Zooplankton: A tiny creature with a big role in the cod crisis

One of the North Atlantic’s smallest ocean critters is making big waves in New England.

Centropages. Photo courtesy NOAA
Centropages. Photo courtesy NOAA

Over the last decade, we’ve seen the collapse of our iconic Atlantic cod fishery due to extreme overfishing. Now, a new study is showing a potentially disastrous link between the effects of climate change and the ailing species’ chance of recovery.

Warming waters are bound to be bad news for a cold water fish, but the problem goes much deeper than that, affecting the entire life cycle of the species. Some of this is due to tiny, microscopic creatures called zooplankton. So what are these little guys, and why are they so important?

Zooplankton is a categorization of a type of ocean organism that includes various species, including Pseudocalanus spp, and Centropages typicus. These two species happen to be the major food source of larval cod in the Gulf of Maine.

Zooplankton, which are usually smaller than 1/10 of an inch, play a major role in the Atlantic’s food web. When there are lots of them, things are pretty good. Young fish prey on them and grow to be healthy, adult fish.

But when there aren’t enough plankton to go around, species like Atlantic cod can suffer. When cod larvae aren’t easily able to find the food they need to grow, fewer of them make it to their first birthday.

And without lots of cod that survive to be at least 4 years old (the age at which females begin spawning), the recovery of the entire stock can stall. The stock needs larger, older, more productive females to thrive in order to have any hope for recovery.

Warming and shifting

But why would the plankton be in such short supply? This is where climate change comes in. According to NOAA, temperature changes can cause the redistribution of plankton communities. In the Gulf of Maine, scientists have found fewer plankton in the same areas where cod populations have been found to be struggling. The shifts in temperature lead to the displacement of a critical food source, making it difficult for young cod to survive.

Larval cod. Photo courtesy NOAA
Larval cod. Photo courtesy NOAA

With the Gulf of Maine is warming faster than 99% of ocean areas, this is an enormously alarming problem. More temperature changes and the shifting of plankton populations could make it even harder for New England cod populations to return to healthy, sustainable levels.

While the cod crisis is the result of many factors – but the loss of tiny zooplankton is a big problem. When considering how to best help cod stocks recover, fishery managers must take into account the effects of climate change, or else risk the total collapse of the species.

BOO! Happy Halloween from this spooky species, the Monkfish


Photo courtesy Mike Beauregard via Wikimedia Commons

In honor of Halloween, we’ve decided to highlight one of the more creepy looking fish that can be found in the waters off of New England. The monkfish (Lophius americanus), also known as goose-fish, anglerfish, and sea-devil, is considered a delicacy abroad, but until recently has been overlooked in America, perhaps due to its obtrusive appearance.

The monkfish is highly recognizable, with its brown, tadpole-shaped body, and its gaping, fang-filled mouth. These eerie-looking fish can be found from Newfoundland to Georges Bank, and all the way down to North Carolina. They prefer to dwell on the sandy or muddy ocean-floor, where they feed on a variety of small lobsters, fish, and eels. Monkfish are typically found at depths of 230-330 feet, but have been caught in waters as deep as 2,700 feet; they have also been known to occasionally rise to the surface and consume small, unsuspecting birds. Females can grow up to forty inches and males up to thirty-five inches, and both can weigh up to seventy pounds. The average market size fish is around seventeen to twenty inches long.

Before the 1960s, monkfish were considered to be undesirable bycatch. However, in the wake of the collapse of the New England Atlantic Cod fishery, the monkfish has slowly started to become a more common alternative, in part due to awareness campaigns about “underutilized species” in New England. Now, monkfish is caught to supply both international and domestic demand – the tail is prized for its firm texture and sweet taste, perfect for baking and poaching, and the liver is used in Japanese sushi.

In fact, in the last two decades, fishing has increased so dramatically that monkfish stocks started to decline. Landings peaked in 1997 at sixty million pounds. However, thanks to the quick action of both the United States and Canada, a management plan was put in place and the stock population started to increase and stabilize. Landings now average around thirty-five million pounds annually. Monkfish are caught using trawls, gillnets, and dredges. The fishery is managed by the National Oceanic and Atmospheric Administration (NOAA), the New England Regional Fishery Management Council, and the Mid-Atlantic Fishery Management Council. These organizations do not impose annual catch limits, but do limit daily catches as well as limit access to the fishery. Nevertheless, the catch is still exceeding target catch levels in certain locations.

