Treasure on Cashes Ledge: An Ocean Refuge in Need of Protection

New England is as famous for its coastline as for its fish – but what lies beneath New England’s waves goes largely unseen and unremembered. One of these unknown treasures is Cashes Ledge, a 25-mile long underwater mountain range which lies 80 miles off the coasts of Massachusetts, Maine, and New Hampshire and shelters one of the most distinctive marine ecosystems in the Atlantic. But Cashes Ledge is as sensitive to human interference as it is important to ecological diversity. With limited protection against increasingly destructive fishing techniques, Cashes Ledge remains vulnerable.

Atlantic Riches

Cashes Ledge hosts a remarkable diversity of marine life, from the Atlantic wolffish and rare blue sponge to the unusual red cod. The reason for such diversity lies in the mountain range itself, whose pinnacles interrupt the primary Gulf of Maine current and create a stunning oceanographic phenomenon known as internal waves, which carry high levels of nutrients and oxygen from the sea surface to the sea floor. This unusual circulation pattern results in an incredibly productive and diverse ecosystem. Cashes Ledge boasts the deepest cold water kelp forest in the Gulf of Maine and possibly the North Atlantic and has a rich array of invertebrates including sea anemones; bright orange, red, yellow and blue sponges; horse mussels; sea stars; brittle and feather stars; sea squirts; worms and northern shrimp. Atlantic bluefin tuna can be found pursuing herring on Cashes Ledge and blue sharks are common during the warm summer months. Humpback and Northern right whales often stop off to feed on the abundant supply of plankton. Cashes Ledge is also rich in a variety of groundfish including Atlantic cod, white hake, monkfish, haddock and redfish. A variety of offshore sea birds can be found dining at Cashes, such as sooty shearwaters and Wilson’s storm-petrels.

Cashes Ledge is also a rarity in New England waters. Though the ledge’s jagged, rocky formation has protected this particular habitat from significant human interference, other areas in the Gulf of Maine have not been so lucky. Cashes Ledge is unique in the greater Gulf of Maine system because its mountains shield one of the few remaining examples of what an undisturbed and thriving ecosystem in this region could look like. It’s no wonder that scientists have used Cashes Ledge as an oceanographic research lab for decades.

Under Attack

Up until the late 1900s, the rocky seafloor surrounding the Cashes Ledge mountain range prevented fishermen from trawling the ocean floor for their catch. Today, modern fishing gear equipped with “rock-hoppers” is more effective and more destructive, and poses a serious threat to this ecological treasure beneath the waves. Certain species are especially at risk. Bottom trawling could easily wipe out certain populations of sea anemones, and scientists estimate that it would take over 200 years for the population to recover and return to the area. The kelp forests are also prone to shredding from simple fishing gear like lines, hooks, and traps, and bottom trawling could remove entire sections of the kelp forests – requiring years to recover. Any sustained damage to this delicately balanced ecosystem could last for decades or more.

Inadequate Protection

Though a portion of Cashes Ledge is currently protected by the New England Fishery Management Council (NEFMC), this protection is very limited. A part of Cashes Ledge has been designated as a habitat protection area and much of it is currently closed to fishing for cod, haddock and other groundfish. However, Cashes Ledge remains open to fishing with certain kinds of gear such as “mid-water” trawlers, large offshore lobster pots and seine nets that can seriously impact this sensitive ecosystem. Furthermore, the NEFMC is now considering modifications or elimination of these already limited protections – threatening the diversity of ocean wildlife and the unique habitat found on Cashes Ledge and the long-term health of this important and vulnerable ecosystem.

CLF Action

CLF has taken the lead in campaigning for the permanent protection of Cashes Ledge from damaging fishing gear. It is clear to us that the real value of this special place lies in preserving this treasure for ocean wildlife and as an open sea laboratory for the world’s scientists.

CLF is also committed to raising public awareness for Cashes Ledge and other ocean habitats through the recent launch of the New England Ocean Odyssey, featured earlier in this issue. This five-year program is just one of many ways CLF remains dedicated to conserving New England’s oceans.

Protecting Cashes Ledge is more than an environmental obligation – it is an opportunity. Preserving this area of natural beauty offers the chance to create another legacy for New England – one that recognizes its biodiversity and provides a thriving environment for generations to come.

Note: This article was originally pulished in Conservation Matters, CLF’s quarterly publication. Find a copy of this issues, as well as archives, here.

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Cashes Ledge

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