Ocean-wide Drivers of Migration Strategies and Their Influence on Population Breeding Performance in a Declining Seabird

Abstract

Which factors shape animals' migration movements across large geographical scales, how different migratory strategies emerge between populations, and how these may affect population dynamics are central questions in the field of animal migration [1] that only large-scale studies of migration patterns across a species' range can answer [2]. To address these questions, we track the migration of 270 Atlantic puffins Fratercula arctica, a red-listed, declining seabird, across their entire breeding range. We investigate the role of demographic, geographical, and environmental variables in driving spatial and behavioral differences on an ocean-basin scale by measuring puffins' among-colony differences in migratory routes and day-to-day behavior (estimated with individual daily activity budgets and energy expenditure). We show that competition and local winter resource availability are important drivers of migratory movements, with birds from larger colonies or with poorer local winter conditions migrating further and visiting less-productive waters; this in turn led to differences in flight activity and energy expenditure. Other behavioral differences emerge with latitude, with foraging effort and energy expenditure increasing when birds winter further north in colder waters. Importantly, these ocean-wide migration patterns can ultimately be linked with breeding performance: colony productivity is negatively associated with wintering latitude, population size, and migration distance, which demonstrates the cost of competition and migration on future breeding and the link between non-breeding and breeding periods. Our results help us to understand the drivers of animal migration and have important implications for population dynamics and the conservation of migratory species.

It’s about time: A synthesis of changing phenology in the Gulf of Maine ecosystem

“…In contrast, preference for ice‐free waters drives harbor seals ( Phoca vitulina concolor ) to move into southern New England during the winter and spring (Baechler, Beck, & Bowen, ; Boehme et al, ; Burns, ). A portion of the North Atlantic right whale population and some seabirds continue to utilize habitats within the GoM during winter (Cole et al, ; Fayet et al, ), although their activities during this time are still largely unknown.…”

“…Some species such as Atlantic puffins and shearwaters (Ardenna spp., Calonectris spp., Puffinus spp.) are believed to overwinter in nearby habitats of the Gulf of St. Lawrence and Bay of Fundy (Fayet et al, 2017;Powers, Wiley, Allyn, Welch, & Ronconi, 2017), while others, such as roseate (Sterna dougallii), common (S. hirundo), and least terns (Sternula antillarum), migrate as far as South America, and Arctic terns (S. paradisaea) to the Southern Ocean (Egevang et al, 2010;Hays et al, 1997;Nisbet, 1984;Thompson et al, 1997;Veit & Petersen, 1993). Leach's storm-petrels are one of the last seabirds to fledge their chicks, starting in August until as late as November, before departing for their wintering grounds including South America and the west coast of Africa (Pollet, Hedd, Taylor, Montevecchi, & Shutler, 2014).…”

“…A portion of the North Atlantic right whale population and some seabirds continue to utilize habitats within the GoM during winter (Cole et al, 2013;Fayet et al, 2017), although their activities during this time are still largely unknown.…”

Breeding status influences timing but not duration of moult in the Northern FulmarFulmarus glacialis

“…Nevertheless, modelling longer-term variations in behaviour using the approach developed by Cherel et al (2016) may provide opportunities to use existing datasets (e.g. Fayet et al 2017) to compare putative moult patterns in individuals of known reproductive status over multiple years and from different colonies.…”

“…Most commonly, geolocation loggers have been used to describe migratory pathways and wintering grounds (e.g. Frederiksen et al 2012, Fayet et al 2017). However, most geolocation devices also have salt water immersion sensors that can be used to test whether moulting seabirds have quasi-flightless periods during which most time is spent on the water (Mackley et al 2011, Gutowsky et al 2014, Cherel et al 2016.…”