I got an opportunity to work with Dr. Christin Taylor Murphy photographing Sprouts, a harbor seal (Phoca vitulina)and Rio, a California sea lion (Zalophus californianus) for publication. I have worked with sea lions and northern elephant seals (Mirounga angustirosus) in the past at as a volunteer at The Marine Mammal Rescue Center. There it was mostly malnourished pups and sick or injured adults. I’d never been around fully grown adults. It’s incredible to be mere inches from these powerful animals. For all the awkwardness they exhibit on land, their grace in the water is astounding! They’re highly trained, but there’s always the awareness that you are dealing with a very large, very powerful predator. Ultimately when you’re in the pen with them, you are in their world!
And that’s Rio!
Seals mammals like us, and are in the Pineped Class along with the walrus (odobenus rosmarus). There are two types of seals, the phocidae (earless or true seals) and the otariidae (eared seals)
If you look back at those photos you can see Rio’s ear flaps behind her eye. There are a lot of differences between them, how they walk, swim, feed their young, breed, and live out their lives. If you want to know more about that, Noaa has a reasonably good comparison.
Dr Murphy works on a pretty amazing thing that seals can do. Some time ago researchers would notice a blind seal somewhere. They assumed (pretty reasonably) that it would die quickly in the wild since they have to hunt to survive. But then, year after year, that same seal would still be around as fat and happy as a seal can be
(As an aside: Scientists don’t like the word ‘happy’ when applied to animals. It’s considered anthropomorphism. It’s only recently that a number have come out and decided that we should consider many self-aware. Science is very cool, but it requires rigorous testing and strong logic to make any claims.)
Back to the subject at hand! So these seals had some way of detecting and tracking prey in the wild. Smell doesn’t work… Hearing only works with echolocation which seals do not do…
how do they do it?
They use their whiskers to follow the wake. Whenever something moves through a fluid it displaces the liquid and creates turbulence behind it. The seal is able to detect the turbulence by changes in the vibrations of their vibrissae (whiskers).
As you can imagine, the researchers have to make sure the seal can’t see when underwater so Sprouts and Rio got a sponsorship from Hotline Wetsuits!
Dr Murphy spent two years working with these seals and training them so they could take a test and let her know what they knew. It’s a bit like a masters only with fish as the reward instead of a diploma. That being said the animals enjoy working. As carnivores, they are highly goal-oriented in the wild and get bored without problems to solve.
I came and helped by providing photo documentation, editing and video editing support. I also got to work with phantom video shot by the discovery channel, processing and rough editing footage from raw… It is nothing short of gorgeous! I want to get my hands on more of it someday!
If you want to find out more and see the videos, here’s the paper:
PLOS ONE: Effect of Angle on Flow-Induced Vibrations of Pinniped Vibrissae.