Fish Radio by Laine Welch
|January 11, 2019|
Eating seafood can save lives.
Premature birth is the leading cause of death for children under 5 years old worldwide, accounting for nearly one million deaths annually. Now there is proof that eating seafood or marine oils can significantly reduce that number.
The lifesaving ingredient? Omega 3 fatty acids.
The conclusion of a new Cochrane Review of 70 studies worldwide on nearly 20,000 pregnant women stated that omega’s from marine sources reduces early premature birth by a whopping 42 percent.
“The effect really has to be strong to see it in a Cochrane Review and I am very impressed that it has come out as significant as it has,” said Dr. Tom Brenna, a professor of pediatrics, chemistry and nutrition at Dell Medical School at the University of Texas.
Research on marine omega 3’s and pregnancy has been going on since at least 1992, Brenna said, who called the formal medical global collaboration and conclusions in the Cochran Review a ‘blunt instrument.’
“The number of studies and the number of women studied is large enough so that it is very difficult to imagine that future studies are going to affect these results. We really are looking at something that may well be the final word,” he said.
The results also included a 10 percent reduction in low birth weight babies of under 5.5 pounds.
Premature babies are at higher risk of a range of long-term conditions including developmental delay, learning difficulties and visual impairment. Brenna said marine-based omega 3 fatty acids also improves those problems.
“Many of us believe that omega 3s are important for continuing development of the neural system and of the eye,” he said. “The brain and the retina in the eye are really omega 3 organs. You can say that as calcium is to the bones, omega 3 is to the brain.”
A challenge now, Brenna said, is to translate the marine omega 3 findings on premature birth prevention and other positives into health policy and wider educational outreach.
“I think that we have a major effect here that ought to be heralded from the rooftops far and wide,” he said.
Fish smell snuffed - Fish scientists proved years ago that the tiniest traces of copper in water can affect a salmon’s sense of smell. New research shows that increasing levels of acidity in the oceans does the same thing.
Fish use their sense of smell to find food, avoid predators, find spawning areas, even to recognize one another. Losing it could threaten their very survival.
“In the environment that has some serious implications,” said Jason Sandahl whose research team at Oregon State University was one of the first to show how contaminants can disrupt the chemical balance of sea creatures, and that copper levels at just two parts per billion impaired small coho salmons’ sense of smell.
“If there are predators around and the fish are not able to response to these danger signals in the water, they would likely be the next snack for these larger predators in the water,” he added.
Oceans that are becoming more acidic have the same effect.
Research at the University of Washington and NOAA’s Northwest Fisheries Science Center is the first to show that high levels of carbon dioxide impair the sense of smell in salmon.
“We did this study because over the past 10 years there’s been a lot of research coming out of Australia on tropical reef fish and other places in the world looking at the effects of elevated CO2 in fish behavior,” researcher Chase Williams told KBBI in Homer.
Williams and his colleagues exposed young coho salmon in tanks for two weeks to different acidity levels from today and predicted at 50 and 100 years out. Ground up fish scales were added to indicate a predator attack, which usually prompts the salmon to hide or swim away. The juvenile cohos exposed to the higher acidity levels did not appear to even detect the smell.
The UW team also looked into where in the sensory-neural system the ability to smell erodes, and how it changes fish behavior.
“We found that the salmon are still likely still smelling the odors, so there are no changes in the way their nose is detecting them,” Williams said. “But we did pick up changes in the way that their brain was potentially processing those odor signals. So that’s what is likely driving the behavioral changes.”
The researchers said they hope their findings on such an iconic fish as Pacific salmon will alert more people to the consequences of carbon emissions being absorbed by our oceans.
Fish watch - Lots of winter fishing is going on and gearing up across Alaska.
The snow crab fishery gets going in earnest around this time of year in the Bering Sea.
Divers are still tapping away on the last bits of Southeast’s 1.7 million pound sea cucumber quota in just one open region. Divers also are still going down for more than 700,000 pounds of giant geoduck clams.
The winter king salmon season for Southeast trollers opened on October 1 and it’s been slow going. Fewer than 6,000 kings have been taken since the fishery opened on October 1; the five year average is closer to 16,000 fish. Based on new treaty agreements with Canada, Southeast’s winter troll catch rate will determine the takes for commercial and sport users this year and that will likely mean more cutbacks.
The state also has announced a full closure for king salmon in the Northern Cook Inlet region and Susitna River due to extremely poor returns.
Boats at Kodiak, Chignik and the South Alaska Peninsula are fishing for rockfish and a half million pound Tanner crab fishery opens at Kodiak on the 15th.
Turning to fish meetings – the state Board of Fisheries will meet from Jan. 15-19 in Anchorage to take up more than 60 proposals for Arctic/Yukon/Kuskokwim fish issues.
Stakeholders will learn later this month how much halibut will be available for this year’s fishery which begins in March. The International Pacific Halibut Commission will announce the catch numbers and other management updates when it meets January 28 through February 1 in Victoria, British Columbia.