MARINE MAMMAL COMMISSION - Annual Report for 1998 



recommendations. In its letter to the Service, the 

 Commission recommended that it consult with the 

 vessel operator to develop a protocol on steps to be 

 taken if a whale is struck. The Commission also 

 noted that the potential for hitting whales was not 

 unique to the new ferry, and that if the risk is related 

 to vessel speed, which seems likely, then the potential 

 for hitting whales could increase as the number of 

 high-speed vessels increases. The Commission 

 therefore concluded that there was an urgent need to 

 assess factors related to the likelihood of whales being 

 hit by high-speed as well as conventional vessels. 



In this regard, the Commission noted that whales 

 could be vulnerable to ship strikes for one of three 

 reasons: (1) they are unable to detect approaching 

 ships when they are at the surface in front of an ap- 

 proaching vessel; (2) they are able to detect ships but 

 fail to recognize the danger and take no action to 

 avoid them; or (3) they are able to detect ships and 

 recognize the danger, but they cannot react in time to 

 avoid being hit. These alternative hypotheses would 

 be a useful point from which to begin investigating 

 factors related to ship strikes, and the Commission 

 recommended that the Service consult with the ferry 

 operator and its contractor, as well as the Coast Guard 

 and the Navy, to design and cooperatively fund 

 studies to determine sound levels likely to reach 

 whales in front of various classes of commercial and 

 military ships, and the responses of different whale 

 species to those sounds. 



The National Marine Fisheries Service replied by 

 letter of 3 October 1998 noting that it was working 

 with the ferry operator's contractor to evaluate the 

 ability of onboard observers to detect whales, to 

 examine data on the occurrence of whales along the 

 ferry's route, and to develop a protocol for reporting 

 and searching for whales that may be hit by the ferry. 

 The Service also noted that, within funding con- 

 straints, it would consider support for the recommend- 

 ed studies to examine noise levels and whale behavior 

 in front of different types of ships. 



Another fundamental research need is to improve 

 the detection of right whales in order to warn ships of 

 their presence. As noted above, early warning 

 systems established for this purpose currently rely on 

 aerial observers. Given the length of time whales are 



submerged, aerial observers can detect only about 50 

 percent of the whales present along a survey track, 

 even under the best of conditions. The frequency of 

 poor sighting conditions, the size of areas where right 

 whales may occur, and bad weather ftirther restrict 

 detection by aerial surveys. Recognizing these limits 

 and the importance of finding a better means to detect 

 whales, the Navy took the initiative to examine the 

 use of fixed and towed hydrophone arrays to detect 

 whales by triangulating the position of vocalizing 

 whales. Although the results of research conducted in 

 1996 in the calving grounds demonstrated an ability to 

 locate some animals, whales did not vocalize frequent- 

 ly enough for the approach to be usefiil. 



On 10 July 1997 the Commission wrote to com- 

 mend the Navy for its past efforts and initiative. 

 Because of the limited success of passive acoustic 

 technology, the Commission asked the Navy to 

 consider support for studies to assess the use of active 

 sonar to detect whales. In this regard, the Commis- 

 sion suggested studying the feasibility of placing 

 active sonar units along a ship channel to detect the 

 presence of whales. The Navy expressed a willing- 

 ness to consider this request and, to help determine 

 the merits and scope of such research, the Commis- 

 sion wrote to the Navy on 12 November 1997 sug- 

 gesting that a workshop be held to define what, if 

 any, research might be warranted. The Navy sought 

 further advice on organizing such a workshop from an 

 interagency coordinating committee on ocean noise 

 that includes representatives from the Navy, the 

 National Marine Fisheries Service, the Commission, 

 the Minerals Management Service, and the U.S. 

 Geological Survey. A workshop, scheduled for early 

 October 1998, had to be canceled for procedural 

 reasons and, as of the end of 1998, it was the Com- 

 mission's understanding that the Navy planned to 

 schedule a new meeting early in 1999. 



As a related matter, scientists with the National 

 Marine Fisheries Service's Northeast Fisheries Science 

 Center participated in a study in 1998 that demonstrat- 

 ed an ability to detect whales with active sonar. 



Entanglement of Right Whales in Fishing Gear 



The second principal source of human-related right 

 whale mortality and injury is entanglement in com- 



14 



