Killer whale (Orcinus orca) reproduction at Sea World

Abstract

Sea World has maintained killer whales (Orcinus orca) since 1965. The total killer whale inventory has included 39 whales (25 females, 14 males); 28 were wild-caught and 11 captive-born, including one second-generation calf. As of September, 1993, there were 19 whales in the breeding program. Ten of these whales (53%) were captive-born, either at Sea World or other facilities in North America. The live wild-caught whales ranged in estimated age from 12-27 years (X * sd = 17.6 k 4.2 years). The captive-born whales ranged in age from <1 to 8 years. In the Sea World breeding program (through September, 1993), there have been nine live births and one stillbirth, with eight calves part of the current inventory. Births occurred from July to February. Calving intervals ranged from 32-58 months. Female age at birth of first calves ranged from 8 years to an estimated 17 years (% C sd = 12.7 5 3.0 years). Gestation, based on conception estimates from serum progesterone analysis, averaged 17 months (X 2 sd = 517 i 20 days), but successful pregnancies with viable calves occurred from 15-18 months (468-539 days). Females, in the presence and absence of males, were polyestrus with periods of cycling interspersed with individually variable noncycling (presumed anestrous) periods ranging from 3-1 6 months. Mean serum progesterone levels (ese) were as follows: noncycling periods = 121 -+ 20 pg/ml; peak elevations during nonconceptive ovulatory (estrous) cycles = 3,962 & 2,280 pglml; first pregnancies = 14,592 5 3,854 pg/ml; second pregnancies = 8,389 It 395 pg/ml; and third pregnancy = 8,180 t 4,556.

Nursing parameters in captive killer whales (Orcinus orca)

“…SeaWorld has maintained killer whales in captivity since 1965 [Duffield et al, 1995]. Throughout the years, a total of 13 calves have been born at SeaWorld parks.…”

“…Studies of reproduction in killer whales (Orcinus orca) have focused primarily on parameters such as age and size at sexual maturity, fecundity and fertility, gestation, hormone cycling, and calving intervals *Correspondence to: Steven T. Clark, Corporate Zoological Operations, SeaWorld, Inc., 7007 SeaWorld Drive, Orlando, FL 32821-8097. E-mail: steve.clark@anheuser-busch.com [Bigg, 1982;Christensen, 1984;Walker et al 1988;Olesiuk et al, 1990;Robeck et al, 1993;Duffield et al, 1995]. Nursing behavior observations have focused mainly on bottlenose dolphins (Tursiops truncatus) [Reid et al, 1995] and beluga whales (Delphinapterus leucas) [Drinnan and Sadleir, 1981;Russell et al, 1997].…”

Estrous cycle characterisation and artificial insemination using frozen–thawed spermatozoa in the bottlenose dolphin (Tursiops truncatus)

“…Similarly to killer whales (Duffield et al 1995), bottlenose dolphins can be readily trained for unrestrained blood sample collections. Progesterone and estrogen analysis of these samples demonstrated that bottlenose dolphins could spontaneously ovulate, have an estimated 21 to 42 days estrous cycle (Benirschke et al 1980, Kirby & Ridgway 1984, Schroeder 1990) and that estrogens are elevated from 5 -7 days (Schroeder 1990).…”

Body Temperature and Circulating Progesterone Levels before and after Parturition in Killer Whales (Orcinus orca)

“…They live in water, which removes heat from a submerged mammal's body about 25 times faster than for the same body in air [1]. Reproductive endocrinology during ovarian cycles and pregnancy has been studied in captive killer whales [8][9][10]. However, other physiological changes during pregnancy and parturition have not been clarified.…”