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THE SLEEPING HABITS OF WHALES. 
R. W. GRAY. 
Whales are able to exist without breathing for many minutes 
and, perhaps, for hours at a time. But for this gift they 
would often be unable to satisfy their hunger and obtain the 
repose they from time to time require. Their lungs must be 
very powerful ; large whales sometimes project their breath 
high into the air, at the same time making a noise that may 
be heard a mile or more away. 
In 1885, and again in 1889, I had the good fortune to see a 
Greenland whale asleep ; on both occasions the whales were 
seen among the drifting ice off the Greenland coast, and both 
of them were caught. 1 
A Greenland whale asleep presents a remarkable sight ; 
it is absolutely motionless and gives no signs of life. How 
long the animal is able to remain in this condition without 
awakening to breathe is a question I am unable to answer. 
The attitude assumed by the sleeping whale probably 
depends on the position of its centre of gravity and that of its 
centre of buoyancy ; when the former is far forward the head 
must sink down ; when it is farther back the contrary will 
take place. In the two instances referred to, the back was 
awash and only the ‘ crown ’ (on which the blow-holes are 
situated) exposed ; but according to my father, the late 
Captain David Gray, of Peterhead, they sometimes fall asleep 
with the head under water and only the hinder part of the 
body exposed. 2 
I now propose to ask and to answer, so far as is possible, 
certain question that arise in connection with the sleep of 
whales. Firstly, where do they usually sleep, at or below the 
surface ? In my opinion the answer is in accordance with the 
latter alternative, that is to say, they usually sleep under water 
below the level of the wave motion and, in Arctic and Antartic 
seas, of the drifting ice, where they are hidden from human 
observation and where they cannot be molested by birds. 
The following are my reasons : — 
(1) Whales are seldom seen sleeping at the surface. The 
celebrated Scoresby, speaking of the Greenland whale, says, 
Whales are seldom found sleeping, yet instances occasionally 
occur in calm weather among the ice/ 3 My father, speaking of 
the feeding habits of the same species says, £ Sometimes, if the 
weather is fine and the sun warm, they will fall asleep on the 
surface of the water near where they have been feeding and will 
1 See my ‘ Sleep of Whales/ Nature, April 30th, 1927, and my 
Peterhead Sealers and Whalers ' now appearing in the Scottish N aturalist . 
2 Scottish Fishery Board’s Seventh Annual Report, Part 3, p. 367. 
3 Arctic Regions, Vol. 1, p. 469. 
1933 Nov. 1 
