Chapter 11 — Species of Special Concern 



tion on fishing effort and incidental take of harbor 

 porpoises in the northwest Atlantic and better data 

 analysis were needed to determine the appropriate 

 action or actions to list the harbor porpoise either as 

 depleted under the Marine Mammal Protection Act or 

 as threatened or endangered under the Endangered 

 Species Act. The Service advised the Commission 

 that: (1) it intended to conduct a status review of the 

 harbor porpoise, including local populations; (2) its 

 Northeast Fisheries Science Center was working with 

 Canadian scientists to obtain information on interac- 

 tions between fisheries and harbor porpoises in the 

 Bay of Fundy; (3) the Atlantic Ocean, Caribbean, and 

 Gulf of Mexico gillnet fisheries for swordfish, tuna, 

 and shark were to be designated as Category I fisher- 

 ies, which would allow for placement of observers on 

 fishing vessels to gain further information on interac- 

 tions with harbor porpoises; (4) information from the 

 Service's west coast regions indicates that the situation 

 in the eastern Pacific is not as serious as in the 

 northwest Atlantic; and (5) if a preliminary analysis of 

 the information received indicates that action under 

 section 114(g)(3) of the Marine Mammal Protection 

 Act is warranted, the Service will request the appro- 

 priate Fishery Management Council(s) to take steps to 

 mitigate any adverse impacts. 



On 12 February 1991, the Service published a 

 notice in the Federal Register announcing its review 

 of the status of harbor porpoises to determine whether 

 any distinct population should be listed under either 

 the Marine Mammal Protection Act or the Endangered 

 Species Act, and requesting information and data on 

 the species' status. On 24 May 1991, the Service 

 published a follow-up notice stating that it had deter- 

 mined that there is no information available to indicate 

 that harbor porpoises off the west coast of the United 

 States are below their optimum sustainable population 

 level, and it was therefore terminating its review of 

 the status of harbor porpoises off the west coast. The 

 notice stated that the Service's review of harbor 

 porpoise status in the northwest Atlantic would 

 continue. 



On 26-28 March 1991, the Service's Northeast 

 Fisheries Science Center held a program review of its 

 Marine Mammals Investigation program. The Marine 

 Mammal Commission participated in the review. 

 Regarding harbor porpoises in the northwest Atlantic 



Ocean, the reviewers recommended, among other 

 things, that: (1) the highest priority be given to 

 obtaining reliable estimates of the harbor porpoise 

 population(s) affected by the groundfish gillnet fishery 

 in the Gulf of Maine and Bay of Fundy, including the 

 estimated number of porpoises taken annually; (2) the 

 Service determine the most cost-effective survey 

 design for obtaining the necessary information; and 

 (3) if necessary, funds from lower priority programs 

 be given over to the harbor porpoise program. The 

 reviewers also noted that, in the near future, the 

 Service should give priority to studies of harbor 

 porpoise stock discreteness, abundance, and diet in the 

 northwest Atlantic Ocean. 



As a related matter, in June 1991, the National 

 Marine Fisheries Service released a draft legislative 

 environmental impact statement on its Proposed 

 Regime to Govern Interactions Between Marine 

 Mammals and Commercial Fishing Operations. The 

 draft statement discusses the incidental take of harbor 

 porpoises in the North Pacific and North Atlantic 

 Oceans. It notes that the population of harbor por- 

 poises off the west coast of North America may be at 

 its optimum sustainable population level, but that the 

 susceptibility of the species to incidental take in 

 coastal gillnet fisheries is nonetheless a cause for 

 concern. The Service therefore recommended that 

 management actions be taken to protect local harbor 

 porpoise populations. 



The Service noted that no optimum sustainable 

 population level has been estimated for the harbor 

 porpoise in the western North Atlantic. Previous 

 estimates of harbor porpoise abundance and estimates 

 of incidental take in the Gulf of Maine, however, 

 suggest that as much as 7.5 percent of the harbor 

 porpoise population is taken incidental to commercial 

 fisheries every year. 



On 23 September 1991, the Marine Mammal 

 Commission provided comments to the National 

 Marine Fisheries Service on the draft legislative 

 environmental impact statement. The Commission 

 noted that: (1) the Service's proposed regime to 

 manage marine mammal-fishery interactions was 

 intended to ensure that no marine mammal population 

 would be adversely affected by levels of take autho- 

 rized under the regime, and (2) this premise appears 



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