ARCHIVE
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Increasing groundwater salinity changes water and crop management over long timescales
by Yiqing “Gracie” Yao and Jay Lund Salinity has often become a major limit for irrigated agriculture in semi-arid regions, from ancient Mesopotamia to parts of California today. A previous blog post showed that conjunctive use with more saline groundwater can differ fundamentally from freshwater aquifers. Higher salinity limits groundwater use for irrigation during dry…
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Looking for a new challenge? – Retrain as a Delta Smelt
Help restore one of California’s most endangered species while supporting California’s water supplies in a time of drought. The Federal government is beginning a program for the unemployed to retrain as much-needed Delta Smelt. Following a two-day course, candidates will learn to: Seek out turbid waters Spawn in sand at secret locations Surf the tides…
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Field courses help young people see the real world
by Andrew L. Rypel It was perhaps unsurprising I wound up a field ecologist. Raised in Wisconsin, I spent almost all my childhood free time roaming largely unchaperoned in nature, pre-internet. It was there that I developed a deep love for nature, water and fish that would stay with me my whole life. It was…
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That Time Warren Buffett Got Involved in California Water
by Andrew L. Rypel As if 2020, wasn’t completely strange enough, it wound up also being a time when Warren Buffett was plunged headlong into California water. Buffett of course is an American business tycoon – primarily an investor, and currently the 4th richest person on the planet. Although 90 years old, Buffett continues as…
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California’s New Drought
By Jay Lund, Andrew L. Rypel, and Josue Medellin-Azuara As March begins to drag on with little precipitation in the forecast and few weeks left in California’s traditional wet season, we are in another dry year. This is California’s second dry year in a row since the 2012-2016 drought. Statistically, California has the most drought…
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Managing Water and Crops with Groundwater Salinity – A growing menace
by Yiqing “Gracie” Yao and Jay Lund Salinity is an eventual threat to agriculture and groundwater sustainability in parts of California, and other irrigated parts of the world. Irrigation, lower groundwater levels, and natural conditions have dramatically increased groundwater salinity in parts of California over the last 150 years (Hansen et al. 2018). Nearly two…
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Celebrating Black Scientists in Fisheries & Biology
By Kim Luke, Christine Parisek, Rachelle Tallman, Marissa Levinson, Sarah Yarnell, Miranda Bell Tilcock, Andrew Rypel, and Jay Lund In honor of Black History Month, the Center for Watershed Sciences would like to highlight the contributions of Black scientists in our field. These prominent researchers have not only pushed the social and scientific boundaries of…
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Groundwater Salinization in California’s Tulare Lake Basin, the ABCSAL model
By Rich Pauloo and Graham Fogg Lower groundwater levels can prevent drainage of water and salts from a basin and increase aquifer salinity that eventually renders the groundwater unsuitable for use as drinking water or irrigation without expensive desalination. Pauloo et al. (2021) demonstrate this process for the Tulare Lake Basin (TLB) of California’s Central…
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Eat Prey Loon: lessons from juvenile loons in Wisconsin
by Brian A. Hoover, Andrew L. Rypel and Walter H. Piper Do you remember when you first moved from home, and were completely on your own in new surroundings? How did you decide where to live, or which restaurants to try for the first time? Did you try places randomly, or did you seek familiar…
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Can Japanese Smelt Replace Delta Smelt?
by Peter Moyle A question I get asked on occasion is: Why all this fuss about endangered delta smelt when there is another smelt that looks just the same that can takes its place? The smelt being referenced is the wakasagi (Hypomesus nipponensis), which is indeed similar to the delta smelt (Hypomesus transpacificus). In fact, both…
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February 1: Is California Still Heading for a Multi-Year Drought?
by Jay Lund, Peter Moyle, and Andrew Rypel This updates a post from December on the likelihood of California entering a second dry year. Normally, a second dry year brings drought operations for California’s overall water system operations. Today, it is even likelier that California is entering a multi-year drought. Precipitation conditions have improved somewhat…
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A Swiss Cheese Model for Fish Conservation in California
by Andrew L. Rypel, Peter B. Moyle, and Jay Lund We read with great interest Nicholas Chistakis’s piece outlining a “Swiss Cheese Model For Combating Covid-19” in the Wall Street Journal. Christakis presents a model for considering the individual steps needed to achieve a larger goal, and how each step should fit into a larger…
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Managing Groundwater Overdraft – Combining Crop and Water Decisions (without salinity)
by Yiqing “Gracie” Yao and Jay Lund California’s Central Valley produces much of the nation’s food, including about 40% of the country’s fruits and nuts and has the nation’s second most pumped aquifer system. Its drier southern portion, the San Joaquin Valley, has decreasing surface water supply reliability due to frequent and prolonged droughts, stricter…
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2021: Is this the year that wild delta smelt become extinct?
by Peter Moyle, Karrigan Börk, John Durand, T-C Hung, and Andrew L. Rypel 2020 was a bad year for delta smelt. No smelt were found in the standard fish sampling programs (fall midwater trawl, summer townet survey). Surveys designed specifically to catch smelt (Spring Kodiak Trawl, Enhanced Delta Smelt Monitoring Program) caught just two of…
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California’s Sacramento-San Joaquin Delta – a short history of big changes
by Jay Lund Deltas globally adjust with changes and fluctuations in external conditions, internal dynamics, and human management. This is a short history of big changes to California’s Sacramento-San Joaquin Delta (Delta) in the past and present, and its anticipated future. This history is important for understanding how many of the Delta’s problems have developed,…
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We Wish You A Silly Fishmas
by Kim Luke Night Before Fishmas “Twas the night before Fishmas, when all through the spaceNot a creature was stirring, not even a Dace;The fyke nets were hung by the boat dock with care,In hopes that St. Fish-olas soon would be there; The salmon eggs were nestled all snug in their redds;While visions of zooplankton…
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Picture this research – a photo blog from the Center for Watershed Sciences
by Scientists at CWS Holidays are a natural time of introspection on who we are, what we do, and why. Towards a bit of our own self-reflection, some researchers from UC Davis’ Center for Watershed Sciences (CWS) have each contributed a photo and short description of their work. We hope you enjoy reading about us…
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Making “productive” assessments of California’s ecosystems
by Andrew L. Rypel Conservation science and restoration ecology are challenging and interdisciplinary fields. Managing for ecological function necessitates focus on multiple scales of ecological organization while simultaneously integrating feedback loops with critical environmental drivers like temperature, flow and habitat change. This means scientists working on these issues can emerge from diverse areas of inquiry…
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Is California Heading for a Multi-Year Drought?
by Jay Lund Yes, California will have another multi-year drought. California has immense hydrologic variability, with more droughts and floods per average year than any other part of the country. California’s water users, managers, and regulators should always be prepared for droughts (and floods). Eventually, California will have a multi-year drought worse than any we…
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Functional Flows Can Improve Environmental Water Management in California
By Ted Grantham, Jeanette Howard, Belize Lane, Rob Lusardi, Sam Sandoval-Solis, Eric Stein, Sarah Yarnell and Julie Zimmerman Over the past three years, a team of scientists from universities, NGOs, and state agencies across California have been working to provide guidance on how to better manage river flows for freshwater ecosystems throughout the state. A…