Translation 2783

..... 269:.,
The distribution of sperm whales in summer depends chiefly
I
on that of the principal items in their diet, cephalopods.
Concentrations of sperm trha.les are generally restri.cted to
parts of the sea where the depth increases abruptly and where cyclonic
currents arise, favou-rin^, the transportation of the biogenic
elements required for the development of their food base, and also
to the zone of descenc:.in- water currents (zone of convergence).
The females, which are considerably smaller than the males,
feed mainly in the upper water layers, consuming principally warmthloving
forms of cephalopods. The males are capable of diving to
t^;rea,t
depths (300-400 metres or more), and. cold-loving deep-water
forms predominate in their diet.
In the Bering Sea, the Gulf of. Alaska, and Aleutian waters,
sperm whale stomachs have been found to contain remains of 16 spe--
cies of squids, two species of octopuses, and five species of fishes.
In the Loti•rer.. Ca.li:eornia region sperm whales feed mainly on the squids
Iloroteuthis and CTonatonsis, and less often on rays, A'ebbl°es wei^hin•^
from 10--20 g u7r to 1,, 4.00 g are quite often z"ouricï_ in their stomachs.
During the fattening -oeriod sperm whales remain in groups.,
which often consist of animals of a>articular size or age. When
tI,_e
lengths of the ar_izials in agrou}^ are from 1-1.6 to 13 metres
their ages are approximately the same, but in groups consisting of
larger animals there are individuals of various ages. In the Gulf
of Alaska region st erm whales measuring up to 13.0 metres -predominate
in the groups during Aï)ri1 and May, but in June and especially in
July the Erou-ns consist mostly of larger animals.
The females attain sexual maturity at a body length of about
8.5--8.8 metres; the males become sexually mature when their body
length is S?.5 metres and the weight of their testes is 1 kg or more.
Gestation lasts about 16.5 months. 'Hating usually takes place from
February to June, and parturition from June to October, with a peak
in All^^ust.
The new-born calves are about 4.05 i;ietres long (accordinf;
to other data, un to 4.27
meures). They feed on their mothers'
milk, which has a fat content of 36-3&D, for from five or six months
u^) to ^'. or. 25 months k ';'he .fe:^ia._les mate once in three or four years;
those to.•^in.^; ,^^.rt in rel^lo^-uc^Li.on fo,: '--o first time mate 1.5 months
later, on cn a.vera.,-;e, t_-ian t's-.ose that have proù.uced youiz`;.