A great white swims in a Cape Cod salt pond in 2004. Image via Mass EEA
A great white swims in a Cape Cod salt pond in 2004. Image via Mass EEA

Gearing Up for Shark Week

The Discovery Channel’s Shark Week starts in just ten days! As ocean fans around the world gear up for the annual celebration of all things shark, New Englanders are turning their eyes to the North Atlantic Great white population. It seems these days Cape Cod beachgoers can’t help but scan the ocean horizon for a dorsal fin before taking a chilly but refreshing dip.

This year’s Cape Cod shark-spotting season kicked off on June 23rd when Captain Tyler Macallister captured video footage of a great white, Carchardon carcharias, six miles southwest of Provincetown, in Cape Cod Bay. Upon seeing the shark, Macallister began recording his calm and somewhat mystical encounter with the estimated 16-to-18 foot great white. A Massachusetts Division of Marine Fisheries biologist confirmed that the fish captured on Macallister’s video camera was a great white, but that the lack of scale in the footage meant its size could not be accurately determined.

Five days after Captain Macallister’s encounter with a great white shark in Cape Cod Bay, researchers from the Atlantic White Shark Conservancy saw a great white one-quarter of a mile off of Nauset Beach, near Orleans, Cape Cod. The researchers were able to identify the fish as a 12-to-14 feet long female great white and named her “Ping.” Ping was first spotted by a spotter plane and then tracked by boat. The Atlantic White Shark Conservancy sends out both a spotter plane and boat twice a week to study Ping and other great whites.

The increase in great white shark sightings has been going on for the last decade or so, and in the Cape Cod area it’s been partially attributed to the growing gray seal, Halichoerus grypus, population around the Cape. Gray seals were previously hunted by fishermen as a precaution towards preserving fish populations that the Gray seals consume, but the seals are presently protected by the Marine Mammal Protection Act of 1972. Great white sharks prey on seals and as seal populations expand in the Cape Cod area, there appears to be a growing number of white sharks.

If you are curious where these sharks spend their days, when they are not busy stalking Cape Cod’s massive seal populations, you can track tagged sharks through Ocearch.com or through the Ocearch app. And get ready for more information on New England’s sharks as we celebrate Shark Week here at New England Ocean Odyssey!

A striped bass fisherman on Chappaquiddick. Image via John Piekos, Flickr
A striped bass fisherman on Chappaquiddick. Image via John Piekos, Flickr

Striped Bass and Forage Fish

As the summer heats up along Atlantic coast, coastal residents and visitors alike head out in boats, stake out spots on docks and bridges, or don rubber waders and forge into the waves along a beach’s breakwater. Each is armed with a long pole and a zeal for the chase. Their quarry is the striped bass, a silvery fish with trademark dark stripes running the length of its body from head to tail. The striped bass, or striper, is an anadromous fish native to the Atlantic coast of North America, and usually grows to around three and half feet. The historic abundance of the striped bass, as well as its ideal size for recreational fishing, makes it a highly valued sport fishing species. In 2004, recreational fishermen landed more than 2.5 million stripers.

Unfortunately, recent evidence indicates that this time-honored recreational fishery may be in danger of collapse. Recreational fishermen in Massachusetts reported a staggering 85% drop in striper numbers between 2006 and 2011, and Massachusetts is not alone: states up and down the coast are seeing fewer stripers, and the schools of bass that migrate up the coast from the Chesapeake Bay to Maine are thinning out. More and more fishermen are heading home empty-handed at the end of the day, and more importantly, the disappearance of the striped bass leaves a lack of an important member of the marine ecosystem and food web.

Image credit: Timothy Knepp/Wikimedia Commons

Image credit: Timothy Knepp/Wikimedia Commons

Many factors are responsible for the decline of the striper, but one is often overlooked: food. Small forage fish, including Atlantic herring and river herring, compose around 90% of the striped bass diet, and these forage fish face the pressure of a significant fishery of their own. While ignored by recreational fishermen, Atlantic herring are heavily fished by commercial fishermen, largely for use as bait in the lobster industry. In 2011, for instance, U.S. commercial fishermen harvested over 174.3 million pounds of Atlantic herring.

Recent assessments indicate that Atlantic herring are not overfished, but surveys of population levels and safe catch limits rarely take proper account of the amount of a forage fish required to feed its predator species. As a result, after the herring fishery has hauled in its 170 million pounds of fish, there may not be enough herring left to both maintain a steady herring population and provide the striped bass with sufficient prey.

River herring, meanwhile, have been depleted by years of overfishing and habitat loss due to dams. Total landings of commercially fished river herring have decreased steeply over the years: in the 1950s, over 60 million pounds of river herring were harvested by commercial fisheries throughout the US, but this number had decreased to around 2 million pounds by 2012. In response to this decline, many states have implemented moratoriums on intentional catch of river herring and have made strong efforts to remove dams and restore upstream habitat; river herring runs in many New England rivers seem to be on the rebound. But river herring are still at risk at sea, where they are caught as bycatch by the Atlantic herring and mackerel fisheries.

This scarcity of prey spells danger for the striped bass. Without sufficient forage fish, there will be fewer striped bass in the sea, and more fishermen with empty hooks.

Blue crabs. Photo via Benjamin Wilson, Flickr
Blue crabs. Photo via Benjamin Wilson, Flickr

Crab Chowder?

