Acta Zoologica Cracoviensia, 26 (1982 - 1983)
Body proportions in adults and fledgelings of the Little Auk
Abstract:
The comparative analysis carried out in this work included the external dimensions of the body, the area and shape of the wings and paddles, the size of the skull, breastbone, shoulder girdle and limbs, and the weight of certain muscles and the heart of adult Little Auks and their fledgelings at the time of their flying out of the breeding colony. It appeared that the body proportions of juveniles are theoretically more advantageous than those of the adults so far as their fitness for flight is concerned. The wings of 26-day-old Little Auks are less loaded, have a more advantageous shape and a larger relative area. The size of the bones of their shoulder girdle and limbs resembles their final dimensions. The relative weight of the pectoral muscles is similar to that of the adults. The relative weight of the heart of the fledgelings is nearly one and a half times as large as that of the adult birds. The body proportions which young Little Auks reach at the time of their departure from the colony result to a great extent from the pre-fledging loss of weight.
