Monday, July 28, 2014

Sufficient unto the day ...

... is the weevil thereof.*

Wally Weevil

The weevil philosophy of life includes the maxim, "If you don't move a hair, they'll think you're not there." I had to drape myself over the compost bin, leaning at a precarious angle against the wall, making all kinds of sudden moves as the rotating compost bin cranked around, to get this photo. Wally Weevil, true to his principles, never even twitched an antenna.

As far as I know, he's there still.

*Yes, I know; that's not how it goes.

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Sunday, July 27, 2014

Looks like grungy tapioca pudding

The web is well named; Google is a net designed to trap you, a net full of bait and with unexpected hooks, until you're flopping like a salmon in the hold of a fishing boat, not knowing where you are, or how you got there. ... Where was I?

Oh, yes, double-checking info about the foam piled up along the beach in Boundary Bay. I promised to write about it yesterday, but then I dropped in on Google. Did you know it's illegal to catch octopuses in snares in BC coastal waters? Nor did I. Nor that fishing for ghost shrimp is a thing.

Along the way, I collected a bucket-load of acronyms from NOAA, itself more known by the acronym than by its unwieldy name, National Oceanic and Atmospheric Administration. And goggled at photos of whole towns engulfed by wind-blown foam.

Anyhow. This was about the foam. On our beach.

It looks like tapioca pudding with too much vanilla and green string. YMMV

This stuff piles up in a border about one or two feet wide all along the high tide line, from as far as I can see to the north and to the south. When the water recedes, it dries and disappears, leaving only the tangle of eelgrass and a coating of scum.

I find it rather off-putting; icky is probably a better word for it. When the wind blew my hat into the foam this week, I stuffed it in a plastic bag. At home, I soaped and scrubbed the hat so thoroughly that it lost its shape. I ended up tossing it in the trash.

And yet, I know that this scum is no dirtier than the sea water I wade in on the incoming tide. The brown tinge is probably from fine particles of the black, rotting eelgrass that lies in mounds above the tide line. As the foam comes in, it's white; only as it hits the shore does it turn brown.

Clean foam meets the shore.

The foam is caused by dissolved proteins and fats, the remains of dying seaweeds and dead critters, plankton and algae. They act like detergents, and have the same foaming action when the water is stirred by wind and waves.

Waves rolling in from a choppy sea in Boundary Bay last week. As they broke near the shore, they created suds.

Most sea foam is not harmful to humans and is often an indication of a productive ocean ecosystem. (From NOAA)

Here in the southwest corner of BC, we see foam most often in the summer months, when the water is teeming with the planktonic young of hundreds of species of ocean dwellers, when the sand is dotted with egg cases of lugworms and the eelgrass lined with assorted egg masses and ribbons, when the kelp forests are growing to their summer height; and when most of the frantic production of the next generation is bound to fail and to add to the dissolved protein in the water.

Lugworm egg case, about 4 inches long. Many of these dry out and die at low tide; this one is still in an inch of water.

Even when the water is calm, we get summer foam. These next two photos are from last July, on a rising tide.

Boundary Bay, from the eelgrass beds, facing Point Roberts.

Gobbets of foam floating inland with the tide.

But what about my worries about the ickiness of the foam? Don't we hear about shellfish poisoning and noxious fumes associated with the foam? Well, yes. But this is rare, or has been up till now. As the oceans warm up, and we pour more contaminants into the ocean, the hazards may multiply. But as it is now, the foam is mostly a sign of a productive ecosystem.

When there is a large die-off of an algae bloom, some of these algae release toxins into the water. These are taken up and concentrated by shellfish, especially mussels, super-efficient filter feeders. And when humans harvest and eat these contaminated shellfish, we get sick, sometimes fatally.

BC is home to the algae ultimately responsible for Paralytic Shellfish Poisoning (PSP). I have seen signs beside the access points to our beaches warning of this; all harvesting of bivalve molluscs (clams, mussels, oysters, etc.) is prohibited in the Lower Mainland. People still go clamming, and I haven't heard of any poisonings, but it's always a risk.

