Biology Reference
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but no one knows which archival dungeon they may have ended up in.
Until these samples are found, “we don't know how many acres of eelgrass
used to exist in the bay, or where native oyster populations used to be,”
says marine biologist Marilyn Latta of the California Coastal Conservancy
and the subtidal goals project.
Scientists aren't letting this lack of historical information hold them
back. Major surveys of current subtidal assets are either under way or
being mined for data to inform restoration.
Among the top priorities is bringing back the great meadows of eel-
grass ( Zostera marina ) that scientists suspect must have once hugged the
sandy shallows of bay margins. Expanding eelgrass beds does more than
just return a native species to the bay. “We consider eelgrass an ecosystem
engineer, a habitat builder,” Latta says. Eelgrass blades provide three-
dimensional structure to a place that consists largely of featureless mud.
Bryozoans and snails settle on and cling to the leaves, sharing space with
golden clumps of Pacific Herring eggs. The root bulbs, or rhizomes, of eel-
grass can help stabilize bottom sediments, and the long, undulating blades
have been shown, in other estuaries, to help dampen the force of waves,
ferry wakes, and other turbulence, reducing shoreline erosion. The calmer
waters within eelgrass blades offer refuge to salmon smolts, crabs, pipe-
fish, and other organisms too small or fragile to battle the currents. Mi-
grating waterfowl feed directly on eelgrass leaves, which also oxygenate
the water.
Scientists venture into the bay to conduct eelgrass research. (Jude Stalker)
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