Abstract
Vagrancy in birds is an important mechanism contributing to range expansion and the establishment of new breeding populations. However, research on the ecology of vagrant individuals has been limited. From 2005 to 2021, a Red-billed Tropicbird Phaethon aethereus, far outside its usual range, was a summer resident at Seal Island, Maine, USA. In 2020 and 2021, we collected fecal samples from this individual and identified prey types consumed via DNA metabarcoding techniques, using 12S and 18S genes. We identified six fish species in the Red-billed Tropicbird fecal DNA samples, with Atlantic Saury Scomberesox saurus and Atlantic Mackerel Scomber scombrus contributing ~75% of DNA reads. To our knowledge, these two species have not previously been documented in the diet of Red-billed Tropicbirds, yet they were important in both years despite contrasting environmental conditions. Although it is quite possible that this vagrant individual had not encountered either saury or mackerel prior to its extralimital dispersal to the Gulf of Maine, these species share morphological and functional traits with known tropicbird prey elsewhere. Thus, despite occurring > 2,400 km from known breeding sites, this Red-billed Tropicbird was capable of selecting suitable prey in a variable environment.
DOI
http://doi.org/10.5038/2074-1235.53.2.1644
Creative Commons License
Recommended Citation
Kennerley, William L.; Clucas, Gemma V.; Lyons, Donald E.; and Yakola, Keenan C.
(2025)
"What to Eat When Far from Home? A Vagrant Seabird Selects Novel but Analogous Prey,"
Marine Ornithology: Vol. 53
:
Iss.
2
, Article 10.
http://doi.org/10.5038/2074-1235.53.2.1644
Available at:
https://digitalcommons.usf.edu/marine_ornithology/vol53/iss2/10