Buzz's Marine Life of Puget Sound: 08/01/2013

Saturday, August 31, 2013

LATE SUMMER PLANKTON

Plankton populations...both phytoplankton and zooplankton are most abundant in Spring and Summer months with an occasional peak in the Fall. Some plankton members from Seacrest pier in Elliott Bay, Puget Sound in late August. An abundance of chain diatoms, and some concentric diatoms and a scattering of zooplankton showed up in day and night plankton tows from the pier....which is usually crowded with anglers stalking the elusive salmon...Pink salmon this odd number year...perhaps 6 million will return to the Sound.

Diatoms, Copepod

Cypris stage of barnacle

Worm Larvae

Comb Jelly

Worm larva

Snail

Polychaete worm

Polychaete worm larva

Worm, Copepod

Barnacle larva

Copepods

Shrimp

Plankton

Cypris stage of barnacle

Worm Larva

Polychaete

Polychaete, copepod, snail

Amphipod

mixed plankton

Snail, clams

Sea Urchin larva

Copepods and snail

Polychaete

Tuesday, August 27, 2013

CREEPY FLIES OF THE INTERTIDAL

Known as the Barnacle Maggot (Oedoparena glauca) this small intertidal fly is big problems for the local barnacles. At low tide the adult female lays eggs on the operculum plates of the barnacle. The eggs have flanges that allow them to become lodged in cracks between the barnacle's plates. The eggs hatch within 48 hours at low tide. The fly larvae (maggots) enter the barnacle by wiggling through small gaps between the operculum plates and proceed to feed on the soft flesh of the barnacle. After feeding on the barnacle the maggot leaves and crawls to another barnacle at low tide and wedges itself into gaps in the plates....when the water returns the barnacle opens to feed and the maggot crawls in....to feed on a second barnacle and then more. After a few months the maggot pupates inside the last barnacle meal shell. In a month the maggot will mature into the adult and exit the barnacle shell at low tide. Studies have determined that as many as 20% of the acorn barnacles on a beach may contain the maggots. Golden Gardens beach in Seattle had the highest rate of predation of beaches surveyed in one study. Barnacles that contain a maggot cannot feed because their access to the outside is blocked by the maggots breathing apparatus.

THROUGH THE EELGRASS AND SARGASSUM

Late Summer communities of eelgrass and Sargassum are rich in shrimp and small invertebrates. A few passes with a plankton net demonstrates some of the diversity to be found in these habitats. Most species turn out to green, perfectly matching the eelgrass....but not so much the Sargassum. Sargassum is an introduced species of seaweed and local invertebrates have not had much time to evolve cryptic coloration to match it. In some areas of Puget Sound Sargassum has become invasive, covering large percentage of low intertidal rocky habitat to the exclusion of local seaweed species. These tiny shrimp and other crustaceans are food for a variety of fish and thus an important part of the food web.
See link to Eelgrass on this blog.

Eelgrass Isopod and Grass Shrimp

Various Shrimp

Grass Shrimp

Eelgrass

Eelgrass Isopod

Sargassum

Isopod - planktonic

Amphipod

Monday, August 19, 2013

THE GREAT SEAHURST CRITTER MOVE

This Fall the seawall at Seahurst Park beach will be removed and the upper beach returned to a natural state.
This has already been done on the South end of the beach. Removal of the seawall will benefit the marine life that utilizes the near shore area. Habitat will be returned to a more natural state that will benefit various species of fish as well as invertebrates. Seawall construction in Puget Sound in one of the major causes of loss of habitat for marine life.....you can protect your property and in the process damage and destroy the property of native species. Interestingly it seems only the rich, and clueless government agencies build seawalls, ( Enlightened City of Burien is removing previous administration mistake)....Live near the sea and wall it off.....brilliant.
On August 19th Seattle Aquarium Beach Naturalists, City of Burien, ESC Burien personnel moved a large number (thousands), of invertebrate animals from the North to the South end of the beach in hopes that they will have a greater chance of survival when the disruption of the North beach habitat takes place during the removal of the seawall.
The images below are of that extensive moving operation. Thanks to all the volunteers. In time the new North beach area will recover its species diversity and more, just as the South end has done since the seawall in that section was removed a few years ago. BACK TO NATURE.