A sad post

I've been putting off writing this post, procrastinating in the futile hope that it will go away. It never works, does it?

November 26, three weeks ago: In the aftermath of the storm system that blew over most of BC, we went down to White Rock beach to see what had blown in. Just logs and broken plastic, it seemed. I wrote about it here.

I collected some fresh seawater for my critters in the tank at home; only about one litre, since I'd forgotten my regular 2 litre bottle. The water was dirty, with bits of eelgrass, wood chips, sand and muck, all whipped up by the crashing waves. It didn't matter; at home, as I have done before, I filtered it well, then let it sit for a few days for the fine silt to settle out.

The next week, as usual, I replaced 2 l. of the old water in the tank with new, including the latest beach collection.

All seemed well for a day or two. Then one morning, I noticed that my female crab was having difficulties. She stood on her head, with the hind legs swaying in the water, spread out. It took her a long time to right herself, but then she seemed ok. Until the next time I checked on her, when I found her caught upside-down in some seaweed. Something was wrong. (And she was in berry after their recent mating!)

The other two crabs seemed fine. But the big anemone was writhing and contracting oddly, making himself into a series of balls, then flat, then one ball with a pin-head tip, then a wide tip balanced on a pointed base, never opening tentacles to feed. A smaller anemone had disappeared entirely; so had the eelgrass isopods. I couldn't see any limpets, nor any pairs of amphipods waiting to mate. And the snails, those indestructible nasas and mud snails, were lying about, half out of their shells.

I hurried to change as much of the water as I could for freshly-prepared artificial seawater, adjusted for just-right salinity and temperature.

The next day, the anemone was worse; only a few snails were moving. Three clams were holding their siphons well out of the sand, about an inch high. I've never seen them do that before. And the big male crab was lying paralyzed, with legs stretched out and up, towards the back. The female was upside-down more often than not. The little male had disappeared.

I did what I could; removed everything to a "hospital" container with fresh water and clean stones, twice; watched and hoped. For a while, it looked as though the male would recover, but no, he relapsed. The snails died.

When the little male (that I had raised from crab babyhood) floated belly-up, too, I gave up. I drained off the water and replaced it with alcohol. They died quickly.

The baby, with anemone, in happier days.

What had happened? I have gone over and over each step of those days; the only source of whatever killed my tank would have been the water from the White Rock beach, where I have always collected water. And the only difference there would have been the after-effects of the storm. Was it contaminated rainwater from the city on the hill above the beach? Or something brought in by the wind and waves? I don't know.

(My previous die-off, not as complete, was caused by local pollution, blown in from next door. There was no sign of that this time, and the symptoms and species attacked were different.)

We have seen, on occasion, areas of the beaches we visit where large numbers of dead animals lie half-buried in the sand. (May, 2008, baby sand dollars, for example.) There are spots where dying clams lie thick on stinking mud; patches where we find no live animals at all, no matter how many rocks I flip, or how much sand I filter through. Sure, the areas recover, often, at least in part. Or become hosts to new forms of life, like the invasive mud snails that now cover much of the Boundary Bay beach on the Tsawwassen side. Sometimes they don't; years ago, Mom used to tell me of a beach on Vancouver Island where she could not find anything alive. It seemed impossible, back then; now not so much.

I have emptied and cleaned the tank and all the equipment, and hidden them away. I moved the furniture around so that the gap where they were doesn't show. I dumped everything previously alive in the garbage; I would normally bury it in the garden, as fertilizer, but I can't take the risk of poisoning the many animals that live in my soil. The sand will be spread, well washed first, in the most gravelly, polluted area of the vacant lot.

In the spring, I'll probably have the courage to start again. For now, I'm grieving.

I originally started bringing home beach invertebrates to learn something from them. More than just how to identify them, I wanted to know how they lived, how they interacted with other animals. I was even privileged to learn something about how they think, to see them show a reciprocal curiosity, watching me through the glass, responding to what I was doing. What kills them, how they suffer and die (that anemone's tortured contortions still break my heart!) is also something I have unhappily begun to learn.

