MARINE MAMMAL COMMISSION — Annual Report for 1991 



Hawaii Sea Grant College Program, and Hale Kohola/ 

 Whaler's Village. 



Also relevant to humpback whales in Hawaii are 

 recent efforts to develop population models that would 

 permit improved assessments of the status of the 

 central North Pacific stock, as well as other North 

 Pacific Ocean stocks of humpback whales. Such 

 models require estimates of vital rates, including age 

 at maturity, reproductive intervals, adult mortality, 

 and calf/juvenile mortality. Of these parameters, 

 estimates of calf and juvenile mortality are the least 

 well documented. In this regard, the report of a 1989 

 International Whaling Commission workshop on 

 photographic identification techniques for whale 

 research noted that it might be possible to estimate 

 humpback whale calf/juvenile mortality from photo- 

 graphs of individually recognizable mother-calf pairs 

 and other whales taken in calving and feeding areas. 



To pursue this idea, the National Marine Mammal 

 Laboratory, in conjunction with researchers studying 

 humpback whales in the North Pacific, began organiz- 

 ing a series of workshops to compare photographic 

 records of humpback whale mother-calf pairs from the 

 Hawaiian calving ground with records of female 

 whales photographed on the feeding grounds in 

 Alaska. The objectives of the workshops were to 

 estimate calf/juvenile mortality and female humpback 

 whale reproductive intervals using photographs. 



The first workshop, supported in part by the 

 Marine Mammal Commission, was held 20-23 No- 

 vember 1991 in Seattle, Washington (see Chapter DC). 

 It focused on cataloguing photographs taken by 

 researchers in Hawaii, Alaska, California, Mexico, 

 Canada, and Japan, and identifying possible data 

 biases. The workshop participants concluded that, 

 while there was sufficient information to develop 

 preliminary estimates of humpback whale calf/juvenile 

 mortality and female reproductive intervals, such 

 analyses could be biased. Possible sources of bias 

 identified by the participants included, among other 

 things, calves that died after they were photographed 

 but were presumed to be alive during the season, and 

 calves that were alive but were missed by researchers. 



A second workshop is planned for April 1992 to 

 compile lists of female humpback whales that were 



photographed with calves of the year during the 

 1991/1992 winter in Hawaii. Photographs of these 

 females will be distributed to researchers in Alaska in 

 order to estimate the numbers of females that were 

 seen in Hawaii with calves and that visited the sum- 

 mer feeding range with their calves during 1992. To 

 the extent possible, these results, along with previous 

 photographs of known female whales with calves will 

 be used to develop preliminary estimates of calf/ 

 juvenile mortality and female reproductive intervals. 



North Atlantic Humpback Whales 



In 1983, Stellwagen Bank, located north of Cape 

 Cod and east of Boston, Massachusetts, was added to 

 the site evaluation list for the National Marine Sanctu- 

 ary Program. To help assess the merits and options 

 for designating the bank as a national marine sanctu- 

 ary, a series of public meetings was held in 1990. On 

 8 February 1991, the Sanctuaries and Reserves 

 Division published a Federal Register notice announc- 

 ing a proposed rule for designating approximately 453 

 square miles of the bank and adjacent waters as the 

 Stellwagen Bank National Marine Sanctuary. The 

 notice also aimounced the availability of a draft 

 management plan and a draft environmental impact 

 statement and requested public and agency comments. 



On 9 April 1991, the Commission, in consultation 

 with its Committee of Scientific Advisors on Marine 

 Mammals, responded. In its comments, the Commis- 

 sion noted that the proposed designation would affect 

 a variety of fish, seabirds, and marine mammals, 

 including five species of endangered whales (i.e., 

 humpback, right, fin, blue, and sei whales). Given 

 the information on the importance of Stellwagen Bank 

 as a feeding and nursing area for humpback, fin, and 

 minke whales, and because right whales also migrate 

 through the area seasonally, the Commission con- 

 curred with the Division's determination that this area 

 is nationally significant and warrants designation as a 

 national marine sanctuary. The Commission recom- 

 mended that the Division proceed with efforts to draft 

 and implement the associated sanctuary management 

 program. 



The Commission also noted, however, that the 

 proposed action did not thoroughly identify or assess 

 possible effects and management needs related to 



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