Thursday, June 30, 2011

Death of the Cockle

Gulls feed on just about anything they can find........that's why they frequent dumps so often.  On the beaches of Puget Sound they can be found with sea stars, worms, sea urchins, crabs, clams, mussels, fish and just about anything else they can swallow.  Cockles are sturdy shelled clams that only bury themselves a few centimeters in the sand.  Gulls can see the siphons sticking up at the surface and dig them up quickly.  Once caught it's a matter of getting the cockle open by dropping it from flight until it finally breaks and is open for consumption.  While gulls don't usually share they will sometimes if it happens to be one of their offspring begging.  In the series of images below an adult gull captures a cockle, drops it till it breaks and then shares it with a juvenile gull which may be its offspring.....sharing with the crow...no way. 


Algae-Seaweed-Sea Grass

In long past years most students of biology heard the same story over and over......Every living thing depends of the energy of sunlight.   Now  we know photosynthesis is not necessary, and impossible in the deep ocean, and that chemical energy systems from the earth itself can power life.  We still don't know what percentage of life is powered by the sun and what gets energy in other ways but here on the surface it looks like photosynthesis is doing all right.....I noticed it's doing really well with my lawn (why I still have one of those I don't know).
In Puget Sound there are some 500 or more species of seaweeds, two species of sea grasses plus an unknown but large number of algal plankton species. The images below attest to the diversity of the seaweeds and phytoplankton but just scratch the surface. For a more in depth look (only about knee deep) check out the presentation Algae and Seaweeds under Buzz Links on this page.

Nori

Green Rope

Encrusting coraline algae


Surf grass

Ribbon Kelp

Feather Boa holdfast

Parasitic sea weed on red algae

Coraline Seaweed

Bubble seaweed

Stiff Stipe seaweed

Sugar Kelp

Ulva - Sea Lettuce

Japanese Eelgrass

Wireweed...Sargassum

Fucus - Rockweed

Codium - dead man's fingers

Coraline branched seaweed

Sea Sacs

Feather Boa

Succulent seaweed

Acid Kelp

Bull Kelp and 5 Rib Kelp

Red Lace Seaweed

Young Fucus - Rockweed
Fish eggs on Sargassum

Mixed Red seaweeds

Wednesday, June 22, 2011

Sashimi for Lunch

While I've posted lots of Osprey images on the blog, I'm going to be redundant and post a few more.
The Osprey is a rather unique bird, in its own family, mainly a fish eater, but will take other prey on occasion.  Males are stuck with feeding the female during courtship and incubation as well as doing some of the incubation.  Not a bad deal if you are a female.  Once the eggs hatch the young are fed regurgitated food for the first few weeks....brought by the male.  Ospreys are usually seen flying in a pattern over the water at a height of 30 to 100 feet looking for fish which they capture by plunge diving feet first.  However, at Alki beach in Seattle there is at least one Osprey that prefers to stand on a lamp post and survey the water for potential meals.  If the bird starts bobbing its head from side to side you can bet a fish has been observed and often this is a signal that flight is eminent.  The images here are form Alki beach of that bird having lunch today 6-22-11.  Sushi Forever!
Off to hunt

Great catch

success


Ah, Sashimi


Yum

always a pest

Monday, June 20, 2011

Noctiluca, the Night Light (Red Tide not)

This is the peak season for plankton blooms of certain species.  One is Noctiluca (night light) which colors the water like tomato soup.  Noctiluca is non-toxic but because of the term RED TIDE many people associate this with toxic plankton blooms known as HAB's or Harmful Algal Blooms. Noctiluca is a dinoflagellate that does not photosynthesize but preys on diatoms and other plankton.  There are two species of phytoplankton in our area that can be toxic but do not color the water.  If you collect some of the Noctiluca you can easily see the individuals with a hand lens and at night it will give of a flash of blue/green light when disturbed....or less often just randomly.  The light likely has some function.  In the Sea of Cortez I observed dolphins, sea lions and pelicans feeding on a dark night and they seemed to be keying in on the prey fish by following the glowing trail the fish made when swimming.  While dolphins and seals could use other clues to track a prey fish it is most likely that pelicans flying overhead could easily spot the light from the fish's wake......we were kayaking at the time as causing fish to swim away from the kayaks just by moving through the water.  So perhaps Noctiluca illuminates its predators allowing their predators to catch them and thus retucing the number of fish predators on Noctiluca. That would make Noctiluca very bright indeed. The biolumisence was so strong that the entire inside of the kayak was lighted by the flashing of the Noctiluca under the boats.  For more information visit:  http://www.ecy.wa.gov/programs/eap/mar_wat/mwalgae.html


