Empty beach

Saratoga Beach, Christmas day; a rare moment when all the groups of walkers were behind me.

Fine, white sand (viewed under a light). And fine, new, white snow on the distant mountains.

Something very strange; I collected a good handful of sand from the very edge of the water, well below the upper intertidal limit. I took it home in a plastic bag, poured it into a tray and watched it under a lens, and then my hand microscope. Usually, within minutes I can see signs of activity; a grain of sand tumbling as a worm thrashes underneath it, a minute snail making his slow way among the "rocks", a string of copepods chasing each other through the ravines.

There was nothing happening here. Not the least hint of vibration. No corner-of-my-eye flashes, gone before I turned my attention that way. Viewed from an angle, no mini-bubbles.

I left the tray overnight, and then over the whole day, giving worms time to build their tubes to the surface. Nothing happened. I looked again, just now. There's nothing there but glassy sand grains and water. Not even remains of sea creatures, broken shells and bits of crab molt. Nothing but sand.

I have never seen anything similar, except in sun-baked sand found on top of logs. There should be something alive there!

Granted, my microscope only goes to 40x, so with a more powerful machine, I could probably find bacteria and diatoms. But it is still curious; there should be hundreds of worms in there, at least!

I must make a return trip, collect more sand, from different spots.

(I flipped a few stones on that spit in the distance. No crabs, no snails. I did find some barnacles.)

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, SeattleTimes, PBS.)

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.

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.

Hope on the rocks

Last November, I poured fresh seawater from the White Rock beach into my aquarium, and the aquarium died. (A sad post) A month later, we returned to the beach. I searched for live animals, and found that a large section of the beach was dead. (Empty beach)

Since then, I've been flipping stones every time we visit, with discouraging results. The dead zone increased, and I correlated the boundaries with the areas where several large homes are being built up on the cliffs above. It may be that run-off from their work is causing the damage: it may just be a coincidence.

When the tide drops, we walk over the stones covered with barnacles. Dead barnacles, these days; empty shells, for the most part. There is no greenery, except for bits of rockweed. Under the most likely stones, I have been finding the occasional group of immature shore crabs, sometimes a polychaete. Recently, I've seen the amphipods skidding sideways over the underside of the rocks; a welcome sight.

But no snails. No adult crabs. No live barnacles. No gulls dropping clams onto the stones. No flocks of birds feeding just off-shore.

This week, things are looking up. We caught the tide going out, and walked west from the park.

Looking west, towards Kwomais Point

I turned stones half-heartedly at first, finding the expected bare sand underneath. Sad. In the areas where we crunched over large dead barnacles, an odor of old cannery - stale, dead fish - overpowered the sharp aroma of saltwater. But as we went along,  we started to find hints of recovery.

A gull has found a juicy crab.

Burrowing anemone. Small, and just the one, but it's a start.

Purple starfish. We found four, looking healthy.

On the larger rocks, well to the west and in the mid-intertidal zone, the barnacles and mussels are doing fine. And we even found a few whelks; these and two others. 

And among the barnacles on some of the larger rocks, the bright green sea lettuce is starting to grow again.

I didn't see any shore crabs under stones this time, but a few of the tiny black snails that usually pepper all the stony areas showed up. One live clam lay on the sand, with his foot out, getting ready to bury himself. I helped him along, before a gull found him. And every stone sheltered amphipods.

From the center of the dead zone, I brought back a few pill bottles of sand and water. Last night, I examined two under the microscope. I found two copepods, an amphipod-like critter, something that looked like a busy hairy bacterium, a medusa, a long (at least under the 'scope) worm, and dozens of tiny swimming boxes and ovals and wormy things. It's not what it used to be, but it's young life.

I think the beach is going to make it.

Empty beach

Yesterday morning dawned clear and cold; there was ice on the birdbath again, but by noon the sun had banished it and the breeze was warm. A perfect day to go to the beach.

We hadn't been to White Rock since the day after the storm, back in November, the day I had collected the water that I believed had poisoned my aquarium. It was time to put unhappy memories behind us. We went to our usual spot on the White Rock beach.

A calm, sunny day. Setting sun warms the brown goldenrod heads.

We watched the train go by, I fed another bag of dry bread to shrieking gulls, we watched a kayaker or two. Then I went to the spot where I'd collected the last bottle of water, and started flipping rocks just below the high tide line. I wanted to either discard or confirm my conclusion about the water. Had the animals here suffered the same fate as mine at home?

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.

I had covered about 150 metres when I found one tiny limpet and an anemone. A bit farther on, there were two limpets, one mussel, and a very small snail, small enough to have washed in after the tides had cleaned the area.

After this, the population of amphipods was denser. Then I found three more limpets, and one miniature hermit. No crabs, though.

Just before the 300 metre mark (measured on Google, at home), one of the stones sheltered a handful of baby crabs, about 1/4 inch across the back. That was reassuring. And a couple of dozen steps further on, I up-ended a large rock, and startled a crowd; too many crabs to count before they scuttled off, a half-dozen small hermits, a mediium periwinkle snail, and a number of black "pinhead" snails, like crawling grains of coarse sand, and under, over and around them all, a mass of slithering amphipods. Yay!

From here on west, just off-shore, a flock of goldeneyes were diving for supper. There had been no birds near the dead zone, except the gulls that mobbed me for my bread, and left as soon as the bag was empty.

So it seems that I was correct: something in the water was probably the culprit. Next time, I'll search in the opposite direction, to see if I can estimate the size of the affected area.

Rocks at the shore, and Common goldeneye.