It has made me very aware of what I buy, what I use and discard; it all enters the environment; it has the potential to do much damage. We can't turn back the clock; we've fouled our nest already, but at least I can keep from adding more poison to it.

An end and a beginning

Here's an update on the aquarium situation:

The three remaining hermits have died. I replaced about half the water, again, this time with an emergency mix (bottled water and sea salt), and then Sunday afternoon, with freshly collected water from Boundary Bay. The shrimps and crabs seem almost back to normal, and the anemones are tentatively opening up again.

I am grateful for the concern people have shown, and for your understanding of the analogy I presented. The life and death of a few miniature hermit crabs and amphipods seems such a small thing, almost not worth wasting time on, much less grieving over (as I have done), but it's like a trickle of sand down a steep mountainside warning us: watch out for landslides! Stop digging at the bottom!

I have been wondering what to do now. I have an almost empty aquarium. I could return the snails to their beach, with no difficulty. But I feel that I have a responsibility to my maimed crab and brain-damaged shrimps. They would not survive the challenges of the wild for very long. So I must keep the aquarium going.

On the other hand, I don't dare import more critters until the construction next door is finished. I've been thinking, though, that I've been so entertained by the more active residents that I've almost completely ignored the plodding workhorses, the snails that aerate the sand and clean the algae off the glass. Maybe this is an opportunity to learn something more about them. So for starters, meet Sir Molasses.

What's not to love about that face*?

* Well, not exactly a face; the "eyes" you see and the "whiskers" are mouth and neck features. We're looking into his mouth. I've started on a video; watching a snail eat turns out to be surprising.

Extinction event, in microcosm*

It's been a little more than two years since I started my "beach critter" aquarium. I've tried to make it as home-like as possible for the animals I brought home, within the limitations of a constant water level, and limited space. They're possibly a bit safer, since I keep a close eye on predatory species and there are no interruptions in the food supply. My aim has always been to learn more about the beach environment and its residents; to recognize their individuality; to learn their habits and needs, their loves and hates. (Yes, they have those!)

Now I've learned something more, something I'd rather not have. Disaster has struck.

I should have seen it coming. Maybe I did, at some level; the last couple of weeks I've been aware that something was "off", but I couldn't put my finger on it. We reached the tipping point a couple of days ago, and then it was too late to stop the slaughter.

It's a longish story; let me go back to the point where the tank was a happy place, not all that long ago. It was full of varied life, all finding their own niches, interacting with their neighbours, teasing one another (the only way I can describe how the shrimps bounce on the crabs' carapaces, tickling their eyestalks, then dancing away when the crabs react), sometimes squabbling, sometimes co-operating. Snails tunneled through the sand or climbed the walls. Four shore crabs and a baker's dozen of hermit crabs scrambled over them or carried them on their shells. The anemones fished for bits of food; so did many barnacles. Deep in the sand, a few clams and a mid-sized polychaete worm burrowed. Too many amphipods to count swam back and forth, or hid in the sea lettuce. There were four eelgrass isopods, with eelgrass to keep them happy, tiny, brown-and-white limpets, mussels and tubeworms.

It's all gone.

I always kept a bowl of clean water with a few handfuls of sea lettuce and maybe some eelgrass, for when the crabs had eaten holes in the veggies in the tank. A hungry flatworm had been exiled there, with a snail or two, some barnacles and mussels, for prey. The bowl sat outside, in the shade. A couple of weeks ago, when I went to add fresh veggies and a change of water, I found a scum on top of the bowl. Dust in the air, I thought, and cleaned the bowl thoroughly.

(This next seemed unrelated at the time, but now I know better. The small church next door has started on a major construction project. Rather than the wood and metal of our local housing, this building uses huge, curved structures of pre-formed concrete, about three stories high. They've been working on it for about two months.

A few days ago, I walked around that side of our building, taking yard waste to the collection area. As I passed the construction, I almost choked on something wafting from it; it smelled like a combination of industrial-strength cleaner, paint thinner and maybe vinegar. I warned Laurie away, but he was already complaining about not being able to breathe. Our troubles, easily remedied by going somewhere else.)

