Background Articles

A parasitic isopod that scientists identified five years ago has all but decimated mud shrimp populations in coastal estuaries ranging from British Columbia to northern California - with the exception of a handful of locations in Oregon from Waldport to Tillamook.

Once one of the most common cetaceans in the Mediterranean Sea, the short-beaked common dolphin has declined throughout the region since the 1960s and in 2003 this population was classified as Endangered in the International Union for Conservation of Nature (IUCN) Red List. Here, we document the species’ precipitous decline in eastern Ionian Sea coastal waters across 13 yr. While 150 animals were present in the study area (1050 km2) in 1996, only 15 were observed in 2007. A 12 mo assessment of fishing effort and catch, together with circumstantial evidence, suggests that the decline was caused largely by prey depletion resulting from overfishing. We analyzed the impacts of various fishing gear and estimated the degree of resource overlap between common dolphins and local fisheries. The total biomass removed annually by 308 fishing boats in the study area averaged 3571 t, while that consumed by common dolphins was 17 t. Resource overlap between common dolphins and fisheries—expressed as an average Pianka index of 0.5—differed according to fishing gear, being higher for purse seiners (0.7) and beach seiners (0.4) and lower for bottom trawlers (0.1), trammel boats (0.2) and longliners (0.0). Only about 10 active purse seiners (4% of the total active fishing fleet) were responsible for 33% of the biomass removal, and likely had the greatest impact on prey of common dolphins. This study indicates a high risk of local disappearance of common dolphins in the very near future, unless fishery management measures are implemented immediately. Purse seining should be the main management target.

July 23, 2007 – Over the last five years, large, predatory Humboldt squid have moved north from equatorial waters and invaded the sea off Central California, where they may be decimating populations of Pacific hake, an important commercial fish.

Phytoplankton blooms are increasingly conspicuous along the world's coastlines, and the toxic effects of these blooms have become a major concern. Nutrient enrichment often causes phytoplankton blooms, which decrease water transparency, but little is known about the effects of such light regime changes on whole communities of the continental shelf. A series of simulations designed to evaluate the potential effects of shading by phytoplankton blooms on community organization were conducted using a balanced trophic model of the West Florida Shelf ecosystem and the Ecopath with Ecosim modeling approach. Many functional groups in the system were predicted to decline as benthic primary production was inhibited through shading by phytoplankton, especially when associated biogenic habitat was lost. Groups that obtain most of their energy from planktonic pathways increased when shading impact and associated structural habitat degradation were complemented by enhanced phytoplankton production. Groups predicted to decline as the result of shading by plankton blooms include seabirds, manatees, and a variety of demersal and benthic fishes and invertebrates. Some counterintuitive predictions of declines (mackerel, seabirds, and surface pelagics) resulted because these groups are somewhat dependent on benthic primary production. The overall effect of the simulated bloom-associated shading of benthic primary producers resembled a trophic cascade where the number of full cycles of biomass gains and losses was approximately equal to the number of trophic levels in the system (4.7). (C) 2003 Elsevier B.V. All rights reserved.

A team of researchers has found that black-browed albatrosses living on the Falkland Islands see rising divorce rates during times when the sea surface temperatures rise. They point out that hunger could lead to one or the other partner abandoning an egg or hatchling—events that could lead to one of the birds ditching the other.

"We never know for sure how they died, but it does seem like a lot of the evidence points to killer whale predation," Steve Ferguson, a research scientist with Fisheries and Oceans Canada, said Thursday.

The king crab harvest survey could indicate a second bleak year for crabbers in Washington, Oregon and Alaska as warm water affects the number of adult crabs.

This year, that industry came to a drastic halt. In October, the Alaska Department of Fish and Game closed both the the Bristol Bay Red King Crab and Bering Sea Snow Crab seasons. Kelty said he is expecting between the lost revenue from the past two years, intertwined with the suspended season, he is expecting both the crabbing industry along with sector businesses to lose close to a billion dollars.

Ricky Wright points to the bank of a creek to show one way his hometown has been affected by climate change. Many banks have eroded or collapsed, and now some favorite fishing spots that were once on solid ground are reachable only by boat.

More than 100 salmon trollers packed a Sitka meeting Wednesday night with sharp questions about the future of an iconic Southeast Alaska fishery, facing what could be an unprecedented full shutdown of this year’s chinook trolling season. State officials are scrambling to open the fishery after it was effectively closed by a federal judge — but damage has already been done.

As the climate warms and Arctic sea ice retreats and gets thinner, more light is getting through. “Since marine zooplankton respond to the available light, this is also changing their behaviour – especially how the tiny organisms rise and fall within the water column,” the AWI said in a news release on their website.

The Arctic Sounder - Serving the Northwest Arctic and the North Slope

North Pacific right whales, once numbering in the tens of thousands, swam throughout the Bering Sea until they were nearly wiped out by commercial hunters. Now the Eastern North Pacific right whale population is estimated to total about 30 individuals, and its habitat is believed to be concentrated in the southeastern corner of the Bering Sea.

Experts say a wasting disease epidemic has decimated about 95% of the sunflower sea star population from Alaska’s Aleutian Islands to Mexico’s Baja California peninsula. Without sea stars to keep them in check, sea urchins are causing a troubling decline in kelp forests that provide food and shelter.

“This is unprecedented in the United States for a mature, rationalized fishery to suffer a stock collapse, in part due to climate change,” the executive director of the Alaska Bering Sea Crabbers said.

Projections show rising sea levels could cause Canada’s beaches to retreat inland, in extreme cases by as much as half a kilometre. The best option may be to stand back and let it happen.

There were no bugs buzzing around the lights in the parking lot.

ICCT researcher Elise Georgeff has been investigating hydrogen as a potential replacement fuel. First, her team calculated how many ships could cross the Pacific Ocean using the existing hydrogen technology. "About 43% could be powered by using hydrogen fuel cells," Georgeff said.Unalaska and Adak islands in the Aleutians are in perfect locations to become pit stops in a trans-Pacific green corridor. Most of the international ships crossing from west to east follow the same path, and those two communities are right in the middle: about halfway through one of the world's busiest shipping lanes.

Alaska fishermen face challenges as the Bering Sea crab harvest resumes, with environmental and economic upheaval threatening the future of the industry. Scientists are questioning whether full recovery is possible in a warming world for these ailing crab populations that have supported some of the world’s most lucrative fisheries.

An executive order issued by President Biden extends the ban on Russian seafood imports to include products processed in other countries, closing a loophole from previous sanctions.