About these ads

Study tracks big drop in Pacific walrus numbers

PHOTO: U.S. GEOLOGICAL SURVEY Melting Arctic sea ice is forcing walrus colonies into a shore-bound existence to which they aren't adapted. Scientists say they've documented several cases of young calves being trampled in stampedes.

 Melting Arctic sea ice is forcing walrus colonies into a shore-bound existence to which they aren’t adapted. Photo courtesy USGS.

Melting sea ice likely a factor in population decline

Staff Report

FRISCO — With a 2017 endangered species listing deadline looming, federal researchers are trying to pinpoint Pacific walrus population numbers. In the newest study, the U.S. Geological Survey said the population dropped by about half between 1981 and 1999, but scientists aren’t sure if the numbers have stabilized since then.

in 2011, the U.S. Fish and Wildlife Service acknowledged that the species was under pressure from sea ice loss and over-harvesting, but didn’t formally add the Pacific walrus to the endangered species list. A federal court said the agency must make a final determination by 2017. Continue reading

About these ads

New mapping traces origins of ocean debris

Ocean boundaries redefined

Patches of plastic debris accumulate where they are concentrated by ocean currents.

Patches of plastic debris accumulate where they are concentrated by ocean currents.

Staff Report

FRISCO — Shredded bits of plastic now outweigh plankton in parts of the Pacific Ocean, posing a growing risk to to fish, turtles and birds that eat the trash. Efforts to limit the debris haven’t progressed much in the past few years, but new modeling of ocean currents may help researchers determine exactly where the waste is coming from.

“In some cases, you can have a country far away from a garbage patch that’s unexpectedly contributing directly to the patch,” said Gary Froyland, a mathematician at Australia’s University of New South Wales.

For example, the ocean debris from Madagascar and Mozambique would most likely flow into the south Atlantic, even though the two countries’ coastlines border the Indian Ocean. Continue reading

Environment: It pays to clean up beaches

Study shows costs of coastal litter

asdf

Beach-goers tend to avoid dirty beaches, even it means driving farther and spending more money to find a clean spot. bberwyn photo.

STAFF REPORT

FRISCO —Littered beaches are a costly economic liability in California, as beach-goers tend to avoid local beaches if they’re dirty. The economic study, funded by NOAA’s Marine Debris Program, showed that having no marine debris on the beach and good water quality were the two most important factors in deciding which beach to go to.

Given the enormous popularity of beach recreation throughout the United States, the magnitude of recreational economic losses associated with marine debris has the potential to be substantial.  Continue reading

Oceans: Pacific bluefin tuna on the brink as feds seek input on new fishing regulations

d

Even the imminent decimation of tuna populations hasn’t stopped sport fishermen from harvesting the desirable fish in the Gulf of Mexico and elsewhere. bberwyn photo.

Not enough adults left to replenish populations

Staff Report

Donate to the Rocky Mountain Climate Ranger project

mtnYour contribution to this independent journalism project will be matched dollar for dollar by Beacon. Click to learn more and make a donation.

FRISCO — Pacific bluefin tuna won’t last long at any sustainable level without immediate and drastic intervention by fisheries managers, according to ocean advocates who are urging the federal government to adopt strict limits on bluefin tuna catch.

Overall, many tuna populations are on the brink of collapse. Five of eight tuna species have been assigned threatened or near-threatened status on the international Red List maintained by the International Union for the Conservation of Nature.

In the Gulf of Mexico, for example, the Deepwater Horizon oil disaster spewed millions of gallons of oil into the species’ prime breeding grounds, and a 2010 report by the International Consortium of Investigative Journalists showed how illegal fishing and inadequate enforcement are decimating tuna stocks all over the world. Continue reading

4 years after Deepwater Horizon oil disaster, dispersant still found lingering in the environment

Study looks at concentrations of oil and dispersant in ‘sand patties’ found along the Gulf Coast

32 beaches were sampled, with contamination found at 26 sites. MAP COURTESY JAMES "RIP" KIRBY, UNIVERSITY OF SOUTH FLORIDA.

In 2012, University of South Florida scientists found oil remnants all along the Gulf Coast, often at levels that pose a potential risk to human health. MAP COURTESY JAMES “RIP” KIRBY, UNIVERSITY OF SOUTH FLORIDA.

New research in Florida shows

The mess from BP’s Deepwater Horizon oil disaster is still not completely cleaned up.

Read more Summit Voice stories about dispersants and the aftermath of the Deepwater Horizon spill here.

By Summit Voice

FRISCO — Fossil fuel companies involved in offshore oil drilling may have to rethink their emergency response plans for oil spills after a new study showed that dispersant used to prevent large slicks persists in the environment much longer than previously thought.

Scientists at Haverford College and Woods Hole Oceanographic Institution (WHOI) has found that the dispersant compound DOSS, which decreases the size of oil droplets and hampers the formation of large oil slicks, remains associated with oil and can persist in the environment for up to four years.

The EPA approved the use of massive quantities of dispersant after the 2010 Deepwater Horizon oil disaster in hopes of preventing oil from fouling beaches, reasoning that the chemicals degrade rapidly. The Deepwater oil spill was the largest ever, releasing at least 210 million gallons of oil. BP applied almost 2 million gallons of dispersant, much of it deep beneath the surface.

But it’s far from clear that the use of dispersant is an overall environmental benefit. Ongoing studies have shown that the mixture of dispersant and oil is far more toxic to many marine organisms than either substance on its own. For example, a study by scientists with the Georgia Institute of Technology and Universidad Autonoma de Aguascalientes, Mexico showed that the oil-dispersant mix was up to 52 times more toxic to tiny rotifers, microscopic grazers at the base of the Gulf’s food chain. Continue reading

Study: English Channel all fished out

Scientists call for network of protected areas

yj

The English Channel. Photo courtesy NASA.

Staff Report

FRISCO — The English Channel is all but fished out, leaving fishermen scraping the bottom of the barrel in their quest for a commercial haul.

Sharks, rays, cod, haddock and many other species at the head of the food chain are at historic lows with many removed from the area completely, according to UK marine biologists, who analyzed catches over the past 90 years and found significant evidence of the practice of fishing down the food web.

“It is clear from our analyses that fishing pressure has caused significant changes to food webs of the English Channel over the past 90 years,” said Plymouth University Professor Jason Hall Spencer, with the School of Marine Science and Engineering, and the Marine Institute.

The report, published in the PLOS ONE journal, used catch statistics from the International Council for the Exploration of the Seas to establish a ‘mean trophic level’ for catches – an average for how far up the food chain the fish are located. Continue reading

Oceans: Mediterranean fish in steady decline

gfhj

Albanian fishermen tend nets in Saranda. bberwyn photo.

Unregulated coastal fisheries, juvenile catch threaten sustainability

Staff Report

FRISCO — Stocks of commercially valuable fish in the Mediterranean Sea are disappearing steadily because of a lack of good planning and management, as well as inadequate enforcement of existing regulations. Without action, some species are likely to disappear, scientists warned last week in a report showing that fisheries resources in the Mediterranean have deteriorated in the past 20 years.

The report evaluated nine fish species and called for stringent monitoring of Mediterranean fishing activities, better enforcement of fisheries regulations, and advanced management plans in Mediterranean waters. The findings were published July 10 in the Cell Press journal Current Biology.
Continue reading

Follow

Get every new post delivered to your Inbox.

Join 7,491 other followers