96 



Mdiitmah — Our tiring Rcsaurces 



^ 6 



Fig. 2. Actual cniints of bcmhead 

 whales. l978-9U(NOAA 1W4|. 



For further information: 



Michael Payne 



National Marine Fisheries Service 



Office of Protected Resources 



F/PR2 



1335 East-West Highway 



Silver Spring, MD 20910 



78 79 



81 82 83 84 85 

 Year 



87 88 89 90 91 92 93 



10,000. NMFS believes that human influences 

 sueh as ship strikes and net entanglements are 

 affecting about 60% of the population. The 

 agency notes that the annual loss of even a sin- 

 gle right whale has measurable effect on the 

 population, by greatly inhibiting recovery of the 

 species. 



Dolphins and Porpoises 



The coastal migratory stock of Atlantic bot- 

 tlenose dolphin {Tiirsiops inmcutus) is listed as 

 depleted under the MMPA (Table 1). This 

 coastal stock incurred a loss of up to 50% dur- 

 ing a 1987-88 die-off. Long-term trends are 

 unknown, but the stock may require as many as 

 50 years to recover. 



Harbor porpoises (Phocoena phocoeua) 

 occur on both U.S. coasts and are faring rela- 

 tively well. The northwestern Atlantic harbor 

 poipoise is found from Newfoundland, Canada. 

 to Florida. The NMFS 1991-92 population esti- 

 mate of the Gulf of Maine population is 47,200 

 (Table 1 ), but estimates of abundance for other 

 populations do not exist. NMFS has found that 

 harbor porpoise mortality from sink gill-net 

 fisheries along the east coast of North America 

 from Canada to North Carolina appears large 

 compared with the species" natural reproduction 

 rates. Management actions are being taken to 

 address this issue, but long-term trends are 

 unknown. On the west coast. NMFS's com- 

 bined population estimate for northern 

 California, Oregon, and Washington coastal 

 stocks is 45.713. 



The NMFS assesses 10 stocks of eastern 

 tropical Pacific dolphins. Although population 

 trends for most populations cannot be detected, 

 the northeastern stocks of offshore spotted dol- 

 phin and the common dolphin may be declining 

 (Table 2). These two stocks, as well as the east- 

 em spinner and the striped dolphin, are inciden- 

 tally taken in the international fishery for yel- 

 lowfin tuna in the tropical Pacific waters off 



Mexico and Central America. Although mortali- 

 ty has been reduced in recent years, populations 

 are still declining, or at best not increasing. 



Seals and Sea Lions 



According to the NMFS. harbor .seal iPhoca 

 vitulina) populations have increased recently 

 throughout much of their range because of pro- 

 tection by the MMPA. Recent NMFS surveys 

 estimate that at least 26.000 harbor seals inhabit 

 the Gulf of Maine (Table 1 ). Populations of 

 California harbor seals are also increasing; a 

 recent survey resulted in a count of about 23.000 

 harbor seals residing in the Channel Islands and 

 along the California mainland (Table 2). an 

 increase from about 12.000 in 1983. The popu- 

 lation of harbor seals in Oregon and Washington 

 has been estimated at 45.700, and is also 

 increasing. Harbor seal counts in the Central 

 Gulf of Alaska, however, have declined signifi- 

 cantly in the past two decades; numbers are cur- 

 rently estimated by NOAA at 63,000 seals. 



The northern fur seal iCulUtrhinus ursinus) 

 is considered depleted under the MMPA. 

 Production on one of its major breeding areas. 

 Alaska's Pribilof Islands, dropped more than 

 60% between 1955 and 1980, but has since sta- 

 bilized. The cunent population is less than 40% 

 of the mid-1950"s level; no significant trend in 

 the Pribilof Islands population has been noted 

 since 1983 (Table 2). 



The northern sea lion or Steller sea lion 

 [Eiimetopias jiihutiis) is listed as threatened 

 under the ESA. Species numbers have declined 

 shaiply throughout its range in the last 34 years 

 (Table 2). The number of adults and juveniles in 

 U.S. waters dropped from 154.000 in 1960 to 

 40,000 in 1992. a reduction of 73%. Most of 

 this decline occuned in Alaska waters, and is 

 believed due to a combination of factors, 

 including incidental kills, illegal shooting, 

 changes in prey availability and biomass, and 

 perhaps other unidentified factors. 



The U.S. population of California sea lions 

 (Zaiophiis caUfomiamis) is increasing at a rate 

 of about 10% annually. In 1990. NMFS esti- 

 mated that the U.S. population was 111,000 

 individuals (Table 2). A number of human-relat- 

 ed interactions, such as incidental take during 

 fishing, entanglement, illegal killing, and pollu- 

 tants, result in sea lion deaths. 



Reference 



NOAA. 1994. Our living ocean: report on the status of U.S. 

 living marine resources. 1993. NOAA Tech. 

 Memorandum NMFS-F/SPO-15. National Oceanic and 

 Atmospheric Administration, National Marine Fisheries 

 Service, Silver Spring. MD. 136 pp. 



