Monday, January 23, 2012

A Guided Walk Through Blubbery Giants

A Picnic By The Sea

Steve took the day off work so we could go on a guided Elephant Seal hike.  We decided to have a picnic on the beach next to the state park of Año Nuevo where we previously saw an elephant seal.

This photo is from a previous day on the same beach in December 2011.
This beach is unpatrolled so if there are Elephant Seals on the beach you need to use your common sense and not go within 25 feet to them (more on the dangers of Elephant Seals below). It's a very large federal offense to annoy or interfere with marine life in California. One local marine biologist is facing possibility of a 20 year prison sentence for supposedly feeding Killer Whales in the wild.

There were no Elephant Seals to be found on the beach during our picnic. The tide was in fairly far on the beach so we settled on to a grassy outcrop. 

We entertained ourselves with the antics of shore birds. 

I don't know exactly what kind of shore birds these are but they were very entertaining as they would run away from the waves as they crashed into shore, then chase after them to feast upon the goodies that the receding wave uncovered. Every once in awhile a bird would panic and start flying, generally causing the whole flock to panic and fly around for awhile before they settled back down again. 

It was a delicious lunch with fantastic company and hilarious entertainment.

There Be Giants

Año Nuevo State Park requires you to book ahead for your guided walk to the Elephant Seal breeding grounds. All the walks on the weekend were completely booked by the end of December, hence Steve taking a Monday off work so we could go this year.

At the touching station before our hike was a collection of marine oddities. We were able to pet a Sea Otter pelt (so soft, no wonder they are endangered). Steve is holding up a Great White Shark tooth. Imagine a mouth with multiple teeth that large latching onto your arm *shudder*.

I am sticking my head an actual skull of a male Elephant Seal. Elephant Seals are carnivores and the males can weight up to 5000lbs or 5 tons. Their female counterparts weigh in at a measly 1000 lbs or ton. Elephant Seals are the largest of the species classified as pinnipeds - larger than even Walruses.

Our guide stopped by this sign to ensure we all understood we were walking through the equivalent of an Elephant Seal's bedroom and living room.  We learned that Elephant Seals can travel on land in short bursts up to 25 miles/hour - much faster that humans can run on sand. 
In essence - if you see the guide run, you run.


The path we had to follow to view the Elephant Seal breeding grounds had already changed 7 times that day (we were on a 1:45pm tour).  The Elephant Seals were active, climbing into the sand dunes. When an Elephant Seal blocks the tour path, you don't move it - you move the path. 

 For a section of the walk we were instructed to walk single file, stay close, and don't stop to take more than a point-and-shoot photo. There were Elephant Seals on both sides of us and we could hear other males we couldn't see by their distinctive calls.

 Weaving among these giants was an amazing experience.

Of Mothers, Starvation, and Survival

Just when we thought it couldn't get any more epic, we reach an outcropping where we can view a beach littered with male, female, and baby Elephant Seals.


The males arrive to Año Nuevo in the first week of December. The state park is closed for 3 weeks during this time to allow the males to settle in and set up territory.

 Then the females arrive. The females come to Año Nuevo already pregnant from the previous year, ready to give birth to their pup.

Elephant Seal pups are born at 60lbs. The majority of the pups will be female. 

 An Elephant Seal mother's milk is 60% fat. Compared to a cow's milk at 3% and human's breast milk at 2.5%, those pups will get big fast.

 There is no recorded birth other than single births for Elephant Seals. One of these pups has been separated from it's mother.

The mother weans her pup for 2 weeks. Then she mates with the dominant male who has secured her position  and heads back out to sea to feast. Elephant Seals have a gestation period of seven months, but after mating in the late winter, they always give birth the next winter. This is because of embryonic diapause (delayed implantation). Their egg becomes fertilized before they head out to sea and the zygote develops to a certain point and then goes into stasis for a few months. Biologists don't know what exactly triggers the time for continued development, but this process is not rare in pinnipeds and a number of other mammals do the same.

So where does that leave this year's pup?  
The pup is left on the beach. On it's own, with no lessons in hunting, it is confused as to why they no longer have a food supply. This 3 week old pup is hungry. Very hungry. And she doesn't know what to do about it. In the photo she's trying out leaves.

The pups that don't figure out that dinner is located and hunted for at sea die of starvation.  Even the pups that do figure out where to go for food may not survive to the following year. A full grown male Elephant Seal has no natural predators. The females and their vulnerable pups are a different story.  Great White Sharks and Orcas know the time of year to stalk the shores of Año Nuevo for an easy lunch of a confused and hungry pup. 

It's easy to anthropomorphize this photo as a loving Elephant Seal family, with a mother and father talking, and the young child protected between them.
In reality the male is attempting to breed with the female who is not ready for breeding. She is posturing (and making her chain saw like scream) to get the male to back off as she is still weaning her pup. Pups are known to get crushed by males and females other than their mothers if they stray too far.

All these factors add up to a pup mortality rate of 50% in their first year.

Of Noses and Territory Disputes

The male Elephant Seals collect females in harems. On the open beach a large male can defend a territory containing 20-25 females.  The best story from the guide was when he told of a male that secured a harem of 150 females. He herded them into a valley with a bottle neck entrance. With only one entrance, the male only had to defend a small portion of land. Brains and brawn maximized the propagation of his genes.


This male was shuffling into the territory of another.  Prepare to witness why running from Elephant Seals on sand may be problematic for the human.

Notice the "whale eye" the fleeing male displayed. The whites of the eye displayed in that manner indicate fear or panic in a mammal. The dominant male in this case was much larger and older than the encroaching male. 

How do you determine the age of a male Elephant Seal? 
Check out the nose length.

The longer the nose, the older the male.

The nose of the male Elephant Seal also acts as a moisture rebreather. When the males are on land during breeding season, they neither eat nor drink. Their nose captures moisture expelled through their mouth while vocalizing and breathing. When I learned that I had a flash back to a scene in the movie Happy Feet where the Elephant Seal sucks on his nose. I don't know if they do that or not but I can't stop thinking about it.

When the males make their "burping" vocalizations, a vapor also exits their mouth.

The Elephant Seal with the markings above defends his harem territory from two encroaching males.

(The female's bark can be heard here. Steve remarks that it "sounds like a dirt-bike")

The point is to gather all the females together while they wean their pups so that they will choose you when they are ready to breed.

Scarification occurs on the older male Elephant Seal from fighting for dominance. 
Many males had open wounds from powerful blows during fighting.


Of Extinction and Genetic Population Collapse

This tour was fantastic simply for being able to approach and observe such a large animal during breeding and whelping. 

It was even more exciting to have been able to witness this species once we learned that in the 1880s they were thought to be extinct.

Elephant Seals were hunted to near extinction for oil to run lighthouses and lamps. Genetic studies reveal that their population shrank to the size of about 100 individuals in 1880. It may seem exciting to think that they now number in the tens of thousands but genetically, they are all cousins. 

A species that drops below 1000 individuals is at high risk even if their numbers rise in the future because they do not have enough genetic diversity or mutations. One virus transmittable from Elephant Seal to Elephant Seal would find little resistance, causing the whole population to collapse. 

For this reason they are still considered to be at a high risk of extinction.

We'd like to say this tour was an experience of a life time but let's be honest, we'll be back next year.

2 comments:

  1. I think the birds are called sand pipers, at least that's what I've always called them. Never seen so many together though!

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  2. Yea I was wondering if they were sand pipers. I think there are multiple types of sand pipers as well.

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