RESUMEN

Density-dependent competition for food influences the foraging behaviour and demography of colonial animals, but how this influence varies across a species' latitudinal range is poorly understood. Here we used satellite tracking from 21 Northern Gannet Morus bassanus colonies (39% of colonies worldwide, supporting 73% of the global population) during chick-rearing to test how foraging trip characteristics (distance and duration) covary with colony size (138-60 953 breeding pairs) and latitude across 89% of their latitudinal range (46.81-71.23° N). Tracking data for 1118 individuals showed that foraging trip duration and maximum distance both increased with square-root colony size. Foraging effort also varied between years for the same colony, consistent with a link to environmental variability. Trip duration and maximum distance also decreased with latitude, after controlling for colony size. Our results are consistent with density-dependent reduction in prey availability influencing colony size and reveal reduced competition at the poleward range margin. This provides a mechanism for rapid population growth at northern colonies and, therefore, a poleward shift in response to environmental change. Further work is required to understand when and how colonial animals deplete nearby prey, along with the positive and negative effects of social foraging behaviour.

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Spatial planning for marine areas of multi-species conservation concern requires in-depth assessment of the distribution of predators and their prey. Northern Gannets Morus bassanus are generalist predators that predate several different forage fishes depending on their availability. In the western North Atlantic, gannets employ different dive tactics while in pursuit of different prey types, performing deep, prolonged U-shaped dives when foraging on capelin (Mallotus villosus), and rapid, shallow, V-shaped dives when foraging on larger pelagic fishes. Therefore, much can be inferred about the distribution and abundance of key forage fishes by assessing the foraging behaviour and space-use of gannets. In this study, we aimed to quantify space-use and to determine areas of suitable foraging habitat for gannets in pursuit of different prey types using habitat suitability models and kernel density utilization distributions. We deployed 25 GPS/Time-depth recorder devices on parental Northern Gannets at Cape St. Mary's, Newfoundland, Canada from 2019 to 2021. To assess the influence of environmental variables on gannets foraging for different prey types, we constructed three different habitat suitability models: a U-shaped dive model, and two V-shaped dive models (early and late chick-rearing). Suitable foraging habitat for capelin, deduced by the U-shaped dive model, was defined by coastal, shallow waters with flat relief and sea surface temperatures (SST) of 11-15° C. Suitable habitat for early V-shaped dives was defined by shallow and coastal waters with steep slope and SST of 12-15°C and ~18°C, likely reflecting the variability in environmental preferences of different prey species captured when performing V-shaped dives. Suitable habitat for late V-shaped dives was defined by shallow coastal waters (<100m depth), as well as waters deeper than 200 m, and by SST greater than 16°C. We show that space-use by gannets can vary both within and between years depending on environmental conditions and the prey they are searching for, with consequences for the extent of potential interaction with anthropogenic activities. Further, we suggest regions defined as suitable for U-shaped dives are likely to be critical habitat of multi-species conservation concern, as these regions are likely to represent consistent capelin spawning habitat.

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RESUMEN

Consistent individual differences in behavior, commonly termed animal personality, are a widespread phenomenon across taxa that have important consequences for fitness, natural selection, and trophic interactions. Animal personality research may prove useful in several conservation contexts, but which contexts remains to be determined. We conducted a structured literature review of 654 studies identified by combining search terms for animal personality and various conservation subfields. We scored the relevance of personality and conservation issues for each study to identify which studies meaningfully integrated the 2 fields as opposed to surface-level connections or vague allusions. We found a taxonomic bias toward mammals (29% of all studies). Very few amphibian or reptile studies applied personality research to conservation issues (6% each). Climate change (21%), invasive species (15%), and captive breeding and reintroduction (13%) were the most abundant conservation subfields that occurred in our search, though a substantial proportion of these papers weakly integrated conservation and animal personality (climate change 54%, invasive species 51%, captive breeding and reintroduction 40%). Based on our results, we recommend that researchers strive for consistent and broadly applicable terminology when describing consistent behavioral differences to minimize confusion and improve the searchability of research. We identify several gaps in the literature that appear to be promising and fruitful avenues for future research, such as disease transmission as a function of sociability or exploration as a driver of space use in protected areas. Practitioners can begin informing future conservation efforts with knowledge gained from animal personality research.

Investigación bibliométrica sobre la integración de la personalidad animal a los contextos de conservación Resumen Las diferencias individuales y constantes en el comportamiento, comúnmente llamadas personalidad animal, son un fenómeno generalizado en los taxones con consecuencias importantes para la aptitud, selección natural e interacciones tróficas. Las investigaciones sobre la personalidad animal pueden ser útiles en varios contextos de conservación, aunque falta determinar cuáles son estos contextos. Realizamos una revisión literaria estructurada de 654 estudios identificados mediante la combinación de los términos de búsqueda para la personalidad animal y varios subcampos de la conservación. Puntuamos la relevancia de la personalidad y los temas de conservación en cada estudio para identificar cuáles de estos integraron significativamente a ambos campos, contrario a las conexiones a nivel superficial o alusiones vagas. Descubrimos un sesgo taxonómico por los mamíferos (29% de todos los estudios). Pocos estudios enfocados en anfibios o reptiles aplicaron un estudio de personalidad a los temas de conservación (6% para cada uno). El cambio climático (21%), las especies invasoras (15%) y la reproducción en cautiverio y las reintroducciones (13%) fueron los subcampos de conservación más abundantes que aparecieron en nuestra búsqueda, aunque una proporción significativa de estos artículos integraron muy poco a la conservación y la personalidad animal (cambio climático 54%, especies invasoras 51%, reproducción en cautiverio y reintroducciones 40%). Con base en nuestros resultados, recomendamos que los investigadores procuren tener terminologías consistentes y de aplicación generalizada cuando describan las diferencias conductuales para así minimizar las confusiones y facilitar la búsqueda durante la investigación. Identificamos varios vacíos en la literatura que prometen ser vías fructíferas para las investigaciones en el futuro, como la transmisión de enfermedades como una función sociable o la exploración como un impulsor del uso del espacio en las áreas protegidas. Los practicantes pueden comenzar por guiar los siguientes esfuerzos de conservación con el conocimiento obtenido de las investigaciones sobre la personalidad animal.

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