MARINE MAMMAL COMMISSION - Annual Report for 1995 



Gray Whale 

 (Eschrichtius robustus) 



The gray whale is primarily a coastal species that 

 occurs only in the North Pacific Ocean. Two separate 

 stocks are recognized: a western North Pacific 

 (Korean) stock and an eastern North Pacific (Califor- 

 nia) stock. A few skeletal remains and subfossil 

 specimens, as well as some historical accounts also 

 indicate that gray whales once occurred along the 

 eastern and western coasts of the North Atlantic 

 Ocean as recently as the early 1700s. Along the New 

 England coast, there is a description from the early 

 1700s of "scrag" whales that are thought to have been 

 gray whales. Also, radiocarbon data indicate that the 

 most recent gray whale specimen, found along the 

 coast of New Jersey, died around 1675, well into 

 colonial times. The North Atlantic gray whale 

 therefore may have been the first whale population 

 subject to whaling pressure to have become extinct. 



Pacific gray whales were also severely depleted by 

 commercial whalers in the mid- 1800s and again in the 

 early 1900s. Along the eastern North Pacific, the 

 species was probably reduced to no more than a few 

 thousand animals by the 1940s when it was protected 

 from commercial whaling under international law. 

 The gray whale also was listed as endangered in 1970 

 under the Endangered Species Conservation Act, 

 which preceded the Endangered Species Act of 1973. 



With protection from commercial whaling, the 

 eastern North Pacific gray whale population has made 

 a substantial recovery. This population migrates 

 seasonally along the coast between wintering grounds 

 off the Baja California Peninsula in Mexico, to 

 summer feeding grounds as far north as the Bering 

 and Chukchi Seas between Alaska and Russia. Its 

 current population size is estimated at about 23,000 

 animals and is continuing to increase. Its size is 

 thought to be at or near pre-exploitation levels and, as 

 described in previous annual reports, the eastern 

 North Pacific gray whale population was removed 

 from the U.S. endangered and threatened species list 

 in 1994. 



Because of the eastern North Pacific population's 

 principal occurrence in nearshore waters and bays for 



breeding, migrating, and feeding, gray whales remain 

 vulnerable to effects of various human activities. 

 Gray whales are occasionally entangled in coastal 

 gillnets and also may be affected by offshore oil and 

 gas development, whale-watching, commercial and 

 recreational vessel traffic, coastal development, and 

 salt recovery operations in breeding lagoons. In 

 addition, under subsistence whaling quotas set by the 

 International Whaling Commission, gray whales have 

 been taken by U.S. and Russian Natives. The vast 

 majority have been taken in Russia, where catches 

 between 1966 and 1991 averaged 177 animals per 

 year. In 1994, however, only 44 gray whales were 

 taken in Russia. The current IWC subsistence quota 

 for gray whales is 140 animals per year for 1995 

 1996, and 1997. 



The western North Pacific gray whale population, 

 which migrates annually between summer feeding 

 grounds in the Okhotsk Sea off eastern Russia and 

 winter breeding areas along the South China Coast, 

 has shown no signs of recovery. It numbers perhaps 

 a few hundred animals at most and therefore has 

 remained listed as endangered under the Endangered 

 Species Act. 



Gray Whale Stock Assessment 



Amendments to the Marine Mammal Protection Act 

 in 1994 directed the National Marine Fisheries Service 

 to prepare stock assessments for all marine mammal 

 stocks occurring in U.S. waters to provide a basis for 

 managing the incidental take of marine mammals in 

 commercial fishing operations. Among other things, 

 the assessments are to include estimates of population 

 size and maximum net productivity, determine the 

 level of potential biological removal (not including 

 natural mortality) while still allowing a stock to 

 increase or remain at its optimum sustainable popula- 

 tion level, review information on incidental take 

 levels, and determine if a stock is a "strategic," i.e., 

 one that requires special management attention. 



The Service circulated draft stock assessments, 

 including a draft assessment for eastern North Pacific 

 gray whales, in August 1994. As described in the 

 previous annual report, Commission comments on the 

 draft assessment for gray whales noted that consider- 

 ation should be given to the effects of habitat degrada- 



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