By Andrew L. Rypel

“Way back in the days when the grass was still green and the pond was still wet and the clouds were still clean, and the song of the Swomee-Swans rang out in space…one morning, I came to this glorious place.

And I first saw the trees! The Truffula Trees! The bright-colored tufts of the Truffula Trees! Mile after mile in the fresh morning breeze.” ¹

I first saw California in 2010. At that point, I’d spent my entire life with a fairly specific vision of what California was supposed to look like. I suppose – surfing, palm trees, folks listening to Sublime on repeat. Yet when I finally got there, watching that warm orange orb ease artfully over the Pacific Ocean, I knew there was more. Staring back over my shoulder and up to the city, I marveled at the tangled and human-dominated landscape. But pulsing through it all, was this tiny incised urban stream. Its water ducked and spilled through the hills, urban areas, a vineyard, and finally emptied itself through a culvert box onto the beach. Here, it widened into a miniaturized estuary and began mixing with the ocean. Schools of bright silver fish danced below the surface, but further upstream, wading birds perched watchfully on posts to intercept any stray calorie fish bombs for dinner. All the while scads of humans, like me, strolled amongst the beach ecology pondering the meaning of life. California seemed a complicated, beautiful, and deeply interesting place. And I had this odd premonition that someday I might know much more about it.

It was summer 2016 when I interviewed and accepted a faculty job at UC Davis to become the inaugural Peter B. Moyle & California Trout Chair in cold water fish ecology. Suddenly, that odd premonition described above became prescient reality. We found a house in Davis, bit the bullet on real estate prices, and drove across the country to live, work and raise a family in California. I set about learning as much about California water and fish as I could. I read books, research papers, policy positions, news pieces, blogs – anything I could get my hands on. I followed conversations on Twitter (now X) to see more of the dynamics, people, and nuances of the issues. I met and talked with many knowledgeable people and communities during this time, perhaps even, some of you.

Things began to really hum at the right frequency though when I started teaching, sampling and studying the fishes. I am, after all, a fish ecologist. And the fish tell us a great much about the health of our watersheds. It didn’t take long for me to fall in love with the native fishes. Being a midwesterner, I was taken by the foreign and mysterious qualities of these overlooked but strikingly chic critters (Fig. 1). Species like the Sacramento Pikeminnow – a large predatory minnow with thick smooth lips; these fish were once top of the food chain in most Central Valley rivers. Tule Perch – a species resembling bluegill, my ‘gateway drug’ to fishing as a child. Tule Perch are viviparous (give live birth), can handle salty or fresh waters, and are quite the tricky customer to catch by hook and line. While wade fishing at dusk, I came within a palm’s reach of landing a large Eagle Lake Rainbow Trout hoisted from the Tule reeds lining Eagle Lake. Its deep burgundy cheeks glistened at me tauntingly, before it tossed my inline spinner from its mouth. “Not this time Andrew,” smirked the trout! On the marine side, I became a tad obsessed with the native rockfishes. Why are there 100 rockfish species in the Pacific Ocean, but only 7 in the Atlantic Ocean? Some rockfish species have exceptional lifespans (e.g., exceeding 200 years!), give birth to millions of live young, and the females can store sperm – cool.

And then of course…there are the salmon. Those impressive, large, and delicious creatures. It’s like they’re from some secret dimension, sent to help us be better and healthier people – more connected with nature and tapped into its mysterious rhythms. It is difficult to describe the joy that comes into the heart of a fish biologist when they first lay eyes on a wild salmon or a clear cold stream packed with spawning adults. For me, I can only describe it as some type of spiritual event.  

Ecologically, California is like a large island. Until only recently, it was exceedingly difficult for species to get in or out. There is, after all, an ocean on one side and massive mountains on the other. Thus, the native species which evolved have been here a long time and have high degrees of “endemism,” meaning they don’t occur elsewhere. This isn’t just true for fishes (Moyle 2002); California has high rates of endemism for plants, insects, herpetofauna and many other axes of biodiversity (Stebbins and Major 1965; Harrison 2013). In a nutshell, California is a special place that has produced many unique and rare species. Yet, oddly, there were many familiar fishes to me also; non-native species I grew up angling for obsessively in Wisconsin, where they are native. And I suppose in some ways, I felt a bit like one of these non-native Mississippian species myself. A guest in a foreign land, trying to find my place, but ultimately, a trespasser.

