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Collecting skin biopsies from large whales for genetic analysis is often subject to national permit, and in the case of cow-calf pairs, it maybe prohibited. We present results of 906 biopsy attempts on southern right whales (Eubalaena australis) in South African waters between 1995 and 1997, including 147 cow-calf pairs. Our sampling success was higher for biopsy darts with a bore of 4 mm compared to 4.6 mm. Contact periods averaged 17.7 min for cow-calf pairs and 25.4 min for whales unaccompanied by calves. There were no significant differences in the short-term reactions of males and females to biopsying, but the reaction of single animals of either sex was greater than for larger groups. Cows accompanied by calves had the strongest reactions, which were significantly greater than even single females. We found evidence of sensitization to repeat biopsying (over periods of hours to 65 days) for cows but not calves (n = 20). We compared the subsequent reproductive history of 117 biopsied cows with that of 163 unbiopsied cows from the same years, and we compared the distribution of calving intervals for biopsied animals with 829 intervals recorded from 1985 to 1995. We did not detect any adverse effects on the proportion of successful reproductive cycles, and hence calf survival, or the proportion of longer-than-normal cycles, although the power of all the statistical tests was low. We concluded that any prohibition on the biopsy sampling of cow-calf pairs should be carefully reconsidered in the light of the valuable genetic insights such sampling could achieve. [ABSTRACT FROM AUTHOR]

We collected behavioural data and skin samples for molecular sex determination from 327 right whales (Eubalaena australis) in the coastal waters of South Africa between July and October, 1995 and 1996, as well as from 147 cows with calves-of-the-year between August and October 1996, September and November 1997. Data on group size, composition and behaviour were also available for 85 sightings of right whales south of 40°S. Although right whales are considered to be relatively non-social, only 23.3% of animals (apart from cowcalf pairs) encountered in South African waters were alone (N = 649), compared to 84.6% of animals seen south of 40°S in summer (N = 94). Of the pairs other than cows with calves encountered off South Africa, 31.0% (N = 58) were believed to be composed of cows with last-year's calves (=yearlings): 93.3% (N = 15) of these yearlings were female, suggesting a possible mechanism for female philopatry. The incidence of these mother-yearling pairs dropped sharply after early August, indicating the abrupt weaning of some calves at an age of approximately one year. Most other animals were observed either in surface-active groups (SAGs) that indulged in apparent courtship behaviour, or in non-surface-active groups (nonSAGs). SAGs tended to be larger on average than non-SAGs (4.45 animals, N = 33, range 2-10, versus 2.57 animals, N = 108, range 2-5, respectively), and males predominated, while females predominated in non-SAGs. The number of animals participating per SAG increased through the season, whereas the size of non-SAGs remained constant. Given that most conceptions in southern right whales are estimated to occur in a 118-day period around mid-July, the observed increase in group size through late August and September may be due to declining availability of receptive females. Focal animals in SAGs proved to be predominantly female (83.3%, N = 24) and non-focal animals predominantly male (85.2%, N = 61): a few groups observed late in the winter season had a male rather than female focal animal. Sighting histories of the focal females revealed that none was seen with a calf in the 17 years that preceded the surveys, but four had been seen as calves, 2-5 (average 3.75) years previously. Six females were photographed with calves from 2 to 5 years after being the focal animal in a SAG, which is consistent with the observation that most focal females in SAGs were young, pre-pubertal animals, and therefore being the focal animal did not normally result in conception. It is still unclear where (and when) conceptions occur in southern right whales, but it is hypothesised that the focal females are practising a mating strategy in which the chances of conceiving with a larger male will be maximised. As neonatal survival is partly related to size, the female will in this way protect her substantial investment in time and energy represented by the calf. [ABSTRACT FROM AUTHOR]

This paper presents evidence of the presence and subsequent loss of postnatal skin in an ecdysis-like process in southern right whales, Eubalaena australis. Individuals whose skin was noticeably uneven, spongy, broken, and often light gray in color formed ≥20% of right whale neonates seen on the South African coast on any day up to and including the 1st week of September. Thereafter ≥85% of calves were of the normal, smooth-skinned appearance. The 50% transition point between the 2 forms occurred on 31 August (95% CI 1.1 days), or about a week after birth. Histological analysis of skin from stranded neonates showed a definite cleavage plane in the midepidermis, the mechanical integrity of which was further compromised by low concentrations of desmosomes and intracellular filaments. We propose that focal edema develops between the cells and forms the cleavage plane, which eventually leads to separation of the outer epidermal cell layer (cf. spongiosis in humans). The movement from the intrauterine to the oceanic milieu, and the osmoregulatory consequences thereof, may be a catalytic factor for this process to occur. This ecdysis may have important consequences for the cyamid fauna of neonatal right whales. [ABSTRACT FROM AUTHOR]