Tuesday, May 19, 2009
Harbour Porpoise Study Needed in Quoddy.
The following paper was recently published and reminded me of the need for more focus on harbour porpoise and other "less important" species that call this area "home". We now have projects moving forward that will see tidal turbines in Head Harbour Passage, increased ship passages to Saint John, NB, coastal quarries, port expansion, and the proposed LNG terminals in Passamaquoddy Bay which are getting very active again at FERC with EIA assessments, public meetings and more.
As far as I know, no major work like that outlined below has been done. Imagine, if 39% of the porpoise population in the German North Sea can be affected, what is the potential percentage impact in the restricted waters of Passamaquoddy-West Isles?
Gilles A, Scheidat M, Siebert U (2009). Seasonal distribution of harbour porpoises and possible interference of offshore wind farms in the German North Sea. Marine Ecology Progress Series 383: 295-307
The seasonal distribution of harbour porpoises in the German North Sea was investigated, hot spot areas were identified and the proportion of porpoises potentially affected by the imminent construction of offshore wind farms was estimated. Data were collected during dedicated aerial surveys conducted year-round between 2002 and 2006 following line transect methodology. Survey effort amounted to 44 739 km during which a total of 5121 harbour porpoises was detected, including 258 calves. Our data suggest that porpoises move to distinct areas on a seasonal basis as their biological requirements change. They move into German waters in early spring, reach high numbers in early summer and move out of the area in autumn. The abundance estimates for the German exclusive economic zone and 12 n mile zone were highest in spring (55 048 animals; 95% CI: 32 395 to 10 1671) and summer (49 687 animals; 95% CI: 29 009 to 96 385) and lowest in autumn with 15 394 animals (95% CI: 8906 to 29 470). Important aggregation zones were detected in offshore waters: in spring, 2 hot spots, Borkum Reef Ground and Sylt Outer Reef (SOR), were identified as key foraging areas. In summer, only the large hot spot SOR persisted, causing a strong north–south density gradient. In autumn, porpoises were more evenly distributed. Most mother-calf pairs were observed during spring and summer in the SOR, underlining its importance as a foraging area when reproductive costs are high. Spatial overlap exists between important areas for porpoises and areas where offshore wind farms are currently licensed or planned. The proportion of the national stock possibly exposed to the construction noise of 18 licensed wind farms was estimated applying different scenarios. Within a 20 km zone of responsiveness - as worst case scenario - 39% of the harbour porpoise stock in the German EEZ could be affected during construction.