Effects of Pharmacologically-Induced Sleep Loss on Parental Care in Arctic-Breeding Songbirds

• Main Author: Payette, Wesley
• Format: Text
• Language: unknown
• Published: TopSCHOLAR® 2020
• Subjects: sleep; birds; parental care; arctic; behavior; Biology; Physiology; Arctic; Plectrophenax nivalis; Snow Bunting; Tundra; Lapland
• Online Access: https://digitalcommons.wku.edu/theses/3185; https://digitalcommons.wku.edu/cgi/viewcontent.cgi?article=4191&context=theses

Sleep loss is well known to impair cognitive function, immunological responses, and general well-being in humans. However, sleep requirements in mammals and birds may vary dramatically, especially with changes in environment. In circumpolar regions with continuous light, sleep requirements may be little, particularly in breeding birds. The effects of sleep loss on several fitness parameters were examined in two species of Arctic-breeding passerine birds: Lapland longspurs (Calcarius lapponicus) and snow buntings (Plectrophenax nivalis). Adult males were implanted during the nestling phase (4 days post-hatch) with osmotic pumps containing an anti-narcolepsy drug, modafinil, to extend the active period for 72 h. Nestlings were weighed on day 2 and day 7 following hatching. In addition, 1-h observations of nestling feeding rates on day 6 post-hatch were conducted. Male longspurs receiving modafinil were less likely to feed nestlings and spend time at the nest but spent more time around the nest than controls. I observed no change in growth rates for longspur nests, but treatment nests tended to fledge a day later. Modafinil had no visible impact on male or female snow bunting behavior; growth rates and time to fledge were similar between groups. I suggest male longspurs require more energy to maintain vigilance at their nests because they build nests in open tundra, where predation is more likely. As snow buntings are functionally cavity nesters, their nests may not require the same levels of vigilance, allowing time for males to rest following provisioning.