Friday, September 30, 2011

Spineless of the West Coast Trail

The West Coast Trail on the west coast of Vancouver Island is one of the most remote coastlines you can explore in Southwest BC.   It is a 75 kilometre foot path connecting the towns of Port Renfrew and Bamfield with untouched forest on one side, and nothing but the great Pacific on the the other.  When the tide is out, we traverse around the tide pools, balancing carefully our 40+ pound packs on our backs without slipping on the algae covered rocks.  The absense of heavy industry allows animals to flourish here where you'd be hard-pressed to find within the vicinity of Vancouver.  As Wanderin Weeta points out, invertebrates tend to be the most sensitive to pollution and human activity.  This far away from civilization, I expected to see lots of biodiversity.

It's not often that I see sea urchins, washed up intact, but the pounding surf is quick to toss any weak urchins onto the beach

Amphipod of some sort.  They were larger than the sand hoppers, and didn't seem mobile on land.  This one twitched on the sand, leading me to believe it was tossed out of its native habitat.
About three of our eight days were in the forest.  We took a break by a river one day, and saw this:

My guess (yes, just a guess as I know very little about worms) is that it is a horsehair worm, a parasitic worm that spends most of its life parasitizing an insect like a grasshopper.  It has an amazing ability to take over the mental capacity of its host, causing it to jump into a pool of water at which point the worm erupts from the insects abdomen.  It spends the rest of its adult life in the water, where it can lay up to 27 MILLION eggs.  The eggs hatch, become free swimming, and are ready for any ingestion by any insect drinking from the water.  The life cycle repeats.

Now, back to the non-freaky ocean.

A pool of aggregating anemones

Gooseneck barnicles amongst the mussels and limpets. I've only ever seen these on the west coast of Vancouver Island (ie. never on east side of the island)

A purple shore crab ambivalent to the hikers stomping past him while filtering through the sand

One of the two vendors permitted to sell food to hikers sells fresh crab from his floating restaurant

Not too crabby

One of the largest purple shore crabs I've ever seen.


In grade 5, during a science class segment on marine biology, we were introduced to a bunch of sea creatures (on b&w photocopies) that inhabited the intertidal zone.  The keyhole limpet was the only one that I hadn't seen in the wild up to that point.  Whenever I see it now, I ponder how odd it was that they put such a rare animal on a list of things that school-children should remember.
One doesn't have to hike the entire 75 km of the West Coast Trail to see all of this.   In Port Renfrew is an aptly named, "Botanical Beach" just about 20 minutes from the parking lot, where at low tide, you'll be able to see most of these creatures.

Next post: The Spined of the West Coast Trail


zoltan said...

Great article Tim. As usual I like the pics.
I keep thinking we missed a great trip. Imagine - we would have had our very own naturalist.

Tim said...

Thanks for the comment, zolt. D wants to do the north coast trail one'll hear an invite from us if we ever decide to do it.

Konrad said...

That last creature reminds me of a sandcoin, which I only remember hearing about as a kid. Bena and I plan to do the westcoast trail one day...