Chapter III — Species of Special Concern 
individually recognizable whales were missing from 
the pod in 1990. If the missing whales are dead, the 
mortality rates for the pod were 19.4 percent in 1988- 
1989 and 20.7 percent in 1990-1991. The average 
annual mortality rate in the same pod from 1984 to 
1988 was 6.1 percent. Several of the missing whales 
were females that left behind offspring subsequently 
seen with the pod. There are no previous records of 
female killer whales abandoning their offspring. 
Evidence suggests that loss of the females altered the 
social structure of the pod, and significant mixing of 
maternal groups has occurred. An additional whale 
was missing in 1991, but a calf was also born into the 
pod. In 1992 no whales were missing from the pod 
and two births occurred. 
On 25 September 1991 the Federal Government 
and the State of Alaska agreed to a settlement for 
injuries resulting from the rupture of the Exxon 
Valdez. A Trustee Council, comprised of the Federal 
Trustees’ designees and the State Trustees, was 
established; the Council is responsible for decisions 
relating to the assessment of injuries, uses of the 
funds received for restoration, and all restoration 
activities. Studies of Prince William Sound killer 
whales have been part of the damage assessment and 
restoration program, and the research is expected to 
continue in 1993. 
Commission Review of 
Population Assessment Proposals 
On 23 October 1992 the National Marine Fisheries 
Service asked the Commission to review a number of 
proposals submitted by its regional fisheries science 
centers. The proposals were for continued support of 
studies being done to assess the status of marine 
mammal populations possibly being affected adversely 
by interaction with various fisheries in U.S. waters. 
The studies are intended to obtain information neces- 
sary to implement the Service’s proposed regime to 
govern interactions between marine mammals and 
commercial fishing operations (see Chapter IV). 
One of the proposals was for continuing a three- 
year survey to obtain a minimum estimate of killer 
whale abundance in Alaska coastal waters. The 
proposal noted reports of fishermen using high-pow- 
67 
ered explosives to frighten killer whales away from 
their boats during fishing operations and recent 
evidence of bullet wounds in killer whales (some 
individuals in 42 percent of the pods studied reported- 
ly exhibited bullet wounds). It indicated that without 
a minimum population estimate, fisheries in Alaska 
would be in jeopardy of being closed due to the 
potential for interactions with killer whales. 
The Commission transmitted its comments to the 
Service on 3 December 1992, noting that killer whales 
are being taken intentionally, not incidentally, in 
certain Alaska fisheries. Such intentional taking is 
prohibited under the present interim exemption and 
would be prohibited by the Service’s recommended 
fegime to govern marine mammal-fisheries interac- 
tions after 30 September 1993. Consequently, the 
Commission pointed out that the problem described in 
the proposal appears to be an enforcement problem 
that cannot be resolved by obtaining a minimum 
population estimate. The Commission also noted that, 
if a minimum population estimate is needed, it is not 
clear that it could be obtained most economically by 
the proposed study design for planned boat surveys. 
Much of the available data concerning the distribu- 
tion and abundance of killer whales in Alaska waters 
have come from the comprehensive surveys and 
photo-identification studies that were done in Prince 
William Sound and adjacent areas as part of the Exxon 
Valdez oil spill damage assessment program noted 
earlier. Also, several independent groups of investi- 
gators have been conducting killer whale studies in 
different parts of Alaska and are providing the Nation- 
al Marine Mammal Laboratory copies of identification 
photographs of individual killer whales taken during 
those studies. The Commission noted that the Nation- 
al Marine Mammal Laboratory’s proposal did not 
reference or describe these studies, nor indicate why 
the Laboratory could not provide any distribution or 
abundance estimates based on data already collected. 
The Commission recommended that, if funding is 
available for studies of killer whales in Alaska, 
priority be afforded to evaluating possible means for 
preventing or reducing killer whale predation of fish 
being caught in longline fisheries and that consid- 
eration be given to expanding the ongoing photo- 
identification studies being conducted by other inde- 
pendent researchers. 
