The subantarctic fur seal pup switches its begging behaviour during maternal absence

Abstract

International audienceBegging signals from the young are used to elicit parental care. Although honest and parent-directed signalling seems to be widely shared characteristic of begging behaviour, offspring might modify their strategy under some ecological or environmental constraints. In the subantarctic fur seal, Arctocephalus tropicalis, mothers forage at sea for 2–3 weeks at a time throughout the lactation period, resulting in regular separations of mothers and pups. Using playback experiments we investigated modifications of pups' begging behaviour during their mother's absence. From the 1st to the 5th day of maternal absence, pups rarely begged in response to other adult females' vocalizations (17.6–46.7% of tested pups), but always responded specifically to their mother's. After its mother had been absent for 5–10 days, the pup's response to playback of strange females' calls was stronger (46–69% of tested pups), but the specificity of the response to the mother remained. However, after the 11th day of maternal absence, pups become highly responsive to calls made by any adult female (up to 37% of tested pups). The variation in responsiveness of fur seal pups during their mother's absence may be explained by changes in their motivational state that were linked to their internal nutritional balance

Kin selection may influence fostering behaviour in Antarctic fur seals (Arctocephalus gazella)

“…as in the milk-stealing behaviour described in Antarctic fur seals; Lunn 1992), or are being tricked into providing milk. Adding credence to the notion that pups may be employing sneaky strategies to garner milk resources is the work of Charrier et al (2002a), which shows that subantarctic fur seal pups will change their begging behaviour in response to long periods of maternal absence. Under such a scenario a lack of maternal experience may contribute to the increased fostering behaviour, as in Antarctic fur seals (Lunn 1992).…”

Mother–young vocal communication and acoustic recognition promote preferential nursing in sheep

“…This is somewhat similar to results reported in other species, such as the seal, although it occurs over a much longer period in seals. Thus, the responsiveness of fur seal pups to maternal calls during the mother's absence varies according to their motivational state, which is itself related to internal nutritional balance (Charrier et al, 2001;Charrier et al, 2002b). More generally, this is congruent with the social modelling theory that suggests that input must be referentially and contextually applicable to elicit a socially appropriate response (Bandura, 1977;McGregor, 2005b).…”

Prevalence of allosuckling behaviour in Subantarctic fur seal pups

“…Numbers of adult females and pups in the observation area were counted every five minutes (for longer sessions), while the area was continuously scanned for any signs of milkstealing behaviour, as described in Roux, (1986). A pup was considered to be attempting to steal milk if it purposefully, but cautiously, approached an adult female quietly (without the usual begging vocalizations - Charrier et al, 2002). Furthermore, once close (1 m), if the pup made an obvious effort to remain undetected, usually by approaching the female from behind and often lowering its body profile, a milk-stealing attempt was assumed to be in progress.…”

“…Consequently, juveniles would be advantaged by attempting to steal milk as often as possible, whereas females would be advantaged by being able to identify milk-thieves, thereby preventing indiscriminate theft. This is the basis of the misdirected maternal care hypothesis (Packer et al, 1992;Roulin, 2002), whereby non-filial maternal investment or fostering may result from recognition errors by the mother (Charrier et al, 2002;Insley et al, 2003), or arise without the female's consent, if she is unaware of milk-stealing (Roux, 1986;Lunn, 1992). Non-filial offspring therefore need to either steal milk unnoticed, or acquire it with the erroneous consent of a lactating female.…”