SCIENCE FRYDAY: Nerd out on salmonid science with RETU

Nearly every Friday, Redwood Empire Trout Unlimited shares an interesting bit of news related to salmonid & conservation science. Check them out below, and follow the latest posts on our Facebook Feed @redwoodempire-tu.

January 2019

SCIENCE FRYDAY: Salmon don’t like the smell of watercress, or that of shrimp. Why is this important to biologists? (1/25/2019)
SCIENCE FRYDAY: Pacific salmon abundances are at historically high levels, with pink and chum salmon doing well. But no one knows why. An international team of scientists hopes shed some light on this. (1/11/2019)
SCIENCE FRYDAY: Using slime eDNA to count salmon shows promise as a cost-effective monitoring method, potentially allowing many more streams to be tracked. (1/4/2019)

December 2018

SCIENCE FRYDAY: A McKinleyville man recently created an equation to better target tricky parasites linked to Klamath River salmon deaths. (12/21/2018)
SCIENCE FRYDAY: What are the "Family Values" of winter steelhead? (12/14/2018)
SCIENCE FRYDAY: Why are salmon shrinking? (12/07/2018)

November 2018

SCIENCE FRYDAY: The 4th National Climate Assessment is out, and it is dire. The report warns that the "San Francisco Bay and San Joaquin/Sacramento River Delta are particularly vulnerable to sea level rise and changes in salinity, temperature, and runoff; endangering one of the ecological 'jewels' of the West Coast, growing development, and crucial water infrastructure." (11/30/2018)
SCIENCE FRYDAY: Systematic conservation planning tools like Zonation and MARXAN can help planners create networks of protected areas or prioritize restoration funding. These tools help conservation groups get the best “bang for the buck” with limited conservation or restoration resources. So, what did the study find in the Redwood Empire? The authors note that the Russian River is an area that has been degraded and also is vulnerable to future impacts, meaning the Russian needs mitigation and restoration. However, the study also notes that the North Coast streams are in relatively good shape and the focus should be on increased protections and monitoring. How does your favorite river rank? (11/23/2018)
SCIENCE FRYDAY. International battle of the fry! Researchers found that rainbow trout fry from California were able to tolerate higher water temperatures and low-oxygen environments better than fry from Canada. (11/16/2018)
SCIENCE FRYDAY: Are strong steelhead runs linked to pink salmon abundance? (11/09/2018)
SCIENCE FRYDAY: Land-locked Atlantic salmon retain their ability to use the earth's magnetic fields to navigate, raising concerns that escaped farm raised fish will impact native populations. (11/02/2018)

October 2018

SCIENCE FRYDAY: What opportunities exist for science collaboration and funding in the delta? This report examines delta policymaking and scientific progress, and gives 7 recommendations. (10/26/2018)
SCIENCE FRYDAY: New citizen scientist tool unveiled that encourages volunteers map salmon deaths, helping to track mortality from toxic chemicals. (10/19/2018)
SCIENCE FRYDAY: Samples of chinook salmon revealed everything from cocaine to amphetamines and nicotine byproducts in fish tissue. (10/12/2018)
SCIENCE FRYDAY: The nearly 5-degree Fahrenheit temperature increase forecasted could reduce the trout habitat by half in this century, sending their numbers into a tailspin. (10/05/2018)

September 2018

SCIENCE FRYDAY: How driving results in salmon roadkill. (09/28/2018)
SCIENCE FRYDAY: Researchers are concerned that salmon spawning in the Central Valley are getting younger. Younger salmon have lower reproductive success and contribute fewer individuals to the next generation than older salmon. (09/21/2018)
SCIENCE FRYDAY: Salmon leap to overcome obstacles, to eat and... to remove lice? (09/14/2018)
SCIENCE FRYDAY: How do steelhead trout manage to survive in the lagoons at the mouth of rivers & streams before the sandbar breaks? From Wild Steelheaders United (09/07/2018)

