Workshop to Assess Possible Systems for Tracking Large Cetaceans 

 (A. Bruce, Point Reyes Bird Observatory, Stinson Beach, 

 California; Ebasco Services, Inc., Bellevue, Washington; and 

 S. Montgomery, Woodstock, Virginia) 



Reliable information on daily and seasonal movement pat- 

 terns is necessary to identify breeding, feeding, and other 

 areas that may be critical to the survival of endangered ceta- 

 ceans. Radio-tagging and tracking would be the most cost- 

 effective means for obtaining such information. To date, 

 however, efforts to develop safe and effective systems for 

 radio-tagging and tracking large cetaceans have had limited 

 success. The purposes of this Workshop, sponsored by the 

 Minerals Management Service and organized by the Marine Mammal 

 Commission at the request of the Service, were to: (a) deter- 

 mine what if any problems must be overcome to develop a safe 

 and effective system for long-term tracking and/or relocating 

 large cetaceans; (2) determine how, if possible, to best over- 

 come identified problems; and (3) estimate the time, money, 

 special equipment, and logistic support that would be required 

 to accomplish the identified tasks. The contractors assisted 

 in identifying potential workshop sites, provided logistic 

 support, and prepared the Workshop report. The Workshop was 

 held at the Northwest and Alaska Fisheries Center, Seattle, 

 Washington, on 24-26 February 1987. The Workshop concluded 

 that: (a) tracking radio-tagged whales from satellites offered 

 the best potential for obtaining needed movement and related 

 data; (b) the technology is available to tag and track large 

 cetaceans using existing satellites; (c) problems with attach- 

 ment and retention of tags pose the greatest obstacles; and 

 (d) several possible alternatives to satellite tracking may 

 be useful in some circumstances and thus merit further investi- 

 gation and development. The Workshop report, which described 

 research necessary to determine whether and how the tag attach- 

 ment problems might be overcome, was provided to the Minerals 

 Management Service and is being used to determine how best to 

 facilitate further development and use of technology. 



Ability of Harbor Porpoise to Detect and Avoid Live-Capture 



Weirs 



(K.S. Norris, Ph.D., G.K. Silber, and R.S. Wells, Ph.D., 



University of California, Santa Cruz, California) 



It is not known whether the harbor porpoise being caught 

 and killed in coastal gill net fisheries in central California 

 are part of a small local population or part of a larger popu- 

 lation that ranges north into northern California, Oregon, 

 and Washington. Since radio-tagging and tracking may be the 

 most cost-effective means for obtaining movement data necessary 

 to make this determination, the Commission contracted in 1986 

 for an evaluation of possible methods of capturing, radio- 



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