2-7 April 2006 GDYNIA 20TH CONFERENCE OF THE EUROPEAN CETACEAN SOCIETY
Marine mammals and man in costal ecosystems: can they co-exist?
PRELIMINARY RESULTS OF AN ACOUSTIC SURVEY ACROSS THE MEDITERRANEAN SEA
Podiadis, V. (1), Karpouzli, E.
(2), Genov, T. (3), Sinischalci, F. (4),
Verriopoulos, G. (5), Neofitou, C. (1) and
Exadactylos, A. (1)
(1) University of Thessaly, School
of Agricultural Sciences, Department of
Agriculture, Animal Production and Aquatic
Environment, N. Ionia, Volos 38446, Hellas,
Greece; (2) University of Edinburgh, School
of Geosciences, Drummond Street, EH8 9XP,
Edinburgh, UK; (3) Morigenos - marine mammal
research and conservation society, Jarska
cesta 36/a, 1000 Ljubljana, Slovenia; (4)
OCEANUS onlus, Via Nomentana 175, 00161
Roma, Italy; (5) University of Athens, School
of Sciences, Faculty of Biology, Department
of Zoology and Marine Biology, Panep/poli,
15701 Ilissia, Hellas, Greece
A cetacean survey across the Mediterranean
sea was carried out in October/November
2003, from a 13m, auxiliary powered, sailing
catamaran. The objective of the survey was
to record cetacean species distribution
and abundance, with the aim to contribute
to existing information about cetaceans
in the Mediterranean sea, for their effective
conservation and management. A combination
of passive acoustic methods and visual observations
were employed, with particluar emphasis
on the acoustic detection of the sperm whale
(Physeter macrocephalus). A two-element
stereophonic hydrophone array was towed
on a 100 m cable behind the vessel, sensitive
to frequencies between 100 Hz and 20 kHz.
Acoustic detections were made by listening
for one minute every fifteen minutes, allowing
an index of abundance to be calculated for
sperm whales. Visual observations were carried
out concurent to the acoustic effort during
the day, whenever the sea conditions allowed.
During the survey sperm whales were detected
acoustically on 39 occassions. There were
a total of 36 sightings of six species;
striped dolphin (Stenella coeruleoalba),
Risso's dolphin (Grampus griseus),
short-beaked common dolphin (Delphinus
delphis), bottlenose dolphin (Tursiops
truncatus), long-finned pilot whale
(Globicephala melas), and sperm
whale (Physeter macrocephalus).
The striped dolphin was the species encountered
most frequently, followed by the short-beaked
common dolphin. Sperm whales, bottlenose
dolphins and long-finned pilot whales were
seen twice, while Risso's dolphins were
encountered once. A mixed species association
between striped dolphins, short-beaked common
dolphins and Risso's dolphins was also observed. |
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