Salmon

Researchers reveal the infectious impact of salmon farms on wild salmon

A new study published in the March 30th edition of the prestigious scientific journal Proceedings of the Royal Society B (a publication of the UK's national academy of science) shows that the transfer of parasitic sea lice from salmon farms to wild salmon populations is much larger and more extensive than previously believed. This quantitative analysis of parasite transfer is a scientific...

Alaskan puzzles, monitoring provide insight about North Pacific salmon runs

The University of Washington Alaska Salmon Program, the world's longest-running effort to monitor salmon and their ecosystems, has received nearly $2.4 million from the Gordon and Betty Moore Foundation to expand its sampling scope and sophistication. The Alaska-based program has applications for Pacific salmon all along the West Coast, providing insights into the fluctuating fortunes of s...

To sea or not to sea: When it comes to salmon sex, size sometimes doesn't matter

The ones that stay and the ones that stray are biological puzzles among Pacific salmon, of whom the vast majority ?but not all ?travel thousands of miles to sea and back to the streams where they hatched. There are chinook salmon populations in Idaho in which an occasional male stays put and matures when only 6 inches long ?that is, he's able to fertilize eggs at even that diminutive size,...

Divergent life history shapes gene expression in brains of salmon

Scientists working with salmon have found that gene expression in the brain can differ significantly among members of a species with different life histories. Their study indicates that roughly 15 percent of Atlantic salmon genes show differential expression in males who migrate from their freshwater birthplaces to mature in oceans versus those who do not leave the freshwater environment to matur...

Salmonella caught red-handed

Pathogens are becoming increasingly resistant to antibiotics, causing problems for therapy. Doctors need to have antibiotics available that work in new kinds of ways. The last few years of research have, however, found few such ways. One major difficulty for developers of antibiotics is choosing the proper point of attack against bacteria. There are hundreds of possible points of attack, accordin...

Escapee farmed salmon infiltrate fitter wild populations

There is growing concern about the threats that farmed Atlantic salmon escapees constitute to wild salmon populations. In new research published in the journal Molecular Ecology, researchers have found scientific e...

Leave it to salmon to leave no stone unturned

Like an armada of small rototillers, female salmon can industriously churn up entire stream beds from end to end, sometimes more than once, using just their tails. For decades ecologists have believed that salmon nest-digging triggered only local effects. But a University of Washington researcher writes in this month's BioScience journal that the silt, minerals and nutrients that are unlea...

Salmonella bacteria use RNA to assess and adjust magnesium levels

Researchers at Washington University School of Medicine in St. Louis have added a gene in the bacterium Salmonella to the short list of genes regulated by a new mechanism known as the riboswitch. The Salmonella riboswitch is the first to sense and respond to a metal ion, substantially expanding the types of molecules that riboswitches can detect to help cells assess and react to their env...

Salmon go veggie to save wild fish stocks

Salmon, like humans, require omega-3 fatty acids in their diet to function healthily. But as the fish farming industry expands, feeding salmon and other aquatic species with pellets containing fishmeal and oil derived from processing wild-caught marine fish is unsustainable in the long term. This is due to rising demands for these commodities for aquafeeds and other purposes in the face of finite...

Special chip provides better picture of salmon health

How do you tell if a fish is fit and well? This is a question which has troubled farmers and biologists for years, but now scientists may have come up with the answer - using DNA chips. By studying the genes of Atlantic salmon scientists from three UK universities are developing a DNA chip to monitor the health and performance of salmon, a tool which could both save the salmon industry thousands...

Salmon farms kill wild fish, study shows

New research confirms that sea lice from fish farms kill wild salmon. Up to 95 per cent of the wild juvenile salmon that migrate past fish farms die as a result of sea lice infestation from the farms. The results of the research have been published in the Proceedings of the National Academy of Sciences of The United States of America. "We know that fish farms raise sea lice levels, and we...

Salmonella survives better in stomach due to altered DNA

Since 1995 there has been a considerable increase in the number of infections with a specific type of Salmonella bacteria transmitted via food. This type, Salmonella serovar Typhimurium DT104, is resistant to at least five different antibiotics. Dutch researcher Armand Hermans found new genetic information in DNA of DT104 that might be involved in its survival and infection mechanism. This geneti...

Farmed salmon could become an invasive species in forest streams

Ever since the Norwegians expanded commercial farming of salmon in the 1960s, the industry has continued to rapidly grow worldwide. It has expanded to such a degree that prices for farmed salmon have plummeted and, there is concern that farmed fish may become the next invasive species. "Farmed fish escaping from marine net pens might become an invasive species in British Columbia, Washing...

New report: Explosive growth changes salmon industry

A new report, the first to take a comprehensive look at market competition between wild and farmed salmon, sheds new light on the contentious and complex issues surrounding farmed and wild salmon. The Great Salmon Run: Competition Between Wild and Farmed Salmon, released by TRAFFIC, the wildlife trade monitoring network of World Wildlife Fund and IUCN-the World Conservation Union identifi...