Having studied fish biology for many years, I had long been familiar with Peter Moyle’s work. If you don’t know, Peter Moyle is essentially a famous fish biologist, known worldwide. My personal opinion is that California may have taken him for granted. Most other US states never had access to an expert like Moyle, let alone for 50+ years. As of writing this, Moyle has an h-index of 96 according to Google Scholar (meaning he has 96 peer-reviewed papers that have been cited 96 or more times), and an i-10 index of 285 (meaning he has 285 papers that have been cited at least 10 times). He spent virtually his entire career studying the unique fish fauna of California and the many challenges associated with their conservation. Biologists across the globe look to Peter’s work for inspiration and wisdom, especially those struggling with declining native fish faunas. Peter trained an army of biologists across multiple generations; many of these people continue to populate the ranks of California agencies, universities, and other organizations. Few know that Peter’s father, John B. Moyle, was also a monumental figure in the fisheries field. John Moyle worked for the Minnesota Department of Natural Resources for many years, and is considered the father of the research arm of that agency. His work, even today, casts a long shadow on that region. Folks throughout the northlands know John Moyle’s work on lake classification (Moyle 1945; Moyle 1949), water quality standards to support wild rice (Moyle 1944; Moyle 1945; Moyle 1956), and other facets of midwestern fisheries management (e.g., Seaburg and Moyle 1964). I’ve even heard some refer to John Moyle as ‘Minnesota’s Aldo Leopold’. And as if that wasn’t enough, Peter’s mother, Evelyn Moyle was a trailblazing botanist with an MS in zoology (extremely rare at the time); her book with John on Northland Wildflowers is still the go-to reference. Why am I bringing all these things up? Well, because it was an incredible honor for me to hold a professorship bearing the Moyle name. Also that of California Trout – an organization whose praises I will openly sing to anyone. CalTrout really leans into the use of science, and they are major innovators in applied fish conservation. I will miss so many of my CalTrout colleagues, and the many supporters of this important organization. I tried to understand these things, took the job extremely seriously, and always knew that our work reflected directly on Peter and CalTrout. I still can’t believe I got the job.

California’s native fishes clearly require defending, and over the many years, Peter would often seem to appear magically out of the sky to remind people about the fishes. He really is very much like ‘The Lorax’ – the fictional character in the Theodor Seuss Geisel (Dr. Seuss) book by the same name. I mean, check out the mustache – Peter even looks like the Lorax (fig. 2)! In the face of excruciating pressure (such as in the federal listing of the Delta Smelt), Peter was always willing to ask the tough questions and speak plainly about the actual biological needs of the fishes and the role of science in solving these difficult problems. And I would be remiss to not also acknowledge the many original defenders of the fishes – the Indigenous peoples. I learned so much from listening to and collaborating with my Indigenous colleagues. As much as these fishes mean to me, they mean much more, and at even deeper levels to these peoples.

It is a bit uncanny the extent to which the plot of The Lorax mirrors the experience of California fishes. As mentioned often on this blog, at least 83% of our fishes face extinction if present trends continue (Moyle et al. 2011). These numbers are sadly increasing further, especially since the 1970s, a time frame over which the human population of the state effectively doubled (Fig. 3). Species are starting to go extinct. The trend is unrelenting and genuinely scary. Gobs of new fish species are added as candidates for listing by state and federal Endangered Species Acts every year; most all of them are eventually listed (Rypel and Moyle 2024). Few ever come off these lists. Wild Delta Smelt are wiped out (Moyle et al. 2021); none were caught again this year, as is now the standard. The Longfin Smelt is next. Chinook Salmon fishing is closed again this summer (that makes 3 years in a row). At best, the California salmon fishery will continue on, but probably in a series of boom (fishery open) and bust (fishery closed) cycles associated with drought and extremely engineered hatchery management activities (Rypel and Moyle 2023). Once upon a time, not long ago, nature delivered all the salmon needed with little intervention (Rypel 2023). How can the salmon fishers realistically continue under boom-and-bust business cycles like that? The reality is that most will not, and unless something changes fast, the industry will largely fold, and that stinks. At worst, salmon could just go away in California. Spring-run Chinook Salmon will probably be up-listed from ‘threatened’ to ‘endangered’ soon. Extinction from the wild is a real possibility for these fish. A petition to list Fall-run Chinook Salmon, once an unimaginable possibility, could realistically happen now. And sadly, such an attempt would probably have a strong case. The Clear Lake Hitch, another species of major significance to tribes, is tanking (Moyle and Taylor 2022). I could go on. Indeed, I’m growing more and more concerned that California is resembling the fictional city ‘Thneedville’ from The Lorax, and less the California we know and love. 

