Showing posts with label disaster. Show all posts
Showing posts with label disaster. Show all posts

Monday, February 18, 2019

Disaster averted

I don't post very many photos of my aquarium critters these days. It's not a lack of interesting things going on, but most of them don't show up in photos. And have been discouraging, as well.

I've been collecting fresh seawater for the tank every couple of weeks. Until this spring, the best access point (with my heavy 5-gallon buckets) was at a local boat launch, where I had a platform to stand on over water deep enough. Then the city decided to "improve" it. First, it was blocked off with fences, then the heavy machinery came in and played in the mud all summer. I found another access point, a few miles down the road, which worked fine until the winter storms blocked it with logs, and a sign went up, saying that the logs would remain until spring.

Okay. I went back to the old boat launch, that was now open. Very nice: two long piers out into the water, anchored with a post at each end, a clean cement ramp leading down, as opposed to the slippery, uneven slope I stumbled over last year. Very nice. I filled my buckets easily and took them home.

And almost killed my whole tank. As soon as I changed the water, all the anemones shut down immediately. The big brown plumose anemones started sending out her distress symbols: acontia - long white threads streaming out from her body. The crabs and hermits sat still, looking sleepy; they were not interested in food.

"Metty" in a bad mood. Photo from 2015.

But everything looked good! The tank had been scrubbed, the water was clear, the pump and bubbler were going strong. I gave them a few hours to recover, and looked again. Worse. Some of the anemones on the walls had just given up and were mere smears on the glass. "Metty" was an angry brown disk. The crabs were barely moving.

I checked the water. The salinity was 'way down, the acid level 'way up. I corrected these with salt and bicarbonate, added water conditioner. That should have fixed it.

But where did the salt go, and where did the acid come from? The nice, fresh, clean, but still uncured, cement works at the boat launch, maybe? And did the "improvements" include re-routing a stream into the launch site? With fresh water, and possibly lawn and business run-off? What other poisons came along with that cool, clear water?

When, two days later, none of the anemones seemed to be recovering, and no-one had any appetite, I went for water again. This time, to a beach where I had to wade into the surf, then haul my buckets over logs and rocks and slippery sand and a lawn to reach the car. (A man passing by saw my struggles and came to help; much appreciated!)

I changed the water again. The crabs woke up. The hermits discovered their appetites. And slowly, so slowly, the anemones took in water, opened cautious mouths, waved tentative tentacles. My largest pink-tipped green anemone - so beautiful she had been! - had broken down into three or four brownish chunks and fallen to the bottom of the tank. Two of the chunks now anchored themselves to shells and looked about for food.

Today, a month later, they're still cautious. But the pink-tipped anemone is finally pink-tipped again. And the crabs and hermits are enthusiastically pairing up; I have two pregnant crabs.

And spring is coming. And the logs will be gone. And - I hope - no-one will try to "improve" the second boat launch.

"Hi, there!" Waving female crab. She may be newly in berry.



Friday, September 08, 2017

If wishes were horses*

It's raining. My geraniums are blooming.

So red!

And I feel vaguely guilty over feeling happy for the coolness and the clearing air, and over my annoyance at finding muddy cat footprints across my desk, while wildfires rage up and down the west, hurricanes play tag in the Atlantic, a major earthquake shakes Mexico, floods drown South Asia, with malaria and dengue fever following in their tracks, the Koreas prepare for war ...

"Stay safe, everybody!" doesn't cut it. I am so sorry.

*"If wishes ..."

Friday, November 28, 2014

Underwater epidemic

Or, The rotten egg zone, Part II
(Part I, yesterday)

The bad news first.

The starfish are dying.* Up and down our coast, from California to BC, millions of starfish and sunstars are curling up as if in agonies, losing arms, and then quickly dying. The cute little brittle stars are infected; sea cucumbers are spilling their guts and rotting. No-one seems to know precisely why.
Affected sea stars typically first contort and twist, and white lesions appear on their bodies. Their usually firm, meaty bodies deflate and waste away. Arms fall off and walk off on their own. The animal loses its ability to hold on to rocks or pilings. Its body falls apart in pieces, and finally dissolves. Within weeks, only a ghostly white print will remain, and then nothing at all. Entire communities are wiped out, as if they never existed, (SeattleTimes)

(Stories, USAToday, SeattleTimesPBS.)

One of the scientists trying to find out what's happening, and why, is diving photographer Jan Kocian, co-author of a Reef2Rainforest blog. I found an article there, about a series of dives in Puget Sound, off Whidbey Island, just a short distance south of here,

. . . with the objective of obtaining photographic evidence of, particularly, the sea-star wasting disease epidemic . . .

