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PACIFIC SCIENCE, Vol. XIII, July 1959 
away in the shallows. As weaning approaches, 
mother and pup spend more time in the 
water and may go 100-200 yards from the 
beach. 
Recognition of Pups by Mothers 
When mother and pup are disturbed by 
humans, or when they are crawling along the 
beach, they keep in contact by a continuous 
series of calls, the mother bellowing and the 
pup bleating. When a pup is out of sight of 
its mother, she locates it by its bleating and 
crawls in the direction of the sound. 
On May 4, when pups MS-12 and MS-13 
were 33 days old and after MS- 12 had been 
deserted by its mother, both pups were taken 
to a common location for weighing. As usual, 
the mother of MS- 13 followed. After weigh- 
ing MS- 12, we released it on the beach, and 
then carried MS- 13 behind a dune out of 
sight of its mother, so that she would not 
interfere with the weighing. When the mother 
of MS- 13 noticed her pup was gone, she 
looked about and immediately noticed pup 
MS- 12, which was bleating. She crawled rap- 
idly to it, sniffed it several times, then turned 
away and continued her search for her own 
pup, indicating that a mother recognizes her 
pup by smell. 
A few minutes later pup MS- 12 approached 
MS-13’s mother and tried to nurse. She did 
not at first object. However, when her own 
pup was returned, she became confused and 
very excited. She lunged at and bit both pups. 
A brief interval of bleating, bellowing turmoil 
followed. The mother bit both pups several 
more times and grasping them in her teeth 
she attempted to toss them both away from 
her. Pup MS- 12 soon became discouraged 
and hastened to leave. Pup MS- 13 continued 
to approach his mother’s face, but still con- 
fused, she bit at him and he angrily bit back 
at her. The mother then proceeded toward the 
water, her pup following. Exhausted by the 
exertion, she soon stopped, and when her 
pup approached bleating, she nuzzled and 
accepted it. Within five minutes, she was 
nursing her pup and MS- 12 was not seen to 
approach her again. 
Care and Defense of Young 
The mother monk seal shows considerable 
affection toward her young. The pup often 
rubs and nuzzles its mother’s head and neck, 
and the mother sniffs and nuzzles her pup in 
an affectionate way. When a bleating, fright- 
ened pup is allowed to return to its mother, 
she usually places her head and neck over it 
protectively (Fig. 11), and the bleats of the 
pup are answered by deep moaning sounds 
from the mother. This behavior is in marked 
contrast to that of the Alaska fur seal mother 
which, other than to nurse it, shows little re- 
gard for her pup. Rarely, and only within a 
few hours after birth, a mother fur seal will 
remain near her pup or attempt to drag it 
with her when she is frightened and other 
animals are departing. 
From the time her pup is born until she de- 
serts it, the mother monk seal normally re- 
mains aggressive toward humans and other 
seals, except toward other nursing females 
with whom she is loosely associated. In order 
to tag and to obtain weights and measure- 
ments of pups, it was necessary for one of us 
to divert the mother while the other made off 
with the pup. 
On the day that pup MS- 13 was born, it 
was taken from its mother for tagging and 
weighing. While one of us diverted the 
mother, the other dragged the pup behind a 
sand dune. The mother, occupied with her 
tormentor, failed to miss her pup until it was 
beyond her range of vision. When she missed 
it she first dashed toward the water, looking 
frantically about. Seeing no sign of her pup 
there, she turned rapidly about in several, 
circles, constantly peering behind her and 
bellowing. Soon she heard the bleating of 
her pup and proceeded in the direction of the 
sound. This mother remained unusually ag- 
gressive in protecting her pup until shortly 
before deserting it at the end of the nearly 
6- week nursing period. 
