Attributes / relations provided by
♦ ¹Annual variation in diets, feeding locations and foraging behaviour of gannets in the North Sea: flexibility, consistency and constraint, K. C. Hamer, E. M. Humphreys, S. Garthe, J. Hennicke, G. Peters, D. Grémillet, R. A. Phillips, M. P. Harris, S. Wanless, Mar Ecol Prog Ser 338: 295–305, 2007
♦ ²Marbled Murrelet Food Habits and Prey Ecology, Esther E. Burkett, USDA Forest Service Gen. Tech. Rep. PSW-152. 1995., Chap 22, p. 223-246
♦ ³Flight destinations and foraging behaviour of northern gannets (Sula bassana) preying on a small forage fish in a low-Arctic ecosystem, Stefan Garthea, William A. Montevecchi, Gail K. Davoren, Deep-Sea Research II 54 (2007) 311–320