“I meant no harm. I most truly did not. But I had to grow bigger. So bigger I got. I biggered my factory. I  biggered my roads. I biggered my wagons. I biggered the loads of the Thneed’s I shipped out. I was shipping them forth to the South! To the East! To the West! To the North! I went right on biggering… selling more Thneed’s. And I biggered my money, which everyone needs.”

As my time in California took root, and as Peter increasingly tried to retire, I found myself similarly trying to vocalize the peril faced by our native fishes. Maybe this was subliminal, given my job title bore Peter’s name, or that I felt a certain amount of pressure to be like Peter. Or maybe it is just the kindred spirit I always felt to Peter and the fishes. Ultimately though, using my voice was necessary. Few people are in a position to unambiguously defend the fishes, and to call a spade a spade. I had a good number of projects that colleagues did not want to work on with me, often for fear of saying the wrong thing or making enemies. So, I never grew the mustache, but slowly, I began to appreciate a little of what it feels like to be a Lorax. It is so sad to watch such a unique and special fauna vanish before our eyes, on our watches, and certainly, by our own hands. And everyone has excuses.

I believe Peter and I share a realistic view concerning possible solutions to these problems. There are, after all, 40M people in California. We need food, water, agriculture, a productive economy, and a secure society. It’s for these reasons that most of my work focused on practical solutions to fish problems. Broadly, this kind of work represents an arm of environmental science known as ‘reconciliation ecology’. Examples of our work includes case studies like the salmon-rice project (Rypel et al. 2022; Tallman et al. 2024; Eadie et al. 2025), ecological recovery of Putah Creek (Rypel 2022; Jacinto et al. 2023; Hitt et al. 2025a, 2025b), and science to help manage spring-run Chinook Salmon in the San Joaquin River (Rypel et al. 2021; Hause et al. 2022; Holleman et al. 2022). Frank Lloyd Wright once described the need for architecture to be a ‘grace to the landscape instead of a disgrace’. That’s a similar flavor of what we were trying to do, but for ecosystems. The goal is not to go back in time to the way things were, but rather to optimize our footprint with nature. To protect and rehabilitate the best remaining spots. And then to blend our cities and farms into well-managed landscapes. To make it harder to tell where one starts and the other begins; and to use science to figure all this out. This is the way – the California way – the one that I sensed on that beach so long ago.

It was a tough decision to leave UC Davis and California. I won’t get into all the reasons here, but it was a combination of family reasons and career opportunity. Yes – I do have guilt about abandoning the fishes without a defender. However, there will be new ones. Peter’s army of former students are still in place and ready to stake their careers on the needs of these special animals and environments. And I am also so proud of all the students I helped train at UC Davis – every one of them. Many of these young professionals now also populate the ranks of the California fish and water spheres, or have otherwise continued on for further training.

What can you do?

