FIJN RC, POOT MJM, RIJN SHM VAN, EERDEN MR VAN & BOUDEWIJN TJ (2014) Specialist behaviour of a generalist: a coastal breeding Great Cormorant Phalacrocorax carbo forages exclusively in inland waters. LIMOSA 87 (2): 129-134.

Cormorants are regarded as generalists that opportunistically feed on a variety of fish species with different hunting techniques in diverse habitats. To study habitat use, time budgets and foraging behaviour, in 2012 we deployed GPS loggers on 11 Great Cormorants breeding at a near-coastal colony at Voorne in the northern Delta region, Zuid-Holland. Data of ten loggers could be downloaded. Seven of those birds foraged exclusively at sea. Three other foraged also in inland waters. One female proved to be a specialist feeder in inland shallow ditches and water reservoirs near greenhouse complexes (Figs. 1 & 3), feeding on Roach and other cyprinid fish. The question is why this particular individual chose solely freshwater prey above the energy-rich marine prey. Possibly the lack of competition in combination with well-developed hunting skills for this particular habitat explain this preference

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