Sound Facts

The Value of Underwater Plants

Over a century ago, eelgrass meadows could be found all around coastal Long Island Sound. Today it mainly exists in some of eastern Connecticut’s bays, coves, and harbors and the North Fork of Long Island, Plum Island, and around Fishers Island in New York.

An eelgrass bed off of Fishers Island, N.Y. Photo: CCE Suffolk County Marine Program.
An eelgrass bed off of Fishers Island. Photo by Cornell Cooperative Extension Suffolk County Marine Program.

Eelgrass, Zostera marina, is found on sandy bottoms or in estuaries, usually submerged or partially floating during low tide. Most eelgrass are perennial. They have long, bright green, ribbon-like leaves, the width of which are about 0.4 inches. Short stems grow up from extensive, white branching rhizomes. The flowers are enclosed in the sheaths of the leaf bases; the fruits are bladdery and can float.

Why is Eelgrass Important

Eelgrass provides important ecosystem services. Here are examples:

  • Serves as important nursery habitat, refuge from predators, and food source for key recreational and commercial fish species.
  • Prevents shoreline erosion by stabilizing sediment and reducing the intensity of wave impacts.
  • Captures and stores carbon (i.e., carbon sequestration or known as blue carbon  [PDF] )
  • Removes excess nitrogen from the water column (i.e., denitrification)
Sunlight penetrating the surface to the seafloor is needed for eelgrass to grow. Photo by Cornell Cooperative Extension Suffolk County Marine Program.
Sunlight penetrating the surface to the seafloor is needed for eelgrass to grow. Photo by Cornell Cooperative Extension Suffolk County Marine Program.

Restoring Eelgrass

Eelgrass needs clean water, sunlight, and the right sediment to grow, along with optimum water temperatures. Because of its importance for the health of the Sound and its shoreline, government agencies and environmental organizations are trying to restore eelgrass. But it’s challenging to have all the components in place for successful restoration. The Long Island Sound Study has a strategy to to protect existing eelgrass meadows and create opportunities to increases their extent. Check out the following web links to learn more:

  • Long Island Sound Eelgrass Management Strategy (see report in the media center)
  • Eelgrass Extent (see Ecosystem Targets and Supporting Indicators microsite)
  • Embayment Water Clarity (see Ecosystem Targets and Supporting Indicators microsite)

What You Can Do!

In the meantime, you can help out to protect our eelgrass in Long Island Sound (and other estuaries). Here are some actions you can do:

  • Consider not using or reducing fertilizer to lawns as this will decrease nutrients to the Sound.
  • Dispose and recycle trash properly to keep marine debris out of the waters.
  • Boat responsibly! Slow down or trim up your engine‚Äôs prop in shallow areas with eelgrass.
  • Volunteer for restoration activities. Check out the Long Island Sound Study Facebook and Instagram account (@lisoundstudy) to keep up with upcoming events.
  • Raise awareness and educate your peers!! Spread the word about the importance of seagrass to continue to better protect and restore Long Island Sound.

Dive into Eelgrass with a Story Map!

Photo of three EPA scientists, left to right, Cayla Sullivan, Evelyn Spencer, and Jean Brochi (with flag), helping to establish a seagrass monitoring site off Fishers Island in August 2023. Photo by Katie Lund, CT NERR.
Photo of three EPA scientists, left to right, Cayla Sullivan, Evelyn Spencer, and Jean Brochi (with flag), helping to establish a seagrass monitoring site off Fishers Island in August 2023. Photo by Katie Lund, CT NERR.

Cayla Sullivan, one of the three divers exploring eelgrass off Fishers Island in this photo, has created a Story Map in ArcGIS that covers a lot of information about the history of eelgrass in the Sound, where it can be found today, and its importance. It’s available on the ArcGIS website.

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