In 2012, northeast sea surface temperatures reached an all-time high. Many speculate that rising water temperatures have contributed to a record high catch of 126 million pounds of American lobster, Homerus americanus, in the Gulf of Maine. However, the steady rise in New England’s sea surface temperatures may have also made southern areas of New England inhospitable for lobster. In a recent interview with AccuWeater, Maine Lobstermen Association’s Patrice McCarron said, “In southern New England, Buzzard Bay, Mass., and the waters off of Rhode Island, temperatures in the Long Island Sound area have become too warm for lobsters.” Lobster catch in these areas has plummeted since the 1990s.

The warming trend in New England waters has caused alarm for local fishermen, and we’re only beginning to understand the ways climate change might affect our fisheries. While some treasured New England species may relocate father north, it’s possible that other species will move into this region and create new economic opportunities.

We’ve written before about some of these species moving north as water temperatures rise, and now we can add another to the roster—blue crabs. Although blue crabs are traditionally caught off Maryland and Virginia, fishermen in Long Island Sound have been seeing more of them lately. Some think that, in time, Long Island Sound could replicate the blue crab fishery of southern areas like Chesapeake Bay.

The blue crab, Callinectes sapidus, whose Latin name can be translated to mean “beautiful savory swimmer,” is the Maryland state crustacean and the most valuable shellfish in the mid-Atlantic region. The crabs can grow to be around 4 in long and 9 in wide, weighing around 1 pound, and reaching maturity in 12 to 18 months. The bottom-dwelling blue crab can live in a range of salinities, feeding off of crabs, claims, snails, eelgrass, sea lettuce and decayed vegetation. Blue crabs can be found all along the Atlantic Coast, with a prominent population in Chesapeake Bay presently suffering from habitat degradation and overfishing.

Could Maryland’s pride species create a new industry in New England Waters? The blue crab, caught for sale in both hard and soft shell forms, is currently sold at a market price in Maryland of $39.25 per dozen. With the growing blue crab population and a high demand market, does New England clam chowder have a new competitor on the way?

Scientists are careful to note that the long-term effects of climate change on species like blue crabs are still far too uncertain to predict the future of a fishery, but one thing is for sure—New England’s ocean is changing, and marine life is on the move.

KelpDiverBranded

The Boston Globe Visits Cashes Ledge

Categories: Action Alert | Cashes Ledge

If you picked up The Boston Globe on Sunday, you may have noticed this striking photograph of a scuba diver swimming through a lush, colorful kelp forest. The photo might have been familiar to you – it was taken by our friend Brian Skerry on Cashes Ledge, one of the most remarkable places in the Gulf of Maine.

The Globe’s front page article lays out some of the reasons why Cashes Ledge is so important - it says “the frigid waters and glacier-sculpted peaks are home to a billowy kelp forest and an abundant array of life, from multicolored anemones to cod the size of refrigerators,” notes that the ledge has been protected from trawling for over a decade, creating a sanctuary of biodiversity, and acknowledges the importance of Cashes Ledge as a breeding ground for depleted cod.

But the article also points out that Cashes Ledge is at immediate risk. This fall, the New England Fishery Management Council is considering reopening Cashes Ledge to bottom trawling. Its current favored proposal would eliminate protection for three quarters of the current closure and threaten this thriving ecosystem. The Globe asked Brian Skerry what he thought of this proposal, and he couldn’t have been more clear: “Protection must happen now if there is any hope of holding on to what remains.”

We think Cashes Ledge deserves protection. Check out the Globe’s article, and if you agree, please sign our petition asking fisheries managers to maintain full protection for Cashes Ledge and the surrounding areas.

A diver above the Heroic. Image credit: Alex Shure
A diver above the Heroic. Image credit: Alex Shure

Diving The Heroic in Stellwagen Bank National Marine Sanctuary

Categories: Guest Posters

This story and video of a wreck dive on Stellwagen Bank was shared by Alex Shure, a regular contributor to the New England Ocean Odyssey photo contest. For more information on shipwrecks on Stellwagen, see this post from Matthew Lawrence.

I recently had the opportunity to dive The Heroic, one of several shipwrecks located in Stellwagen Bank National Marine Sanctuary. The Heroic began its life as an Accentor-class coastal minesweeper built during World War II. Now, over 70 years later, its final resting place is marked by a large engine block, decaying wooden ribs, and a trail of ghostly debris scattered about an otherwise sparse sandy bottom 100 feet below the ocean surface.

We set out mid-morning from Beverly Harbor with Northern Atlantic Dive Expeditions planning for a dive at slack tide. After a remarkably calm ride out to the wreck site, 2 divers dropped into the water to tie onto a mooring recently installed by NOAA. As the first divers descended, we could still see their tanks and blue gloves 20 feet beneath the boat; this would be a good dive. I donned my gear and readied my camera with great enthusiasm for the wreck below. Steadily lowering myself along the downline deeper into the crisp water, The Heroic’s engine was visible from almost 50 feet away! As I got closer, the shadowy structure beneath gave way to a worn metal block swarmed with cunner and encrusted in hydroids. There’s not much “wreck” beyond the massive engine, but what is there has turned into an artificial reef for the local inhabitants. Shooting photos and video, I managed to burn through my bottom time before I knew it.  I waved goodbye to all of the rebreathers and reluctantly ascended back up the line looking backwards at the disappearing wreck below me.

Stellwagen exploration is the pinnacle of SCUBA in New England. Due to its location and unique underwater topography, many species of marine life call this sanctuary home. Its human visitors have the inherent adventure of offshore diving. Visibility in the sanctuary tends to be spectacular and there is a rich variety of locations, wrecks and wildlife at recreational depths. Divers get all this and can still be home in time for dinner. One can easily compare diving Stellwagen to visiting a national park above water. It is a place that deserves our respect, admiration and perhaps most importantly, our protection.