Корпус как несущая плоскость и плавучесть некоторых ластоногих (Pinnipedia)

Abstract

The specific weight and correspondingly the flotation of the majority of the Pinnipedia representatives change considerably with an age and at different seasons. However during a long period of a year the specific weight of these animals is less than a unit owing to corresponding adaptation directed to its decrease. In October—November, 1967, the specific weight was determined of 21 slaughtered Pusa caspica Gmel. of different age, sex and fatness, and in April, 1967,— of one alive Pusa caspica in the aquarium of the Georgian research fishery station (Batumi). It was established that the specific weight varies within the limits of 0.886—0.992. The form of the Pusa caspica and Pagophoca groenlandica E r x l. body is considered in connection with their flotation. As the dorsal profile of the body of these animals is somewhat more convex than the ventral one, their bodies when moving in the direction of their longitudinal axis perform the function of a carrying plane.