. REPRODUCTION, GROWTH AND AGE OF SOUTHERN FIN WHALES By R. M. Laws (Plates IV-VII and Text-figs. 1-60) GENERAL CONSIDERATIONS Introduction In his paper on the southern stocks of whalebone whales, Mackintosh (1942) summarized the work which had then been published and discussed some additional unpublished data. He remarked that' In recent years a good deal of new material relating to the breeding, growth, and age of whales has been collected by members of the Discovery Committee's staff and other biologists who have sailed in factory ships to the Antarctic. Work on this material, which include
. REPRODUCTION, GROWTH AND AGE OF SOUTHERN FIN WHALES By R. M. Laws (Plates IV-VII and Text-figs. 1-60) GENERAL CONSIDERATIONS Introduction In his paper on the southern stocks of whalebone whales, Mackintosh (1942) summarized the work which had then been published and discussed some additional unpublished data. He remarked that' In recent years a good deal of new material relating to the breeding, growth, and age of whales has been collected by members of the Discovery Committee's staff and other biologists who have sailed in factory ships to the Antarctic. Work on this material, which includes records of large numbers of ovaries, has been interrupted by the war, but it is hoped that it will be resumed in the future and much progress should be revealed when the results are available' (p. 216); and later (p. 226), 'The most important problem is to ascertain how many corpora lutea on the average are added each year in a sexually mature female'. Annual collections of ovaries were initiated, and have been continued, as a means of comparing the relative condition of the stocks of whales from year to year. A great deal of extra material has, therefore, accumulated since 1942 and continues to increase yearly. In a series of papers (Mackintosh and Wheeler, 1929; Wheeler, 1930; Wheeler, 1934; Peters, 1939; Mackintosh, 1942) attention was drawn to the use of counts of the corpora lutea and corpora albicantia in fin-whale ovaries as a measure of age. Ovarian scars have also been used for determining age in other groups of animals, for instance seals (Bertram, 1940; McLaren, 1958; Mansfield, 1958), the cow (Dawson, 1958), birds (Maynard, 1888; Wynne-Edwards, 1939), and even insects (Bertram and Samarawic- krema, 1958). Several estimates of the annual rate of accumulation of corpora albicantia in fin whales have been published ranging from 0-9 (Peters, 1939) to 2-5 (Wheeler, 1934), but they do not stand up to detailed criticism. When the present investigation began the main obje
Size: 2225px × 2247px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
