Favella and Heterosigma
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A Movable Feast

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Categories: Creature Features

When you think about grazing, you picture a big mammal with hooves eating a helpless plant – placidly chewing and digesting, right? Well, there’s another kind of grazing that is much more dynamic. Researchers at the University of Rhode Island have, for the first time known to science, discovered a plant that “runs away” to avoid being munched. The tiny Heterosigma akashiwo you see above on the right, not only makes tracks when predators like the Favella favella are after it (the big, mouthy guy on the left), but it will even avoid areas where there used to be predators, but no longer are. They are, in effect, fleeing the scent of danger.

Before you stand up and cheer for the little guy, you should know that this particular plant is one of the “red tide” phytoplankton that can cause major fish kills when it blooms. Dr. Susanne Menden-Deuer, an oceanography professor who studies the plankton at the University of Rhode Island, speculates that its ability to flee may be one of the mechanisms that allow Heterosigma to grow prolifically enough to kill fish. The plant, a type of algae, will take refuge in areas with lowered salinity – places where its predators cannot survive. As the algae move into these areas of refuge, they are free to reproduce with little to check their population explosion.

These harmful algal blooms can cause major devastation and millions of dollars in economic damage to fisheries – killing not only finfish like salmon and herring, but also harming oysters, copepods, and sea urchins.

Usually, though, Heterosigma are not harmful at all, blooming only occasionally in spring and fall. In fact, they provide many benefits to us – they are an important food source at the bottom of our productive ocean food chain. Not only that, but phytoplankton are responsible for giving us the oxygen in half the air we breathe.

Menden-Deuer plans to conduct further research to find out what the connections are between the fleeing behavior and harmful algal blooms, and if other plants might be up to this evasive behavior.

Photo credit: Elizabeth Harvey (URI-GSO). Digital enhancement by Cynthia
Beth Rubin (RISD).

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Squid Pair Attaching Egg Case To Cluster
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Announcing Our September Photo Contest Winner!

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Categories: Photo Contest

Congratulations to J.R. Cummings, who captured this month’s winning photo, “Squid Pair Attaching Egg Case to Cluster”, off the coast of Rockport, MA. We love the way this photo captures a critical moment in the life cycle of these animals against a striking black background.

Longfin squid are common in New England inshore waters and an important species for both fishermen and scientists. The squid have a short lifespan and the population turns over completely in six to eight months, so the fishery can handle relatively strong fishing pressure. Regulators have divided the squid quota across three seasons so the fishery can operate year-round.

Longfin squid also serve as a perfect test species for scientists studying the nervous system. Their chromatophores, the color-producing cells that allow them to actively camouflage themselves like ocean chameleons, also have an interesting response when the squid’s skin is stimulated by music—check out this video of the cells “dancing”:

For another beautiful photo and more information about longfin squid, see this post.

Also check out our New England Ocean Odyssey Facebook page where we’ll be posting the honorable mentions from the September photo contest over the next few days.

If you have pictures to share, there are still a few days left in our October contest!

Entering is easy! Explore New England’s oceans, take some photographs and then share them with our online community on Flickr™. All you need to do is add your photos to the New England Ocean Odyssey group and tag them “PhotoContestNEOO2012”. Find out more here.

Each month’s winner will receive a copy of Brian Skerry’s beautiful book, Ocean Soul. 

We look forward to seeing your photos!

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Whale Watch. Copyright Brian Skerry.
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Tales of Whales – Moby Dick turns 161

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Categories: Creature Features | Events/Calendar

If you haven’t read Moby Dick, or if it’s been a long time since you have – think about giving it a try. It’s a long and complicated book, but is also a very enchanting and far-ranging adventure tale. Melville talks not only of the hunt for sperm whale, but of religion, philosophy, issues of race, and so many other conditions of humanity. There’s no ignoring the fact, though, that whales were hunted, many of them nearly to extinction, in the years surrounding the publication of Moby Dick.

Our relationship with whales has changed over the decades. But we still love adventure. Happily, our whale adventures mostly take the form of observation these days, as you see in the the photograph above. Here, researchers are learning as much as they can about endangered North Atlantic right whales in order to help save them. Not just for scientists, whale watching is a multi-billion dollar industry globally. Hopefully, all this curiosity about whales will motivate us to figure out how to help them thrive as our oceans change – becoming warmer, saltier, and more acidic. This may be our ultimate adventure tale.

