Perrin, W.F.; Würsig, B.; Thewissen, J.G.M. (2009). Encyclopedia of marine mammals. Second edition. Academic Press: London. ISBN 978-0-12-373553-9. xxix, 1316 pp. (look up in IMIS) [details]
At birth, mean standard length for pups is 67.4 cm (58-66). Males are born heavier at 5.9 kg (4.9-6.6) compared to females at 5.4 kg (4.8-5.9).