Predicted Harbor Porpoise Bycatch under Potential Mitigation Measure Scenarios

摘要

During the Harbor Porpoise Take Reduction Team meeting in December 2007, questions were raised concerning what the predicted harbor porpoise bycatch would have been in 2005 and 2006 if: (a) the current Harbor Porpoise Take Reduction Plan (HPTRP) was followed (Scenario I); (b) if, in addition, pingers had been used in the entire Northeast gillnet fishery (Scenario II); and (c) if, in addition, the gillnet fishery off of New Jersey, including the Mudhole area, had also used pingers (Scenario III). Using the observed data collected since the implementation of the HPTRP, average bycatch rates of harbor porpoise were estimated for each of these scenarios. Based on these estimated bycatch rates, the average predicted annual harbor porpoise bycatch in 2005 and 2006 under Scenario I (641 animals) would have been slightly above the Potential Biological Removal (PBR) level (610 animals). The average predicted annual bycatch under Scenario II (370 animals) would have been about 61% of PBR, and the predicted bycatch under Scenario III (243 animals) would have been about 40% of PBR. All of the estimates exceed the Zero Mortality Rate Goal (ZMRG) level of 61 animals.