Clam diggers on Boundary Bay, getting the last of the catch in before the tide wipes out their sand bar.

Sign by Fisheries and Oceans Canada

I'm sure PSP was known to BC's First Nations from generations back, but the first documented cases (at least by Europeans) were in 1793:

British Columbia (B.C.), the Pacific province of Canada, has one of the longest documented histories of the severest form of harmful algal blooms, paralytic shellfish poisoning (PSP), along its entire 27,000 km coastline. The first documented case was in 1793 when four of Capt. George Vancouver’s survey crew became ill after a meal of mussels while charting the central coast (Mussel Inlet, originally named Mussel Canal, a side-arm of Mathieson Channel; see Fig. 23*). The location where they had the toxic breakfast of
mussels was named Poison Cove by Vancouver. One of them died five and a half hours later and the location of his burial was named Carter’s Bay.

(Taken from Harmful algal blooms in western Canadian coastal waters, by F.J.R. “Max” Taylor and Paul J. Harrison, UBC.)

* Near Bella Coola, Central Coast.

Today, various government agencies, such as NOAA in the US, Fisheries and Oceans Canada, and the Canadian Food Inspection Agency (CFIA), monitor our waters and shellfish for possible contamination, and issue warnings. As long as we pay attention, and eat only shellfish from safe sources, we can slosh about in the water to our heart's content, foam or no foam.

Most sea foam is not harmful to humans and is often an indication of a productive ocean ecosystem. (From NOAA)






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Friday, July 25, 2014

Tidewrack

With the tide at its maximum on Boundary Bay, I poked around in rolls of tangled eelgrass and under stones, and found nothing alive but a pair of barnacles broken off their rock. But the eelgrass had brought in many recently molted crab remains, their legs tied up in dripping green ribbons.

The waves and tide rip up tall eelgrass and create astonishingly complex knots with it.

"... the longer a string got, the greater the odds of knot formation became." From a study of the physics of knotted string, reported on Wired.

This little molt had been tossed up above the waves and was still intact.

Young molted crab, with sea lettuce. You can see, at the base of his carapace, where it separated to allow him to back out of his hard "skin".

I liked the rock he was on, too.

What makes that yucky-looking yellow foam? I'll explain tomorrow.




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Thursday, July 24, 2014

Eggs in barrels

This pretty stink bug was busy laying her eggs on a wall by the beach.

She's probably a Banasa dimidiata, also called the Banasa stink bug.

The name, "dimidiata" means "divided in half", referring, so some say, to the pattern on the pronotum (the front part of the thorax). And they're called stink bugs because of the offensive odour they emit when they're disturbed. A repugnatorial odour, it's called, produced by the repugnatorial glands.

They are found across Canada and the US, and are common in the Pacific Northwest. They feed on a variety of plants, including small fruits and berries.

Another photo, with the barrels of eggs in sort-of focus.

Zooming in on those barrels. Aren't they cute?





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Wednesday, July 23, 2014

Marina-less marina

Parked boats on Boundary Bay, at high tide.

And at low tide, they're lying on the sand.

10 photos merged to make a panorama. There was not much else to see, on a windy day with the water almost up to the walls.

I count about two dozen small boats there, between Point Roberts and Centennial Park. Click on the photo for a larger version.

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Tuesday, July 22, 2014

Another flower beetle

... with bright orange flower colours.

This one is a flower longhorn beetle, Xestoleptura crassicornis.

The glossy elytra (wing covers) and the orange antennae are diagnostic features.

BugGuide has about 3,600 photos of beetles in the flower longhorn family, about half of them decked out in vivid colours, reds and orange and yellow. I wonder if these are a sign to birds that the beetles taste bad, as is said about some other insects.

But then again, we're just guessing at that, aren't we? Maybe there is no reason at all; it's just the way things happened.

Any volunteers to taste a pretty beetle? I've lost my appetite. Or I'm allergic. Or my taste buds are old. (Any excuse will do.)

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Monday, July 21, 2014

In a playful mood

Clouds over Boundary Bay, last week:

Sometimes we forget how tiny we are, how puny!

