully breeding birds tracked simultaneously in a nearby successful subcolony. After 1 week of tracking, all failed breeders rapidly abandoned their nesting cliff and males and females simultaneously increased prospecting visits to other parts of their nesting colony and to neighbouring kittiwake colonies situated 40–50 km away. Conversely, none of the successful breeders prospected over the same period. Our results provide new insights on prospecting movements linked to potential dispersal decisions after breeding failure. They suggest that males and females have similar temporal but different spatial prospecting patterns, possibly due to different costs associated with prospecting and dispersal decisions. They also highlight the need to track more comprehensively the movements linked with breeding habitat selection and dispersal in contrasting environmental conditions to better understand the complex behavioural responses of individuals to breeding failure and their consequences for the spatial dynamics of populations. [ABSTRACT FROM AUTHOR]

Before making dispersal decisions, many species are known to gather social information by prospecting potential future breeding sites, especially when they have failed breeding. So far, the role of current breeding performance on the occurrence of prospecting movements has mainly been studied at limited spatial scales, because of difficulties in tracking free-ranging, fast-moving individuals between distant breeding patches. Little information is thus available on individual behaviour and the spatial extent of prospecting movements in response to breeding failure. To address this issue, black-legged kittiwakes which breeding success was manipulated were tracked with GPS at the end of incubation in two Norwegian colonies. Crucially, and as predicted, prospecting visits to other breeding colonies were recorded in 33% of artificially-failed breeders, but never in successful ones. They occurred at large (40 km) as well as local spatial scales (1 km). Time-budgets of successful and failed breeders differed significantly in terms of trip duration, but also foraging, resting and nesting propensities. These results provide important elements to assess trade-offs between prospecting and other activities. They show that a substantial proportion of failed breeders prospect as early as within a week after failure at the egg stage and suggest that these individuals assess their options of future reproduction by prospecting alternative areas, although dispersal decisions may also involve more complex behavioural processes. Because they link breeding colonies situated tens of kilometres apart, prospecting movements may have critical implications for the dynamics of subdivided populations. [ABSTRACT FROM AUTHOR]

Aim Because of its complexity, dispersal has often been simplified when implemented in models aiming at understanding and predicting population dynamics and persistence in a context of environmental change. In particular, informed dispersal, that is the use of personal and social information to decide whether to leave a natal or current breeding site and where to settle, has seldom been considered. Informed dispersal could nevertheless be critical for predicting population dynamics, structure and persistence, as it could help populations track environmental change. Here, we develop a simulation model to examine the consequences of four dispersal strategies (informed, semi-informed, fixed random dispersal and philopatry) on the dynamics, structure and persistence of a spatially structured population under different environmental scenarios. Methods We built and parameterized a metapopulation dynamic model using a long-lived colonial seabird species as an example, the black-legged kittiwake Rissa tridactyla, breeding on a set of distinct patches. Various scenarios of environmental variability and multiple factors potentially driving natal and breeding dispersal decisions (local habitat quality, individual and conspecific breeding success, personal and social information use) were considered to explore their respective effects. Results Environmental change and dispersal strategies strongly influenced metapopulation dynamics and structure. In spatially variable environments, informed and semi-informed dispersal maintained populations in the long term, whereas philopatry and random dispersal led to extinction. Contrasted dynamics also arose: philopatry led to ecological traps, random and semi-informed dispersal led to source-sink dynamics and informed dispersal drove extinction-recolonization dynamics. Main conclusions This study demonstrates the importance of including informed dispersal in models aiming at predicting the dynamics of spatially structured populations. It also serves to highlight the urgent need to collect more empirical data on dispersal processes to properly parameterize such models. [ABSTRACT FROM AUTHOR]

Territory choice is likely to include sequential sampling at prospective sites, a decision rule for accepting a site, and, when available, use of prior experience. Here, I consider the threshold rule (Real 1990 American Naturalist, 138, 901-917) in which individuals choose the first option that exceeds a preset level of quality and ask how competition for sites limits the choosiness of individuals applying the threshold rule. I then investigate how the addition of site fidelity further influences the evolution of individual choosiness via a threshold rule., I develop an individual-based model that uses a genetic algorithm approach to search for the optimal threshold as an evolutionary stable strategy ( ESS) and equilibrium population size. Territory quality (i.e. likelihood of reproductive success) is spatially heterogeneous. Individuals either use the acceptance threshold alone or together with site fidelity. In the latter strategy, successful breeders that survive remain at their former site as incumbents, whereas unsuccessful breeders move to a new site., Results indicate greater competition for sites increases the acceptance threshold and reduces choosiness even when individuals have perfect information from sampled sites. Incumbency, via site fidelity at successful territories, leads to the evolution of relatively unselective behaviour, the degree to which is influenced by the level of adult survival., Competition for sites and site pre-emption, rather than energetic or mortality costs, may drive the evolution of choosiness. The analysis also highlights the importance of considering coexisting strategies used by individuals and not simply the population. For instance, site fidelity, as a coexisting strategy, can result in an ESS acceptance threshold that is no better than random selection, and yet still safeguard populations from extinction. [ABSTRACT FROM AUTHOR]

Breeding nest site selection is often the first defense against nest predation risk. To be effective, this mechanism requires site‐specific spatial heterogeneity in predator abundance which produces predator‐poor space, prey's ability to assess spatial heterogeneity in risk, and few or weak constraints on the ability to settle in within predator‐poor space. We used a 15‐yr dataset on forested grids that provided extensive records of fledging success of veeries Catharus fuscescens and ovenbirds Seiurus aurocapilla in relation to areas of low and high spatial clustering of an important nest predator, the eastern chipmunk Tamias striatus. Ovenbird nests were built in locations with significantly lower chipmunk clustering at a scale of 900 m2, relative to random locations within our study grids. In contrast, veery nests were built at sites with significantly higher chipmunk clustering relative to random locations. Veery nest site preference for dense shrub patches may increase their vulnerability to chipmunks seeking shrubs to reduce their own vulnerability to predators. Despite interspecific differences in nest placement and avoidance of chipmunk clusters, for both species fledging success was unaffected by surrounding chipmunk activity. This study highlights key differences in the use of predator‐poor space among coexisting species, and highlights the need to consider constraints due to other habitat preferences and large predator communities. [ABSTRACT FROM AUTHOR]