The fishes need you too. By way of this blog, I ask all of you to also consider being voices for the fishes. To, in your own tiny or large way, also be a Lorax. To look soberly at the challenges our ecosystems face, and to speak openly and plainly on their needs. To support science and the scientists still working on these gnarly and wicked problems. I know from experience that The Center for Watershed Sciences (CWS) and UC Davis are populated to the gills with talented, young, and positive new thinkers. And the Center and its students always benefit from extra financial support, if you are just super busy and don’t know how to help 😉. Please don’t give into the pessimism that our problems are unsolvable or doomed because of some combination of politics, human nature, and entropy. Or that universities and science as an enterprise are rotten to the core – they are not. California’s problems are really hard, but they are solvable problems. This book by Stephen Pinker is an exposé devoted to the many ways that our world actually tends to get better over time, not worse. If you can, hold a native California fish, go find the salmon when they return to our rivers each year, watch over them, teach your children about them. They are a gift we can still give to the next generation – we just need to work our stuff out better. There is still time, just not much.

“SO… Catch! Calls the Once-ler. He lets something fall. It’s a Truffula Seed. It’s the last one of all! You’re in charge of the last of the Truffula Seeds. And Truffula Trees are what everyone needs. Plant a new Truffula. Treat it with care. Give it clean water. And feed it fresh air. Grow a forest. Protect it from axes that hack. Then the Lorax and all of his friends may come back.”

¹ Author’s note: peppered throughout this blog are direct quotes from The Lorax by Dr. Seuss. These quotes are identified in blue

About the Author

Andrew L. Rypel is an Adjunct Professor in the Department of Wildlife, Fish, & Conservation Biology at UC Davis and past Director of the Center for Watershed Sciences. He is currently Director of the School of Fisheries, Aquaculture, and Aquatic Sciences at Auburn University.

Further Reading

Eadie, J.M., D.S. Karp, and A.L. Rypel. 2025. A conservation footprint for multiple species of wildlife in California rice. https://californiawaterblog.com/2025/04/06/a-conservation-footprint-for-multiple-species-of-wildlife-in-california-rice/

Harrison, S. 2013. Plant and Animal Endemism in California. University of California Press.

Hause, C.L., G.P. Singer, R.A. Buchanan, D.E. Cocherell, N.A. Fangue, and A.L. Rypel. 2022. Survival of a threatened salmon is linked to spatial variability in river conditions. Canadian Journal of Fisheries and Aquatic Sciences 79: 2056-2071.

Hemphill, S., and J. Pastor. 2019. John Moyle: Minnesota’s Aldo Leopold. https://www.agatemag.com/2019/06/john-moyle-minnesotas-aldo-leopold/

Hitt, L.G., M. Willmes, G. Whitman, M.C. Miner, C.A. Jeffres, R. Johnson, D.E. Cocherell, N.A. Fangue, and A.L. Rypel. 2025. Early evidence for establishment of a Chinook salmon population in a restored watershed. Ecosphere 16: e70207.

Hitt, L.G., M. Willmes, M.C. Miner, M. Stevenson, C.A. Jeffres, R.A. Lusardi, N.A. Fangue, and A.L. Rypel. 2025. Build it, and they will come: Early evidence for establishment of Chinook salmon in Putah Creek, CA. https://californiawaterblog.com/2025/06/29/build-it-and-they-will-come-early-evidence-for-establishment-of-chinook-salmon-in-putah-creek-ca/

Holleman, R.C., N.A. Fangue, E.S. Gross, M.J. Thomas, and A.L. Rypel. 2022. Unlocking how Chinook salmon swim in California rivers. https://californiawaterblog.com/2022/07/10/unlocking-how-juvenile-chinook-salmon-swim-in-california-rivers/

Jacinto, E., N.A. Fangue, D.E. Cocherell, J.D. Kiernan, P.B. Moyle, and A.L. Rypel. 2023. Putah Creek’s rebirth: a model for other degraded streams? https://californiawaterblog.com/2023/07/08/putah-creeks-rebirth-a-model-for-reconciling-other-degraded-streams/

Moyle, J.B. 1944. Wild rice in Minnesota. The Journal of Wildlife Management 8: 177-184.

Moyle, J.B. 1945. Classification of lake waters upon the basis of hardness. Journal of the Minnesota Academy of Science 13: 8-12.

Moyle, J.B. Some chemical factors influencing the distribution of aquatic plants in Minnesota. The American Midland Naturalist 34: 402-420.

