Eelgrass Stella Wenstob | FJORD CONTRIBUTOR
FJORD
adaptations, called 'osmoregulation,' that allow it to survive in
The mud squelches and the morning mist hangs heavy over the low tide. The beach beckons with its early riser buzz. Today’s low tide story is about eelgrass — a green plant that inhabits the Pacific intertidal from Baja to Alaska and makes up some of the most important estuarine environments. Zostera marina as the biologists call it is one species of a genus of sea grasses that exist in various forms worldwide. It consists of a thin (0.4 inch) grass-like frond, which can grow to lengths of 2-5 feet. Unlike other so called ‘seaweeds,’ eelgrass has a true root system (rhizomes), which anchors the plant and provides a path for nutrients that it extracts from the muddy or sandy substrate and also serves to secure its home beach against erosion. Like the land based strawberry plant or clover, eelgrass reproduces through the branching out of this rhizome system. Additionally, eelgrass is a true flowering plant and also reproduces with the production of small, buoyant seeds that disperse great distances in the water.
"Eelgrass has specific
Eelgrass typically grows in a sandy-muddy sediment in the low-tide of semi-protected beaches. The depth varies, it begins at the tidal section of the beach— low enough to avoid the arid, midday tides of the summer —and only so deep into the sub-tidal zone as its photosynthetic fronds can tolerate (like many land plants, it does not like the shade). According to genomic research (Olsen et. al 2016), eelgrass' evolutionary ancestor was a land plant that acclimatized to the ocean environment. Eelgrass has specific adaptations, osmoregulation, that allow it to survive in the see-saw salt-levels of an estuarine environment- where the 16
the see-saw salt-levels of an estuarine environment." tide rises and falls exposing the grass to the air and also varying amounts of fresh and salt-water. Early coastal inhabitants utilized eel grass as a food source. The rhizomes were roasted in pit-cooks to flavor meat such as deer, porpoise and seal. It was dried and eaten in the winter. Northern tribes had special feasts for the eelgrass where the entire plant was eaten. Eelgrass is also an important spawning place for herring— with the roe (eggs) attaching to the fronds of the eelgrass. Since eelgrass beds act as an key nursery for so many marine species, including many