Current threats to monkfish are common among New England marine species: warming temperatures, ocean acidification, and habitat loss.

NOAA Fishwatch considers monkfish to be well managed and a “smart seafood choice” – however, it is still vulnerable, and the fishery should continue to be closely monitored, or it could suffer the same fate as other groundfish fisheries.

So, if you are looking for a spooky-themed seafood dish for this weekend’s festivities, it might be time to give monkfish a try… It would also make one unique Halloween costume!

Celebrating New England Lobsters on National Lobster Day

Cashes Ledge Lobster
A lobster at Cashes Ledge. Photo courtesy Brett Seymour/CLF

If there’s one thing we can be sure of, it’s that New Englanders love lobster. It’s weaved into our culture and history, and it’s unimaginable to think of New England without this famed summer seafood.

Few know that lobsters were once so plentiful in New England that Native Americans used them as fertilizer for their fields, and as bait for fishing. And before trapping was common, “catching” a lobster meant picking one up along the shoreline!

During World War II, lobster was viewed as a delicacy, so it wasn’t rationed like other food sources. Lobster meat filled a demand for protein-rich sources, and continued to increase in popularity in post-war years, which encouraged more people to join the industry.

Popular ever since, now when most people are asked what comes to mind when they think of New England, seafood – especially lobster – is typically at the top of the list.

An industry under threat

We love our New England lobster, but there’s evidence suggesting they’re in danger of moving away from their longtime home. That’s because lobster is under threat from climate change, the effects of which can already be seen on this particular species.

The Gulf of Maine is warming faster than 99% of ocean areas. Until last winter’s uncharacteristically cold temperatures, the prior few years saw an increase in catchable lobster – as the warmer temperatures cause them to molt early, and they move toward inshore waters after molting. However, continued warming will ultimately encourage the lobsters to move north to find colder waters, where they spend the majority of their time.

This is already happening in southern New England, where the industry is already suffering, seeing lobsters migrating northward.

And we’re still learning about the potential for damage caused by ocean acidification, as well as how lobsters may be affected by an increase in colder than usual New England winters.

As we celebrate one of New England’s iconic species on National Lobster Day, let’s remember that slowing down climate change is an important priority for ensuring that future generations can enjoy not Canadian or Icelandic lobster, but New England lobster. Click here to support Conservation Law Foundation’s efforts on fighting climate change.

Save the Whales: Create marine protected areas

“Save the Whales” was a popular cry in the late 1980s to ban commercial whaling worldwide. While progress has certainly been made, this phrase should not be relegated to a dated trope: Many whale populations are still struggling, including our New England’s own North Atlantic Right Whale.

Found from Nova Scotia to Florida, the area from the Gulf of Maine to Cape Cod is essential for this endangered species. Its name comes from the idea that it was the “right” whale to hunt – it was slow-moving and had lots of oil and baleen. Commercial whaling for this species ended in 1935, but these New England whales are still rebuilding.

Zach Klyver, a naturalist with Bar Harbor Whale Watch, has conducted surveys commissioned by the New England Aquarium on whales in the Cashes Ledge Area in the Gulf of Maine. During these winter surveys, Klyer says he saw many right whales breeching just before sunset. According to Klyver, “Cashes Ledge is a significant place for right whales year-round.”

Marine protected areas allow species like the right whale to find refuge from human threats and to thrive. Dr. Scott Kraus, marine scientist at the New England Aquarium, says that the reason Cashes Ledge in particular is important is because “The landscape underwater has a lot of steep angles and hills, so that any water currents rush to the surface. This makes plankton bloom, and it brings fish in – it’s a great restaurant for whales in New England.”

Thriving whale populations also help boost tourism during the popular whale-watching season—more whales means more opportunities for sightseeing. Tourism in New England provides 230,000 jobs and brings in $16 billion – more than all the fisheries, forestry, and agriculture industries combined – making it the life blood of New England’s economy.

An expanding coalition is working to establish permanent protections for Cashes Ledge and another important New England area, the Coral Canyons and Seamounts, by calling on President Obama to establish the first Marine National Monument in the Atlantic. Join the conversation on Twitter: Tweet with #SaveOceanTreasures


Fish Friday Finale

Over the course of the summer, we’ve been showcasing some of the fish (and other species) that make their home in New England’s ocean waters: Some of these species are endangered and in need of protections (see #SaveOceanTreasures), and some are considered underutilized because of low demand. Others are just fun or silly (or silly-looking!).