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Red Cod on Cashes Ledge. By Brian Skerry.
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Seafood for Thought: Fish Need Homes Too

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Categories: CLF Scoop | Creature Features

Note: This blog was originally posted by our friends at One World One Ocean as part of their National Sustainable Seafood Month Campaign. 

When you buy a piece of cod, do you wonder how many are left in the ocean? Are you curious about what kind of gear was used to catch the fish? Gillnets? Hooks? Or, maybe it was a bottom trawler? Do you consider a different choice – maybe there is a more sustainable fish to buy?

These are important questions to ask, but there’s something more basic to consider as well. Where do these fish live? What essential requirements do these animals have to survive and thrive in the ocean?

Figuring out what “sustainable seafood” means is a familiar dilemma for New Englanders. We have some of the most productive fisheries in the world, but we also have some of the most heavily fished areas in the world. New Englanders work very hard to manage our fisheries, and there is much we are still learning. Yet, there is one simple fact that scientists and many fishermen are very confident about – if fish don’t have healthy habitat, then we don’t have fish.

We have some very special ocean places in New England. Cashes Ledge, an underwater mountain range about 80 miles off the coast of Maine, is home to the deepest and largest continuous kelp forest in all offshore waters along the US east coast. Stretching 22 miles long and 17 miles wide, Cashes Ledge provides food and shelter to an enormous diversity of creatures – from bottom-dwelling tube worms and sponges to endangered North Atlantic right whales and highly migratory blue sharks and Atlantic bluefin tuna. Cashes Ledge is also rich in a variety of groundfish including Atlantic cod, white hake, monkfish, haddock, and redfish. Many kinds of offshore sea birds can be found dining here, such as sooty shearwaters and Wilson’s storm-petrels

The reason for such enormous diversity and richness 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 ecosystem. It’s no wonder that scientists have used Cashes Ledge as an oceanographic research lab for decades. It represents one of the healthiest existing marine habitats, and if more of the ocean was like it, there would be a lot more fish.

In 2002 many habitat areas in the Gulf of Maine, including Cashes Ledge, were protected from harmful bottom trawling, and these areas have begun a slow recovery. But as large reductions in the catch of cod, yellowtail flounder, and other groundfish loom in New England, there is increasing pressure to open these areas again. Places like Cashes Ledge must be protected if we are going to keep relying on our oceans to feed us and allow our ocean ecosystems to regenerate and thrive. These are irreplaceable resources, and the permanent protection of marine habitat should be a top priority for any sustainable fisheries management plan.

While it is important to think about fish in numbers – how many we catch, how big they are, how many are left – it is equally important to consider the ecosystem on a larger scale, with all its moving parts, dependent on each other for survival. When do the plankton bloom, and where? Where are the currents taking the food? Where will certain fish spawn if their favorite ledge is dragged? How will the animals adapt to our warmer, more acidic oceans?

So, as we celebrate National “Sustainable” Seafood Month, take a moment to consider where your seafood lived before it was on your plate. The ocean ecosystems that produce the oxygen in 2 out of every 3 breaths we take, regulate our climate, drive tens of billions of dollars of economic benefits, and provide us with considerable recreational activities won’t continue to produce such benefits unless we do a better job at protecting the basic components of a healthy ocean. And, while you enjoy the good decision you made about your sustainably caught fish, also be thankful that the fish came from a good home, and do what you can to help keep it that way.

Help support habit protection for special places like Cashes Ledge – click here. 

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Seals sunning on Little Salvages with Twin Lights in background
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Booming New England Seal Population Creates a Management Challenge

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Categories: Photo Contest | Talking Fish

Note: This originally ran on Talking Fish on September 18th. Photograph by Rich MacDowell as entered in the New England Ocean Odyssey photo contest. 

Congress passed the Marine Mammal Protection Act (MMPA) in 1972, forty years ago. Intended to slow the precipitous decline of marine mammal populations due to human activities, the act prohibited the killing, harassment, or excessive disturbance of marine mammals in United States waters.

For seals in New England—mainly harbor seals and gray seals—the MMPA’s protections effected a massive boom in population. Previously, the animals were considered a nuisance to fishermen and tourists. Coastal states frequently offered bounties for the killing of seals. One study estimates that between 1888 and 1962, over 100,000 seals were killed in the bounty hunt in Maine and Massachusetts alone. This mass killing was enough to trigger significant regional declines in numbers. In 1973, a survey of Maine waters counted just 5,800 harbor seals; this was likely almost the entire population at that time.