In the aquarium, some of my critters had gone missing. I cleaned the sand, as usual, a week ago, and didn't find the polychaete. There were only eight hermits and three crabs; where were the rest? The clams had died, and the crabs had cleaned out their shells.

There was more scum on the bowl of seaweed; I drained it, and washed everything well, then put in fresh saltwater. The flatworm was gone, and there were a couple of sickly-looking polychaetes hanging out on top of the sand.

I think it was about then that I started to realize something had gone wrong.

Two days later, the scum was back, thick and oily this time. The water stunk of chemicals. The seaweed was caked with scum and I threw it out, as well as the dead polychaetes, then, with nothing left but sand and smelly water, I dumped the whole lot.

The next evening, the 29th of June, the water in the aquarium was milky and the filter pump was labouring. I could only find five hermit crabs. I took everything out and cleaned the tank and filter again. One of the crabs had molted; all well and good.

The first of July, Canada Day, was a good day. My son came to visit with his family, and later we went for a walk in the cool of the evening and met an old friend on the street. We came home to water the garden before dark. So far, so good, but after that, I checked the aquarium. The crab that molted the day before had lost both big pincers; they were floating up against the glass. Why? And the tank looked empty; there were no amphipods visible, and the anemones had contracted themselves into little plates against the glass.

When I emptied the tank again, I found three healthy hermit crabs, one dying, and one looking sick. The coonstripe shrimp were behaving oddly; trying to swim but being swept away by the current, or failing to achieve lift-off. I could smell just a whiff of that chemical smell in the water of the tank; I changed half of it, with all the fresh sea-water I had on hand.

I counted my critters: surviving were the hermits, about half a dozen amphipods (of hundreds!), most of the barnacles and mussels, the two sick shrimps, and the three crabs, including the clawless one. Looking closely at the hermits, I realized that two of them, the sick ones, had also discarded appendages; a couple of legs by one, and a pincer and a leg by the other. In the morning, those two were dead, and another looks sick now.

The snails are fine, so far. The invasive Asian mud snails seem to have multiplied; I counted about 30. The little nassas plow around as if nothing were the matter. A few periwinkles are left, but they leave the water to rest at the top of the aquarium.

Dying greenmark hermit, upside down in a "hospital" bowl. He only has three legs left at this time; a bit later, he will lose another. He can't right himself, nor walk when I set him upright.

1. I've been thinking that this is a foretaste of what will happen to our oceans as we continue to pollute our air and water.** I don't see that we are going to stop, either; not until it is far too late. I'm remembering the oilspill from last year; so many dying birds, so many dead animals. And what of the amphipods, the crabs, the beautiful anemones, the jellies and sea urchins, the shrimp, the cheerful hermits! I feel sick.
2. I think it is possible that their resistance to poisoning may be a factor in the current glut of invasive mud snails on our beaches. And, since they concentrate pollutants*** in their tissues, would they also be a factor in the reduced number of shorebirds that we see?
3. If so, maybe all life in the seas will not die out. There will always be something that can adapt, some critters that can go on as if nothing had changed. But will our shores be like my tank, now; clean sand, drowsy snails and a few hidden crabs? Nothing else?
4. As I said, I feel sick.

* Microcosm: From http://www.thefreedictionary.com/microcosm

A small, representative system having analogies to a larger system in constitution, configuration, or development:

** I found this in the morning, while I mourned my dead hermits. http://www.physorg.com/news/2011-06-scientists-massive-ocean-extinctions.html.

*** From http://www.brighthub.com/environment/science-environmental/articles/13705.aspx:

Other organisms are highly tolerant to pollution of their environments, among these are aquatic worms, leeches, and snails. As a rule, as complexity increases, tolerance to pollution decreases. Keep in mind that, even though these species may be able to survive in less than ideal environments, the species that rely on them for food may not be able to. Further, any pollutants or toxins in the prey animals or plants will be concentrated in the predators unless their systems are capable of removing the compound from their system.

Update: Another relevant article. http://www.canadaeast.com/rss/article/1420451

...the vast, empty expanses of our dying oceans.