Showing posts with label eggs. Show all posts
Showing posts with label eggs. Show all posts

Wednesday, May 10, 2017

Also present ...

And ... the rest of the animals I found on that one trip to Stories Beach, in no particular order:

A Black prickleback, Xiphister artopurpureus. Look for the thin white lines radiating back from the eye; his pal, the rock prickleback has wide pale lines in a black field instead.

Red rock crab, running for cover.

Bright yellow or greenish yellow eggs, possibly belonging to a clingfish.

A couple of tiny hermits, dwarfed by the dogwinkles and isopods around them.

Rockweed isopods come in a variety of colours, from green to warm browns, to purplish blacks. I hadn't seen one before with that distinctive dark and light green pattern. Could it be a different species? 

Unidentified sculpin.

"Coloration is often virtually useless as a tool for identification. Extreme variation is the norm." (Marine Life of the Pacific Northwest, VB62)

Purple sea star. I saw several dozen, all healthy. Good to see, after the onslaught of Sea Star Wasting Disease that wiped out so many.

Where the worms are.

According to Kozloff, these are probably the tubes of bamboo worms, hiding 6 inches or more below the surface of the sand. Some day I'll manage to dig one out, to be sure.


Sunday, May 01, 2016

Fishing boat dock, revisited.

Last November, I explored the docks where the fishing boats tie up, peering down into the water between the dock and boat sides, and between the old creosoted pilings. The winter has come and gone; the sun shines down the cracks and into the dark crevices again. I retraced my steps yesterday.

There was a stiff breeze, strong enough to blow my jacket over my head when I bent over; the open water was white-capped. The docks danced on the waves, bouncing against the pilings, making squeaking, creaking noises; cables under stress whined, old wood groaned. I had to be cautious, poking my head down gaps over dark water, careful not to let a swaying dock pin my hand against a piling.

Last winter, I found shrimp, kelp, red rock, and black-clawed crabs, purple starfish, yellow sponges, anemones, and a nudibranch. And styrofoam. Too much styrofoam.

This spring, the population mix has changed.

There were still kelp crabs, most quite large.

A large kelp crab on a piling, half underwater. From the way she holds her abdominal plate, half open, I think she's in berry, carrying a mass of eggs. What looks like a lump on her right shoulder (our right) is probably an effect of the water; when she moved about, it disappeared. The blobs on the lower left are styrofoam-coated gunk.

Mussels, along the bottom of a boat. With pieces and dust of stryrofoam.

Around almost every piling, the edges of the dock were covered with brownish, matted weed and these pink and yelllow lumps. I think they may be peach ball sponge, or something similar.

Some of the sponges were a vivid orange. I don't know if these are colour morphs of one species, or three different sponge species.

A circle of twisty, lumpy chains. I saw only one, and couldn't get closer. The circle is about 2 inches across. Eggs, but of what species?

On one of those rubbery boat fender balls, large barnacles have lived and died, leaving empty shells.

These, rescued from an old rope, are pinkish.

I saw no shrimp, though I looked carefully. There were many tiny, darting fish, several orange starfish, down deep; one looked like a leather star or cookie star, with short, wide arms. I couldn't find any purple stars.

Above the water line, there's this:

Old wood, rust, cracked paint, and an opportunistic weed, going to seed.

And there's still too much styrofoam.

Tuesday, July 10, 2012

Singing toadfish

... or, under every rock, a new marvel.

I flipped a broken paving stone at the top of the intertidal zone, just off the end of the boat ramp. Here, the shore is rocky and difficult underfoot; long ago, someone laid out a few square pavers, but with time and heavy traffic, they have all broken, and lie helter-skelter among the more "natural" rocks. At high tide, the water covers the end of the ramp, and is about a foot deep over this rocky stretch.

But the tide was going down; the stones were exposed but still wet. Flipping a few disturbed hermit crabs and a handful of green and purple shore crabs. A larger stone, lying not quite flat on the rocks, had a pool of water underneath, and in this pool was a fish.

Plainfin midshipman, Porichthys notatus, aka the singing toadfish.

Detail of the round fins and strong spines on the back.

This was the same species as the one we found out of the water last week at White Rock, and about the same size; approximately 10 inches long.

He  -- it's a male -- wasn't alone. The underside of the rock was covered with a layer of eggs.

A brilliant orange, shining in the sunlight.

Part of the mass of eggs was shimmering and vibrating constantly. I couldn't see what was happening, ...

but the camera could. Look closely. See the eyes? And the translucent , pink, comma-shaped bodies? The're fry; baby fish. Cute!