He discovered masses of dead and dying brittle stars. It's a gruesome read, and the photos are frightening, but if you can stomach it, it's worth the effort.

Here's the gist of it, though: Kocian made a series of visits this September, finding sick sea stars, then dead sea stars, dead clams, dead and dying sunfish, dead sea cucumbers, dying sea urchins, worms, and more. By the end of the month, some areas seemed to be recovering after a storm which cleared the water, but further off-shore, the carnage continued.

The full extent of the dead area, and the reason for the mortality, remain indeterminate. Typically in Puget Sound, the benthos is very rich, so that a mortality event such as this may take several months for even partial recovery.  Although the substrate will appear to recover in a few months, quantitative sampling will show the benthos make take two or more years before it has returned to normal.

Many scientists studying this believe that it may have something to do with the increased temperature of the water; even a portion of a degree, on average, can have a major effect, stressing the animals and promoting the growth of bacteria. (I read on another website that some sea stars recovered when the temperature dropped.) Or it could be a bacterial infection, an underwater epidemic. Or ...

The cause could be a toxins, a virus, bacteria, manmade chemicals, ocean acidification, wastewater discharge or warming oceans. "We're not ruling anything out," Raimondi said. (USAToday)

I've found a few dead starfish on the beach at Boundary Bay recently, but they had all their arms, and their deaths were probably, I hope, due to more usual causes. And the stars that came home with me a few weeks ago seemed healthy. I keep hoping.

Ok. Now the good news.

After reading all this, I examined my three mottled sea stars carefully. They look fine. They're eating and growing and making a general nuisance of themselves. I don't see any early lesions, but I'm making sure to keep them cold and change their water frequently.

And I found the answer to a question I've been asking. As Ron Shimek, Kocian's colleague writes,

As is often the case in a study such as this, serendipity will rear its head, and wholly unexpected observations will be made.

And I'll leave my discovery for tomorrow.

Sunday, February 19, 2012

Between the grains of sand

With a good microscope handy, I've been able to look more closely at what's happening on the White Rock beach. Last Tuesday, I brought home a few small containers of sand and water from the contaminated area. I've been examining them to see what's alive, down there between the sand grains.

Wet sand, as my camera sees it. The little orange specks are alive.

I've been taking notes, mostly sketches of what I see, and I've scanned a few pages. I can't identify any of these things, but they give an idea of what's there. Everything I drew was alive and moving. A couple of times, a humongous (or so it seemed) copepod scooted by, at least 10 times the size of the biggest of these critters. The copepod would be about 1 to 2 mm. long.

The images may be pale; I find them easier to see by clicking to get a full-size photo.

Page 1. "Hamburger critters" like a split bun with something in between, boxes and pen-like things.

The ones labelled "1" and several similar ones don't quite match each other, but may be different stages of the same animals. # 5 is like them, but was the largest I saw. In the center, I could see something fluttering. They all swim slowly, along the length-wise axis. The "pens", # 4 and three similar ones, moved only their tips as long as I watched.

Assorted swimmers and jittery stuff.

#6 looks like a piece of threaded pipe. All the ones I saw were the same size. #8 is sort of like an amphipod, but extremely jumpy and hard to see, even though it was large. The antennae/legs/hair moved constantly.

#9 is one of the strangest animals. These are very tiny, like a balloon on a black thread. The top constantly bobs back and forth, always in the same direction.

And #10 is like a hairy flatworm, always changing shape; it has no features that I could distinguish.

Worm?

This was another of the larger animals. It lay against one of the sand grains, moving along sluggishly. Occasionally, something would startle it, and it contracted instantly into a collapsed balloon shape. A minute later, it stretched out again. I'm not sure if I saw tentacles at the forward end, or if they were a trick of the light.

Movers and shakers.

These were the weirdest of all. #13: a blob with a smaller blobby end. It turned around and around, circling about the narrow "head" end, as if it were attached. To what? It was in an empty space between widely-spaced grains.

#14 is tiny. I only saw the one. A rough pyramid, with a tentacle that I could see inside the body as well as out. It traveled with the tentacle in the lead.

#15. A tubeworm? Long and snaky, it hid behind a sand grain, extending the tip. Closed, it looked like a worm head, but it kept opening wide, showing a circular mouth. From time to time, it suddenly extended itself its full length again, as if to capture something.

#16. I can't figure this one out. A dark oval shape that spins and spins, always in the same direction, very rapidly. I could barely see the connection, but a tiny blob spun with it, sometimes close, sometimes a distance away, but always coming back as if tethered.

