Low tide at Brown's Bay

The tide, when I arrived in Brown's Bay last Thursday, was the lowest I've ever seen it. At one point, I could almost have jumped from one of the docks at the marina to the shore without getting my feet wet.

The hill beside the marina. The bare rock is underwater at high tide. The difference between low and high tides that afternoon was just over 4 metres.

The sea creatures that live on the floats beneath the docks never worry about tides; it's always high tide for them. But for the rest ... I checked out the beach; it's not heavily populated; too much pollution from the cannery next door and the marina and floating restaurant, I think. There were crabs and rusty rockweed, a few limpets. 

But behind the restaurant, down deep where light rarely reaches, I could see masses of tall white anemones, looking like underwater clouds. I still couldn't see the bottom; it drops away quickly here. There are no photos; all the camera saw down there was white blobs.

The other end of the bay, an hour later. The tide is coming in, but there's still a good bit of bare rock. All these rocks are usually underwater.

"They" have scraped off the floats again, but the critters always come back:

Anemones,  Metridium senile, and limpets on a blue plastic float.

Winged kelp, Alaria marginata.

A few white plumose anemones were hanging out beneath the restaurant. The current was running fast at this time; the water is full of specks and fragments of seaweed. And tiny jellies.

Jelly, probably Aequorea sp., aka water jelly, many-ribbed medusa ...

Another, being swept along with the current. Many were travelling too fast for me to aim the camera at them.

Almost invisible unless the light caught them just right; otherwise all I could see were the vanishing circles on the surface, where they touched and sunk again. There's one at the far right. I think these are herrings, a few centimetres long.

I always look for swallows in Brown's Bay. Next.

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La marea, cuando llegué a Brown's Bay el jueves pasado, estaba casi a su nivel mínimo; no la he visto antes tan baja. De uno de los muelles de la marina, casi podría haber con un salto (y eso que ya no soy tan joven) alcanzar la playa sin mojarme los pies.

    1. El cerro al lado de la marina. La roca desnuda está bajo agua con la marea alta. La diferencia entre marea alta y baja esa tarde era un poco más de 4 metros.

Las criaturas marítimas que viven en los flotadores debajo de los muelles no se preocupan por las mareas; para ellas, siempre estamos a marea alta.  Pero las demás ... Busqué en la playa; no hay mucha vida allí, creo que puede ser por la polución que produce la enlatadora, la marina, y el restaurante flotante. Había cangrejos pequeños y algas marinas, Fucus sp., manchadas. Y algunas lapas.

Pero atrás del restaurante, en las profundidades donde la luz pocas veces llega, vi muchas anémonas grandes y blancas; parecían nubes sumergidas. Pero todavía no veía el fondo; aquí baja rapidamente. No hay fotos. Lo único que veía la cámara eran masas blancas borrosas.

    2. El otro extremo de la bahía, una hora más tarde. La marea ya empieza a subir, pero todavía hay mucha roca desnuda. Todas estas rocas están bajo el agua casi siempre.

Los dueños de la marina han limpiado los flotadores de nuevo, pero las criaturas siempre vuelven a establecerse.

    3. Anémonas Metridium senile y lapas en un flotador de plástico azul.

    4. Quelpo alado, Alaria marginata.

    5. Bajo el restaurante, algunas anémonas blancas están cerca de la superficie. La corriente andaba muy rápido en este momento, y el agua estaba llena de cosas flotantes, pedazos de algas marinas, y muchas medusas miniaturas.

    6. Una medusa, probablemente Aequorea sp.; aquí las llamamos medusas de agua, o medusas de muchas costillas.

    7. Otra medusa arrastada por la corriente. Muchas se llevaban tan aprisa que no alcanzaba a enfocar la cámara.

    8. Peces juveniles, arenques, creo. Desde el muelle solamente eran visibles desde ciertos ángulos. Desde otros puntos, nada más se distinguían los circulitos que hacen al tocar la superficie; se ve uno de estos a la derecha.

Siempre busco las golondrinas en este lugar. Mañana cuento lo que vi esta vez.

Anemone doings

Intertidal plumose anemones stand tall underwater, waving their tentacles (up to 100) about, catching small prey. When the tide goes out, they droop, hang straight down, following the water as it recedes. As long as the water reaches the mouth, the tentacles stay extended; there's good food to be caught in the ebb and flow.

