caa a22 4500 465763693 CHVBK 20180323111907.0 cr unu---uuuuu 170327e19900201xx s 000 0 eng 10.1007/BF00238429 doi (NATIONALLICENCE)springer-10.1007/BF00238429 Breeding biology of weddell seals ( Leptonychotes weddellii ) at Drescher Inlet, riiser larsen ice shelf, Antarctica [Elektronische Daten] [Peter Reijnders, J. Plötz, J. Zegers, M. Gräfe] Summary: The breeding biology of Weddell seals (Leptonychotes weddellii) was studied at Drescher Inlet (Antarctica) during the austral late winter and spring 1986. The whelping season was estimated to last about 40 days, with a peak in pupping at late October. No post natal mortality was observed during the whole study. The attachment between parous females and their pups was strong during the first five weeks after parturition. From the third week on mothers spent more time in the water than the pups. Data on daily peak haul-out time of pups, post natal presence of pups on the ice and distribution of births during the whelping season, indicate that censuses should be carried out between 12.00 hours and 16.00 hours local time and during three weeks after the peak of the pupping season. Pups weaned between 6 and 7 weeks of age. Hormone concentrations (oestradiol-17β and progesterone) indicated that females did not come into oestrus during lactation. Throughout the whole lactation period the mother dominates the relationship with her pup. Growth of the pups was linear during the first 5 weeks post partum, during which period birth weight (x=29.1kg) increased more than 3 1/2 times. Until the 6th week of age the pups gained on average 2.6 kg/day, the respective weight loss in cows was 5.8 kg/day. The latter represents an average loss of nearly 38% of the initial weight at parturition. During the course of lactation, suckling frequency decreased, whereas the length of each bout increased resulting in an approximately constant total suckling duration per week. Of the energy used by females during the first 5 weeks, 52% was consumed by pups. Pups only took milk and the cows did not feed at all during the whole period of observation. Therefore the realized growth in pups, 10 g/min of suckling, was totally derived from energy stored by the cows. Springer-Verlag, 1990 Reijnders Peter Department of Estuarine Ecology, Research Institute for Nature Management (RIN), P.O. Box 59, NL-1790 AB, Den Burg, The Netherlands aut Plötz J. Alfred Wegener Institut für Polar-und Meeresforschung Columbusstrasse, D-2850, Bremerhaven, Federal Republic of Germany aut Zegers J. Department of Estuarine Ecology, Research Institute for Nature Management (RIN), P.O. Box 59, NL-1790 AB, Den Burg, The Netherlands aut Gräfe M. Alfred Wegener Institut für Polar-und Meeresforschung Columbusstrasse, D-2850, Bremerhaven, Federal Republic of Germany aut Polar Biology Springer-Verlag 10/4(1990-02-01), 301-306 0722-4060 10:4<301 1990 10 300 https://doi.org/10.1007/BF00238429 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00238429 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Reijnders Peter Department of Estuarine Ecology, Research Institute for Nature Management (RIN), P.O. Box 59, NL-1790 AB, Den Burg, The Netherlands aut NATIONALLICENCE 700 1- Plötz J. Alfred Wegener Institut für Polar-und Meeresforschung Columbusstrasse, D-2850, Bremerhaven, Federal Republic of Germany aut NATIONALLICENCE 700 1- Zegers J. Department of Estuarine Ecology, Research Institute for Nature Management (RIN), P.O. Box 59, NL-1790 AB, Den Burg, The Netherlands aut NATIONALLICENCE 700 1- Gräfe M. Alfred Wegener Institut für Polar-und Meeresforschung Columbusstrasse, D-2850, Bremerhaven, Federal Republic of Germany aut NATIONALLICENCE 773 0- Polar Biology Springer-Verlag 10/4(1990-02-01), 301-306 0722-4060 10:4<301 1990 10 300 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer