Why do we care about seagrass?
Seagrass helps keep our oceans healthy! It provides food and shelter for fish, crabs, and other sea animals, and it also helps protect coastlines from erosion by holding the sand in place with its roots. Seagrass even helps fight climate change by taking in carbon dioxide from the water, just like trees do on land. Without seagrass, many marine animals would lose their homes and our ocean and planet would be out of balance.
Is there seagrass in Massachusetts?
Yes! In Massachusetts, the only type of seagrass you’ll find is eelgrass (Zostera marina). It's a long, ribbon-like plant that grows in shallow, salty coastal waters and forms underwater meadows that are really important for fish, shellfish, and water quality. Around the world, there are about 60 different species of seagrass, living in coastal areas from the tropics to the Arctic.
Researchers at Northeastern University are exploring the community and ecology and genetic diversity of seagrass populations in the Gulf of Maine and around the world, focusing on marine sustainability, conservation, and restoration. This research aims to bridge the "science-practice gap" by demonstrating how biodiversity principles can enhance ecosystem function in restoration projects.
Dr. Randall Hughes, Professor at Northeastern University, spoke with WBUR about the importance of eelgrass and the ongoing work to protect it:
Dr. Randall Hughes, Professor at Northeastern University Marine Science Center, collaborated on this database of eelgrass restoration methods and ongoing projects around the state.
Genetic diversity in seagrass can help plants recover from disturbances, similar to how having different species helps ecosystems.
This 2-year field experiment tested how seagrass with different genetics responds to various levels of disruption.
The scientists found that having diverse genetics helped seagrass recover from the most severe disturbance, though single-type plots did better when left undisturbed.
When an unexpected algae bloom damaged their plots, the genetically diverse plots lost fewer plants and maintained this advantage for a year, ending with more plants and biomass. This benefit came from both different plant types using resources differently and one particularly successful plant type thriving in all conditions.
The study concludes that genetic diversity affects recovery from disturbances through multiple mechanisms that depend on specific plant traits and what you're measuring.
Scientists studied seagrass wasting disease (caused by the parasite Labyrinthula zosterae) across a wide geographic range in both the Atlantic and Pacific oceans to understand what causes it to spread.
In the Pacific Ocean, seagrass size and nitrogen content were the most important factors affecting disease prevalence, while in the Atlantic Ocean, seagrass size and density mattered most.
Temperature was also an important factor influencing disease levels, especially in the Pacific Ocean.
The study found that the relationships between disease and various factors sometimes differed from what smaller lab experiments had shown, suggesting that local conditions can change how disease spreads.
This research helps us understand that both the characteristics of the host plant and environmental conditions affect how diseases interact with seagrass, which is important for conservation efforts.
Click the link below to explore the online aquarium full of seagrass species:
https://seagrassexplorer.itch.io/seagrass-explorer
This game was designed by Gwendolyn McManus, Undergraduate Student, Northeastern University, in association with Dr. Randall Hughes, Professor, Northeastern University, and Dr. Torrance Hanley, Assistant Professor, Sacred Heart University
Seagrass Explorer: Student Worksheet
Use the worksheet linked above to guide students through exploring the website.
Teacher Answer Key provided on Page 2.
Materials:
popsicle sticks or pipecleaners
coloring pencils or crayons
seagrass bed coloring sheet (linked online here)
For the youngest students, use a coloring sheet and a miniature quadrat (pipecleaners or popsicle sticks glued together). Students can color their sheet, learn the species listed, and then use their miniquadrat to 'sample' areas of the sheet. Who will find a flounder in their quadrat? Who will find 2 species of crabs?
Materials:
clipboards & pencils
ruler or transect
printed seagrass quadrats: (linked online here)
OR:
student worksheets: (linked online here)
Students will learn how scientists monitor seagrass habitats and track percentage cover overtime, and will practice using a quadrat to measure percentage cover of seagrass.
After learning about endangered eelgrass in their own community, a group of Swampscott high schoolers started a campaign to establish eelgrass as the official marine flora of the Commonwealth.
Learn more and sign their petition: linked online here
Division of Marine Fisheries is working with boating and fishing communities to encourage moorings that are less damaging to seagrass beds offshore.
DMF Literature: linked online here
Thanks for being a Seagrass Explorer!
This project was created by the Hughes Lab team at Northeastern University's Marine Science Center and supported in part by funding from the National Science Foundation and MassBays National Estuary Partnership.