The shallows of
many soft sediment Pacific beaches hold extensive meadows of a
long green ribbon-like plant widely known as eelgrass, but also
referred to as seagrass, wigeon grass, broad leaved grass wrack,
marlee, sedge and slitch. The scientific name Zostera marina,
is derived from Greek roots meaning ‘sea girdle’ referring to the
way the stems emerge from a sheath.
Ecologically,
eelgrass meadows and its ecosystem provide important nurseries for
fish and invertebrates, and food for over 80 species of fish, 75
species of birds and hundreds of invertebrates in the North
Pacific. Eelgrass is important as shelter and food for growing
juvenile salmon (Oncorhynchus
spp.), spawning habitat for Pacific herring (Clupea
harengus),
food and growth of Dungeness crabs (Cancer
magister),
and food for brant (Branta brnicla), and many millions of
waterfowl that migrate and spend the winter along the Pacific
Coast. For this reason, the PWLF is
transplanting
eelgrass
to sites that historically had meadows.
Eelgrass
provides a support system for microscopic organisms that coat the
shoots in a brown scum by mid summer and the food of small fish
and invertebrates. The food web of many coastal animals can be
traced back to the detritus mostly from eelgrass (Phillips,
1984). The leaves slow the flow of water and promote
sedimentation that is held in place by the interlocking rhizomes
(Phillips, 1984).
Eelgrass is a
flowering plant that lives underwater. The long, narrow,
ribbon-shaped leaves can reach 2 meters in length although most
are 50 cm or shorter. New leaves emerge from an underground
creeping rhizome. Air spaces known by botanists as lacunae, in the
leaves and rhizomes provide buoyancy.
Eelgrass project aims to
harness power of plants
30 volunteers + 1,000 plants = a better inlet
References
Churchill, A.C.,
Nieves, G. & Brenowitz, A.H., 1985. Floatation and dispersal of
eelgrass seeds by gas bubbles. Estuaries, 8, 352-354.
Fishman, J.R. &
Orth, R.J., 1996. Effects of predation on Zostera marina L.
seed abundance. Journal of Experimental Marine Biology and
Ecology, 198, 11-26.
McRoy, CP. 1968.
Distribution and biogeography of Zostera marina in Alaska. Pacific
Science 22: 507.
Phillips, R.C., &
Menez, E.G., 1988. Seagrasses. Smithsonian Contributions to the
Marine Sciences, no. 34.
Reusch, T.B.H.,
Stam, W.T., & Olsen, J.C., 1998. Size and estimated age of genets
in eelgrass, Zostera marina, assessed with microsatellite
markers. Marine Biology, 133, 519-525.
Ralph PJ and
Short FT. 2002. Impact of the wasting disease pathogen,
Labyrinthula zosterae, on the photobiology of eelgrass, Zostera
marina. Mar Ecol Prog Ser 228: 265-271.
Rucklehaus, M.H.,
1998. Spatial scale of genetic structure and an indirect estimate
of gene flow in eelgrass, Zostera marina. Evolution,
52, 330-343.
Short, FT, AC
Mathieson and JI Nelson. 1986. Recurrence of the eelgrass wasting
disease at the border of
New Hampshire and
Maine, USA. Marine Ecology Progress Series 29:89-92.
Stewart, A., Pearman, D.A. & Preston, C.D., 1994. Scarce
plants in Britain. Joint Nature Conservation Committee,
Peterborough.
Tyler-Walters, H.
2007. Zostera marina. Common eelgrass. Marine Life
Information Network: Biology and Sensitivity Key Information Sub-programme
[on-line]. Plymouth: Marine Biological Association of the United
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http://www.marlin.ac.uk/species/Zosteramarina.htm
