Inter-Research > MEPS > v354 > p289-303  
Marine Ecology Progress Series

via Mailchimp

MEPS 354:289-303 (2008)  -  DOI:

Seabird foraging behaviour indicates prey type

Kyle Hamish Elliott1,*, Kerry Woo2,3, Anthony J. Gaston2,3, Silvano Benvenuti4, Luigi Dall’Antonia5, Gail K. Davoren1

1Department of Zoology, Z320 Duff Roblin Building, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
2Department of Biology, University of Ottawa, 30 Marie Curie, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
3Environment Canada, National Wildlife Research Centre, Carleton University 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
4Dipartimento di Biologia, Ecologia ed Evoluzione, University of Pisa, Via volta 6, 56126 Pisa, Italy
5Istituto di Elaborazione dell’Informazione, C. N. R., Via S. Maria 46, 56126 Pisa, Italy

ABSTRACT: To investigate how a generalist marine predator modifies its foraging behaviour by prey type, we attached time-depth-temperature recorders to chick-rearing thick-billed murres (n = 204) at Coats Island, Nunavut, Canada from 1999 to 2007. Predators varied their behavior along 3 major ‘axes’: foraging effort, prey depth and prey lifestyle (benthic/pelagic). Dive behaviours for different prey—fish doctor, squid, sandlance, amphipods, snakeblenny, daubed shanny, sandlance and Arctic shanny—were discriminated from one another in a discriminant analysis of dive variables and these prey were therefore considered ‘specialist’ prey items. Specifically, amphipods were captured during V-shaped dives near the colony with a slow bird descent rate, squid were captured during deep V-shaped dives in cold water and fish doctor were captured during a long series of U-shaped dives in relatively warm water far from the colony. Arctic shanny and snakeblenny tended to be taken at moderate distances from the colony, with snakeblenny taken at deeper depths. Daubed shanny captures showed a bimodal distribution, with some taken at shallow depths far from the colony and others at deep depths close to the colony. Dive behaviours for Arctic cod, capelin and sculpin overlapped both with each other and the behaviours for specialist prey items and, therefore, were classified as ‘generalist’ prey items. In general, V-shaped dives preceded deliveries of pelagic prey items and U-shaped dives preceded deliveries of benthic prey items. Our results strongly suggest that generalist marine predators use stereotypic behaviour to forage for prey items, based on previous knowledge about what locations/strategies maximized intake for a given prey type.

KEY WORDS: Thick-billed murre · Uria lomvia · Seabirds as indicators · Dive shape · Foraging strategies · Specialization

Full text in pdf format
Cite this article as: Elliott KH, Woo K, Gaston AJ, Benvenuti S, Dall’Antonia L, Davoren GK (2008) Seabird foraging behaviour indicates prey type. Mar Ecol Prog Ser 354:289-303.

Export citation
Share:    Facebook - - linkedIn

 Previous article Next article