Sunday, December 18, 2005

JD, Beachmaster of Sandflat, Deposed by Nero


JD, previously undefeated beachmaster of Sandflat harem for the last two years and sire of perhaps 180 pups, was soundly defeated and deposed today by a young bull named Nero from the Point Reyes colony. Nero held a small harem of eight cows last year on the Marine Terrace, but has definitely moved up in the world with the outcome of today's bout. Cow elephant seals can only mother a single pup each year during a breeding lifespan of 10-15 years, but in two years JD probably fathered ten times more progeny than any cow possibly could. But that fecundity has a price, a short brutal life of ceaseless battling for dominance. This sort of breeding system is what produces such secondary sexual characteristic oddities as the Elephant Seal nose, Elk antlers, and male Fur Seals that are 5 times larger than females, the biggest difference between the sexes of any mammal.

2 comments:

rcferris said...

I understand that there were a record number (40+)of NFS births last year. Correct? Any sense of this year?
Thanks

Los Farallones said...

Hi rcferris! Northern Fur Seals bread here on the Farallones in late Summer/Early Fall. The NFS census in late August 2005 lists 24 pups born for that year. In total SEFI had indeed a record number of fur seals during that summer, a total of over 90 animals, the highest number counted ever since these seals were hunted to extinction here on the Farallones in the 19th century. During the winter season there is only the occasional fur seal about, our only West End trip this season so far only had 1 immature fur seal there. We hope this summer they will fare as well as last summer.