Lutra 50(1)_Camphuysen_2007

Foraging humpback whale (Megaptera novaeangliae) in the Marsdiep area (Wadden Sea), May 2007 and a review of sightings and strandings in the southern North Sea, 2003-2007

A humpback whale (Megaptera novaeangliae) was observed in the Marsdiep area (western Wadden Sea, The Netherlands), 10-13 May 2007, triggering great media interest and attracting large crowds of spectators to the shore. The animal was foraging in strong tidal currents in a deep gully very close to the dike of Den Helder and in shallow areas of the sandy beach of the island of Texel. Unique characteristics of its dorsal fin are described to facilitate future individual identification of this animal. The feeding techniques, the foraging conditions, feeding areas and the possible prey targeted in the Marsdiep area are described. Humpback whales are very rare in the southern North Sea and have never been before encountered in the Wadden Sea. Recent strandings and sightings along the Dutch and Belgian coasts are summarized. These suggest an increase in numbers frequenting these waters. Historical material suggests that humpback whales have always been very rare and that the recent occurrences are unprecedented.