If someone came to your town for the first time, what would you want them to know?

For Tisquantum, commonly known as Squanto, it was essential for the Pilgrims who had arrived on the Mayflower in 1620 to know about eels. That’s right, eels! Imagine visiting a new place and being told that your #1 priority was a lesson on these wriggly, slimy fish. But eels were a staple food source to the Indigenous people in Massachusetts given their abundance in the wintertime, high fat content, and the multiple methods available to catch them. The Wampanoag, the Native American people indigenous to Nantucket, had constructed spears and narrow baskets to fish for eels long before the arrival of Europeans.

So when the Pilgrims faced their first harsh winter, Squanto, a member of the Wampanoag Patuxet tribe, wanted to teach the Pilgrims about the resources surrounding them. He felt for eels lying in the mud with his feet and showed the Pilgrims how to catch them. Eels would then sustain and nourish the Indigenous people and settlers alike. Researchers would later discover that those very eels had endured a long, arduous journey to get to Massachusetts. To this day, these incredible fish still embark on this adventure, traveling hundreds of miles just to swim through our waters.

The Nantucket Eel Project

This spring we would like to invite you to learn about eels, just like the early American settlers did 400 years ago. The Nantucket Conservation Foundation is piloting the Nantucket Eel Project, a community science program that aims to understand the migratory pattern of juvenile American eels on Nantucket and promote fish conservation. Inspired by the Hudson River Eel Project, this community-focused science project is an opportunity for anyone on Nantucket to participate in valuable scientific research to monitor eel populations.

The project uses eel mops, artificial habitats that passively collect eels, to catch, count, and release glass eels in select locations around the island. Counting eels will help us understand eels’ general presence or absence and their peak time of migration on Nantucket. We will also learn where the young eels spend their time and their different pathways from the ocean to freshwater. In turn, we will get a fuller picture of our waterbodies’ health and begin to study the influence of environmental conditions, such as water temperature and weather, on eel migration.

We will take small groups of community members out to check our eel mop sites each week, where they will get hands-on experience with an ongoing research project. Volunteers will learn about American eel life history and ecology, help count the eels, and capture environmental data. We welcome people of all ages to engage in science and to learn about the creatures that live in our waters!

All About the American Eel

American eels (Anguilla rostrata) are a species of catadromous fish that migrate between coastal, brackish, and freshwater ecosystems (“catadromous” refers to fish that are born in the ocean, grow up in freshwater, and return to the ocean to spawn). The journey of an American eel begins 1000 miles from Nantucket in the Sargasso Sea, an area of the Atlantic Ocean east of Florida. Here, millions of eel eggs are released. No one has actually witnessed how eels are born in the Sargasso Sea, and even though numerous people have presented hypotheses attempting to solve this mystery (including neurologist Sigmund Freud and philosopher Aristotle), the details of their birth in the wild remain a mystery!

After their birth in the Sargasso Sea, these mysterious creatures go through their second life stage as Leptocephalus, the term for eel larvae. Leptocephali are flat and shaped like willow leaves. For about one year, these transparent larvae use ocean currents and possibly Earth’s magnetic field to find their way to the east coast of the United States.

When these baby eels find the east coast in the spring, they swim upstream to find the perfect habitat to grow up. Eels at this young stage are known as glass eels. Glass eels are appropriately named for their transparent, glass-like appearance. On their journey to freshwater, some glass eels travel through Nantucket!

These glass eels will grow into elvers, darker-colored young eels, and then golden adult “yellow eels”. Adult eels mature for up to 20 years in freshwater. After they are fully mature, they become “silver eels” and go through numerous biological changes to prepare for their journey back to the ocean. They turn a silvery color, enlarge their eyes, increase their muscle and fat stores, and use all their energy to return to their salty spawning grounds in the Sargasso Sea. After mating there, adult eels will die.

The historic presence and importance of American eels on Nantucket are well-documented: local Wampanoags and early settlers dug the Madaket ditch in the early 1660s as passage for eels and alewives. They would trap and eat eels, which were plentiful and nutritious. Today, glass eels and elvers can still be found migrating through Nantucket waterways. Adult eels can be found hibernating in ponds like Long Pond and Sesachacha Pond and swimming around the harbor and salt marshes on their journey back to the ocean. These elusive creatures played a pivotal role in the growth of Nantucket and continue to shape the island’s waterbodies.

Unfortunately, American eel stocks have been quickly declining in recent decades. Because of eels’ prevalence in the global food market (especially as an ingredient in sushi), glass eels are highly sought after to be sold to fisheries worldwide. The rise of eel aquaculture, as well as disease, exposure to pollutants, shifting ocean currents, and barriers to migration, are notable reasons for the decline of American eels. While measures to protect eels (like stricter fishing laws and removal of dams) are becoming more common, making communities aware of issues associated with eel decline is necessary to protect these vital creatures and other marine species. Understanding the numbers of glass eels and the timing of their migration can point to the effectiveness of eel conservation policies and the overall health of a waterbody.

If the fabulous, mysterious story of eels appeals (app-eels) to you and you are interested in volunteering for this project, please fill out this form: https://forms.gle/smMeBHhYuusG769c7. If you have any questions, please contact Jisun Reiner at jreiner@nantucketconservation.org or Isaac Hersh at ihersh@nantucketconservation.org.

American eel in the elver stage

Written by Jisun Reiner, Coastal Ecology Research Technician.

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