#17 looks like a baby sand dollar. #18, like a jellyfish. Many different animals start life as a medusa, a jellyfish shape; this could be any of them.

Besides all these and the copepods, I saw a few larger worms slithering about.

All this is good news: there's life down there. Two of the containers held sand and water from about 100 feet down the beach from the center of the dead zone; they were full of those "hamburger" critters, and others. But the two bottles from the center were basically empty; nothing but sand grains and a tiny worm.

Elva Paulson asked how big the dead zone is. I checked again, on Google maps. From where we access the beach, moving west, we went, the first time, 300 feet before I found anything alive. The next time I measured, the zone had extended and the borderline was 1700 feet down the beach; about 1/2 kilometer.

Tuesday, we began to find beach hoppers and tiny snails somewhere between those two distances. And the first bottles of sand I collected were well within the former dead zone, about 100 feet from the access.

Looking at the satellite photo, I notice that a creek comes down from the top of the hill, just there. I wonder if there's another construction project up top.

Saturday, October 01, 2011

Recovery, Part three

One advantage to having many mouthparts, like a crab does, is that they can substitute for hands. So when my poisoned shore crab lost both of his pincers, he didn't have to go on a diet, just because he couldn't pick up his food. Instead, he bent down to the ground to grab things with two big, flat paddles, the third maxillipeds. The second maxillipeds (read "jaw feet") have hooks on the ends; between hooks and paddles, he could cut and tear a salad of sea lettuce, or mash a fish filet. And he still had lots of machinery behind those, for chewing; another pair of maxillipeds, two pair of maxillae (jaws), and a pair of mandibles. No problem.

It did worry me when he molted, and promptly lost his replacement pincers and a pair of legs, too. This is a fairly common reaction to stress, called autotomy; the crab amputates his own limbs, usually just one of the pincers. Two pincers and two legs was a sign that Mr. Crab was at the end of his resources.

Once the tank was completely cleaned out, he seemed happy enough. He didn't lose any more pieces. I made sure to feed him well, putting treats down right in front of him, and turning off the water pump until he'd finished eating.

That was in July. In August, I noticed a tiny bud where one pincer had broken off. He had started the process of regeneration. In mid-September, two pincers were well on their way.

Six-legged crab, with pincer buds. Inside the translucent covering, the developing claws are visible.

Yesterday morning, he molted again. And now he has two pincers, and all eight legs.

The pincers are smaller than the originals that he lost. Next molt should fix that.

The molted shell, showing the buds where the pincers grew.

When he backed out of his old shell, his skin was soft and pliable. He pumped his body full of water to expand the tissues before the shell hardened, leaving him room to grow. The new pincers expanded like balloons, so they are many times the size of the buds they came out of.

The tank looks healthy now; the amphipods are multiplying again, and three tiny hairy hermits are scrambling about happily. I think Mr. Crab will be able to keep those shiny, new pincers this time. It's been almost 48 hours now, and he's still intact.

And the thermometer at the window read 60° F. this evening. The long summer is finally over.


Thursday, September 29, 2011

Slow recovery, part one

It's been three months since the miniature oil spill that killed most of the animals in my aquarium. A long, hot, difficult three months.

For those that didn't see the original post, here's the story, in brief: air-borne pollution from a construction site next door covered the water, first in my outdoor seaweed bowl, and then in my marine invertebrates aquarium inside, under an open window. Most of the animals died that first week, leaving me with a few crabs and snails, two brain-damaged shrimp and a handful of sick hermits; these last all died by the second week.

The green shore crabs survived, but not without side effects; one big male lost both pincers, the day after he'd molted. The invasive mud snails were fine, as were the little predatory nassas and most of the barnacles. And my big wandering plumose anemone opened for business again.

Community pre-disaster. Small anemones, snails, barnacles and an amphipod.

Since then, I've been silent, at least as far as aquarium blogging goes. I could have tossed the whole thing and started over, putting my few animals into a fresh tank, but I wanted to learn what goes into a recovery in the wild. And just as it is in the ocean, where oil spills take years to clean up, healing my small tank became a long, slow process, with tiny improvements and discouraging setbacks.

The first imperative was to clean the water. This is easier in a small aquarium than in the ocean, of course. A few water changes, each time replacing half the water and cleaning the filter, should have been enough. The tank looked clean, and the crabs and snails went about their business cheerfully. But any animal that came along for the ride in fresh seaweed died in the first few days. I scrubbed the walls of the tank and changed the water again, to no effect.

Female shore crab, pre-disaster.

