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Oceans: Study finds that regional humpback whale populations should be classified as distinct subspecies

Northern and southern humpbacks rarely mingle

A humpback whale near Hawaii. Photo courtesy NOAA.

A humpback whale near Hawaii. Photo courtesy NOAA.

By Bob Berwyn

FRISCO — Humpback whales in the North Pacific, the North Atlantic and the Southern Ocean are much more genetically distinct than previously thought, and should be recognized as separate subspecies, according to biologists who carefully analyzed DNA from hundreds of whales around the world.

The findings could bolster conservation strategies for the whales, which were nearly hunted to extinction during the 20th century. While some humpback whale populations have made a strong recovery since the end of the whaling era, other isolated populations may need additional help to recover.

The findings could help federal biologists in the U.S. as they consider a proposal to designate North Pacific humpbacks as a single “distinct population segment” under the Endangered Species Act and illustrate the complexity studying and managing marine mammals on a global scale.

The bottom line, according to the paper published last week in the Proceedings of the Royal Society B last week,  is that humpback whales of the North Pacific, North Atlantic and Southern Hemisphere are on independent evolutionary trajectories. Continue reading

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Oceans: Does tagging aquatic animals affect behavior?

A female

A female loggerhead sea turtle equipped with two tags heads for the Gulf of Mexico from a beach in Dry Tortugas National Park. Photo courtesy Kristen Hart/USGS.

New study could help scientists come up with better tagging techniques

By Summit Voice

FRISCO — Well-meaning scientists have long been tagging all sorts of critters to try and get a better idea of where they go to feed, breed or just hang out. The data from such studies helps inform conservation planning, but it turns out the tags may have a negative impact on at least some aquatic animals.

In a new study, American and Canadian researchers quantified the energy cost to aquatic animals when they carry satellite tags, video cameras and other research instruments.

Studying fiberglass casts of sea turtles in a wind tunnel, the team found that, while most commercially available tags increased drag by less than five percent for large adult animals in the wild, these same devices increased drag by more than 100 percent on smaller or juvenile animals. Continue reading

Oceans showing strong response to global warming

‘An overwhelming response of species shifting where and when they live in an attempt to track a shifting climate’

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Marine environments are experiencing big changes due to global warming. bberwyn photo.

By Summit Voice

FRISCO — Some key ocean indicator species, including phytoplankton, zooplankton and bony fish, are moving towards the poles at the average rate of about 45 miles per decade in response to warming oceans — 10 times faster than the average movement of land species.

The findings are part of a new study, funded by the National Center for Ecological Analysis and Synthesis in California, providing more evidence that global warming will have substantial impacts on ocean ecosystems, including changes in the timing of breeding, feeding and migration of some species. Continue reading

New app for citizen scientists to measure phytoplankton

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A Secchi disk helps scientists measure the density of plankton. Photo courtesy University of Washington.

Researchers hope to develop a global plankton map to track global warming impacts

By Summit Voice

SUMMIT COUNTY — If you’re planning any ocean boating this year, you could help scientists track how global warming is affecting phytoplankton with new smartphone app. Some scientists fear that the minute organisms at the base of the marine food chain are dwindling, which would have significant consequences for all other marine organisms.

Some studies suggest that phytoplankton populations have already declined by 40 percent in some areas, but there haven’t been enough measurements to get a true global picture. That’s where the new Secchi app may help, according to Dr, Richard Kirby, a researcher at Plymouth University’s Marine Institute.

Secchi disks have long been used to measure phytoplankton density, simply by measuring the depth at which the disk disappears from view. The app enables mariners to report that measurement from wherever they are, and there’s even a Facebook page for seafarers who are participating in the project. Continue reading

Small fish make big splash in ocean carbon cycle

Fish poop.

Research team studies role of forage fish in sequestering carbon

By Summit Voice

SUMMIT COUNTY — A still-popular first-grade book described the heroic efforts of a small fish to make a big splash. Now, it turns out that Arty’s dream wasn’t all that farfetched.

According to a new study by scientists with Rutgers University and the Virginia Institute of Marine Science, forage fish like anchovies can play an important role as a biological pump in the cycle that moves carbon dioxide from the atmosphere into the depths of the ocean, where its sequestered without adding to heat-trapping woes of atmospheric greenhouse gases.

Dr. Grace Saba, of Rutgers University, and professor Deborah Steinberg, of the Virginia Institute of Marine Science, shifted their focus away from their long-term studies of copepods to looking at anchovies in the Santa Barbara Channel, off the California coast. Continue reading

Report: ‘Pitiful’ progress on global ocean conservation efforts

NOAA is reporting a resurgence of marine life in a protected around the Dry Tortugas, off Florida, including this area around Permit Reef. PHOTO COURTESY NOAA..

Marine resources still being degraded and exploited at an unsustainable rate

By Summit Voice

SUMMIT COUNTY — Listening to official government sources about the state of the world’s oceans is one thing, with a steady stream of “good” news often highlighting new marine reserves and the recovery of fisheries.

