. Bulletin. Science; Natural history; Natural history. RESEARCH NOTES 195. '&? r^' Fig. 3. Position during final stages of birth with calf maintained above surface of water. the nearly black female. The calf swam quite well as the pair moved purposefully away from us. An unsuccessful search was made for any placental material. No attempt was made to follow the pair which had slowed and was milling around. The female exhibited a high tolerance to our continued noisy presence. In what must have been trying circumstances for her, not once did she display any hint of aggressive recognition of
. Bulletin. Science; Natural history; Natural history. RESEARCH NOTES 195. '&? r^' Fig. 3. Position during final stages of birth with calf maintained above surface of water. the nearly black female. The calf swam quite well as the pair moved purposefully away from us. An unsuccessful search was made for any placental material. No attempt was made to follow the pair which had slowed and was milling around. The female exhibited a high tolerance to our continued noisy presence. In what must have been trying circumstances for her, not once did she display any hint of aggressive recognition of our presence. Two other females with calves passed within 50 m during this female's parturition with no indication or inclination to "assist" with the birth. Gilmore (1961) noted the likelihood of the tail-first underwater delivery but told us of a verbal report of a cephalic birth at Laguna San Ignacio in very shallow water during the week preceding Easter, 1976 (per. comm.) While the birth of the whale reported by Leatherwood apparently took place below the surface and out of sight, the remaining three reports in the literature of the gray whale are of cephalic births at the surface. The possibility remains that all reported cephalic births including Lindsay (1978) are abnormal births; that gray whales, and perhaps by extension, baleen whales, normally deliver their young by breech, or tail-first presentation, just below the surface. This is the case with Tursiops and other genera of smaller odontocetes whose births have been observed in various marine aquaria, a ma- jority of which has been of tail-first births. Additional support for tail-first births has been obtained from the whaling in- dustry. Slijper (1962) cites records of female baleen whales of several species taken during pregnancy, particularly advanced pregnancy, in which the great majority of fetuses was found with the caudal section oriented toward the cervix. Additionally, Rice and Wolman (1971) repo
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