The maimed crab molted. With the fresh molt, he had regenerated his pincers; they were smaller, less powerful than the originals, but he looked good.

And the very next day, when I fed him, he showed up with no pincers and missing two legs. The smallest of the crabs molted, as well, and lost a pincer the next day. Something was wrong.

One of the last photos of my grainy hand hermit, before the tank was poisoned.

This time, I emptied the tank, scrubbed the walls, and removed the deep sand from the bottom. Once it was out of the water, I could smell it; a rank, chemical smell. There were no small animals alive in it, as there normally are. I dumped the whole lot, and set up the tank with only a dusting of clean, broken shells underfoot.*

All but one of the tiny anemones were gone, but the big one was still there, although she** spent most of her days closed in and hunkered down into a flat plate on the glass. To clean the glass properly, I would have to convince her to move.

Some species of hermits encourage anemones to attach themselves to the hermit's shell, boosting the hermit's weaponry and camouflage. The hermit nudges at the base of the anemone until it detaches from its chosen site, then he holds her gently against his shell until she glues herself down there.

I imitated a hermit. I pushed softly at the base of the anemone with the back of a fingernail. After a while, she let go and drifted to the bottom. I collected her and put her in a plastic bowl to wait until the tank was fresh and clean. When all was ready, I leaned on her again, then moved her back into the tank, down on the bottom with the clean shells. She attached herself, and after a bit of sulking, opened up to feed again. At least something was working!

Small snail, today, eating algae off the glass. The pink circle is the mouth, with the scraping radula.

So that was done. After a couple of weeks with no more deaths, I added a few handfuls of pebbles to the bottom, and began to bring in new snails and amphipods; the snails to keep the algae down, the amphipods to feed the anemone. Things looked good, and I brought home a bag of sand; the crabs and snails dug in happily within minutes. The amphipods started to breed.

Amphipods love these crevices in an old barnacle shell.

But there are other pollutants. Our problems weren't over. The anemone's story continues tomorrow.

*It's a pity we can't do that in the ocean.
** These anemones start out as males, and become females later on. I assume this one is old enough to be a "she".


Monday, September 26, 2011

Survivor

Anemone and bubbles:


I've been sorting old photos: this is from last January. The anemone survived my tank disaster, one of very few critters that made it. What it has taught me since then will be tomorrow's post.

Saturday, July 02, 2011

Small disaster!

A foretaste of things to come, in miniature. Story tomorrow; I'm too disheartened at the moment to write.

Wednesday, May 05, 2010

Invisible dancers

I brought home a few egg coils on eelgrass and seaweed recently. I haven't been able to identify them, neither in reference books nor on the web. So I've been keeping them in two jars of seawater, observing them daily, to see what hatches.

Last night, in one I detected a hint of movement through my lens. In the microscope, I saw the first of the larval forms swimming or gliding about.

Besides these, though, at 200x power, we saw hundreds of tiny spots dashing about, twirling, zig-zagging; always in rapid motion. The screen looked like one of those old TVs with "snow". (Remember that?)

I tested water, a couple of eyedroppers-full from my aquarium, my aerating tank, and both jars of eggs. In all of them, these teeny spots sped around the screen.


Screen shot of a drop of "egg water". Everything there is moving.

This afternoon, I read this, in an article about the oil spill, by William Dietrich:

"Second, cleaning up oil once it escapes its confinement remains an almost impossible task. The technology was not very effective in Alaska, and so far it does not seem very effective in the Gulf. In Alaska, the oil industry tried chemical dispersants such as are being used in the Gulf, booms, burning, hot-water pressure washing of beaches, bio-remediation by culturing bacteria to eat oil, and even wiping rocks with rags. None worked very well. After humans quit, winter storms finally broke up and eroded the surface oil, while subsurface oil still lingers.
Once wind pushes the oil into mangroves and estuaries, forget about it. The damage is hard to imagine until you see it. But to get an idea, dump a quart of dirty motor oil on your driveway and try to clean it up.
There will be immediate photogenic bird kills, but then a much longer and more insidious presence of oily contaminants in Gulf ecosystems. The real damage will play out over years, not days."

He writes, "... photogenic bird kills". The tiny things are not photogenic. We don't even know they are there, but they are the base of the food chain on which everything depends, even us.

I imagined oil creeping onto our beaches, killing the birds, the fish, the crabs, the beach hoppers and amphipods, the snails, the copepods, the assorted larvae, and all these trillions of water dancers. I feel sick.

(Yes, I promised stuck-up spiders. I got sidetracked. They're next.)
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