During summer 2008 dedicated vessel based survey were carried out in Northern Ionian waters, in an area of about 3.500 square km, in order to investigate the cetacean presence and distribution. During sighting the photo-identification technique was adopted and information about position, behaviour, group size and interaction with boats were also collected. A total of about 1.000 of nautical miles were navigated in search for cetaceans. For about three weeks, between the 5th and 21st of August, fin whale presence was exceptionally recorded in a small area of nearly 30 square km, Southern of Antipaxos and Northern of Lefkada. A total of 4 sightings with one or two individuals at once were registered. Presence of the species in the area was already known but, differing from previous study, 2008 sightings were located in shallower waters, ranging from 180m to 300m of depth. The observed depth resulted similar to the one of sightings recorded over the continental platform around Lampedusa island, considered as a fin whale feeding winter ground, but it is very different from the ones of the Ligurian sea and previous sightings of the same area, which report the species in deeper waters. The shift in distribution could be due to a change in presence of the prey or to seasonal change in SST of the area.
Exceptional inshore presence of fin whale over the Northern Ionian continental platform
GIACOMA, Cristina;PAPALE, ELENA;
2009-01-01
Abstract
During summer 2008 dedicated vessel based survey were carried out in Northern Ionian waters, in an area of about 3.500 square km, in order to investigate the cetacean presence and distribution. During sighting the photo-identification technique was adopted and information about position, behaviour, group size and interaction with boats were also collected. A total of about 1.000 of nautical miles were navigated in search for cetaceans. For about three weeks, between the 5th and 21st of August, fin whale presence was exceptionally recorded in a small area of nearly 30 square km, Southern of Antipaxos and Northern of Lefkada. A total of 4 sightings with one or two individuals at once were registered. Presence of the species in the area was already known but, differing from previous study, 2008 sightings were located in shallower waters, ranging from 180m to 300m of depth. The observed depth resulted similar to the one of sightings recorded over the continental platform around Lampedusa island, considered as a fin whale feeding winter ground, but it is very different from the ones of the Ligurian sea and previous sightings of the same area, which report the species in deeper waters. The shift in distribution could be due to a change in presence of the prey or to seasonal change in SST of the area.
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