Sea otters - see otters!

A pair of sea otters floating blissfully on their backs.  Alaska.

I have seen sea otters a few times - certainly at the Vancouver Aquarium and in the wild earlier this year while visiting Victoria, BC.  But this was the first time I got a good look at them in the wild, especially with them floating on their backs in their peculiar manner.

Sea otters are remarkably important creatures in marine ecosystems.  We think of their cute fuzziness and clam-pounding exploits as humerous and endearing, but what we don't realize is the important role they play where they live - or used to live.  You see, sea otters have especially dense fur that was sought after by fur hunters of the day.  Overhunting caused populations to plummet, which led to an unsettling occurrence.  The death of kelp beds.

Kelp beds are important habitats for many marine creatures.  Besides providing oxygen and food, the beds provide thick hiding places for fish.  Like coral reefs, the tall kelp plants - the forests of the ocean - provide refuge and a safe haven for organisms.  When the kelp is taken away, the refuge disappears.  So, what do otters have to do with disappearing kelp?

One of the mainstays of sea otters' diet is the sea urchin.  Like starfish, sea urchins will crawl over the bottom of the ocean, eating everything they can lay their tiny mouths on.  Sea otters keep the urchins' population in check.  When the sea otters disappear, the urchins' population explodes.  The spikey creatures cover the ocean floor eating everything they can find.  Like miniature lawn mowers, they crop the kelp base (holdfast) and the rest of the kelp floats away.  

It's like a chain reaction. No otters, no kelp, no fish.  Their populations are slowly returning, but it will likely take them many generations to return to pre-industrial levels.  You know, before man was around.

Thanks for reading.

Eric Svendsen     www.ericspix.com