But we huddle together for protection, and smile when the clouds are playing.

A Skywatch post.

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Sunday, July 20, 2014

No second chance

A spider can hang, perfectly still, in her web for hours. Days, even. Weeks, if she's guarding an egg sac. But if she decides that the clicky, flashy thing pointing at her is not to her liking, she's gone in an instant. Often one shot at a photo is all you get.


I aimed the camera at a web conveniently hung just where I was likely to run into it, as is the habit of the cross spiders around here. Before I had focused, the spider was at the far end of one of her tethers. I turned and shot, and then she was out of sight.

I'm surprised that the photo turned out ok.

Araneus diadematus, about 1/4 inch long. On sausage vine.


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Saturday, July 19, 2014

Tentacles!

Still testing shutter priority mode.

The anemones in my aquarium cause me no end of trouble, with their semi-transparent tentacles always in motion, and their habit of picking the most awkward spots to settle in.  I've taken hundreds of photos and deleted almost all of them. A fast shutter definitely helps.

Double lines in Val's tentacles. She often twists them in spirals like this.


A quick shot, with minimal processing; cropping, resizing, white balance is all.

The largest of the Orange Striped Green Anemones, Haliplanella lineata, (What a big name for such small critters!) has a good appetite, and a full crown of tentacles to keep it in groceries. It seems to have eaten something dark, which has left a black mark in the base, invisible in normal circumstances, but not when it's parked on glass.

These anemones have from 60 to 100 tentacles, up to about 2 inches long. This one is getting close to that maximum.

Feeding, this anemone has a pale greenish cream column. The upper half is the same translucent off-white as the tentacles. I was starting to doubt my identification, when in protest against the hot weather and my slowness in providing more ice, it shut down, condensing itself to a half-inch round dark green mass, with the orange stripes it's named for. Chilled and happy once more, the stripes disappeared.

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Friday, July 18, 2014

Testing Shutter priority mode

I usually keep my camera set to Auto, and toggle quickly from manual focus to autofocus. Both settings have their advantages; manual focus for face shots on critters that happen to be sitting still, autofocus for their more rambunctious moods. I've tried the aperture priority setting; it works out fine for larger objects, where I want the background to lose detail, but for the unpredictable smaller things, spiders and hermits and the like, it leaves me too often with the whole critter just out of range.

I hadn't tried Shutter priority before; "they" say it's for long exposures with a tripod, or on the other end of the scale, for sports and other fast action photos. And I rarely have opportunity for either.

But how about in macro photography, where the tiny subjects are almost too fast for my shutter finger? For the last few days, I've been experimenting with the fastest shutter speed setting my camera can handle. And I'm happy! I managed to "freeze" some amphipods!

Amphipod hiding in the sea lettuce, tests the current with one antenna, one leg. More legs are visible through the sea lettuce.

Tail end of an amphipod. Their legs stick out in all directions, which makes sense, seeing how they move about; they swim or scramble forward, backward, or sideways, "upside-down" in our terms, or right-side up; it makes no difference to them.

Courting pair, waiting for her (the small one) to be ready to mate. The male appears to be staring down a worm inching its way along the eelgrass. "Scram, or I'll stab you!" he says.

These photos are almost as they came from the camera, except for resizing and adjusting the white balance. I took out a few scratches on the glass, as well.

I had to jack up the ISO to 800, so there's a bit of noise in the darker areas, what with shooting through old glass and moving water. But the colours are truer than at my usual settings, and the flash doesn't produce the awkward highlights that show up at slower speeds. And even a running hermit crab gets his photo taken!

Very small hermit (less than 1/2 inch long) on a barnacled clamshell.

Another tiny one, at a crossroads high in the eelgrass.

Tentacles, tomorrow.


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Wednesday, July 16, 2014

Repeat customer

I've been working this week on learning how to use the Shutter Priority mode on the camera*. It has already been helpful: I managed to get decent shots of a large rove beetle with a mania for speed.

As usual, much of my practicing has been through the glass of the aquarium. Hermits, mainly, also as usual. But this guy is also learning something:

"Cheese!"