One of the main goals of the New England Ocean Odyssey project is to unlock the mysteries of the ocean: What creatures live there? What important habitats are out there, and why should we care about them? We want to let people know about this whole other world that exists just beyond what we can see. To that end, we hope you’ve found this series fun and informative, and we look forward to providing you with more “Creature Features” in the future!!

Now, in case you missed any – a Fish Friday Wrap-Up:

Atlantic_Salmon_Credit_TimothyKnepp_FWSSOS: Save Our (Atlantic) Salmon!


The Basking Shark: A Modern Marine Mystery Basking Shark


The Atlantic Wolffish – Antifreeze Included 1.13_Matthew_Lawrence



Silver Hake: A Scrumptious and Sustainable Cod SubstituteSilverHake



Hooded seal The Hooded Seal: Battling Foes with a Bladder Nose!


Atlantic Halibut – Don’t Let the Googly Eyes Fool YouAtlanticHalibut


Acadian Redfish: Consume Regularly for a Healthy OceanAcadian_Redfish_Credit_NOAA_Fishwatch



20091114 AT SEA : FRENCH POLYNESIA A juvenile oceaninc white tip shark swims past an apparently abandoned fish aggregating device (FAD) made of fishing nets, buoys and bamboo sticks, floats at sea in French Polynesian Waters off the Marquesas Islands at LAT 09:46.3 SOUTH / LONG 142 38.4 WEST. Greenpeace is calling for a global ban on FADs. GREENPEACE / ALEX HOFFORD Atlantic Spiny Dogfish, the Comeback Shark 


A Rollercoaster of Demand for Atlantic Pollock Atlantic Pollock


Fish Friday: A Rollercoaster of Demand for Atlantic Pollock

Atlantic PollockFriday, Friday, gotta read Fish (on) Friday. Last week, we featured a shark, and before that, a pretty little rosefish. But today, we have a real fish’s fish for you – a greenish, scaly, schooling creature with barbels and a classic fishy silhouette – the Atlantic pollock.

You are probably very familiar with this fish’s close relative, the cod, and you may even know about the Alaskan pollock – one of the largest, most valuable fisheries in the world. But have you ever heard of the Atlantic pollock?

Pollachius virens range. Image via NOAA Fishwatch.PollockGOM

To be even more specific, we’re talking about Pollachius virens, the species of pollock living in the Northwestern Atlantic (not to be confused with Pollachius pollachius, the Eastern Atlantic species). These guys are most common on the western Scotian Shelf, on Georges Bank, and in the Gulf of Maine (see map). Juveniles feed on crustaceans and small fish, while adults feed primarily on other fish. They may grow up to 3.5 feet long and live up to 23 years.

Ignored, Overfished, and then Ignored Once Again

Before the 1980s, Atlantic pollock were primarily harvested as bycatch. However, demand grew steadily, peaking in 1986. By 1994, the stock crashed due to overfishing. Strict management regulations were quickly put in place, and the population rebounded. By 2010, the Georges Bank and Gulf of Maine pollock stocks were 115% above target population levels. Today, the species is managed under the Northeast Multispecies Fishery Management Plan.

Much like the Acadian redfish and Atlantic spiny dogfish, the recovery of this species was a mega management victory. But the ecological recovery of Atlantic pollock came at a price – while the stocks were rebuilding, the Atlantic pollock fishery was largely ignored. So much so that even today, it is an afterthought compared to the Gulf of Maine cod, haddock, and flounder fisheries.

In 2014, only 26% of the potential harvest was actually caught. Why are we heavily overfishing some fish populations, while ignoring healthy Atlantic pollock stocks? Because there isn’t demand for Atlantic pollock – at least, not yet. As with three of our previously featured underutilized species (silver hake, Acadian redfish, and Atlantic spiny dogfish), the Gulf of Maine Research Institute’s Out of the Blue campaign is working to create consumer support for sustainable seafood, as well as incentivize restaurants to use these underappreciated species. Check out their Seafood Dining Series to sample local, responsibly harvested seafood masterpieces, or try whipping up some Atlantic pollock for yourself with these cooking tips!

Bon Appétit!

While landings peak from November to January, Atlantic pollock are typically available year-round. They’re very low in saturated fat and are a great source of protein, vitamin B12, phosphorus, and selenium. You can find them as whole, as fillets, and as fresh, frozen, or smoked steaks – but make sure you’re buying Atlantic pollock, not Alaskan pollock, for a local meal! The Alaskan pollock fishery is well-managed and stocks are not overfished, but eating fish from the Pacific won’t help incentivize Gulf of Maine fishermen to harvest underutilized species. We need to build a demand for sustainable seafood from our own backyard!

