Wednesday, April 29, 2009

Watching where we step

On a mile-wide, featureless, sandy beach, what is there to see, besides sand and sky? Plenty. But it's mostly in hiding. I've been having fun blowing up our photos of Sunday's walk to full size, to see what we missed.


Sea lettuce and a mudflat snail, Batillaria attramentaria. No telling what's underneath.


Brown seaweed, probably a dulse. Eelgrass and roots.

So far, so good. Eelgrass and seaweed are easy to see. But look again! See those little yellowish dots on the eelgrass? They're egg cases, possibly of the Black Dog Whelk, Illyanasa obsoleta*.

Here are some more, doing their best to blend in with the bubbles.


Brown tuft, navel-lint algae. With eelgrass and snail eggs.

The snails are even better at hiding; they burrow right under the wet sand. I dug a few out; mostly Black Turbans, and a whelk or two. One on the upper left, below, looks like a mudflat snail, going by the shape.


In a photo of seaweeds and eelgrass, I found this tiny collection:


White tube discarded by a worm. And what looks like whelk eggs. (Nucella sp.)

If I had seen this at the time, I would have taken a close-up. But they were so small, I missed them even on the first two examinations of the photo.

This tangle of weeds and -- something -- is intriguing:


What is that red, segmented, tentacled thing? Worm or weed?


A close-up of the end, with "tentacles". Some kind of spaghetti worm? **

This is a worm, at least. We found it writhing in an inch of water. It's about 6 inches long.


Red-banded Bamboo worm, Axiothella rubrocincta. The red rings are bristled. (Barely visible.)


Clear view of the tail end. The head is already back under the sand, and digging fast.

Their tubes were scattered here and there around this area of the beach, mostly poking just an inch or so above ground. The worms stay in these tubes; I wonder why this one was on the surface.

On the opposite side of the bay, at Boundary Bay Beach (and this is all Boundary Bay, but this side is Crescent Beach), the sand is dotted with the fecal castings of lugworms. On the Crescent Beach side, the coils of worm poop are less frequent, smaller, and finer. Look for them around these geoducks:


Pacific geoduck, Panopea abrupta. Up to 9 inches across the shell, and 20 lbs. Lifespan: 168 years!

When I touched this geoduck (pronounced gooey duck) with a toe, it retracted itself back under the sand, squirting at me as it went.


A horse clam, covered with algae and seaweed, and accompanied by grey mounds of worm poop.

(Update: I had identified this as a geoduck. I was wrong. Looking more closely at the siphon mouth, I realized that the edge of the mantle is tentacled; this identifies it as the gaper, or horse clam, Tresus nutalli. (The tentacles are green, which distinguish it from T. capax, where they are gold. I still think, though I could be wrong, that the first one is a geoduck. Neither it, nor one other similar one that we photographed show any sign of tentacles, and the other one has the characteristic one siphon, two openings of the geoduck.)

Look in front of the clam siphon; that brown coil is not lugworm poop; it looks more like a ribbon worm of some kind.


Mouth of the gaper clam.

One last critter. There were quite a few of these. But we never saw them unless we were about to step on them; then they shot out of the sand, sped a few feet away, and -- disappeared, even though we were looking right at them. One moment they were swimming, the next, there was not a trace of them.

Can you see the tidepool sculpin here? I have increased the contrast to make him stand out.


Tidepool sculpin, Oligocottus maculosus. Supremely camouflaged.

So many new things! So much to learn! What fun!

* Photo in Marine Life of the Pacific Northwest, MC198, p.228. Also, see my last year's post, No boots, no bags, some goodies anyhow, for macro photos.

** It's really an eelgrass root, with its rootlet "tentacles".

.

2 comments:

  1. I think going beach combing with you would be sublime! So much information in that little blog stroll. I have a wonderful book of sketches and info about the tidal life on the coast of SC. I think if I lived near the beach I would have to get acqainted with everyone of them! Enjoyed this post.

    ReplyDelete
  2. We'll have to do that, one of these days! Take a holiday, come to BC!

    ReplyDelete

I'm having to moderate all comments because Blogger seems to have a problem notifying me. Sorry about that. I will review them several times daily, though, until this issue is fixed.

Also, I have word verification on, because I found out that not only do I get spam without it, but it gets passed on to anyone commenting in that thread. Not cool!

Powered By Blogger