Mee-Kwa-Mooks Beach 4/7/12
Coordinates: Lat: 47.56465
Lon: -122.40846
Weather: Very sunny with a completely cloudless sky, but strong winds bring the temp. way down and ruffle the surface of the water.
11:30am -- The tide is very low, and for the first 1.5 hours it is on its way out (at 12:30pm it turns). The beach is perhaps 100m wide from the water to the barge/wall. The upper 20-30m is quite dry, but still decorated with barnacles and crispified seaweed, indications that the tide was at least once covering it entirely- perhaps up to 3m up the wall. The beach is rocky and very dark, the ground looks almost black from above. Perhaps this is a result of an active tide, i.e. lack of sunbleach? Rocks vary from tiny to 16x16cm or so, with one sandy patch of about 50 square meters and one patch with larger boulders. In the intertidal zone (the lowest 20m or so of the beach) there is 5-6cm of water, slightly undulating with the tide.
A large flock of Brant Geese (Branta bernicla) float right along the water line, not coming onto the beach nor floating far out. They feed on eel grass, keeping the close to the shallowest bit of the shoreline. What beautiful birds! And what a long journey they make along the coast of the entire Pacific, spending a great amount of their time in the arctic where they have very little contact with humans. Perhaps it is as a result of their lack of much human contact that they remain quite wild birds- easily disturbed by humans and dogs.
The inter-tidal zone is delicate! Each creature accustomed to life under water (where most inter-tidal creatures breathe and feed) is stressed when exposed to air, sun and a host of new predators. While the inter-tidal zone appears mooshy and bleak, a closer look reveals SO MUCH! Many many creatures call the dense eel grass home, so we try to step in it, but even the sandy spots between the grass are packed with anemone and clam siphons. Barnacles cover all- giving everything a spikey, crunchy exterior. A plethora of seaweed types cover the ground, and we see eggs everywhere, some just floating and some connected to rock or bits of seaweed. The tide seems rich and fertile, not unlike the forest in spring. All of these blind creatures are able to sense and react to each other. But how in the world?? I am told that when a Sunflower Sea-star (Pycnopodia helianthoides) enters a tide pool everything else "runs" away--how do they know that it is a predator without eyes or any other senses that we can comprehend?
Species List:
Birds--
Osprey (Pandion haliaetus)
Bald Eagle (Haliaeetus leucocephalus)
Brant Geese (Branta bernicla)
Molluscs--
Horse Gaper Clam (Tresus Capax)
Dog Whelk (Nucella lapillus)
Rough Keyhole Limpet (Diodora aspera)
Mussels (Genus: Bathymodiolus)
Cockells (??)
Merten's Chiton (Lepidozona mertensii)
Sand Dollars (Order: Clypeasteroida)
Dungeoness Crab (Metacarcinus magister)
Purple/Ochre Sea-star (Pisaster ochraceus)
Sunflower Sea-star (Pycnopodia helianthoides)
Christmas Anemone (Urticina crassicornis)
Sea Lemon Nudibranch (Anisdoris Nobilis )
Plants--
Eel Grass (Genus: Zostera)
Iridescent Seaweed (Mazzaella splendens)
Observaciones
Fotos / Sonidos
Qué
Galleta de Mar Excéntrica (Dendraster excentricus)Observ.
jesscubbDescripción
In a low, inner part of the beach small bumps in the smooth sand indicated the presence of these sand dollars just below the surface. Many, perhaps hundreds, were inter-laid in an area of about 20x10m. The purple fuzz covering both sides of this creature was moving as I looked closely. Certainly reacting to having been yanked from its sandy home and exposed to light. In the very center of this one is a hole that I presume is the mouth, this was face down in the sand, which means the sand dollars must eat something out of the sand, not from above it. I wonder if they emerge out from under during the high tide? Can they move? Thanks to Celso Reyes for snapping this photo and sharing it with me when my camera was out of batteries.
Fotos / Sonidos
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Cangrejo Dungeness (Metacarcinus magister)Observ.
jesscubbDescripción
This is a crab molt, i.e. the perfectly intact shell left over from a crab that outgrew it. But I am not sure of the type of crab. You can identify a crab molt if you find a shell that opens cleanly when you lightly lift up the back side, or "open the back door." A regular dead crab will still have the meat inside, and the shell will not open easily. When crabs outgrow their shells, they molt and then spend a few weeks growing a hard outer shell, how vulnerable they must be during the inter-rim, completely exposed and without claws at all. Thanks to Celso Reyes for taking this photo for me when my camera was dead.
Fotos / Sonidos
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Zirfaea pilsbryiObserv.
jesscubbDescripción
There were hundreds of these peeking out of the sand at low-tide on Saturday. They are very similar to geoducks, but with much smaller shells and far more common. They are unable to completely retract the siphon within the shell, but do sink completely below the sand when they detect vibrations above the sand, i.e. human footsteps. Both of the holes belong to the same clam, but one is for taking in water and the other expelling it in the characteristic clam squirt. Thanks to Celso Reyes for snapping photos when my camera was out.
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Estrella Girasol (Pycnopodia helianthoides)Observ.
jesscubbDescripción
The terror of the tide pools, sunflower stars eat anything and everything. This one was moving towards a live dungeness crab as we watched it, even though starfish do not feed out of water. Starfish feed by pushing out their stomachs and digesting their food without ever having to in-take it. Thanks to my friend Celso Reyes for taking photos when my camera was out.
Fotos / Sonidos
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Estrella Ocre de Mar (Pisaster ochraceus)Observ.
jesscubbDescripción
The most common sea star, most often known as the purple sea star, we saw at least 10 or 12 on the beach. Even the orange ones are known as purple sea stars. The spikes on sea stars' back are actually tiny scissors that help kill off anything that might try to attach itself and grow on its back. Thanks to Celso Reyes for snapping photos and sharing them with me!
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