He came to the glass to look at me, so I took his photo. He stayed put, and I took another, and another, before I went off to chase an amphipod. When I came by again, Speckles, here, dropped his play and came to pose in front of the glass again. I obliged, taking another couple of photos, then moved on to look at a limpet.

The next time the camera flashed, he ran over to where it was, and struck another pose. Next time, the same. In all, I have photos from 7 short sessions, all at his insistence, all with him as close to the glass as he can get, staring straight into the lens.

Is it the flash that he likes? Or is he seeing himself mirrored in the lens? Does he understand that it's him, out there? Or just a friendly face?

Questions, questions.

* Sample shots, tomorrow. For now, I notice that colours seem more intense with the current camera settings, and the photos are sharper.


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Tuesday, July 15, 2014

Crowds and crowds

I've been playing instead of working, trying out random effects in my photo editing program. I liked this one:

People and boats in the distance, on Centennial Beach. Looking north towards downtown Burnaby.

Everywhere we looked, last Saturday, the beach was crowded with people, far in the distance to the north, south and east, some in the water, but most on the sand.

Humans weren't the only ones congregating in crowds. Here's another of those anchor buckets:

Hermits and snails, mostly. There's a fish hiding under the rope.

On the upper levels of the beach, most of these mud snail shells contain mud snails. Here, at mid-tide level, where rocks are few and the sand is clean, almost any snail I pick up turns out to be a hermit. They didn't find their shells here; the hermit shopping mall is quite a hike for a little critter. But they're fast, and determined.

If you look closely at these shells, you can distinguish several hermits by their visible big pincer and the "V" of eyestalks. Others only show up as a pair of hair-thin dotted lines; the antennae of Hairy hermits, Pagurus hirsutiusculus. (You might want to click on this to see it full size to find these, or go to Flickr and click on Full screen.) And see if you can find the little green hermit out of his shell, probably recently molted. His abdomen, usually hidden, is reddish purple, and curls in a tight spiral.

On the far right, there's a slipper snail on a slipper snail, on a hermit.

And over to the left, on the rusty upper lip of the bucket, a couple of hermits are wearing periwinkle shells. These are fairly rare on this beach, and only to be found in the upper intertidal zone. These hermits will walk a long way for a stylish outfit!

When the tide comes in, the hermits will leave their cozy bucket and scatter over the sand, looking for supper. And maybe the naked one will start the long hike back to shore for a new shell.

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Monday, July 14, 2014

Seen too late

On the wide, flat sands of Boundary Bay, residents park their boats helter-skelter, tying them to a variety of home-made anchor points. There is no need for a wharf; some people just wade ashore from a close tie-up, others, anchored farther out, use paddle-boards or small skiffs to reach their boat when the tide is in. The sand is dotted with these contraptions, sometimes a chain attached to something deep in the sand, or an old rope tied to a bucket of cement.

Each of these creates its own mini-environment, catching floating seaweeds or logs, providing holes and crevices for a variety of intertidal critters, and a solid substrate for barnacles and mussels. Sand flows around them as the tide comes and goes, making hills and valleys, semi-permanent tide-pools where a small fish can wait safely through the dry hours.

Walking on the sand at low tide, I veer from one anchor point to the next; no two alike, none uninhabited.

We stopped at this one yesterday:


A half-buried bucketload of cement, with rusted metal fittings, long turned into red stone, encrusted with barnacles and seaweeds.

The "face" of the bucket, with a small log and a deepish pool.

Both Laurie and I poked our cameras into those two holes; none of the photos were any good, but we did see what was inside. They are rusty metal tubes, probably where some sort of fixture to hold a boat was attached. The top one shelters several hermit crabs and snails; a small, green crab guards the door of the lower tube.

"You can't see me; I'm green, and I'm hiding under green seaweed!"*

*(That's assuming that a crab sees colours the same as we do, which is entirely unevidenced.)

On the downstream side of the bucket, the current has hollowed out a pool and a long, shallow valley, paving the valley with broken clamshells.

Refraction through a couple of inches of water.

And where the shells peter out, in a calm backwater, worms keep on feeding while the rest of the beach lies dormant.

