Waring et al.: Incidental take of marine mammals off northeast United States 



353 



Figure 3 



Distribution of incidental takes of pilot whales in foreign 

 fishing activities off the northeastern United States, 

 1977-88. 



Of the DWF fisheries mortality of pilot whales since 

 1984, 93% occurred in the Atlantic mackerel fishery 

 (Table 1). During 1984-87, the Netherlands and the 

 GDR caught 54 and 33 animals, respectively, which 

 combined represent 90% (n = 97) of the pilot whales 

 taken in the mackerel fishery during that 4-year period. 

 In 1988, Poland began commercial fishing for Atlan- 

 tic mackerel and caught 41% (n = 58) of the pilot whales 

 taken that year. Although the Netherlands did not fish 

 in the EEZ during 1986, they still caught 44% (104/239) 

 of the pilot whales taken since 1984 in the Atlantic 

 mackerel fishery. 



Summary of kill rates by fishery and country 



Loligo fishery The total number of marine mammals 

 (all species) killed per days fished (k/d rate) by Italy in 

 the directed Loligo fishery was more than six times that 

 of either Japan or Spain between 1984 and 1986 (period 

 of nearly 100% observer coverage) (Table 2). During 

 the years 1985 and 1986, this rate was approximately 

 10 times greater than the same rate for Spain, in spite 

 of comparable number of days fished (Table 2). The k/d 

 rates for 1984-86 between the three countries, how- 

 ever, are not significantly different using the Fried- 

 man test (P<0.19). 



Atlantic macl<erel fishery The k/d rate in the Atlan- 

 tic mackerel fishery has varied both over years and 



among countries (Table 3). Between 1984 and 1988, the 

 average kill rate for the GDR and the Netherlands was 

 0.12 k/d. The Netherlands annual k/d rates were 4 to 

 17 times greater than GDR rates, and differences in 

 the k/d rates between these two countries are signifi- 

 cant, P<0.06. With the inclusion of the 1988 takes by 

 Poland, the all-years (pooled) k/d rate increases to 0.14 

 (Table 3). The 1988 k/d rates for each country were the 

 highest observed during the 5-year period, 1984-88 

 (Table 3). 



Summary of incidental take by fishery 

 and time of day 



Loligo fishery The incidental take of common dol- 

 phins during daylight hours (0800-1600) was signifi- 

 cantly less (x^ = 44.48, 2 df, P< 0.001) than the num- 

 ber captured during dawn/dusk or the night (Table 

 4). The number of pilot whales captured in the Loligo 

 fishery did differ significantly by time period (x^ = 

 1.02, 2 df) (Table 4). 



Atlantic mackerel fishery Similar to the Loligo fish- 

 ery, the number of common dolphins captured during 

 daytime hours was significantly less (x^ = 20.42, 2 df, 

 P< 0.001) than the number caught in tows at other time 

 periods throughout the day (Table 5). The number of 

 pilot whales caught in tows conducted during the night 

 (2000-0400) was significantly less (x" = 8.28, 2 df. 