The MMPA effectively stopped the bounty hunt in its tracks, and seal numbers have risen rapidly as a result. Each female harbor seal pups once a year and survival rates in New England without predators are high. In 2001, the estimated population of harbor seals in New England had recovered to 99,340 individuals; the observed number rose by 28.7% just between 1997 and 2001. Gray seals have seen a similar increase in numbers. On Muskeget Island, just 19 adult gray seals were observed in 1994; in 2011, a census estimated between 3500 and 3800 seals. The overall observed population of gray seals in Massachusetts has increased from 5,611 to 15,756 between 1999 and 2011.

This booming, unrestricted seal population has costs.  Seals eat commercially valuable fish like cod and herring, often taking the catch right out of fishermen’s nets. They can also cause costly damage to fishing gear. In 2011, the Canadian Department of Fisheries and Oceans determined that gray seals were hindering cod stock recovery, and the minister of fisheries proposed a cull of 140,000 seals.  It’s possible they may be having a similar effect in the Gulf of Maine.

To some degree, nature is responding to this abundant, high value food source. Rising seal numbers have been linked to the apparent increase in great white sharks around Cape Cod, particularly near the large seal colonies on Muskeget and Monomoy. Sightings of great whites have increased notably in the past decade, and this summer, a swimmer off Cape Cod was attacked by one for the first time since 1936. Killer whales and other high level predators also once controlled seals in this region and may return in the future in greater numbers.

In the mean time, seals are becoming a growing political problem. A local fisherman recently pointed out the seal problem to John Bullard, the new Regional Administrator for NOAA, at an open meeting in Scituate. Tensions are also rising between the seals and local residents. Last summer, five gray seals were found shot on Cape Cod beaches.

Coming to agreement about the appropriate management response to this situation is challenging. On one hand, the rising numbers can be viewed as a remarkable success of the MMPA and a return to natural conditions. One conservation response is to argue that the seal population will start to limit itself as numbers approach carrying capacity or as recovering shark numbers or other marine predators catch up with the new abundance of prey. On the other hand, some stakeholders have called for new, direct methods to limit seal numbers, including culling. The Seal Abatement Coalition has circulated a petition calling for “an amendment or exception to the Marine Mammal Protection Act which would permit the humane dispersion of [gray] seals.”

The original text of the MMPA allows the secretary of commerce to make some exceptions to the no-take rules, taking into account “the conservation, development, and utilization of fishery resources,” provided that “the taking of such marine mammal is in accord with sound principles of resource protection and conservation.” These have included the issuance of permits for marine mammals caught incidentally by commercial fishing operations. NOAA has also previously allowed the dispersion of sea lions in California that damage fishing gear and has permitted the killing of sea lions that were eating endangered salmon in the Pacific Northwest.

Nonetheless, it is unlikely that culling of New England’s seals will be allowed.  Beachgoers like spotting these charismatic animals and seal watching tours have become popular in some coastal communities. Harbor and gray seals are not widely regarded by the public as a nuisance, unlike California sea lions. In this context, it would take an “act of god” (as one state administrator put it)—or at the very least an act of Congress—to begin culling seals in New England.  As a Chatham fisherman told NPR last month, “There’s not a congressman in his right mind that’s going to be the first one out that says, ‘Let’s go harvest seals.’” Even with fisheries, the case for seal culling is modest. A recent study suggests that even if marine mammals were completely removed from the environment, potential catch from fisheries may not be dramatically improved.

There may be technologies that act or could act to reduce seal-fishing gear interactions non-lethally. “Pingers” like those used to deter porpoises from gill nets could be used to scare seals away from fishing gear. Still, this technology could be expensive to implement and may be ineffective on seals, which are highly intelligent animals and might even become attracted to the noise over time as they learn to associate it with readily available fish.

The solutions to New England’s exploding seal populations are not obvious, but the pressure for responses is growing and will continue to build. Seals are no longer just the stuff of children’s books and aquaria exhibits; they are back in force and growing rapidly. Natural seal mortality rates will undoubtedly increase over time, but as long as people and seals are both chasing after the same scarce fish resources, soon may not be soon enough for some.

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