But on the whole, world leaders have made only “pitiful” progress in their promises to  protect global oceans from overfishing and other threats, according to the Zoological Society of London, which is hardly a hotbed of radical environmentalism. In fact, there has been little progress in meeting critical conservation goals in the past 20 years, the scientists wrote in a  study published June 15 in Science.

The researchers compared goals established at the World Summit on Sustainable Development in 2002. At the meeting, 192 countries agreed on targets for protecting vulnerable species and marine habitats and managing fishing sustainably in national waters.

Ten years on, none of these targets have been met, and in some cases the situation is worse than before, said the researchers with the zoological society, hardly known as a hotbed of radical environmentalism. Continue reading

Study: Catch of small schooling ocean fish should be halved

Demand for forage fish in recent decades has greatly increased for use as fish meal and fish oil to feed farmed fish, pigs, and chickens that people consume on a regular basis. Fish oil is also used in nutritional supplements for humans. PHOTO COURTESY LENFEST FORAGE FISH TASK FORCE.

Better management needed for ‘small but significant species’

By Summit Voice

SUMMIT COUNTY — Preserving healthy ocean ecosystems requires cutting back on harvests of herring, anchovy and other small schooling fish that are a vital link in ocean food webs, according to a new report from an international task force.

The so-called forage fish eat plankton and are, in turn, food for bigger fish, as well as penguins, whales, seals, puffins, and dolphins. They are primary food sources for many commercially and recreationally valuable fish found around North America, such as salmon, tuna, striped bass, and cod.

“Traditionally we have been managing fisheries for forage species in a manner that cannot sustain the food webs, or some of the industries, they support,” said Dr. Ellen K. Pikitch of the Institute for Ocean Conservation Science at Stony Brook University, who recently led a comprehensive worldwide analysis of the science and management of forage fish populations to date. Continue reading

Save the whales … with ‘cap and trade’

Three humpback whales surrounded by birds in NOAA's Stellwagen Bank National Marine Sanctuary. PHOTO COURTESY NOAA.

Economics, marine science professors team up to offer a market-based solution to whale conservation

By Summit Voice

SUMMIT COUNTY — A marine science professor and an economist from California say a market-based approach to whale conservation could help sustain populations of the cetaceans and also help whalers who make their living from killing the  marine mammals.

Anti-whaling groups like Greenpeace, Sea Shepherd, and the World Wildlife Fund spend at least $25 million per years on a variety of activities intended to end commercial whaling, yet every year, commercial whaling not only continues, but grows.

Instead of spending that money on anti-whaling activities, the groups could use the money on an open whale conservation market to purchase a share of the quotas, thus saving whales directly.

Under the current, largely unregulated system, the number of whales harvested annually has doubled since the early 1990s, to about two thousand per year and many populations of large whales have been severely depleted and continue to be threatened by commercial whaling. Continue reading

New surveys up estimates of coral reef biodiversity

Since the early days of marine exploration, biologists have been recording the stunning diversity of coral reefs.

Scientists use DNA barcodes to track ‘staggering diversity’ of world’s oceans

By Summit Voice

SUMMIT COUNTY — Cataloging species with DNA barcodes helped scientists with the Smithsonian National Museum of Natural History determine that the biodiversity in the world’s coral reefs has been seriously underestimated.

Coral reefs are some of the most endangered habitats on Earth. Given coral’s rapid decline and global range, DNA barcoding offered the scientists a quick and efficient method for their survey. Present estimates of species diversity in reefs are 600,000 to more than 9 million species worldwide.

“We cannot give a new estimate today, but we may be able to in a few years,”said Laetitia Plaisance, of the Smithsonian’s National Museum of Natural History and the Scripps Institution of Oceanography, and lead author of the survey. “Given the complexity and extent of the world’s coral reefs, the survey covered only a very limited depth and habitat range,” said Plaisance. “And yet we have so many more species than we ever expected.” Continue reading

Sea bass fisheries collapsing in Southern California

Over-fishing, changing ocean temps blamed for plummeting numbers as Scripps researchers unveil ‘illusion of plenty

Kelp bass numbers have dropped by 90 percent in the past 30 years. IMAGE COURTESY SCRIPPS INSTITUTION OF OCEANOGRAPHY.

By Summit Voice

SUMMIT COUNTY — Over-fishing and climate-driven changes in water temperature have combined to cause the collapse of two important recreational fisheries off the southern California coast in the past few decades.

Barred sand bass and kelp bass populations have declined by as much as 90 percent, but the drop has been masked because fishermen are still able to catch the fish in areas where they congregate to spawn, according to Scripps Institution of Oceanography postdoctoral researcher Brad Erisman and his colleagues, who examined the health of regional populations of the two species by combining information from fishing records and other data on regional fish populations.

Their findings were published in the most recent edition of the Canadian Journal of Fisheries and Aquatic Sciences. The researchers said the total amount, or biomass, of each bass species decreased 90 percent since 1980. Continue reading

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