Noctiluca Seahurst Park 6-17-11

Noctiluca (Night Light)

Saturday, June 18, 2011

Sand Collar Season....or More Tiny Stuff to Figure Out





The Moon Snail, Puget Sound's largest intertidal snail is currently in the middle of its breeding season (April-Sept).  Most sand and gravel beaches have egg cases (sand collars) in abundance.  The snails are separate sexes, with females growing faster and being larger than males.  Mating is rarely observed as it takes place under the sand or subtidally. Moon Snails begin to breed when about 2.2 inches in size.  Females can store sperm for up to 6 weeks before fertilizing the eggs which are mixed with a mixture of sand and glue and extruded in the form of a collar.  If you are really lucky you may witness this process by observing a collar sort of magically emerging from the sand.  The whole process takes about 20 to 40 minutes.  In all instances of witnessed egg laying I have seen the female has been upside down in the sand while laying the eggs (only dug up after eggs were laid).  The sand collar contains some 3 hundred plus thousand eggs.
Life expectancy is about 14 years maximum.
Adults feed on clams and other snails which they either drill with the rasping radula or suffocate.  Drilling is assisted with an organ that produces enzymes and hydrochloric acid to weaken the shell of the victim.
Drilled holes are countersunk which distinguishes them from holes drilled by other snails or octopuses.
Drilling rate is about 0.5mm per day and the process of eating the prey take about a day.  Moon Snails favor soft or thin shelled clams and avoid the thick shell Heart Cockles.  In turn Moon Snails is fed upon by Sunflower Stars, Red Rock Crabs, gulls, octopuses, and when small, Northern Clingfish and likely other fish.
While some people do eat Moon Snails, certain First Nations peoples of Canada did not as they were said to make the eater stupid.  Since Moon Snails feed on clams which may contain toxins that can affect brain function this seems like quite good advice...Don't eat them.

If one closely examines the concave surface of a sand collar on the beach it becomes evident that lots of things are using it to lay eggs, perhaps as cover, or feeding on the Moon Snail eggs.  Some of the items found are tiny and difficult to identify which makes it all the more interesting....if sometimes frustrating for anyone who wants to know it all.  Images below show some of the action on the collar surface.

SAND COLLAR STUFF (many of these are 1cm or less in size)

Lacuna snail on sand collar


Dove Snails on sand collar




Barnacle Eating Sea Slug on sand collar


Flat Worms


Opalescent Sea Slug


Barnacles on sand collar


Top Snail on egg mass on sand collar


Unidentified worm on sand collar


Top Snail on sand collar


Moon Snail with sand collar


Moon Snail with clam victim


Moon Snail making sand collar
Moon Snail siphon on surface collecting air


Moon Snail damaged shell from gull attack


Moon Snail drilled clam



Opalescent Sea Slug eggs


Hansine's Sea Slugs eating Opalescent Sea Slug eggs (?)
Phyllodoce williamsi  Worm eggs


Olea hanisneensis  sea slug eating Opalescent Sea
Slug eggs


Olea hanisneensis sea slug on sand collar


Lacuna snail and eggs

Opalescent Sea Slug Ho Down

Flatworm with flatworm eggs on sand collar

Unidentified snail on sand collar
Teamwork, Olea Sea Slug style
Lacuna with decaying seaweed wit
h unknown white pattern