A biologist, economist, engineer, and geologist walk onto a bar…

California WaterBlog

Previous Posts

1–2 minutes

  • A Recorded Conversation with Dr. Peter B. Moyle

    With John Durand Dr. Peter Moyle was the main reason that I came to UC Davis fifteen years ago to study the confusing ecology of the San Francisco Estuary. Peter is a Distinguished Professor of Fish Biology, Emeritus, and one of the first people back in the 1970s to seriously study the diversity of California…

  • Science of an underdog: the improbable comeback of spring-run Chinook salmon in the San Joaquin River

    By Andrew L. Rypel, Gabriel Singer, and Nann A. Fangue “You can’t design a worse evolutionary strategy for the Anthropocene” There are many variants on this quote, and we’ve heard them often in reference to the status of native fishes in California and other freshwater organisms worldwide. Indeed, the statement rings true for Pacific salmon,…

  • How dry will 2022 be?

    by Jay Lund Last year, Northern California had very little precipitation in October and November, and we wondered if California was entering into a multi-year drought. Today, we know – last year became the 3rd driest year on record for northern California, in terms of precipitation. This water year, so far This year, Northern California…

  • Adjusting past hydrology for changes in climate

    by Jay Lund Segal’s Law: “Someone with one watch knows what time it is. Someone with two watches is never sure.”  Time is certain, but its estimation and measurement are uncertain, yet we are not in total ignorance. Many water management and regulation decisions require an understanding of current and future hydrology.  These include regulatory…

  • Which species will survive? Climate change enhances the vulnerability of California freshwater fishes to severe drought

    By Peter Moyle As I write this on an October weekend, rain is falling steadily in Davis and has been for most of the day. This is the first real rain we have had in over seven months. But it is not the end of the drought. Multiple storms are needed. The landscape is a…

  • Managing Water Stored for the Environment During Drought

    By Sarah Null, Jeffrey Mount, Brian Gray, Michael Dettinger, Kristen Dybala, Gokce Sencan, Anna Sturrock, Barton “Buzz” Thompson, Harrison “HB” Zeff Introduction Storing water in reservoirs is important for maintaining freshwater ecosystem health and protecting native species. Stored water also is essential for adapting to the changing climate, especially warming and drought intensification. Yet, reservoir…

  • Can one atmospheric river end California’s drought?

    By Andrew L. Rypel and Jay Lund Given the quantity and intensity of last week’s rain, an obvious question is: ‘Is the drought over?’ Alas, the answer is a resounding no. But, the data are interesting and worth thinking about in more detail. As of now, the 8 station index in the northern Sierra registers…

  • Fish eyes: the hidden diet journal

    by Miranda Bell-Tilcock It is strange to think of an eye as a diet journal, but a fish’s eye can tell much about what it has been eating at each point in its life. If we know what a fish has been eating and when, then we can figure out where a fish has been.…

  • Sometimes, studying the variation is the interesting thing

    By Andrew L. Rypel As scientists, we’re trained to key in on ‘response variables’. In my case, fisheries scientists often examine how fish physiology, populations, communities or whole ecosystems react to various environmental drivers or human alteration. Unfortunately, variation in data is too frequently looked upon as a nuisance, an after thought, or worse –…

  • Episode 2: “Unraveling the Knot” Water Movement in the Sacramento-San Joaquin Delta – Tidal Forces

    By William Fleenor, Amber Manfree, and Megan Nguyen Tides are the biggest driver of Delta flows, and in Episode 2 we look at their impacts in different locations under a variety of inflow conditions.  Tides have a twice-daily cycle in the region, with a range of about six feet at Martinez.  In the first part…

  • The Big California Drought Stories of 2021

    by Jay Lund Happy New Water Year!  October 1, 2021 is the beginning of the 2022 water year in California, the traditional beginning of California’s “wet season”, such as it will be. Although there are many fine and interesting stories from California’s current drought, so far, a few stories seem more important and worth summarizing…

  • Developing tools to model impaired streamflow in streams throughout California

    by Jeanette Howard, Kirk Klausmeyer, Laura Read, and Julie Zimmerman Droughts are extreme, but not necessarily extreme events — at least not in the way we humans usually experience events as discrete, episodic occurrences. Droughts are continuous and exhausting; they can come out of nowhere and take us on a rollercoaster of waiting for precipitation…

  • Risk Rating 2.0: A first look at FEMA’s new flood insurance system

    By Ryan Miller, Peter Hansen, and Nicholas Pinter Risk Rating 2.0 has been called the Federal Emergency Management Agency’s (FEMA)’s most significant reform in 50 years.  Roughly 77% of customers of the National Flood Insurance Program (NFIP) nationwide will see increases in their premiums, while the other ~23% will see reductions or no change.  FEMA…

  • Could California weather a mega-drought?

    By Jay Lund “Mega-drought” has become a frightful “thing” in public and media discussions.  In the past 1,200 years, California had two droughts lasting 120-200 years, “megadroughts” by any standard. Could the state’s water resources continue to supply enough water to drink, grow crops and provide habitat for fish with such an extreme, prolonged drought…

  • Lessons from Three Decades of Evolution of Cropland use in the Central Valley

    by José M. Rodríguez-Flores, Spencer A. Cole, Alexander Guzman, Josué Medellín-Azuara, Jay R. Lund, Daniel A. Sumner California’s Central Valley is the source of more than $30 billion of farm value. It produces more milk than any state outside California, and dominates national production of dozens of fruits, vegetables, tree nuts and rice. The valley…

  • Dammed hot: California’s regulated streams fail cold-water ecosystems

    by Ann Willis, Ryan Peek, and Andrew L. Rypel Given the current drought, it’s no surprise that California’s dams are struggling to provide cool water habitats to support native freshwater ecosystems. But what if they were never able to support them under any conditions? New research shows how current stream management fails to provide the…

  • 2021 Drought in California – in one page

    by Jay Lund Droughts and this drought in California California has more hydrologic variability than any state in the US, meaning that we have more drought and flood years per average year than any other state.  This is a problem, but has also meant that we have designed for droughts, which are always testing us.…

  • Living with non-native fishes in California requires using the right words

    by Peter Moyle Everywhere you go in California, people live in landscapes where non-native species are conspicuous:  European grasses turning the hills golden, earthworms tilling our garden soil, exotic trees providing shade, bullfrogs jumping into backyard ponds, starlings making tight maneuvers overhead. In this blog, I want to describe the language of our relationships with…

  • The California Water Model: Resilience through Failure

    by Nicholas Pinter, Jay Lund, Peter Moyle This is a slightly-edited re-posting from May 5, 2019. A review of 170 years of water-related successes in California suggests that most successes can be traced directly to past mistakes.  California’s highly variable climate has made it a crucible for innovations in water technology and policy.  Similar water…

  • Experimental Habitats for Hatchery Delta Smelt

    by Peter Moyle The Delta smelt is either extinct in the wild or close to it; in the past year only a handful have been caught, with great effort. In contrast, the UC Davis Fish Conservation and Culture Laboratory (FCCL) has considerable success spawning and rearing the smelt in captivity. This coming winter, the FCCL…

All Archives