TY - JOUR
T1 - Thermal stress during incubation in an arctic breeding seabird
AU - Snell, Katherine R S
AU - Aldará, Jón
AU - Hammer, Sjúrður
AU - Thorup, Kasper
PY - 2024/10
Y1 - 2024/10
N2 - Arctic breeding seabirds have experienced dramatic population declines in recent decades. The population of Arctic skuas (Stercorarius parasiticus) nesting on the Faroe Islands, North Atlantic, breed near the southern extent of their breeding range and are experiencing some of the largest declines. This is thought to be caused in part by increased warming due to climate change and thus, it is becoming critical to investigate the proximate and ultimate effects of the thermal environment on parental physiology, behaviour and breeding success. Behavioural observations at an Arctic skua long-term monitoring colony were undertaken during the 2016 breeding season to determine the frequencies of thermoregulatory panting, and interrupted incubation events. Incubating Arctic skuas showed thermoregulatory behaviour at air temperatures (Ta) of 9 °C, which suggested that they may be operating near their upper thermal tolerance limit. Arctic skuas spent significantly more time panting as Ta increases, wind speed decreases and sun exposure increases. This relationship was apparent even within the narrow ranges of Ta (7.5–15 °C) and wind speed (0-5 ms−1) recorded. Incubation effort was not continuous with birds leaving the nest for up to 100% of the observation block. While we found no relationship between interrupted incubation and environmental conditions, panting was only observed in birds that were simultaneously incubating eggs. These results highlight the constraints on birds during the incubation phase of breeding, and indicate a potential maladaptive behaviour of maintaining incubation despite the increased cost of thermoregulation under warming temperatures in this species. However, the relationship between thermal stress, nest absence and demographic parameters remains unclear, highlighting the importance of longitudinal and/or high-resolution studies that focus on Arctic specialists and the interrelationships between environmental factors, nest absence rates and productivity.
AB - Arctic breeding seabirds have experienced dramatic population declines in recent decades. The population of Arctic skuas (Stercorarius parasiticus) nesting on the Faroe Islands, North Atlantic, breed near the southern extent of their breeding range and are experiencing some of the largest declines. This is thought to be caused in part by increased warming due to climate change and thus, it is becoming critical to investigate the proximate and ultimate effects of the thermal environment on parental physiology, behaviour and breeding success. Behavioural observations at an Arctic skua long-term monitoring colony were undertaken during the 2016 breeding season to determine the frequencies of thermoregulatory panting, and interrupted incubation events. Incubating Arctic skuas showed thermoregulatory behaviour at air temperatures (Ta) of 9 °C, which suggested that they may be operating near their upper thermal tolerance limit. Arctic skuas spent significantly more time panting as Ta increases, wind speed decreases and sun exposure increases. This relationship was apparent even within the narrow ranges of Ta (7.5–15 °C) and wind speed (0-5 ms−1) recorded. Incubation effort was not continuous with birds leaving the nest for up to 100% of the observation block. While we found no relationship between interrupted incubation and environmental conditions, panting was only observed in birds that were simultaneously incubating eggs. These results highlight the constraints on birds during the incubation phase of breeding, and indicate a potential maladaptive behaviour of maintaining incubation despite the increased cost of thermoregulation under warming temperatures in this species. However, the relationship between thermal stress, nest absence and demographic parameters remains unclear, highlighting the importance of longitudinal and/or high-resolution studies that focus on Arctic specialists and the interrelationships between environmental factors, nest absence rates and productivity.
KW - thermoregulation
KW - behaviour
KW - climate change
KW - stercorarius parasiticus
U2 - 10.1016/j.jtherbio.2024.103967
DO - 10.1016/j.jtherbio.2024.103967
M3 - Article
SN - 0306-4565
JO - Journal of Thermal Biology
JF - Journal of Thermal Biology
M1 - 103967
ER -