These are the largest worm tubes I have seen on the beach, up to 3 inches tall, standing firm.

They remind me of tipsy pilings left behind when an old wharf is demolished. But these have neat holes in the top, and if you look closely at the right moment, transparent tentacles reaching out.

And look again! See that whitish thing near the centre, that square with a tail? I didn't, when I was taking the photos, and it turned up on a half dozen. So I missed out; must be more observant.

The Mud-flat Hooded Shrimp, Nebalia pugettensis!

I last saw one of these 4 years ago. And the one before that was another 4 years earlier (Two posts). They're probably plentiful on the beach, but they're usually burrowing in the muck. This may be a dead one, or a molt. The live one I found had blue eyes; the dead ones I'd seen earlier had red eyes.

If you look back at the first photo of the Nebalia, you might see the second one, down by the lower right hand corner, half-hidden behind a blade of eelgrass.

And here's another one:

Very hairy green crab, not bothering to hide. And just below the broken shell at upper left, another Nebalia.

This one has no colour left. It must be a molted carapace and legs.

I hope I don't have to wait another 4 years before I see my next mud shrimp.

Next: another bucket.


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Sunday, July 13, 2014

Honeysuckle

Hanging over a fence at Boundary Bay beach:

Pinks, peach, and purples, all in one flower.

Coming up: tide pool critters, and worm collectors.

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Saturday, July 12, 2014

And another ...

It's moth season. Every time I water the garden, or pull a weed, or check a hosta for slugs, I wake up a big yellow underwing, or a little whitish, fluttery moth, or something dark that flies straight at my face and disappears before I finish ducking.

This afternoon, I discovered this one, sleeping on my bathroom wall. I didn't wake it up.

I love the pattern on these wings. They measure 2 inches, wingtip to wingtip.

Another one to attempt to identify before I bother the good people at BugGuide.

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Friday, July 11, 2014

Why my desk always faces the window

I look up from the screen, and see this, almost at arm's length:

Small moth, facing me through two layers of glass. Splotchy green garden background equalized digitally.

I went outside and managed to measure the moth (2 cm. wingspan) and take a few photos before he flew away. Because of the confusing background inside, I taped a couple of pieces of felt, the handiest thing available at the moment, to the inside of the window.

Moth on pink felt.

Moth on green felt, with shadow.

This last photo is not very good, but comparing it to the one on pink shows how transparent those wings are; you can see the pink or green background colour through them.

The moth is still unidentified. I'll head over to BugGuide as soon as possible.

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Wednesday, July 09, 2014

Gift wrapped

I found this on my doorstep a few mornings ago*:

Hairy cocoon.

I don't know what made this. It's 2 cm. long, sort of egg-shaped, and soft to the touch. The spiky hairs sticking straight through the covering look as if they belong to a woolly bear caterpillar. The whole thing was fastened to the rag rug underneath, glued or interwoven.

I have it in a container with a perforated lid, and I'm keeping a watch on it to see what emerges.

*A favourite cat used to leave me a line-up of mouse tails. I prefer this sort of "gift".

(Note: I'm still here, just extremely busy. And tired. Blogging will be catch-as-catch-can for the rest of this week.)


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Monday, July 07, 2014

Hermit complaint

And revenge.

"It's no fun being small, ...

when the big guys walk all over you, ...

And knock you all topsy-turvy.

But two can play at that game.

There! How do you like them apples?"

... says Junior, going off to tell his buddies up on the eelgrass all about it.

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Saturday, July 05, 2014

Subbing spider.

It's late. I've been playing with the camera and watching snails lay eggs, and now it's too late to process the photos tonight.

Have a fat spider, instead.

He's been sitting under the same sausage vine leaf for days, hardly moving, even when I turn his leaf over. Waiting for a mate to move into the vicinity?

Very obviously a male. Look at the size of those boxing glove pedipalps!

Detail of one of the pedipalps. He uses these to transfer sperm to the female. When he finds one. If he ever overcomes his shyness.

Coming up: those snails and eggs, a couple of tubeworms, and hermit silliness.


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