For most modern-day fly fishers, the concept of catch-and-release is as familiar as the idea of hooking a fish on a fly rod. Back in the 1970s, though, it was an odd proposition. But a young fish biologist named Peter Moyle pushed the practice to balance conservation and recreation on a newly conserved stretch of California’s McCloud River. Needless to say, the idea stuck. The McCloud today is one of California’s most hallowed fly-fishing streams, and its best stretch of fly water is open to anglers thanks to the practical solution Moyle advocated. His solution also helped usher in a way of thinking about and handling native fish that today is second nature for nearly every fly angler out there.
Since those early days, Moyle has become California’s preeminent expert on coldwater fish. He is Distinguished Professor Emeritus in the Department of Wildlife, Fish, and Conservation Biology at the University of California at Davis, and his forward-thinking, hands-on approach to science and conservation has touched nearly every stream in California.
For his immense contribution to our knowledge of rivers and fish, Moyle is nothing short of legendary—and not just in the world of academia. From fly shops to nonprofit boardrooms, if you mention his name you’ll get the same reverent response.
Part of what you hear about is Moyle’s conservation work: returning water to the San Joaquin River; bringing a mined-to-death salmon stream back to life in Davis; or using the Endangered Species Act to protect California coho. You’ll also hear about his ability to bring the most complex ideas and scientific concepts down to earth where people can wrap their brains around them, connect to them, and embrace them. And, of course, you always hear about what an unassuming, optimistic, quick-to-smile, thoughtful guy he is.
So it’s hardly surprising that Peter Moyle won Fly Fisherman’s 2020 Conservationist of the Year Award. Western Rivers Conservancy on February 5 will receive a $10,000 grant from Simms Fishing Products in his name.
Moyle, now 77, moved to California from Minnesota in 1969, when the state had half the population it does today, and at a time when little was known about its native fish.
He began teaching at the University of California at Davis in 1972 and has since written 11 books and published more than 250 peer-reviewed papers on freshwater and anadromous fishes, a jaw-dropping body of work. Two of Moyle’s books, Inland Fishes of California and Fishes: An Introduction to Ichthyology are required reading for every budding biologist, the latter is a standard text in classrooms worldwide.
In 1998, Moyle and the geologist Jeffrey Mount cofounded the Center for Watershed Sciences, now California’s leading academic institute in water management. The center takes a truly interdisciplinary approach to understanding rivers and river conservation. It has greatly improved our understanding of rivers and how to keep them healthy.
“Jeff and I found we enjoyed working together on river problems, and then found compatible students, faculty, and researchers to work with us,” says Moyle. “Rafting trips down wild rivers in the Western U.S., British Columbia, and Alaska also encouraged people to keep working with us and the center.”
Although Moyle is an academic, he has never confined his work to the offices and bookshelves of the university. Instead, he has applied his work again and again to creatively solving problems facing California’s streams. And, when necessary, he has taken his findings into the courtroom to defend and advocate for rivers and fish.
“Peter is an academic who has always kept his eye on the prize of conservation and impact,” said Jacob Katz, a former grad student of Moyle’s and now a biologist for CalTrout. “He saw things from a fish-eye view that he never let go of. To have that perspective, grounded in solid science and not be fearful of advocating for what he knew was right, at the center of one of the most politicized resources anywhere—California water—is unique. He would go into the center of the fray in a courtroom and stand up for the truth.”
One of the cases most associated with Moyle is Putah Creek, a tributary of the Sacramento River that flows through the southern edge of the UC Davis campus. The creek was once a healthy salmon stream, and its upper reaches are still prime trout water. When Moyle landed in Davis in the early 1970s, the lower reach of Putah Creek was basically a waterless gravel pit, mined by the university for its rock and drained of its water by Solano County. There were no salmon.
It was Moyle’s decades-long study of the stream that allowed him and an organization called the Putah Creek Council to successfully sue the county, establishing better flows for fish below Solano Dam. Thanks to Moyle, a strategic flow regime to attract fish was finally established in 2000, and almost immediately the creek responded. Nonnative species dropped off, and native species began to increase. Then, in 2013, his hard work paid off. Chinook salmon showed up for the first time in decades. At first it was just a few, and then it began increasing year after year. Today, the university records 20,000 to 30,000 outmigrating smolts every year, and in 2017, a record 1,700 adult salmon returned to the river.