When the water is gone, the anemones retract their tentacles and contract their bodies, squeezing out the water that bulks them up. Eventually, they end up hanging limply, looking like slimy old rags. They're fine; when the tide comes up again, they'll inflate, spread out the tentacles and get down to the business of fishing.

I caught this group in that half-way stage, some still with their mouths in the water, some closing up shop.

Plumose anemones, Metridium senile.

Four anemones. Two have their tentacles still in the water. The one on the left is on the point of closing  down; the one on the right is still busy feeding. As it has turned downwards, now its tentacles brush the sand; see what effect that has, in the next photo. Note, also, the stretched stem; taking on its old rags look.

Angry anemone

A lot is happening in this photo. Three anemones still feeding. Two shrinking, with tentacles retracted. Look at the one on the right; it's dripping, and it has shed inedible grains of sand that stuck to it as it hung down, now resting on the tentacles of the one still open.

The one in the centre is unhappy. These anemones, when disturbed or threatened, shoot out fine white threads through the column wall. These threads, called acontia, contain stinging cells. They may be discharged as protection against predators, such as nudibranchs.

These thread-like extensions ... are filled with nematocyst-containing cnidocytes ... the dart-like tubules are propelled from the nematocysts with enough force to penetrate the exoskeleton of the predator to sting its target with ... toxins that cause paralysis. (PubMedCenter)

Or they can  be a territorial marker. These anemones are clonal; they live in groups of their own clones. When they find themselves too close to another of the same species, but of a different clone group, they expel the acontia. "Stay away!"

And they don't like the aggregating anemone, Anthopleura elegantissima. When they contact one, there go the acontia. It is possible that the one above has met one of these down there under the rock. Or could there be a nudibranch hiding in the dark?

Ten years ago, I had to move a plumose anemone in my tank, and she was extremely annoyed. Here she is, shooting acontia at me.

"Metty"

Story here.

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Las anémonas intermareales se mantienen erguidas en el agua, agitandos sus tentáculos (que pueden llegar a 100) capturando su presa. Cuando la marea baja, se  desinflan, se doblan, colgándose con lost tentáculos vueltos hacia abajo, manteniendo la boca en el agua. Siguen pescando; en el agua en movimiento siempre hay comida buena.

Cuando por fin no encuentran agua, retraen los tentáculos y se contraen, expulsando el agua que les da forma. Terminan colgándose flácidamente; parecen trapos viejos. Pero están bien. Cuando sube la marea, se volverán a inflar, volverán a extender los tentáculos y dedicarse de nuevo a la pesca.

Encontré este grupo de anémonas en medias res.

    1. Anémonas plumosas, Metridium senile.

Aquí hay cuatro anémonas. Dos todavía tienen agua para sus tentáculos. La de la izquierda está a punto de retraerlos; la de la derecha sigue alimentándose. Por estar ahora boca abajo, sus tentáculos están en contacto con la arena; en la próxima foto se ve lo que esto ocasiona. La columna ya se está extendiendo, ya empieza a tomar la forma de trapo viejo.

    2. Una anémona enojada.

Mucha actividad se ve aquí. Tres anémonas están pescando. Dos se están encogiendo, con los tentáculos retraídos. La de la derecha gotea, y  ha dejado caer granitos de arena que se le pegaron al extenderse hacia el fondo.

La anémona del centro está de malas. Estas anémonas, al estar amenazadas o simplemente irritadas, expulsan hilos blancos por la pared de la columna. Estos hilos, llamados acontia, están armados con células urticantes. Pueden servir como protección contra los predadores, tales como los nudibranquios.

Estos tejidos filiformes ... están llenos de cnidocitos que contienen nematocistos ... los túbulos en forma de flechas se disparan desde los nematocistos con sufficiente fuerza para penetrar el exoesqueleto del predador e inyectarlo con ... toxinas que causan una parálisis. (PubMedCenter)

O pueden servir como marcador de territorio. Estas anémonas son clónicas; viven en grupos de sus propios clones. Cuando se encuentran cerca de otra, de la misma especie, pero de un clon distinto, producen las acontias. "¡Lárguense!"

