390 
Fishery Bulletin 107(3) 
20 
red hake 
15 : 
/i=134 (summer=23, 
winter=1 11) 
10 - 
5 : 
0 - 
| 
lu*. 
Ml _ 
1.1.-, 
.. illil litiLii i, 
1 J . . 1 . _ 
V # # tff <§f $r 
Length (mm) 
Figure 2 
Length-frequency distributions for fishes eaten by Atlantic white-sided dolphins 
( Lagenorhynchus acutus ) in the Gulf of Maine (1991-2006). (A) Red hake (Uro- 
phycis chuss) all seasons; (B) haddock (Melanogrammus aeglefinus ) all seasons; 
(C) silver hake ( Merluccius bilinearis ) winter; (D) silver hake summer; (E) 
Atlantic herring (Clupea harengus) all seasons. 
frequency diagrams shown in Figure 2 for the most 
abundant species. 
Results and discussion 
Stomachs of immature and adult dolphins of both 
sexes were examined. The two calves were 119 cm 
and 139 cm in length and had milk but no solid prey 
in their stomachs. The smallest juvenile was 161 cm 
and contained solid prey but no milk in its stomach. 
Females longer than 200 cm and males longer than 
230 cm were considered mature (Sergeant et al., 1980) 
(Table 1). 
Altogether, the 62 L. acutus stomachs contained 5561 
fishes of at least 26 species, and 304 cephalopods of one 
octopus and two squid species (Table 2). Most of the 
stomach contents were trace remains. The most com- 
monly found prey species, in order of abundance, were; 
1) Madeira lanternfish ( Ceratoscopelus maderensis), 
3876 individuals, all but one from a single stomach; 
2) silver hake (Merluccius bilinearis), 945 individuals 
from 22 stomachs; 3) sand lance ( Ammodytes spp.), 
271 individuals from a single stranded dolphin; 4) 
spoonarm octopus ( Bathypolypus bairdii), 212 indi- 
viduals from 14 stomachs; 5) haddock (Melanogrammus 
aeglefinus ), 107 individuals from eight stomachs; 6) 
Atlantic hagfish (Myxine glutinosa ), 105 individuals 
