Cetaceans of the Central Tyrrhenian Sea: Going, Going ... Gone???
Arcangeli, A., Marini, L. and Crosti, R. 2012. Changes in cetacean presence, relative abundance and distribution over 20 years along a trans-regional fixed line transect in the Central Tyrrhenian Sea. Marine Ecology 34: 112-121.
After describing how, from 1990-1992, dedicated surveys along a fixed-transect in the Central Tyrrhenian Sea had been carried out twice a week (mostly late May through late September) by Marini et al. (1997) - who used passenger ferries as research platforms - Arcangeli et al. go on to describe how they made similar measurements from 2007-2009 "under the same protocol and supervision of the same investigators (Arcangeli et al., 2008), giving the opportunity to compare consistent data over a long period." So did their persistence pay off?
Contrary to what many might have expected, the three Italian researchers report that "total encounter rate in the 1990s (ER = 0.59 ± CI 0.08) was significantly lower (P < 0.01) compared with the 2000s (ER = 0.94 ± CI 0.15)." And they say that sightings of fin whales (Balaenoptera physalus) increased dramatically by fully 300%.
Excited about their positive findings, and hoping to preserve the impressive cetacean populations they encountered, Arcangeli et al. (2012) say that the sea creatures' current abundant presence implies "the consequent necessity of specific legislative acts for cetacean conservation," which is something they are hoping to promote.
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Arcangeli, A., Crosti, R., Marini, L., Poggi, A., Poldi, A., Pulcini, M., Safontas, C., Sdringola, S. and Ukmar, E. 2008. Monitoring cetacean populations over 15 years in Central Tyrrhenian Sea using a non-dedicated ferry as a observation platform. In: Pierce, G.J. and Lick, R. (Eds.). European Research on Cetaceans 22.
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