2026/01/27 by Zoe Deakin, Robert J. Thomas, Renata Medeiros +1 · 1 voice
Environmental Science · #Avian ecology and behavior #Animal Ecology and Behavior Studies #Fish Ecology and Management Studies
paper · doi:10.3354/meps15123
Little is known about the behaviour of very small seabirds at sea, largely due to the practical constraints in tracking them remotely; however, GPS tags are now miniaturised enough to track birds as small as the European storm-petrel Hydrobates pelagicus (~26 g). We examined the marine distribution of 28 European storm-petrels on 43 journeys from their breeding colony on Mousa, Shetland, UK. We first compared the observed locations of storm-petrels with a random set of locations matched by distance from the colony. We found that predators, conspecifics, wind and oceanographic variables were important influences on the distribution of storm-petrels. The presence of storm-petrels from the Mousa colony was negatively associated with the predicted abundance of storm-petrels from other colonies, indicating spatial segregation. Presence was also significantly higher at locations with intermediate wind speeds (4-8 m s -1 ), cooler sea surface temperatures (<12°C), chlorophyll concentrations of ~1 mg mg -3 , a relatively shallow seabed depth of ~100 m and at locations with higher seabed terrain roughness. During the daytime, storm-petrels avoided the coastline, where predators were most abundant, but used inshore locations at night. For chick-rearing birds, behavioural classification based on a 2-state hidden Markov model revealed that feeding behaviour took place primarily during daylight, in 2 core areas to the southeast of Shetland. Transit flights took place primarily at dusk, at night and at dawn. These findings provide novel insights into the use of the seascape by European storm-petrels in relation to competition, predation risk and foraging opportunities.