Feet in mouths

While I've been snowed in, I've been combing through my hard drive, looking for forgotten projects, and I found a folder full of unprocessed segments for videos, some old, some very old, a few newish. Some, with minimal processing, are worth sharing.

Here's one; a look at barnacles feeding, combining a new clip with a very old one:

(I've skipped the musical accompaniment, which is time-consuming and probably adds little to the video, anyhow.)

And the snow has begun to melt, it's raining, and the snowplow has come down my street. I'm outta here!

Make it a double

Crabs, when they find transportable food, grab and run; they don't hang around in case another crab mugs them for their catch. They take their food back into hiding under a shell or a dark corner of seaweed, and eat it there.

Hermit crabs, on the other hand, take their time, poking around, seeing how much they can gather (or steal) before they settle down to eat. This grainy hand hermit has collected two pellets, and has been cruising back and forth in the feeding area, looking for more.

"I still have two pincers free; I can handle at least two more nuggets!"

When he's got all he can carry, he'll climb the eelgrass with it; hermits like dining rooms with a view.

Corn-fed shrimp

The label on the shrimp's favourite food says, "Crab Cuisine". It is intended for a variety of underwater scavengers, from crabs to hemits, lobsters and even crawfish. I read the fine print on the label tonight; the first ingredient is fish meal, but from there it goes on to corn, rice, wheat, and soybeans, and only then, krill and fish oil. Next, there's garlic (just in case I might want to eat my hermits?), yeast, and a long list of vitamins and minerals.

It must be good for them; they're healthy and happy. But - corn? And garlic?

Shrimp with a corn and fish pellet. Yum!

I also have dried shrimp, and when I can find them, frozen raw shrimp; everybody loves those, but they disintegrate and pollute the water, so I feed them sparingly. And there are "shrimp pellets"; the primary ingredient in these is ... wheat.

At least there's no high fructose corn syrup in there. And I'm glad that I supplement their diet with seaweeds and, in season, hydroids.

Good appetites. No table manners.

It was supper time in the tank, and I had pulled up a chair to watch the action. The hermits and crabs were chasing each other around, trying to grab a juicier shrimp pellet; yours is always tastier than mine is the rule. Hermits were raining down from the eelgrass; it's quicker just to let go and drop, and half the food was already in play.

The crabs, being bigger, bowled over a hermit or two, yanked the pellets out of their pincers, and scuttled away to eat in hiding. They're keeping everything, even the leftovers, for their own selves. "What We Have We Keep".

Val, the big burrowing anemone, had caught her share, but now hermits were crawling through her tentacles, gobbling everything they could reach, and she was folding in on herself, trying to swallow before all her meal had been stolen.

The Nassa snails were bustling here and there, siphons high, following the scent of shrimp in the current, always arriving too late; the pellets kept sprouting legs and racing away. No matter; they'd get the crumbs later on. So will the little orange striped green anemones scattered everywhere, waving open tentacles.

Tiny polychaete worms living in the kelp holdfast were hungry, too, and poking around looking for fragments. One, about the thickness of a fine pencil lead, even dared to snatch a pellet from a hermit's pincers, repeatedly. The hermit fought him off, more angrily with each attempt, until I reached in and brushed her away from the holdfast to prevent mayhem.

The bubble shells were the only ones not interested in food, apparently. They were stacked up in a pile, three-deep, mating. As usual. Later, they would lay another batch of eggs high up on the wall.

At my end of the tank, a wandering worm poked his face out of the sand right by the glass. The ones in the holdfast are a dull red; this was one of the blue and pink ones. But such a blue! And such tiny pink toesies!

He's about 2 inches long.

He slid one way, waved his head about, as if sniffing, pulled back, tried again, pulled back, went the other way, stretching out and out, so slowly, cautiously. "Sniff, sniff ... I smell shrimp! Where is it?"

The best view I've had of those feet, so far.

Zooming in. Three "toes", a couple of spines, and an orange brush on each "foot".

He gave up. The shrimp pellets had all been captured. He pulled himself back down into the sand. A while later, I saw him ease out of the sand deeper into the tank, still sniffing, still hungry.

A gourmet treat for my little ones

I brought home a handful of seaweeds for the hermit crabs, planted the eelgrass in the sand at the bottom of the aquarium, and left these brown weeds floating near the surface. Within minutes, half a dozen small critters had climbed up to graze.

While I was checking them, I noticed the hydroids, standing like little fans all around the stalks and the float bladders.

These are tiny; the bladders measure about 3 mm. lengthwise.

I took a quick photo, one only because I had to leave. When I looked at it later, I decided to take my time and get a good shot. I went back to the tank, and found bare stalks. The hermits had eaten the hydroids, every single one.

Gotta be quick around here!