The firm, white meat of Alantic pollock has a sweet, delicate flavor and is great for dishes such as Atlantic pollock in cartoccio with preserved blood orange (basically an easy, delicious, fancy fish cooked in a bag). Or if you’re a fish sandwich kind of person, you could try an island spiced pollock sandwich with sautéed spinach, tomato, avocado and cherry pepper aioli. Yum!

Hungry yet? What are you waiting for? Make room for Atlantic Pollock!

Fish Friday: Atlantic Spiny Dogfish, the Comeback Shark

On this marvelous Friday, we bring to our fish-loving friends a miraculous fish – the Atlantic spiny dogfish. Spiny Dogfish

This groundfish (which…SURPRISE! is actually a shark) suffered a serious population decline in the 1990s, but stocks have since recovered. In fact, the dogfish is now the largest shark fishery in the U.S.

Small, but Spiny

Spiny dogfish have slim bodies and a narrow pointed snout. They are gray in color, with white bottoms, but no chance you’ll mistake these guys for great whites. Dogfish have characteristic white spots and only grow to 4 feet (females) and 3.3 feet (males).

Typical of any groundfish, spiny dogfish swim in large schools near bottom habitat. They prefer temperate areas (Nova Scotia to Cape Hatteras) and will migrate seasonally as water temperature changes, moving north in the spring and summer months and south in the fall and winter. Some brave dogfish will take on the winter in the north, but will move to offshore waters.

Spiny dogfish are opportunistic feeders. Their preferred meal choice changes as they grow larger: the kids menu features primarily crustaceans, but larger dogfish take on jellies, squid, and schooling fish. And these sharks are more than just teeth – they have venomous spines on their dorsal fins! Unfortunately for the dogfish, the spines don’t seem to deter predators. Cod, red hake, goosefish, other spiny dogfish and larger sharks, seals, and orcas often make the dinner out of the dogfish.

An Attractive Female Fish
Spiny Dogfish
Dogfish grow slowly and reach sexual maturity later in life, females at 12 years and males at 6 years. They spawn offshore in winter months, and females give birth to live young, averaging 6 pups per litter.

Female dogfish are larger than males (growing to 4 feet versus 3.3 feet), which make them an attractive catch for fishermen. This, combined with late sexual maturity, makes populations vulnerable to overfishing. Between 1987 and 1996, when traditional groundfish stocks ran low and international demand for dogfish increased, fishermen began targeting these larger females. It only took about ten years for populations to decline to minimum sustainable levels in 1998.

A Return to Glory

Once declared overfished, New England and Mid-Atlantic fishery managers began work on a Spiny Dogfish Fishery Management Plan (FMP), which was implemented in 2000. The Mid-Atlantic Fishery Management Council now leads on dogfish management actions, and in 2003 the Atlantic States Marine Fisheries Commission issued an interstate FMP to accompany the original plan. Talk about fisheries management cooperation!

The FMP implemented in 2000 established low annual and per trip catch limits, which were effective. Although the species is still victim to trawler bycatch, NOAA Fisheries declared spiny dogfish populations rebuilt in 2010, and catch limits were increased.

Fishermen use longline, hand lines, and gillnets to catch the species. 28 million pounds of Atlantic spiny dogfish were harvested in 2012, a catch that was valued at $5 million.

SHARK and chips?

With all of this talk about the dogfish fishery, you might be wondering – who even buys and eats dogfish (a shark)?!

Massachusetts fishermen landed over half of the 2012 dogfish catch, but this abundant shark still remains an underutilized species in the U.S. The demand for U.S. dogfish comes from Europe where the species is used in common dishes such as British fish and chips and German shillerlocken, a beer garden snack.

Efforts are underway in the U.S. to promote dogfish consumption. GMRI’s Out of the Blue campaign hosted a Cape Shark Week this past July. They partnered with eight restaurants throughout New England to showcase the delicious species and build consumer awareness.

So what does dogfish taste like?! It’s a firm, flaky white meat with a sweet, mild flavor (think dogfish in tomato and citrus). Are we making you hungry yet?! What about roasted dogfish with red curry and bok choy or grilled dogfish kebabs with couscous and salsa verde?

