Science

February 18, 2015 — The great white sharks that swim off Cape shores are not only older than we once thought, but also grow more slowly and become sexually mature at a much later date than previously believed. This makes their comeback story more remarkable, but also could mean that the Cape’s sharks are more experienced hunters, and less likely to mistake a human for a seal.

As recently as a couple of years ago, people were being told that the great white sharks swimming off Cape beaches were in their teens, and that a 20-year-old was a senior citizen. Sexual maturity was thought to occur at between 4 and 10 years of age for males and 7 to 13 years for females.

But last January, shark researchers revealed that the great white shark lifespan rivaled that of humans. Lisa Natanson from the National Oceanic and Atmospheric Administration’s Apex Predator Program in Narragansett, Rhode Island, Li Ling Hamady and Simon Thorrold of the Woods Hole Oceanographic Institution, and state Division of Marine Fisheries shark scientist Greg Skomal used radiocarbon dating to age four female and four male great white sharks. They found the oldest female was 40 and the oldest male 73 years old, far beyond the 20 to 24 years determined by earlier studies.

The latest research by Natanson and Skomal, published this week in the online journal Marine and Freshwater Research, found that these great whites reached sexual maturity at a much later age, two to three times what had been thought of as adult. Skomal and Natanson examined vertebral samples from 77 great whites caught by commercial and recreational fishermen and research vessels between 1963 and 2010. By counting the growth rings in the vertebra, and using the radiocarbon data from the longevity study, they were able to reconstruct what is being called the first reliable growth curve for western Atlantic white sharks.

Read the full story at the Cape Cod Times

February 21, 2015 — However, there is uncertainty about the level of mercury concentration that can be contained within a member of the species, and whether there should be any concern about serving up the shelled reptile.

Montclair State University doctoral candidate Natalie Sherwood and Dr. Meiyin Wu, a biology and microbiology professor at the university and the New Jersey Department of Environmental Protection began investigating that matter back in 2013.

The project is still ongoing because the scientists have not been able to test enough turtles.

“Mercury contamination in human food poses a significant threat to human health globally,” Wu said. “The consumption of turtle meat is of special concern due to mercury's ability to bioaccumulate and biomagnify. Since turtles are long-lived predators, it allows for a higher degree of mercury bioaccumulation and biomagnification.”

The common snapping turtle is the largest turtle in the state, excluding sea turtles, according to the New Jersey Division of Fish and Wildlife, and can be found anywhere in the state.

The Department of Environmental Protection allows anyone with a valid fishing license or anyone entitled to fish without a license to take up to three snapping turtles per day from Jan. 1 through April 30 and from June 16 through Dec. 31.

Read the full story at the New Jersey Herald

February 17, 2015 — If you want to protect New England's most iconic fish and still allow fishermen to catch them, it’s critical to know when and where they reproduce. The trouble is, we don't.

It turns out cod and humans may not be as different as you'd think. Chris McGuire, marine programs director for The Nature Conservancy, says cod spawning (a.k.a. baby-making) behavior is a lot like a night club scene. During the day, things are pretty segregated; females are holed up in rocky outcrops, while males hang out around the edges. But after dark, things heat up. The females venture out and the "singles scene" ensues, as females check out their options and males grunt to attract a mate (cue the Barry White).

This is how cod spend the winter.

Unfortunately, sometimes, this love fest gets interrupted. Fishery scientists think that fishing boats can have the same effect as cops breaking up the party (Can you hear the needle scratching across the Barry White album?), and not just for one night. Once broken up, a spawning aggregation may not reform again that year.

That's a scenario that all involved parties – from fishermen to environmental groups, and everyone in between – would like to avoid. Fishermen, in particular, would like to do so without putting huge swaths of ocean off-limits to fishing for extended periods of time. But targeted closures require high-resolution information that has been largely non-existent.

A few years ago, a group of fishermen from Scituate, Massachusetts (the nearest port to some renowned spawning grounds), approached The Nature Conservancy with the idea of doing some research to shed some light on exactly when and where cod come to spawn. The cooperative research project that grew out of that now involves researchers at The Nature Conservancy, the Northeast Fisheries Science Center, Massachusetts' Division of Marine Fisheries, U. Mass. Dartmouth's School of Marine Science and Technology, and – last, but certainly not least – some of those self same fishermen.

Read the full story and listen to the audio from WCAI – Cape and Islands NPR Station

 

 

February17, 2015 — With a low price tag and mild flavor, tilapia has become a staple dinnertime fish for many Americans. Now it could have another use: helping to heal our wounds.

In the journal ACS Applied Materials & Interfaces, scientists have shown that a protein found in this fish can promote skin repair in rats without an immune reaction, suggesting possible future use for human patients.

Jiao Sun, Xiumei Mo and colleagues explain that applying collagen — a major structural protein in animals — to wounds can help encourage skin to heal faster. But when the protein dressing comes from mammals such as cows and pigs, it has the potential to transmit conditions such as foot-and-mouth disease. Searching for an alternative source of collagen, scientists recently turned to the ocean.

Read the full story from the American Chemical Society

 

February 2, 2015 — Long thought to be fish-eaters, the big-eyed animals have been observed taking on bigger prey in the North Sea.

It seemed a heart-warming sight: two seals apparently frolicking in the sea before slipping below the waves off the German island of Helgoland (map) in 2013.