Feeding time in the tank

My aquarium "how-to" bookshelf holds only three books, which I re-read frequently, and which all give conflicting information. Living things are like that; almost any rule about dealing with it has exceptions. So I read a chapter in one book, the related chapter in another, then go commune with my critters. They have their own ideas.

The books:

• The Conscientious Marine Aquarist. 1998. Very good, very detailed, well written. Most of it is not relevant to what I'm doing, though; the author's interest lies in the tropics, and the exotic species, whether or not they live together in the wild.
• The Saltwater Aquarium Handbook. 1991, 2000 edition. Much smaller. Good info on equipment, skimpy on invertebrates. Emphasis on purchased specimens, warm water animals, exotics.
• And the Marine Aquarium Guide. DeGraaf, 1973. Out of print. Dense. Very technical; a lot of chemistry and detailed engineering. A variety of methods and their explanation; choose your own. Extremely helpful, even though I followed none of the methods described; at least I know what to aim at, what to watch for.

And of course, there is plenty of information, usually contradictory, on the web. Reef aquarists forums are helpful. Here's a sampling:

• Reefkeeping - a magazine. The current issue has a good bit of info on adjusting water quality.
• Aquarium Advice. A useful forum.
• Reefs.org. A forum and a magazine.

And then, there's the local aquarium store. Which usually doesn't carry what I've seen discussions of, and I have to wing it. Still, they sold me my tank and filters, and 20 kilos of sea salt for aquariums; that's what has kept my critters happy this winter. And they sold me the hermit food.

Hairy hermit, with his breakfast of Crab Cuisine.

So, what do my guests order from the menu?

The hermits love the Crab Cuisine, even though it was not specifically designed for underwater hermits. It sinks nicely to the bottom, but after a bit of nibbling, it tends to crumble and float away. Val, the burrowing anemone, grabs pieces that float by, but eats them slowly. After a while, the hermits, having finished their serving, go prospecting in the anemone mouth for leftovers, which the anemone yields up without a whimper.

The crab (I only have one at the moment) can't do this. He loves the CC. He grabs a piece and runs off to hide in his latest burrow to eat in peace. Later, he may approach the anemone, but the venomous tentacles drive him off, and he gets to sit looking at that tempting chunk of food until a hermit walks in and takes it, right under his nose.

In a Chinese grocery store, I bought a bag of dried minnows, intended for human consumption. Nothing but fish and salt, the label said; it would be safe. I flake a half minnow into the water now and then; everybody is pleased: the crab, the hermit, the anemones, and any polychaete worms hiding in the sand. It does foul the water, though, so I like to offer it just before a water change.

Another Chinese food store, recently: I found a bag of dried shrimp, very tiny baby shrimp. Opening the bag at home, I realized that they were only partially dried, and still soft, so they're in the freezer. And this is dessert! As I drop a piece in front of one hermit, all the animals with legs start running in his direction. Fights break out, unusual in hermits. The largest grainy hand, the absolute pacifist, even attacked my finger. The crab abandons his hiding place to grab at the shrimp, and the hermits fight back. I drop more tiny pieces, a quarter shrimp at a time, scattered around, to break up the fights.

Some of the hermits take their prize and climb to the top of the eelgrass or a stalk from a kelp holdfast, where no-one can sneak up on them. Others just stand their ground, tugging away at another hermit's catch.

Nassa, hurrying.

And a minute later, the Nassa snails appear, as if from nowhere, heading purposefully towards the biggest chunk of shrimp. They will stay with it until there's nothing left.

Val, on a normal day. (No shrimp.)

What of the anemone? The books say (two of them) to offer a small piece of shrimp, touching the tentacles with it. Another book says to blend the shrimp, turn off the pump, and spray the anemone with the shrimp paste. I didn't get around to that, because an entire shrimp escaped my fingers in the tank, and floated past the burrowing anemone. Instantly, a tentacle lashed out, snared the shrimp, and crammed it into her mouth. The whole shrimp. And it vanished.

Val swelled up to her full size, column as high and as wide as I've ever seen it, tentacles waving enthusiastically. (Did you ever see an enthusiastic anemone? I have.)

I've fed the tiny orange striped anemones baby-sized bites. They're slower to grab the food, but when they do, they don't let go.

Val really doesn't need feeding. She manages quite well on her own. I saw her snatch a swimming amphipod.  And recently the crab molted. The old molt floated by, and Val grabbed it. It was wider than she is, and all legs and carapace. Never mind, she swallowed it, slowly, one leg at a time. The next day, she regurgitated the polished carcase.

And she had positioned herself under the pump. I didn't notice, but a fair-sized periwinkle snail was on the side, and when I went to remove the pump for cleaning, the snail let go and dropped. Right into Val's mouth. I quickly got my handy chopstick and tried to flick the snail out; no way! She closed right down, tight, a green ball with a pursed mouth, and the snail hidden away inside. Sorry, little snail.

The next afternoon, one of the hermits was wearing the newly cleaned periwinkle shell. Life goes on.