Meeting Abstract
In Barrow, Alaska (71.2906° N, 156.7886° W) the sun rises on May 10 and does not set again until August 2. This constant light can influence the activity patterns of the animals present; some animals “free-run” with no discernable circadian activity patterns, while a few species are able to maintain a circadian rhythm despite the lack of darkness. One species thought to fall into this latter category is the Snow Bunting (Plectrophenax nivalis), a small songbird that migrates to the high Arctic to breed each summer. To elucidate the activity patterns of this species, we utilized accelerometers that record movement in all 3 axes every second. Eleven adult males outfitted with these accelerometers were housed in an outdoor aviary where they were exposed to natural light and temperature cycles for up to 6 days. Males were able to maintain an activity pattern despite constant light. We also attempted to manipulate sleep in this species by implanting males with melatonin or empty silastic capsules to determine whether supplementation affects paternal care. We banded and tracked males to their nests and then performed feeding observations, nest checks, and monitored nestling growth to determine whether males given melatonin were poorer providers than controls. There were no differences in the feeding rates (Control: 6.3, Melatonin 5.7, p=0.39), or in mean hatchling weight at 3 different time points (2d post-hatch: C:7.0, M: 6.7g, p=0.4; 4-5d post-hatch: C: 12.9, M: 13.5g, p=0.4; day 6-7 post-hatch: C:22.5, M: 21.1g, p=0.35). While a preliminary study, our current results indicate that despite snow buntings maintaining circadian rhythmicity, they seem to be insensitive to melatonin implants when feeding nestlings