Singing toadfish come in three types; females, and two different males; they call them Type I males and Type II males.
Type I males are eight times larger in body mass, and have much larger vocal organs. Type II males’ reproductive organs are seven times the size of type I males. Female and type II male midshipman fish can be distinguished from each other by the female’s slightly larger size, and the type II male midshipman’s large reproductive organs. (Wikipedia)
The way it works is this; a large Type I finds himself a nice rock to hide under near the top of the intertidal zone, and digs a nest. When night comes, he starts to sing. (Well, sort of; it's a hum or a buzz. Listen. Whatever you call it, the female likes it.) When a female joins him, she lays her eggs on the underside of the sheltering rock and he fertilizes them. Then she leaves, and he babysits until the eggs hatch and the young fry leave the nest.

And where do Type II males come into it? They are about the size of a female, and their voice is similar to hers. Their mating strategy is to deceive a Type I into mistaking them for females and allowing them to enter his nest. Then the two wait together for a mate; when she arrives, sneaky Type II fertilizes the eggs, and swims away, leaving the cuckolded Type I to do the job of parenting.

These fish are nocturnal; even when they're not brooding, they hide under rocks during the day. At night, they hover over the bottom, laying in wait for prey. On their sides and belly, they have rows of cells which, if their diet includes the right species of copepods, emit light. This may serve as camouflage against the lighter sky, or possibly may attract prey.

The fish at White Rock, showing the lines of photopores.

There's a great photo of eggs and fry on Flickr.
Buzz has photos of a raccoon catching and eating these fish.
A good photo of the photopores and a note about poisonous spines. Warning: hands off!


Friday, June 29, 2012

I promised you snail orgies.

We found the tide almost at its minimum at Crescent Beach, and I waded out through inch-deep tidepools, trying to get to the drop-off before the water rose again.
Looking back at the shore from half-way out.

The eelgrass comes in patches in this section of the beach. The sand was mostly bare, but where there was eelgrass, there were snails.

The invasive Eastern mud snails, Ilyanassa obsoleta, in eelgrass.

This snail has just about driven out our other invasive, the mudflat snail, Batillaria attramentaria, that we see in the millions on the opposite side of the bay, at Centennial Beach. I saw a couple or three only among these herds of mud snails.

"Hurry, hurry! You're late to the party!"


The snails were in full mating frenzy, piled several deep, hundreds of them to a pile, writhing and rolling, a mass of squirming black bodies and grungy shells. Every so often one flipped completely upside down, stretching out to show her white underside, waving her siphon excitedly. What with all the gunk on their shells, the stirred-up sand, and the curtain of eelgrass, it becomes difficult to distinguish individual snails.

And along with the fun, comes the work. Once they have mated, the females find a hard surface and start to lay eggs. Here, the surface is usually an eelgrass blade, where they line up the eggs in rows.

Eelgrass with snail egg "beads". And snails three-deep beneath them.

Each transparent egg capsule contains from 30 to 300 yellowish eggs. They are firmly glued to the eelgrass, and feel like a cold, hard lump of jelly.

A closer view of some eggs. The furry stuff is probably a colony of hydroids.

Close-up of some capsules I brought home in 2008, showing the individual eggs.

A couple of snail heaps were not interested in sex. No writhing, no sand-stirring, no coupling, no egg-laying; they had something else on their minds. In both cases, the molted remains of a crab lay on the sand, with a tidy mass of snails around and under it. They're algae eaters, but they also love a scavenged meal of animal flesh.

A little after-orgy snack?

Thursday, October 13, 2011

In a handful of moss

We've not been able to get out of urban environments for a while; all our outings have been to family gatherings or running errands. And since the weather changed, most of our bugs and other critters have disappeared, except for the one carpet beetle larva and a crop of fruit flies.

I was hungering for something green, something wet, something alive and slithery. So, at the end of another day hopping from store to store, I went out in the rain and gathered a few tufts of moss; tiny will do; let my camera do the walking.

Green and wet.

The moss was beautiful, glowing translucently under my light, the spiky leaves green at the top, a rich brown beneath. Underneath, where the moss still held remnants of soil, a couple of miniature slugs were sleeping. Disturbed, they woke and stretched, heading for new cover. At their full length, neither was more than a half inch long.

When I pulled the largest clump of moss apart, I exposed a cozy nest.

Slug eggs, almost as big as the slug diameters.

A closer view, trying to distinguish features of the developing slugs inside. No luck.

Closer view.

Apart from the slugs, their eggs, and one tiny earthworm (so tiny he crawled into my eyedropper), the only other visible animals were black springtails, from pinhead size on down to mere visibility, racing and hopping around. I found one stopped for a breather.

Springtail, Collembola.

Under a good lens, I found more animals: a little black snail, barely a pinprick to the naked eye once I knew where to look for it; another earthworm, identifiable as such only under the microscope, and a few slow-moving, beautiful, shiny, deep red mites. I took photos, but they show only red-black spots with a hint of legs along the edge.

This different mite was about twice their size:

Unidentified mite. 

It has eight legs, but holds the first two high in front, like antennae. And it looks like it's carrying at least one, maybe two smaller mites on its back. Babies? Or parasites? Maybe they'll know at BugGuide. I'll ask.


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