Preprint volume - SIBM

Pre-print Volume –Oral presentations
Topic 4: THE ELASMOBRANCHS
Tab. 2 – GSA 17, fishermen interviews. Percentage contribution of Elasmobranchs to the total catch
over time.
GSA 17, interviste ai pescatori. Variazione nel tempo del contributo percentuale degli
elasmobranchi alle catture totali.
Mean % Elasmobranch
contribution to the total catch
From 1940’s
to 1960’s
From 1960’s
to 1980’s
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
213
From 1980’s to
present
12.7 (±11.3) 10.9 (±6.3) 5.8 (± 4.7)
As concerns single species, from 1960’s a notable decrease of species like Squalus spp.
and Raja spp was reported. In some cases also a decrease of Mustelus spp. was noticed.
The latest abundant catches of Squalus spp. were reported until the middle of 1970’s.
Conclusions - The results of the interviews performed in both areas closely agreed in
showing a decrease in the catches of elasmobranchs over time. This reduction has been
noticed particularly for some species like Mustelus spp., Squalus spp. and Squatina
spp. As a matter of fact, these species have been included as critically endangered,
endangered or vulnerable species in the IUCN red lists (Cavangh and Gibson, 2007). In
many cases it was reported their complete disappearance. It seems that species like
Mustelus spp. were notably more abundant at the beginning of last Century and in
some areas, as in GSA9, where they were also targets of a specific fishery, until
1960’s. In certain areas, however, an evident decrease of elasmobranchs was already
observed immediately after the Second World War.
Even though these results can be qualified as anecdotal or lacking of scientific value,
this anthropological information could contribute to improve the historical picture of
the fisheries and associated fish communities. On the other hand, the results obtained
from the interviews are validated by several researches and scientific papers (e.g.
Aldebert, 1997; Ferretti et al., 2008).
References
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