Moyle, J.B. 1949. Some indices of lake productivity. Transactions of the American Fisheries Society 76: 322-334.

Moyle, J.B. 1956. Relationships between the chemistry  of Minnesota surface waters and wildlife management. The Journal of Wildlife Management 20: 303-320.

Moyle, J.B., and E.W. Moyle. Northland Wildflowers: The Comprehensive Guide to the Minnesota Region. University of Minnesota Press.

Moyle, P.B. 2002. Inland Fishes of California. University of California Press

Moyle, P.B., J.V. Katz, and R.M. Quiñones. 2011. Rapid decline of California’s native inland fishes: a status assessment. Biological Conservation 144(10):2414-2423.

Moyle, P.B., K. Börk, J. Durand, T. Hung, A.L. Rypel. 2019. Futures for Delta Smelt, https://californiawaterblog.com/2019/12/15/futures-for-delta-smelt/

Moyle, P.B., K. Börk, J. Durand, T.C. Hung,  and A.L. Rypel. 2021. 2021: Is this the year that wild delta smelt become extinct? https://californiawaterblog.com/2021/01/10/2021-is-this-the-year-that-wild-delta-smelt-become-extinct/

Moyle, P.B. Saving Clear Lake’s endangered Chi. https://californiawaterblog.com/2022/07/17/saving-clear-lakes-endangered-chi/

Pinker, S. 2018. Enlightenment Now: The Case for Reason, Science Humanism, and Progress. Penguin Books.

Rabidoux, A., M. Stevenson, P.B. Moyle, M.C. Miner, L.G. Hitt, D.E. Cocherell, N.A. Fangue, and A.L. Rypel. 2022. The Putah Creek fish kill: learning from a local disaster. https://californiawaterblog.com/2022/04/24/the-putah-creek-fish-kill-learning-from-a-local-disaster/

Rypel, A.L. and P.B. Moyle. 2024. Watching native fishes vanish. https://californiawaterblog.com/2024/09/01/watching-native-fishes-vanish/

Rypel, A.L. 2023. Facing the dragon: California’s nasty ecological debts. https://californiawaterblog.com/2023/06/11/facing-the-dragon-californias-nasty-ecological-debts/

Rypel, A.L., G. Singer, and N.A. Fangue. 2021. Science of an underdog: the improbable comeback of spring-run Chinook salmon in the San Joaquin River https://californiawaterblog.com/2021/12/05/science-of-an-underdog-the-improbable-comeback-of-spring-run-chinook-salmon-in-the-san-joaquin-river/

Rypel, A.L., D.J. Alcott, P. Buttner, A. Wampler, J. Colby, P. Saffarinia. N. Fangue, and C.A. Jeffres. 2022. Rice and salmon, what a match! https://californiawaterblog.com/2022/02/13/rice-salmon-what-a-match/

Rypel, A.L. 2022. Being patient and persistent with nature. https://californiawaterblog.com/2022/10/16/being-patient-and-persistent-with-nature/

Rypel, A.L. 2022. Science happens. https://californiawaterblog.com/2022/09/11/science-happens/

Rypel, A.L. 2022. Nature has solutions…What are they? And why do they matter? https://californiawaterblog.com/2022/03/

Rypel, A.L., and P.B. Moyle. 2023. Hatcheries alone cannot save species and fisheries.  https://californiawaterblog.com/2023/04/30/hatcheries-alone-cannot-save-species-and-fisheries/

Seaburg, K.G., and J.B. Moyle. 1964. Feeding habits, digestive rates, and growth of some Minnesota warmwater fishes. Transactions of the American Fisheries Society 93: 269-285.

Stebbin, G.L., and J. Major. 1965. Endemism and speciation in the California flora. Ecological Monographs 35: 1-35.

Tallman, R.L., A.N. Wampler, G.P. Singer, C.A. Jeffres, D.E. Cocherell, J. Colby, N.A. Fangue, R.A. Lusardi, and A.L. Rypel, 2024. Does method of field preparation affect survival and growth of juvenile Chinook salmon in agricultural floodplains. River Research and Applications 41: 836-848.

CA’s commercial salmon season has been shut down — again- CalMatters