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Anthropogenic pressures threaten biodiversity, necessitating conservation actions founded on robust ecological models. However, prevailing models inadequately capture the spatiotemporal variation in environmental pressures faced by species with high mobility or complex life histories, as data are often aggregated across species' life histories or spatial distributions. We highlight the limitations of static models for dynamic species and incorporate life history variation and spatial distributions for species and stressors into a trait-based vulnerability and impact model. We use green sea turtles in the Greater Caribbean Region to demonstrate how vulnerability and anthropogenic impact for a dynamic species change across four life stages. By incorporating life stages into a trait-based vulnerability model, we observed life stage-specific vulnerabilities that were otherwise unnoticed when using an aggregated trait value set. Early life stages were more vulnerable to some stressors, such as inorganic pollution or marine heat waves, and less vulnerable to others, such as bycatch. Incorporating spatial distributions of stressors and life stages revealed impacts differ for each life stage across spatial areas, emphasizing the importance of stage-specific conservation measures. Our approach showcases the importance of incorporating dynamic processes into ecological models and will enable better and more targeted conservation actions for species with complex life histories and high mobility. [ABSTRACT FROM AUTHOR]

Aim Location Taxon Methods Results Main Conclusions Competition is often proposed to drive niche segregation along multiple axes in speciose communities. Understanding spatial partitioning of foraging areas is particularly important in species that are constrained to a central place. We present a natural experiment examining variation in habitat preferences of congeneric Southern Ocean predators in sympatry and allopatry. Our aim was to ascertain consistency of habitat preferences within species, and to test whether preferences changed in the presence of the congener.Southern Hemisphere.Multiple colonies of both species within the genus Phoebetria (sooty albatrosses).The two Phoebetria albatrosses breed on islands located from ~37–55°S – sooty albatrosses (P. fusca) in the north and light‐mantled albatrosses (P. palpebrata) in the south – with sympatric overlap at locations ~46–49°S. We analysed GPS and PTT tracks from 87 individuals and multiple remotely sensed environmental variables using GAMs, to determine and compare the key factors influencing habitat preference for each species at each breeding colony.While foraging habitat preferences are consistent in light‐mantled albatrosses, there is divergence of preferences in sooty albatrosses depending on whether they are in sympatry with their congener or in allopatry.This study represents the most comprehensive work on this genus to date and highlights how habitat preferences and behavioural plasticity may influence species distributions under different competitive conditions. [ABSTRACT FROM AUTHOR]

Foraging niche specialization is thought to occur when different members of speciose communities divide resources in either time or space. Here we compared habitat preferences of the congeneric Grey Petrel Procellaria cinerea and White‐chinned Petrel Procellaria aequinoctialis, tracked in the same calendar year using GPS loggers from Gough Island and Bird Island (South Georgia), respectively. We identified periods of active foraging and determined habitat characteristics using remote‐sensing data. Although these highly pelagic species could potentially overlap at sea across large areas, they showed markedly different foraging preferences during their incubation periods, which are temporally offset because Grey Petrels breed during the austral winter. Grey Petrels foraged mostly in pelagic cold‐water areas to the north‐west of South Georgia, whereas White‐chinned Petrels foraged almost exclusively in the warm, shallow waters of the Patagonian Shelf. Within each species, foraging habitat characteristics were highly consistent. Our results demonstrate the diversity of habitat preferences within genera, and provide further evidence that colony‐specific information on habitat preference is crucial to identify important feeding areas for pelagic predators. [ABSTRACT FROM AUTHOR]