Juveniles come to rest
Beginning in late summer and throughout the fall, juvenile elephant seals come to the rookery for a month off from the rigors of ocean life. These seals include the new of the year who are making their first return to the rookery where they were born the previous winter. While there is no conspicuous purpose for the visit – no molting, no birthing and breeding – this visit is very important for their development. It instills the pattern of two visits a year, essential for their adulthood; it strengthens the bones and muscles essential to their land existence and it gives them experience fasting.
The seals arriving for this “fall haul-out” period are up to five years old although most females of that age will be pregnant and stay at sea until the December - January birthing period. Survivorship studies of the elephant seals indicate that only one in six survive to reach age four so juveniles constitute about 80% of the colony. The population in the rookery reaches one of its three population peaks around the first of November, the other two being the peak during birthing around the first of February and the juvenile – adult female molt with a peak around the first of May.
The period is marked by friendly combat between males, both on the beach and in the shallow water. Not only do these combats rarely draw blood but the sparring seals are invariably of equal size and, presumably, age. They appear to be having a very good time just as young human males enjoy roughhousing with their friends. We can see how this activity for the seals serves as training for their serious battles later in their lives when it is vital to having access to females. It is likely that the same play instinct in human (and dog and cat …) males arises from that same purpose.
It is interesting to contrast life at sea with life in the rookery. In the rookery, all seals except nursing pups, are fasting – no food or water; at sea they spend almost all their time foraging. In the rookery they like to cluster together sociably; at sea – ten months out of twelve for the juveniles – they are solitary. In the rookery they spend most of their time sleeping with half of that time without breathing; at sea they are intensely active with an annual migratory distance exceeding that of the great whales. Finally, the muscles they use most on land are quite different from those most important to life at sea.
The development and implementation of the LiveCam has been a joint activity of Friends of the Elephant Seal and the California State Parks of the San Luis Obispo Coast. This development and its continuing operation are made possible through the generosity of our many friends and members.
Note: Viewing the video requires Adobe Flash.