Then an ominous sheet of red unfurled across the waves. When the pair resurfaced, the bigger seal was skinning and eating its companion. (Also see "Did Grey Seals Mutilate Two Harbour Porpoises?")

"We thought they were playing," says marine biologist Sebastian Fuhrmann of the environmental consulting firm IBL-Umweltplanung, whose photos of the killing of a young harbor seal will appear in the March 2015 issue of the Journal of Sea Research. "It looked really cute, but in just a few seconds, it was over."

The triumphant hunter of the harbor seal was, astonishingly, a gray seal. These soulful-eyed animals have long been thought to subsist on lowly creatures such as cod. But now the gray seal seems to be morphing into the most murderous killer of the southern North Sea.

New eyewitness accounts and forensic evidence have implicated the sumo wrestler-size marine mammals in the bloody mutilation and death of harbor seals and harbor porpoises across the region. Some of the latter apparently succumb after being ambushed and held underwater until they suffocate. (Watch a video of harbor seals hunting under the waves.)

Read the full story at National Geographic

February 12, 2015 — Water that is not too hot, not too cold, but just right. Like every other living organism, fish just want to be comfortable.

That's why, in the face of warming ocean water, they may be on the move. Dr. Malin Pinsky of Rutgers University, who studies the effects of climate change in fisheries, said many species are shifting to the north at a time when the climate has been warming.

"We're seeing a climate fingerprint in many of these shifts in species distribution," Dr. Pinsky said.

There's been unprecedented warming in the northeast, he added, with 2012 being the warmest year on record for ocean water in the region. "It was a real heat wave," he said.

Dr. Pinsky and Rutgers have just begun a joint research project with Stony Brook University, George Mason University and the University of North Carolina to understand whether a changing climate played a role in the shift and what the economic and regulatory impacts will be.

Sea Grant is funding the study and the Save the Summer Flounder Fishery Fund is part of the advisory board.

Read the full story from the Asbury Park Press

 

February 12, 2015 — Once abundant in the rivers of eastern North America, the Atlantic sturgeon has suffered a catastrophic crash in its populations. But new protections under the U.S. Endangered Species Act are giving reason for hope for one of the world’s oldest fish species.

Water from the iced-over Connecticut River numbed my hands as I cradled a hard, scaleless fish at the U.S. Geological Survey’s anadromous fish laboratory at Turners Falls, Massachusetts. Its back was dark brown, its belly cream. Five rows of bony plates ran the length of its thin body to the shark-like tail. Four barbels covered with taste buds dangled from its flat snout in front of the sucker mouth. At 20 inches it was a baby. Adults can

This fish was an Atlantic sturgeon — the largest, longest-lived creature that reproduces in North American rivers collected by the Atlantic. Its species is at least 70 million years senior to my own.

Yet my species threatens it with extinction.

While that threat is still very real, it was reduced on February 6, 2012, when the National Marine Fisheries Service (NMFS) protected five “distinct population segments” of Atlantic sturgeon under the Endangered Species Act. The Gulf of Maine segment was listed as threatened while the New York Bight, Chesapeake Bay, Carolina, and South Atlantic segments were listed as endangered.

This action has released a torrent of funding that is allowing researchers from Maine to Florida to identify and mitigate human-caused mortality.

Read the full story from Yale Environment 360

 

February 11, 2015 — Krill, menhaden, and salmon oils are finally being given a chance to be included in the draft of what would become the first-ever fish oil standard of the FAO/WHO’s Codex Alimentarius. The Codex Committee on Fats and Oils (CCFO) is holding a meeting in Malaysia this week to discuss whether to proceed with work on the fish oil draft standard. It’s been reported that CCFO has not only decided to continue working on the draft and advance it to the next stage, but that krill, menhaden, and salmon oils (both farmed and wild)—which previously were excluded—will now be included in the draft standard.

Concentrated fish oils will also remain in the draft standard, despite a scare earlier this week to remove it from the standard.

News on the CCFO Malaysia meeting came courtesy of the Global Organization for EPA and DHA Omega-3s (GOED; Salt Lake City) and the International Alliance of Dietary/Food Supplement Associations (IADSA).

Read the full story here

February 9, 2015 — New research suggests that to maintain Caribbean ecosystems, the waters require just the right amount of fish pee.

Researchers from the University of Washington and North Carolina State University figured out the ratios of chemicals and excretion the ecosystems need to survive. In a new study published in the journal Ecological Monographs, the scientists detail how a loss of fish biodiversity could impact larger ecosystems as a whole.

Read the full story from The Week

 

February 6, 2015 — A pair of Florida scientists have developed a device they say can genetically verify whether imported fish destined for dining tables are grouper or less expensive, potentially harmful Asian catfish often passed off for the popular firm-fleshed fillets.

By early summer, Tampa-based PureMolecular LLC hopes to begin selling the fist-sized machines for about $2,000 apiece, said John Paul, the company’s chief executive and a marine science professor at the University of South Florida.

Retailers trying to profit from mislabeling cheaper seafood as more expensive varieties have come under increasing fire from consumer and environmental activists and from seafood vendors who find it harder to charge the full price for properly labeled fish.

One group estimates that up to a third of the fish consumed in the United States could be mislabeled.

Read the full story from Reuters