They breed like cloned rabbits

. . . underwater rabbits, that is. A couple of small anemones arrived in the aquarium towards the end of last November. By the first week of December, one had split iself down the middle twice. A few days later, there were 2 more. These 5 then cloned themselves, making 10. And so it went; at last count, there were about 50.

They started out on the wall of the aquarium, up near the water surface, but now that space is crowded, and they've begun to move to the seaweed and stones in the tank. One group is hanging out on the water pump, making a nuisance of themselves when I need to change the filters.

On eelgrass. The column is less than 1/2 an inch tall.

On a brown seaweed, against a background of Turkish towel.

As far as I can tell, these are the orange-striped anemone, Haliplanella lineata, an import that probably came from the far side of the Pacific. (The stripes may be either orange or white, against a greenish background. Most of the ones in the tank are quite pale, maybe because of the light levels or diet.)

These anemones may breed sexually in their home territory, but elsewhere they clone themselves, either by splitting down the middle, then moving apart, or sometimes by just moving over, leaving a tiny blob of tissue behind. A few days later, the blob is a fully-functioning anemone.

They eat tiny swimming organisms; copepods and baby amphipods, etc. Sometimes I give them a treat of mashed shrimp, or they'll catch a pellet of hermit crab food, swept their way by the current.

Anemones and other wanderers

Residents in my aquarium, some new, some old:

A medium-size grainy hand hermit, Pagurus granosimanus.

These hermits like a shell 'way too big for them. It seems impractical; all that weight and bulk to haul up the blades of eelgrass, but they persist. They don't seem to mind a tumble or three.

Look inside the shell; his small fourth leg, the one he uses to hold the shell in place, is visible.

Orange lined anemone, Haliplanella lineata, on vegetarian snail.

I brought this anemone home on a small stone. Within hours, it had packed up and left. I found it a few days later on the back of the big abalone shell, and a day later, inside the lip. A few days later, after more moves, it met this snail. The snail travels around the walls, down into the sand, up a wall again, eating algae. And the anemone, finally, is content to stay put and let the snail do the chauffering.

Stubby isopod, Gnorimosphaeroma oregonensis*, on a blade of eelgrass

A bunch of these, at least 30, came home on the eelgrass I brought for the hermits. Most of them are very tiny, barely little specks that alternately swim and crawl. When I try to capture one, it rolls up into a tight ball, like a pillbug does. This is one of the larger ones.

*His name is bigger than he is.

Val, growing bigger every day. Last I measured, her tentacles were 4 cm. long.

And she's another wanderer, more of a homebody than the snail rider, but never content to stay in the same corner for too long. Now she's at the far back of the aquarium, making me almost stand on my head to get a good look at her.

Barnacles and snails

Not even the barnacles stay put around here. Sure, they're glued firmly to their base, but in this case, the base is the empty shell of a larger barnacle, and it rolls about as the snails and hermits walk over it or the current takes it. On the beach, they wouldn't survive; they'd be tossed up on shore to dry, or eaten by a passing fish. In the aquarium the only thing they need to fear is Val, and the pump is set so that the current sweeps them away from her.

Good news!

Two years ago, in November of 2011, polluted water from the White Rock beach killed my aquarium. A month later, we found a zone of the beach that was basically dead, too.

There were no crabs under any of the rocks I flipped. No hermit crabs. No snails. No limpets. No worms. A few of the higher intertidal amphipods that always swarm on the bottom of these rocks. Just a few.
I walked west, flipping a few more rocks after every couple of steps. Nothing was alive but the amphipods.

We've been back, off and on. The view is always beautiful, but so often, I flip stones and find nothing. With time, even the barnacles were all dead. The rocky west end stunk of a cannery in summer; a long-dead fishy odour. I was beginning to dread walking that direction.

Last week, we headed that way again. It had been a while. And the beach is back! It smells fresh and salty, as it should. I flipped rocks and disturbed whole communities of hermit crabs, hairies, grainy hands, and those little orange ones I can't identify. Shore crabs scuttled away to hide, or stood their ground, menacing me with their mighty half-inch pincers, according to their various personalities. Big eelgrass isopods slept on the bottoms of stones; polychaete worms burrowed into the sand away from the light. The stones were dotted with pinhead snails, probably periwinkles.

I collected a bit of eelgrass for my critters in the tank. Washing them off at home, I found tiny limpets. One blade held at least 10, plus a raft of spiral tubeworms.

And the barnacles and mussels are growing back.

Detail of a stone top.

And flatworms! I'd never seen so many at one time before. Every stone held a few; on some stones, every barnacle seemed to have a flatworm oozing around it.

I count 7 flatworms on this corner of a rock. I don't know if they're the same species or not. Since their bodies are semi-transparent, whatever they've been eating changes their colour and pattern.

Not all the ooze on that stone is flatworm. The more shapeless and patternless blobs seem to be some sort of sponge.

And I've never seen these anemones anywhere but near the American border on the Tsawwassen beach. I didn't see them when I took the photos, but at home, counting flatworms, I noticed quite a few. And two came home on three barnacly stones I brought to feed my one predatory snail.

Orange-striped anemones. Five here, plus one flatworm that I can see. This corner of the photo was blurry, and I've sharpened the anemones to make them stand out.

We walked quite a distance west from the end of the park. I flipped stones at intervals all the way. Every stone harboured a thriving community.

I am so relieved! Life on the edge is tougher than it looks.

Simple aquarium arithmetic; multiplication and division

Another aquarium post (It's good to be doing these again!)

Among the crabs and shells that we collected on the beach a week ago, was a small stone with an anemone so small that without a lens, it was almost invisible. I noticed it because it felt soft and jelly-like when I picked up the stone.

At home, in the aquarium, it promptly left the stone for more congenial quarters. I saw it next on a bit of eelgrass; then the grass rotted away, and the anemone seemed lost.

A couple of days later, it turned up half way up the glass wall of the aquarium, and has been there ever since, a pale green circle about 3 millimetres across, sometimes waving white tentacles about. Then this morning, there were two, one smaller than the other. The anemone has cloned itself!

The circular bases are warped where the two split apart. 

At first, the two anemones were side by side, but over the day, the smaller one has moved up and away. I think they're the lined anemone, Haliplanella lineata; in ordinary daylight, the original was a green colour, with a hint of orange lines. These are fairly common on Boundary Bay beaches, but are so tiny that they're usually overlooked.

While I was at it, I took a few photos of the damaged burrowing anemone, "Val". It has regenerated the entire circle of tentacles, and has grown a bit, as well. There is still some healing work going on in the mouth area.

Val of the hearty tentacles.

Notice the water currents; the location chosen by the small anemones is in a high current area. I took the photos with the pump going, and you can see the lines made by the bubbles streaking by. Below, on the floor where "Val" sits, there is still movement, but the lines are short, curvy, and chaotic. Just the way Val likes it.

One of the larger, but still small, hairy hermits, in a periwinkle shell.