August 2018

SCIENCE FRYDAY: The number of Coho returning to the Russian River Watershed in 2017/18 is high, according to a new report from California Sea Grant. This could be an indication of good ocean conditions for the 2016 cohort and a promising return of adults in 2018/19. (08/31/2018)
SCIENCE FRYDAY: How to be a citizen scientist while fishing -using iAngler, iFish Forever & more tools. (08/24/2018)
SCIENCE FRYDAY: Biologists from California Sea Grant "crawl, swim, and slither" up the tributaries of rivers in scuba gear, counting the number and species of salmon they spy to measure the health of the population. (08/17/2018)
SCIENCE FRYDAY: Our understanding of how wildfires affect hydrology in Northern California is limited. A new study hopes to change this. (08/10/2018)
SCIENCE FRYDAY: Powell’s map of the “Arid Region of the United States,” presented to the U.S. Senate in 1890, offered a new vision of the American West sectioned off by watersheds rather than on traditional political boundaries. (08/03/2018)

July 2018

SCIENCE FRYDAY: More on the new study that shows just little bit of water makes a critical difference to salmonids. Listen to RETU's John Green of Gold Ridge Resource Conservation District and Gregg Horten of Sonoma Water explain it in this short video. (07/27/2018)
SCIENCE FRYDAY: Livestock grazing increasing stream temperatures in critical salmon habitats. New study quantified the effects of land management activities on stream temperatures across the Pacific Northwest. h/t Salmon Network ( (07/27/2018)
SCIENCE FRYDAY: Sometimes evolution is very fast. These saltwater trout adapted completely to fresh water in about 100 years. (07/20/2018)
SCIENCE FRYDAY: 40 years of salmon population data from across the West Coast shows that older, larger Chinook salmon are becoming increasingly rare across most of the species’ North American distribution. (07/13/2018)
SCIENCE FRYDAY: Rivers cover 44% more of the earth than previously thought. The finding has implications for the study of climate change, because rivers exchange greenhouse gasses with the atmosphere, especially when people pollute their waters. (07/06/2018)

June 2018

SCIENCE FRYDAY: Are there benefits to actively conserving nonnative "guest" species such as introduced brown and rainbow trout, even though this can result in significant conflicts for aquatic ecosystem management? (06/29/2018)
SCIENCE FRYDAY: The results of the 2017 fishing season in California reveal both an underwhelming harvest and shockingly low numbers of fish returning to rivers in the Central Valley, likely reflecting both the impacts of drought and the challenges of accurately forecasting salmon abundance. (06/15/2018)
SCIENCE FRYDAY: Researchers have identified a single gene that appears to control whether Steelhead trout and Chinook salmon migrate upriver before or after reaching sexual maturity. (06/08/2018)
SCIENCE FRYDAY: An estimated 50 percent of the 191,000 acres of meadow in the Sierra are degraded by human impacts, negatively affecting fish habitat across the watersheds. The Meadow Condition Scorecard is a rapid assessment method to quickly assess overall meadow condition and help identify meadows in need of restoration. (06/01/2018)

May 2018

SCIENCE FRYDAY: Over the past five years the estimated number of adult Chinook Salmon spawners has increased from eight in 2013 to over 500 in each of the past three years. Kudos to the terrific restoration work from so many including Trout Unlimited John Muir Chapter, Putah Creek Council, Putah Creek Trout, Sonoma County Water Agency and many more. (05/25/2018)
SCIENCE FRYDAY: New approaches to water storage have emerged as the dam era has waned. Adoption of the new methods has caused California’s water storage to increase dramatically, along with big cost savings and less destruction of habitat. (05/18/2018)
SCIENCE FRYDAY: Flood waters inundate Sacramento in 1862. These epic floods - with 40 days of nearly nonstop rain - could return with increasing frequency according to this study led by Daniel Swain at UCLA. (05/11/2018)
SCIENCE FRYDAY: Research from FISHBIO shows surprising recovery for trout in the Stanislaus - nearly double the 2015/2016 estimates. Trout were also observed in the most downstream reach (between Orange Blossom Bridge and Oakdale) in 2017, where they had been absent in 2016. These results suggest stream conditions have returned back to within tolerable limits, bringing some hope for trout and good news for anglers. (05/04/2018)

April 2018

SCIENCE FRYDAY: Researchers learn that single spawning fish are more successful than first-time repeat spawners their age, pointing to a tradeoff between mortality and reproduction. Single spawners die after reproduction, so they give everything they have to their one batch of eggs. Repeat spawning fish, on the other hand, save some of their energy for later. (04/27/2018)