Translation 2783

(Phe Mating period is prolonged, and generally lasts from
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the end of December to the middle of.February,..with a possible peak
in the second half of January. Both mating'and the birth of young
take place in the shallow bays of the small islands south of South
Korea (Asiatic herd) and in the numerous lagoons in the Gulf of .
California (American herd). The females breed once in two years,
and sometimes every year.
Gestation lasts for almost a year (according to recent data,
for 13 months). Eew-born calves are 3.7-5.5 metres long, averaging
4.7-4.8.metres. During the lactation period, which lasts for about
six or seven months, the calves attain a length of about 8.5 metres.
The milk is very rich, with a fat content of about 50-55%.
Grey whales are.usually (40%) seen in pairs.
The spout, if
seen from in front or behind, consists of two jets, but the jets are
closer together than those of right whales. The spout is usually
not high, about 2-3 metres, and rarely as much as 4 metres. .
• The maximum rate of movement of grey whales is 14-16 knots,
but ordinarily they move at 3 or 4 knots.
A distinctive feature of these whales is their close adherence
to the coasts, near which they keep praCtically throughout
their lives.
Before a prolonged dive grey whales usually display their
flukes in the air, and they go down almost vertically. Their return
to the surface may take different forms. Sometimes only the head
shows above the surface; it is supposed that in that way the whales
can look around and even orient themselves in their movement. They
are rarely seen to leap out of the water.
A grey whale 5 metres in length and weighing about 1.5 tons
has been kept in an oceanarium.
one-and-a-half months.
It died from an infection after
Grey whales, more than any other whale species, are subject
to infestation by a number of skin parasites, chiefly whale lice,
and are also overgrown with.barnacles possessing large (up to 5 cm
in diameter) limy shells.
The barnacles usually settle on the head,
but they are also found on the flippers and the flukes.
Grey whales' internal parasites have not been well studied,
only helminths (cestodes) having been recorded.