Chapter IV — Marine Mammal-Fisheries Interactions 
Table 9. 
observer coverage, 1988-1992' 
1988 1989 
Dolphin Mortality 
Des. 19,712 12,643 
Foreign 59,215 84,336 
Total 78,927 96,979 
Kills per Set 
US. 5.28 3.60 
Foreign 10.87 10.87 
Combined 5.34 3.69 
Sets on Dolphins 
US. 3,766 3,435 
Foreign 6,749 9,145 
Total 10,515 12,580 
Observer Coverage’ 
U.S. 53.2% 99.0% 
Foreign 35.3% 35.5% 
Combined 40.4% 48.2% 
Estimated U.S. and foreign dolphin mortality, kills per set, sets on dolphins, and percent 
1990 1991 1992’ 
5,083 1,002 439 
47,448 26,290 <20,000 
52,531 27,292  < 20,500 
2.75 2.49 0.58 
6.35 2.90 1.78 
2.81 2.87 = 
1,845 430 582 
8,770 9,052 _ 9,500-11,000 
10,615 9,482 =. 
100.0% 100.0% 100.0%* 
40.1% 56.4% = 
48.8% 59.7% > 65.2%5 
1 Data provided by the National Marine Fisheries Service and the Inter-American Tropical Tuna Commission. 
2 Figures for 1992 for the foreign fleet are preliminary estimates provided by the Inter-American Tropical Tuna Commission. 
3 Observer coverages are given for the percentage of trips observed. 
4 Includes observers placed under the United States and the Inter-American Tropical Tuna Commission observer programs. 
5 The estimate of total observer coverage for 1992 does not include observers placed under the national programs of Mexico or the 
United States. 
Based on preliminary data, it appears that the 1992 
incidental mortality rate for the foreign fleet, as well 
as for the U.S. fleet, was the lowest since the fishery 
began. Since 1989 dolphin mortality incidental to the 
eastern tropical Pacific tuna fishery has been reduced 
by almost 80 percent. 
As discussed below, the National Marine Fisheries 
Service published a final rule on 8 October 1991 
changing the period used to make foreign comparabili- 
ty findings from a calendar year to a fishing year, 
running from 1 October to 30 September. For fishing 
year 1991, the U.S. fleet had an incidental mortality 
rate of 1.89 dolphins per set. The mortality rate of 
the U.S. fleet for fishing year 1992, against which 
1992 comparability determinations for foreign fleets 
will be made, was 1.04 dolphins per set. 
Vanuatu is the only nation whose tuna fleet made 
sets on dolphins during 1992 that has provided the 
United States with the data necessary to make a 
comparability finding. Those data indicate that 
Vanuatu’s program will again be found comparable to 
that of the United States. Vanuatu achieved a kill rate 
of 0.8 dolphins per set, with eastern spinner and 
coastal spotted dolphins accounting, respectively, for 
6.2 and 0.6 percent of the total mortality. 
Implementation of the 1988 Amendments 
In 1988 changes were enacted in the legislative 
program governing the take of marine mammals by 
the U.S. tuna fishery and the importation of yellowfin 
tuna taken by foreign fleets. These amendments and 
steps taken to implement them during 1992 are 
summarized below. 