“Putah Creek was the puddle in his backyard and ignored by everyone else,” said Katz. “He wanted to reprogram the flows so the native fish could recognize the creek and flourish, instead of the invasive ones. It was truly revolutionary.”
Moyle’s work on that small, overlooked stream set the stage for restoration of the San Joaquin River, which, in 2019, saw its first return of salmon in half a century. And Putah Creek has served as a model for functional flows and river restoration across the country.
Moyle has also worked directly with numerous other conservation organizations throughout his career. CalTrout, Western Rivers Conservancy, American Fisheries Society, Water Audit California, the Public Policy Institute of California, The Nature Conservancy, Earth Justice, and the National Heritage Institute all owe elements of their successes to Moyle and the volunteer time he has given.
Moyle has served as a volunteer board member of Western Rivers Conservancy for seven years. His participation has helped guide its efforts and enhance its knowledge of which streams matter most.
“Peter is our sage,” said Sue Doroff, president of Western Rivers Conservancy. “His depth of knowledge has shaped how we look at river conservation on the one hand, and on the other, has fueled the enthusiasm and passion we have for so many of our projects.”
The Blue Creek Salmon Sanctuary on the Klamath River, which Western Rivers Conservancy recently created in partnership with California’s Yurok Tribe, is a perfect example. The Klamath was once the third largest producer of salmon on the West Coast and is now, perhaps more than any river in the state, ground zero for West Coast salmon recovery, the focus of what is poised to be the largest dam removal project in the country. If and when it happens, it will almost certainly be a game changer for fish.
As the decision to remove the Klamath’s dams was shaking out, and in the shadow of a basin-wide struggle over water rights, Western Rivers Conservancy was busy buying 47,000 acres of land from a timber company to create the salmon sanctuary on Blue Creek and a tribal community forest that would help fund its existence.
From the early stages of this decade-long project, Moyle played an important role as a board member at Western Rivers Conservancy, encouraging the organization to push forward, providing letters of support, and speaking about and advocating for the project. The salmon sanctuary was completed in 2018, protecting the entire lower Blue Creek watershed for salmon and steelhead.
Of all of Moyle’s work in California, though, he is probably best known for his studies of Delta smelt in the Sacramento–San Joaquin River Delta, especially at Suisun Marsh. Suisun is the largest uninterrupted estuarine marsh in North America, and Moyle began studying its fishes shortly after he arrived in California. Every month, for over four decades, Moyle and a research partner took a small boat out to capture fish and observe how the marsh has been changing over time.
“If you go back to Peter’s first edition of Inland Fishes of California and you read his description, he talks about how abundant they were,” said Andrew Rypel, associate professor in UC Davis’s Department of Wildlife, Fish, and Conservation Biology and a colleague of Moyle’s. “Over time, they started going away, and it is now likely they’re going to go extinct within the next ten years.”
No one has done more to try to stave off their extinction than Peter Moyle. Because he spent decades studying them, he was able to successfully secure their protection under the California Endangered Species Act, and later the federal Endangered Species Act.
“When the species was being listed,” said Rypel, “there were implications for water users, and Peter had a bullseye on his back. He even received death threats. It’s this dinky little fish that no one cared about, but Peter cared about it. How many biologists would keep working on something like this when their family is getting death threats? It’s an incredible story of bravery and conservation.”
The Suisun Marsh is just one of the places that Moyle devoted his life to understanding. Over the course of 50 years, he has made annual pilgrimages into the same remote trout streams, returned to the same marshes and estuaries, yielding an unprecedented body of knowledge of how fish adapt to changing conditions over time. When it comes to managing California’s rivers away from the march toward fish extinction, especially in the face of climate change, that knowledge is proving pivotal.
This close attention that Moyle pays to the smaller things, to the fish and streams that others overlook, to the Delta smelt and the Putah Creeks, are what make him so unique. And it’s had a big impact on many California rivers.
“We were discussing a project on the Gualala River at a board meeting recently,” said Doroff. “We saw this river as crucial for salmon and steelhead, and then Peter, in quintessential Peter Moyle style, chimed in with, ‘Let’s not forget about the Gualala roach!’”
The Gualala roach is a small fish endemic to the Gualala River, and only a handful of people on the planet have even heard of it. But Moyle knows it, just as he seems to know every fish in every single tributary across the state. And he knows how important this obscure little fish is to the bigger picture, especially when it comes to healthy rivers and the future of our streams.
Danny Palmerlee is communications director for Western Rivers Conservancy.