Yno les gustan las anémonas agregadas, Anthopleura elegantissima. Cuando se ponen en contacto con una, orta vez expulsan las acontias. Es posible que la anémona de la foto haya encontrado una de estas otras anémonas debajo de la roca. O puede haber un nudibranquio escondido allí.

Hace diez años, tuve que cambiar de sitio una anémona plumosa en mi acuario, y ella se puso muy enojada. Aquí está amenazándome con muchas acontias.

    3. Se llama "Metty".

La historia está aquí.

Shapes in the murk

Cloud cover: 100%. So reads the weather report for most days recently. 98 to 100%. And we have barely 8 hours of daylight, but for the first and last of those hours it's too dark to read outside. Even when it isn't raining.

I'm not grumbling; that's our end of the year island weather; those misty days, the days of muted greys, of hillsides that blend into the sky, of tree silhouettes and the cries of gulls made musical in the damp air.

It wasn't raining, and there was no breeze to ruffle the water, so I went down to the docks to peer under the floats. Dock fouling, they call it; looking at the life that "fouls" the human structures. A one-sided way to look at it; don't our plastics and oils and trash contaminate the habitat of all that underwater life?

Anyhow. It was too dark, even at midday, to see much underwater. I saw orange starfish down on the rocks and many feather duster worms on the underside of the floats, all vague shapes in the murk. But there were bright white plumose anemones just under the surface.

Metridium senile, on an underwater hose. The seaweed is a blur in the dark water.

Many of the old pilings have been replaced by metal ones. I'm not sure why, but so far, even the algae have left them bare. But some of the wooden ones remain; here I found good-sized kelp crabs.

Creosoted piling, with barnacles and a leggy kelp crab, waving his chelipeds at me.

Armed and dangerous. Or so he wants me to believe. Lots of barnacles on this piling.

Another plumose anemone.

And another. The netting can be seen, faintly, through the flesh of the anemone.

This was very dark, and I had to jack up the lighting. The feather duster worm, to my eyes, looked dark purple. The sponge looked dull orange.

I kept that photo because of the leggy critters that crawl on the pipes. They look to me like skeleton shrimps; I haven't seen these under the docks before.

Skeleton shrimp, in my aquarium, 2015. Male (large) and pregnant female.

As I headed back to dry land, the sun was attempting to break through the clouds.

As bright as it got. This was at  3 PM.

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Nubosidad: 100%. Así dice el pronóstico meteorológico para casi todos los dias ahora. De 98 a 100%. Y nos quedan ahora apenas 8 horas de luz a diario, pero en la primera y última de esas horas, sigue tan oscuro que no se puede leer afuera. Y eso, cuando no llueve.

No es una queja; así es nuestro clima aquí en la isla hacia el final del año; esos dias de neblina, de los tonos grises apagados, de cerros que se desvanecen entre las nubes, de siluetas de los árboles y de los gritos de las gaviotas que se vuelven música por la humedad del aire.

No llovía, y no había brisa para levantar olas; fui al muelle para ver que se podía encontrar bajo los flotadores. Pero estaba bastante oscuro, aunque era todavía media tarde. Vi estrellas de mar en las rocas debajo del agua, y muchos gusanos plumero, pero todos como formas imprecisas entre las sombras. Pero sí había anémonas blancas justo debajo de la superficie.

    1. Metridium senile en un tubo. Las algas, sin luz, se borran y pierden sus colores.

Muchos de los pilotes viejos se han cambiado por pilotes de metal. No sé porque, pero hasta ahora  ni siquiera las algas se han establecido en ellos. Pero todavía hay algunos de los pilotes de madera; aquí encontré cangrejos kelp bastante grandecitos.

    2. Pilote pintado con creosota, con bálanos y un cangrejo kelp, amenazándome con sus quelípedos.

    3. Peligroso. Por lo menos, eso es lo que quiere hacerme creer.

    4. Otra anémona plumosa Metridium senile.

    5. Y otra. Se ve la red através de su carne translúcida.

    6. Este gusano plumero estaba en un sitio muy oscuro, y tuve que aumentar la luz de la foto. En el sitio, se veía de un color morado muy apagado, y la esponja, que aquí se ve amarillo estaba más bien un café algo anaranjado.