And even more good news: dogfish is available year round and is a great low-fat source of protein, as well as selenium and vitamins B6 and B12!

Fish Friday: Acadian Redfish – Consume Regularly for a Healthy Ocean

A Floral Fish?
I must admit, it was a lovely little nickname of the Acadian redfish (Sebastes fasciatus) that drew me to feature this cool creature – “rosefish.” While they most certainly do not stay true to this name in odor, they make up for it in color. Redfish range from pale yellow to bright red, much like their floral namesake.
Acadian Redfish
Acadian redfish – a rosey-hued deep sea dweller. Image via NOAA Fishwatch.

You may also recognize redfish by the name “ocean perch,” but they are not, in fact, perch (genus Perca); they are actually rockfish (genus Sebastes). Literally, these guys love rocks…and mud, and clay. Basically, they love bottom substrates.

In the Gulf of Maine, redfish most commonly live at depths up to 975 feet. Juveniles are often found hanging out around deep sea corals such as Primnoa. The corals serve as nursery grounds that provide shelter and an array of delicious invertebrates for the juveniles to snack on. As they mature, they begin to feed on larger invertebrates and small fish.
Redfish and Primnoa
A redfish hangs out under some Primnoa. Image via NOAA Fishwatch.

Military-Grade Protein

Unlike cod and haddock, redfish weren’t always a crowd favorite. But in the 1930s, food freezing technology was developed, and the market for frozen redfish quickly arose. The fish were readily abundant and easily distributed in frozen form, making them a perfect source of protein for the U.S. military in the 1940s and 1950s. Unfortunately, by the mid-1980s, heavily-exploited redfish stocks reached an all-time low.

Around this time, scientists determined that redfish have sensitive biological characteristics that make them particularly vulnerable to overfishing: slow growth rates, low reproductive rates, late sexual maturity, and long lifespans. Taking these factors into consideration, fishery managers imposed strict regulations on fishing gear, catch limits, and fishing areas for Acadian redfish. By June 2012, the stock was declared fully recovered. The population is now estimated to be at 32% above the target population – a true fisheries management success story!

Changing Gear and Changing Mindsets

Redfish populations may be thriving, but neither fishermen nor consumers have been paying them much attention. In 2010, only about 23% of the total allowable Gulf of Maine total allowable catch was harvested. Add to that the fact that most of the GOM harvest was used as lobster bait, and you have a seriously underutilized species on your hands!

The Northeast Fisheries Science Center’s Cooperative Research took action to help the redfish fishery reach its full potential. Fishermen joined government officials, scientists and researchers, and other industry leaders for REDNET, a collaborative effort to “efficiently harvest the redfish resource in the Gulf of Maine while avoiding non-target catch” (NOAA Fishwatch).

Redfish grow up to 20 inches, but they have a flattened shape. Although still a victim to bycatch, their narrow bodies sometimes allow them to slip through standard 6.5 inch mesh groundfish nets. In March 2011, REDNET partners tested a 4.5 inch mesh on five commercial trips in the Gulf of Maine. According to the April 2012 Completion Report, the smaller mesh was extremely effective; the trips harvested commercial levels of redfish without significant levels of bycatch, which had been the fear.

After the successful demonstration of the 4.5 inch mesh, the New England Fishery Management Council (NEFMC) passed a rule allowing trawlers to use the smaller mesh only when targeting redfish (catch must be 80 percent redfish). With regulations in place, fishermen just need the incentive to commercially harvest redfish; they need to see that there is a market for their catch, that consumers are demanding the species.


Remember how we talked about silver hake, another underappreciated GOM species? How the Gulf of Maine Research Institute (GMRI) is running Out of the Blue to elevate consumer awareness and make under-loved GOM species profitable for fishermen to target? The Acadian redfish is in the same boat (pun intended!). GMRI is working with chefs, restaurants, and institutions to rebuild demand and create a market for redfish. Think: providing sustainable seafood information to culinary partners, rewarding restaurants that practice marine resource stewardship, and hosting a Seafood Dining Series to educate consumers. They want to give overfished populations, such as cod, a break by promoting more abundant alternatives. Maple miso redfish, anyone?

It keeps getting better. Acadian redfish are available year round; they’re low in saturated fat, calories, and mercury; and they’re good sources of calcium, protein, phosphorus, selenium, niacin, vitamin B6, and vitamin B12. So next time you’re craving fish tacos, make them spicy redfish tacos a delicious choice that’s good for the ocean and good for you.