Translation 2783

. • 25D
penetrate even into the Gulfs of bothnia and einland.
They nave also
been observed off the coasts of the Netherlands, Denmark, and Great
britain. In nay and June 1966 a white whale entered trie river Lhine
and ascended 400 km above its mouth.
The white whale is able to winter in the ice-ïields, finding
small patches of open water.
to 2.5 cm thick, with its back.
It breaks easily througn thin ice,• up
White whales make migrations in various directionsf depending
on the area in which they live. In the Kara Sea, for instance,, they
appear in APril and May and stay all summer, but a large proportion
of them go away west for the winter, into the Barents,s -ea; a certain
number spend the winter in catches of open water in the Gulf of Ob'.
The principal items' in the diet of wnite whales are shoal
fishes: in the White Sea, herring and capelin, in the Kara Sea, Arctic
cod;•and in Greenland waters, cod and ocean perch.
They often eat
demersal fishes such as halibut,•flounder, etc., and . also various
invertebrates.
The period during which they attain sexual maturity is very
prolonged. The females mature when they reach a length of 515 cm or -
more, at the age of three years and upward. iexually-immatura specimens
. three or four years old have been observed.
The - mating season extends over about half the year, - from the
end of February to the end of August, with a peak
the second half
of April and early May. Gestation lasts for about' s'. year, and the
young are born mostly in spring, with a second peak at the end of
summer. Births have been observed in September and even in 1,ovember.
As a rule a single calf is produced. Lew-born, calves.are usually
about 150 cm in length.
The lactation period apparently lasts for about half a year.
The.milk has a fat content of up to 27, sometimes as much as 33.
• Cases are known of embryos being found in females that were
still lactating. Therefore L:ome of tne females talw part in repro- .
duction.every year; others produce youn twoe in v,hreu year:.;, end
sometimes,oven less often.
sonietirum SOCh.
When a white whale aPpears on tne surface a slaall 'Jpout ln
he animalo are ureu.arioun and ,,enorally rowain in •
groups, uometines conre;ating in herds of hundreds or even thousands.