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Monk Seal Fact Files

Mediterranean Monk Seal

(Monachus monachus)

Biology

Moulting

In contrast to all other pinnipeds, which shed their hair individually, Mediterranean monk seals shed their hair along with large layers of epidermis (Badosa 1998).

Neonatal moulting has been observed to follow a well-defined pattern in rehabilitated pups (Androukaki et al. 2002).

Observations in the Cabo Blanco region suggest a two-month period between birth and first moult, while other reports indicate pups moulting for the first time at an age of four (Androukaki et al. 1999) five (Dendrinos et al. 1999) and six weeks (King 1983, Caltagirone 1995). The first moult is, however, not associated with weaning because several moulted seals have been observed to be suckling (Gazo, Lydersen and Aguilar 2006).

The first moult may last 1 week (Mursaloglu 1986) or (seen in pups undergoing rehabilitation) 2-3 weeks (Androukaki et al. 1999). The earliest completion has been observed within the 8th week of a pup’s development (Dendrinos et al. 1999).

Moulting of juveniles and adults occurs also over a very protracted period, extending throughout the year, but is less frequent from June to August in Greece (Androukaki et al. 1999, Güçlüsoy and Savas 2003a) and in January or June at the Cabo Blanco colony (Pastor & Aguilar 2003). Overall, however, there appears to be no significant difference in the moulting period between monk seal populations in the eastern Mediterranean and the Cabo Blanco region (Badosa 1998).

A series of sequential moulting stages has been identified, which included a long pre-moult phase (brown pelage) and a post-moult phase (dull appearance). The shedding process lasts 15 days and differs from that of the Hawaiian monk seal and elephant seals, as Mediterranean monk seals moult partly in the water. The intermoult period was close to one year except in females nursing a pup. Such females have longer intermoult periods and can even moult whilst still lactating. In males, the process of developing the mature pelage pattern of bulls is gradual. It involves at least two annual moults and can be completed by the age of 4 yr. (Badosa et al. 2006).