Natural History Story
This past weekend, I was lucky enough to see Northern Elephant Seals. Año Nuevo State Park offers guided public walks to see these beasts, which come to this beach to breed. They are large and quite heavy, with males weighing in around 5,000 lbs. Looking at the seal's skin, you can see many scars and areas of very rough skin on the neck and snout. This is due to the fights between bulls over territory on the beach for breeding. The males arrive before the females and establish a territory on the beach. They use loud snorts and aggressive behavior that can result in confrontation. When the males fight, they charge each other head on and open their mouths so they can hit each other with their teeth. Although blood is shed, these fights don't typically end in deaths. The lesser males will flee and the males that are best at fighting get the best areas and the right to breed. Northern Elephant Seals are polygynous, so earning this territory allows them to breed with a harem of females.
While I was at the park, the tour guide noted an interesting story about how this species was almost extinct. These large seals were hunted for their blubber which was used for oil and were thought to be extinct by 1870's. A population was found in Baja California in the early 1880's but the seals were killed within a few years. Another, much smaller, population was found off the coast of Baja, and like the first group, was promptly killed. In 1892 a eight individuals were found on Guadalupe Island, and killed to be brought back to the Smithsonian. Seals continued to show up on this island in following years, only to be killed by poachers and museum collectors. The species was reduced to very low numbers, but still managed to survive long enough until the governments of Mexico and the United States started to protect them. The species has grown tremendously since then, but has very low genetic diversity since they all descended from the same 50-100 individuals.
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