Subí la foto a causa de esos animalitos patilargos que se ven en la tubería. Parecen ser Caprellidae (que aquí llamamos camarones esqueleto, y no son ni camarones ni esqueletos).  No he visto estos antes en los flotadores, solamente en algas intermareales.

    7. Una pareja de caprellidae en mi acuario, 2015. El grande es el macho.

    8. Mientras regresaba a tierra firma, el sol trataba de penetrar las nubes, pero pronto volvió a esconderse. Esto fue a las 3 de la tarde.

Pointy

 Reaching out ...

Spiky. Baby sea urchin sheltering in empty mussel shell.

Tentacly. Plumose anemone, "Metty", feeling fine.

The sun came out this morning, and I went for a long, long walk. Tomorrow there'll be photos of beach findings.

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Estirándose ...

Mi erizito de mar, descansando en una concha vacía de un mejillón.

Y mi anémona plumosa, a la que he dado el nombre de "Metty", feliz, esperando su desayuno.

Hoy salió el sol en la mañana, y me fui a caminar por largo rato. Mañana, habrá fotos de lo que hallé en la playa.

Under the water line

 The wharf, on the sunny side, is a quiet place, a watery parking lot. There are a few people, gulls, a dog or two, maybe even a cat. Sometimes a heron.

But on the underside; that's another story. There's more busy and crowded biodiversity there than in the entire city of Ankh-Morpork*.

Plumose anemones, sponges and much more, on the side of a float.

At first glance, this is a mess. Too much going on; too crowded, too many shapes. So I've added labels to the photo. It might be a good idea to click on it to bring it up to full size.

There's even a nudibranch!

Another anemone, same species, with friends.

And here it is, with labels. Help me out here!

And another photo, from a wharf edge in full sun:

A few barnacles grow above the water line, in the splash zone.

And here it is, labelled:

The worms like the dark better.

Summing up: there are anemones, sponges, tunicates, barnacles and mussels and limpets, assorted feather duster worms, at least one nudibranch, a sea urchin, hydroids, assorted algae. Present, but not visible, are a full contingent of amphipods, copepods, assorted worms out of tubes, assorted worms in tubes, snails, bryozoans, probably some isopods, maybe a few shrimp. The usual crabs are not the one here, which I think, seeing only the underside, is probably a shore crab; the usual crabs are kelp crabs, longer-legged for crawling on floaters, and an olive-green colour which makes them hard to see. 

But there is still more! I'll upload a few more photos tomorrow.

*Which includes trolls, dwarfs, golems, werewolves, vampires, banshees, gnolls, gnomes, Wee Free Men, zombies, talking dogs, ditto ravens, gargoyles, elves, goblins, orcs, Death, incarnated auditors, the 5 horsemen, bogeymen, and humans, just taking into account the "intelligent" (although not necessarily wise) species. And not counting the yeti, who is wise enough to stay up in the snows.

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En el muelle, todo es tranquilo; al fin es un estacionamiento, aunque sea sobre agua. Hay algunas personas, gaviotas, uno que otro perro, tal vez hasta un gatito. Y a veces una garza.

Abajo del agua, ya es otra cosa. Hay un ecosistema tan diverso, tan lleno, que es difícil verlo o describirlo.

En estas fotos, tomadas al lado de dos flotadores, hay: anémonas, esponjas, un nudibranquio, cientos (aunque solo se ven algunos) de anélidos, uricordados (tunicados), lapas, mejillones, cirrípedos, hidroides, y un cangrejo. Y muchas algas, rojas y verdes, que se intermezclan con los anélidos que viven en tubos y, abiertos, se confunden con los hilitos de alga.

Hay mas animales aquí que no se pueden ver, pero por cierto están escondidos bajo el alga: anfipodos, copepodos, más anélidos, briozoos, caracoles, probablemente unos isopodos, y camarones. Los cangrejos que veo a seguido no son como el que aparece en la foto, un cangrejo que más bien se halla entre las piedras en la playa, pero un cangrejo "kelp" que tiene las patas larguísimas para mejor agarrarse a los flotadores, y de un color verde oliva, que lo hace muy difícil de ver entre el alga.

¡Hay más! Subo más fotos mañana.

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.