Chapter IV 
MARINE MAMMAL-FISHERIES INTERACTIONS 
Marine mammals may interact with fisheries in a 
number of ways. They may be disturbed, harassed, 
injured, or killed either accidentally or deliberately 
during fishing operations; they may take or damage 
bait and fish caught on lines, in traps, and in nets; 
they may damage or destroy fishing gear or injure 
fishermen while trying to remove bait or caught fish 
or when they accidentally become entangled in fishing 
gear; and they may compete with commercial and 
recreational fishermen for the same fish and shellfish 
resources. 
The Marine Mammal Protection Act directs the 
Secretaries of Commerce and the Interior, in consulta- 
tion with the Marine Mammal Commission, to devel- 
op regulations governing the incidental taking of 
marine mammals by persons subject to the jurisdiction 
of the United States. In 1988 the Marine Mammal 
Protection Act was amended to establish a five-year 
interim exemption to govern the taking of marine 
mammals incidental to commercial fisheries other than 
the eastern tropical Pacific tuna fishery. The interim 
exemption was designed to allow commercial fisheries 
to operate while information is collected on the extent 
and effects of marine mammal-fisheries interactions. 
With respect to the eastern tropical Pacific tuna 
fishery, incidental taking of marine mammals contin- 
ues to be regulated under a general permit issued in 
1980 to the American Tunaboat Association. That 
permit, however, will expire on 1 March 1994 if any 
major tuna fishing nation formally commits to a global 
moratorium on the practice of catching tuna by setting 
on marine mammals. If no major tuna fishing nation 
commits to the moratorium, the general permit will 
expire on 31 December 1999. 
The 1988 Marine Mammal Protection Act amend- 
ments also direct the Secretary of Commerce, based 
upon recommended guidelines provided by the Marine 
Mammal Commission, to submit to Congress a 
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suggested new regime to govern incidental taking of 
marine mammals in fisheries other than the tuna purse 
seine fishery after the interim exemption expires on 1 
October 1993. 
Actions taken in 1992 to address these matters are 
discussed below. Also discussed are recent efforts to 
assess possible changes in the structure of the Bering 
Sea and Gulf of Alaska ecosystems. Fishery interac- 
tions affecting Hawaiian monk seals, Steller sea lions, 
killer whales, vaquitas, and sea otters are discussed in 
Chapter III. Activities concerning high seas driftnet 
fisheries, which pose serious threats to marine mam- 
mals and many other marine species, have been 
subject to international negotiations and are discussed 
in Chapter V. 
Interim Exemption 
for Commercial Fisheries 
Subject to certain exceptions, the Marine Mammal 
Protection Act established a moratorium on the taking 
and importing of marine mammals. Recognizing that 
a total prohibition of taking could seriously affect 
certain fisheries, the Act, as passed in 1972, autho- 
rized the Secretaries of Commerce and the Interior to 
issue general permits through formal rulemaking to 
allow the taking of marine mammals incidental to 
commercial fishing operations when such taking 
would not disadvantage the affected marine mammal 
species or stocks. The Act was amended in 1981 to 
streamline procedures for authorizing the accidental, 
but not intentional, taking of small numbers of non-- 
depleted marine mammal species and stocks during 
commercial fishing operations if, after notice and 
opportunity for public comment, the Secretary finds 
that the total of such taking would have a negligible 
impact on the affected species or stocks. 
