Recent success propagating captive beluga has resulted from combined efforts by North American zoos and aquariums to manage disparate collections as a single population. This success has provided a tremendous opportunity to increase our understanding of beluga reproductive biology. Blood samples were collected on a weekly to biweekly basis from 23 female and 12 male beluga, ranging in age from 2-15 years, for analysis of serum progesterone (P) and testosterone (T), respectively. Peri-parturient observational data, including food intake, duration and signs of labor, and nursing patterns were collected from 15 days prepartum to 30 days postpartum during 21 births. Total body lengths and weights were collected from 10 captive-born beluga. For female beluga, the mean (7SD) age, body length, and weight at first conceptions were 9.172.8 years, 318.079.1 cm, and 519784 kg. Thirty-five luteal phases and 13 conceptions were detected from January-June, and 70% of luteal phases and 80% conceptions occurred from March-May. The mean luteal phase and total estrous cycle lengths were 30.076.5 days and 48.074.6 days, respectively. For male beluga, the mean age that males sired their first calf was 13.372.6 years. Compared to younger males (o8 years of age, 0.95 ng/ml), levels of T secretion in older males (48 years of age, 5.0 ng/ml) were elevated significantly only during the interval from January-April. Highest T concentrations (6.274.9 ng/ml) were recorded from January-March, whereas nadir concentrations (1.171.0 ng/ml) were detected from August-September. The mean gestation length was 475.0720.4 days (n ¼ 9). For parturition, the mean time from the first appearance of fluke or rostrum to delivery, delivery to placental passage, and delivery to nursing were 4.472.9 hr, 7.671.8 hr, and 43745 hr, respectively. All cows had decreased food intake on the day of delivery, with 44% having zero intake. Peak 24-hr nursing activity occurred 3.972.7 days post-partum. Growth (i.e., body weight and length) as a function of age were well described by the Gompertz model (r 2 ¼ 0.91, 0.93). Based on the model, growth in body weight and length were significantly greater in males compared to females. Predicted birth weight (88.9 kg) was similar for both sexes, however, and male calves were predicted to be shorter (154.3 cm) than female calves (160.7 cm). The results provide the first descriptions of captive beluga reproductive physiology, including endocrinology, peri-parturient behavior, growth, and reproductive maturity. This knowledge is important for helping to maintain genetically diverse, self-sustaining populations of captive beluga whales.

Three albinistic, white‐spotted bamboo sharks (Chiloscyllium plagiosum) (two males and one female) were hatched at SeaWorld parks. Due to their lack of integumentary and retinal pigments, all three animals were considered true albinos. The term “leucism,” more prominently used within the herpetological discipline, is suggested as a more apt description for previously reported color aberrations in elasmobranchs. Reports of color aberrations in other species of elasmobranchs, and a clarification of the terms used to describe these irregularities in pigmentation, are also presented. Zoo Biol 21:519–524, 2002. © 2002 Wiley‐Liss, Inc.

Morphometrics from 25 captive killer whales (11 captive‐born) were collected at SeaWorld parks from 1984 to 1995 to determine age‐specific growth parameters. For sexes combined, the body‐volume index was the most accurate predictor of body weight. However, predicting weight from total length was appropriate, although it may underestimate weight of pregnant animals. Among captive‐born calves, a Gompertz model was the best predictor of weight and length at age. Estimates for length and weight at birth were done using data from in utero and neonatal calves. For ages 1‐5 yr, models indicate that males grew in both weight and length at slower rates. Growth rates in males may surpass those of females at approximately 5‐6 yr of age.

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