MARINE MAMMAL COMMISSION — Annual Report for 1992 
of taking; (2) measures that might be taken to 
reduce unnecessary taking and to allocate the 
allowable take equitably among foreign and U.S. 
fisheries and other users; and (3) the likelihood 
that ongoing or planned monitoring programs are 
adequate to ensure that the affected populations are 
increasing toward, or being maintained within, 
their optimum sustainable population ranges; 
¢ the proposal be expanded to describe the program 
that would be undertaken to reduce marine mam- 
mal mortalities and injuries incidental to commer- 
cial fishing operations to as near zero as practica- 
ble; and 
e the Service provide, as part of the proposal and 
Legislative Environmental Impact Statement, draft 
legislative language illustrating how the proposed 
regime might be translated into law and an estimate 
of the cost to implement the proposed regime. 
The National Marine Fisheries Service’s 
Revised Draft Regime 
The National Marine Fisheries Service received a 
large number of comments on its initial draft regime. 
While comments were received on all aspects of the 
proposal, many commenters focused on two points, 
the complexity of the Service’s proposal and its broad 
applicability. Several commenters believed that 
attention should be focused primarily on those fisher- 
ies with significant marine mammal incidental take 
problems. The Service considered the comments and, 
on 20 November 1991, made a revised draft regime 
available for public review. 
In the revised draft, the Service replaced the term 
“allowable biological removal” with “potential biolog- 
ical removal” to clarify that it represented the total 
number of individuals that could potentially be re- 
moved from a population, not necessarily the number 
of removals that would be authorized. The Service 
also revised the recovery factors to be used in calcu- 
lating potential biological removal levels in response 
to claims that the original recovery factors were 
unnecessarily conservative. The recovery factor for 
severely depleted stocks (those below one-third of 
carrying capacity) and those of unknown status was 
94 
revised upward from 0.1 to 0.5 (in effect increasing 
the take that potentially could be allowed by 500 
percent), and the factor for stocks between one-third 
and two-thirds of carrying capacity was revised from 
0.5 to 0.75. Under the revised proposal, no recovery 
factor would be used for stocks determined to be 
above two-thirds of carrying capacity. 
With respect to carrying capacity, the revised draft 
regime appeared to indicate that current, rather than 
historical, carrying capacity would be used as the 
upper limit of the optimum sustainable population 
range. The lower limit of the optimum sustainable 
population range, the maximum net productivity level, 
is proportional to the carrying capacity level. Thus, 
if carrying capacity has been reduced by overfishing, 
environmental pollution, or other forms of habitat 
degradation or destruction, an affected marine mam- 
mal stock could be reduced but still be judged not to 
be depleted until it is listed as endangered or threat- 
ened under the Endangered Species Act. 
The Service also proposed a new and somewhat 
more complex method for classifying fisheries. 
Historical data would be used to determine which 
commercial fisheries interact with marine mammals 
and which do not. All vessels operating in fisheries 
identified as interacting with marine mammals would 
be required to register with the Service. Those 
fisheries would be further classified based on the 
status of the marine mammals taken and the total level 
of takes from all sources relative to the calculated 
potential biological removal. Class A fisheries would 
be those that interact with endangered, threatened, or 
depleted marine mammals or with marine mammal 
stocks with an estimated annual removal level (from 
all sources) which equals or exceeds the potential 
biological removal level. Class B would include those 
fisheries that do not interact with depleted marine 
mammals but that interact with stocks whose potential 
biological removal level, although not now exceeded 
by total annual removals, is expected to be exceeded 
within the next three to five years. Class C fisheries 
would be those that do not interact with marine 
mammals from depleted stocks or from stocks whose 
potential biological removal level is likely to be 
exceeded within the next five years. 
