same time, the risk of oil spills in and near the population's 

 range was increasing as a result of increased tanker traffic, due 

 primarily to transport of oil from the recently completed Alaska 

 pipeline. 



Because of its small size and limited distribution, and the 

 increasing risk of oil spills and other catastrophic events, the 

 California sea otter population was designated as threatened 

 under the Endangered Species Act in January 1977. The most 

 effective way to insure that the population would not be 

 threatened by oil spills would be to establish one or more sea 

 otter colonies outside the existing population's range in 

 California. However, such an action could adversely affect 

 commercial and recreational fisheries for abalone, clams, and 

 other invertebrates eaten by sea otters. It also could reduce 

 populations of sea urchins and other species that consume kelp, 

 and thus benefit the kelp industry and both recreational and 

 commercial fisheries for finfish that inhabit kelp beds. 



The Marine Mammal Commission recognized the need to consider 

 and to minimize possible adverse effects on commercial and 

 recreational fisheries, as well as to protect the California sea 

 otter population. Accordingly, in December 198 0, it recommended 

 that the Fish and Wildlife Service adopt and implement a 

 management strategy recognizing the ultimate need for "zonal" 

 management of sea otters and the need to establish one or more 

 sea otter colonies at a site or sites not likely to be affected 

 by an oil spill in or near the population's current range. The 

 Fish and Wildlife Service concurred with the Commission's recom- 

 mendation and incorporated the zonal management concept into the 

 Southern Sea Otter Recovery Plan adopted in February 1982. 



Past Commission efforts to help with development and 

 implementation of an effective Southern Sea Otter Recovery Plan 

 are described in previous Annual Reports. Brief summaries of 

 some of these efforts and descriptions of actions taken in 1989 

 are provided below. 



Incidental Take 



When the California sea otter population was listed as 

 threatened in January 1977, it was assumed that the population 

 was increasing and would continue to increase at about five 

 percent per year for the foreseeable future. However, as noted 

 in previous Commission reports, subseguent studies indicated that 

 substantial numbers of sea otters were being caught and killed 

 incidentally in coastal gill and trammel net fisheries and that 

 this incidental take may have been sufficient to stop and reverse 

 the population increase. Thousands of seabirds and non-target 

 fish species, as well as sea otters and other marine mammals, 

 also were being caught and killed in gill and trammel net 

 fisheries along the central California coast. 



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