Posts Tagged: Peter Moyle
California once teemed with millions of native salmon, trout and steelhead. The state has 31 distinct types of these iconic, majestic fish. But decades of degradation to aquatic habitat has depleted their numbers in many areas of the state. According to a report by UC Davis fisheries professor Peter Moyle and colleagues, 20 of these fish species are in danger of extinction within the next century. They are important species not just for the recreational or commercial benefits they afford, but also because they are a direct reflection of the health of the environment.
“Large self-sustaining populations of native salmon and trout are found where streams are in reasonably good condition,” Moyle wrote in his 2008 report, “SOS: California's Native Fish Crisis.” This report was commissioned by the conservation organization California Trout (CalTrout), which exists to support conservation science, education, and advocacy efforts to protect California's water resources and fisheries.
Moyle, whose academic home is the Department of Wildlife, Fish and Conservation Biology at UC Davis, is no stranger to CalTrout. He is the foremost authority on California's native freshwater and anadromous (sea-run) fishes and has been a leader in research and conservation efforts. His research has provided the core science essential to statewide conservation planning for freshwater and estuarine native fishes, especially salmon and trout. Graduate students who studied with Moyle now occupy many top-level fish ecologist and management positions in state and federal agencies, as well as key nonprofits like CalTrout.
In May of this year CalTrout and UC Davis announced the formal creation of the Peter B. Moyle and California Trout Endowed Chair in Cold Water Fishes. The endowment will provide crucial support for the chair holder's scholarly activities, teaching, and public service involving cold water fish and aquatic ecosystems. He or she will teach department courses, mentor graduate students, conduct research and outreach, and provide leadership in the conservation of cold water fishes and their ecosystems. The university recognizes that salmon, trout, and steelhead are the major drivers of many conservation efforts and will have the highest priority in the chair's program.
Most of the contributors to the endowment are CalTrout board members such as Nick Graves. He and his wife, Mary, explored many trails and trout waters in the Sierra Nevada over the years and have enjoyed larger rivers flowing from the Trinity Alps, Mt. Shasta, and the Siskiyou Mountains. “The opportunity to create a scientific chair whose research targets California waters, in perpetuity, is a comforting thought,” Graves said.
“I have worked with the organization since its earliest days and have always admired the dedication of its members to aquatic conservation,” Moyle said. “I am biased, of course, but I think CalTrout has made a very smart investment in the future by creating an endowed chair.”
You don't have to dig too deep into the scientific literature and popular media to find perspectives on threats posed to biodiversity in California and around the globe. Two UC Davis scientists in the Department of Wildlife, Fish and Conservation Biology have published fresh insights into endangered species in recent months.
Endangered Species Act sets a high standard
, professor in the Department of Wildlife, Fish and Conservation Biology, is a renowned expert on California's native fish. He used the occasion of the 40th anniversary of the passage of the federal Endangered Species Act (ESA) in December 2013 to size up how the act influenced his own research and how some of California's aquatic biota have fared.
After passage of the ESA, Moyle and his graduate students initially searched for three species they suspected were in trouble: Modoc sucker, rough sculpin and bull trout. They found the sucker in trouble but easy to protect, the sculpin reasonably secure, and the bull trout near extinction in California. It has since vanished.
"As an untenured professor then, I thought it a bit risky to base a career on finding rare fish," Moyle wrote in an opinion piece published in The Sacramento Bee. “So I also undertook a study of Delta and longfin smelt, which at the time were two of the most abundant fish in the Sacramento–San Joaquin Delta.”
Moyle began a monthly sampling program to keep track of smelt populations and other fish in the Suisun Marsh. A few years later smelt counts dropped dramatically. The data eventually led to the U.S. Fish and Wildlife Service listing the Delta smelt as a “threatened” species under the ESA.
His ongoing research has recorded a statewide decline of most native fishes. With other researchers, Moyle has just completed detailed accounts of the biology and status of more than 60 native fishes — all potential candidates for ESA listings. This study will soon be released by the California Department of Fish and Wildlife.
“Most of our recommendations for preventing extinctions call for more and better water for the fish, or at least for protecting existing water they depend on,” Moyle said. “Funny how it almost always comes down to fish needing water.
“The Endangered Species Act sets a high standard in this regard because it not only forbids extinction; it also mandates recovery of each species to a more sustainable state.”
Moyle's opinion piece can be viewed in its entirety here.
Human longevity an indicator of endangered species
is a postdoctoral scholar who has previously worked with other UC Davis scientists in the development of conservation and management plans for reptiles and amphibians in California. Recently he was involved in a study published last fall in the journal Ecology and Society on the social and ecological predictors of global invasions and extinctions.
The researchers analyzed data from 100 countries, representing 87 percent of the world's population. They examined 15 social and ecological variables, such as tourism, per capita gross domestic product, water stress and political stability. The study showed that as human life expectancy increases, so does the percentage of invasive and endangered birds and mammals.
“It's not a random pattern,” Lotz said. “Out of all this data, that one factor — human life expectancy — was the determining factor for endangered and invasive birds and mammals.”
New Zealand, the United States and the Philippines had among the highest percentages of endangered and invasive birds. The study has been reported in the Los Angeles Times and other news media. Read more about the study's findings in our news release here. The journal article can be viewed here.
The study, published online in May in the journal PLOS ONE, assessed how vulnerable each freshwater species is to climate change and estimated the likelihood that those species would become extinct in California within 100 years.
The researchers found that, of 121 native fish species, 82 percent are likely to be driven to extinction or very low numbers as climate change speeds the decline of already depleted populations. In contrast, only 19 percent of the 50 non-native fish species in the state face a similar risk of extinction.
“If present trends continue, much of the unique California fish fauna will disappear and be replaced by alien fishes, such as carp, largemouth bass, fathead minnows and green sunfish,” said Moyle, who has been documenting the biology and status of California fish for the past 40 years.
“Disappearing fish will include not only obscure species of minnows, suckers and pupfishes, but also coho salmon, most runs of steelhead trout and Chinook salmon, and Sacramento perch,” Moyle said.
Fish requiring cold water, such as salmon and trout, are particularly likely to go extinct, the study said. However, non-native fish species are expected to thrive, although some will lose their aquatic habitats during severe droughts and low-flow summer months.
The top 20 native California fish most likely to become extinct in California within 100 years as the result of climate change include (asterisks denote a species already listed as threatened or endangered):
- Klamath Mountains Province summer steelhead
- McCloud River redband trout
- Unarmored threespine stickleback*
- Shay Creek stickleback
- Delta smelt*
- Long Valley speckled dace
- Central Valley late fall Chinook salmon
- Kern River rainbow trout
- Shoshone pupfish
- Razorback sucker*
- Upper Klamath-Trinity spring Chinook salmon
- Southern steelhead*
- Clear Lake hitch
- Owens speckled dace
- Northern California coast summer steelhead
- Amargosa Canyon speckled dace
- Central coast coho salmon*
- Southern Oregon Northern California coast coho salmon*
- Modoc sucker*
- Pink salmon
The species are listed in order of vulnerability to extinction, with No. 1 being the most vulnerable.
Climate change and human-caused degradation of aquatic habitats is causing worldwide declines in freshwater fishes, especially in regions with arid or Mediterranean climates. These declines pose a major conservation challenge. However, there has been little research in the scientific literature related to the status of most fish species, particularly native ones of little economic value.
Moyle saw the need for a rapid and repeatable method to determine the climate change vulnerability of different species. He expects the method presented in the study to be useful for conservation planning.
“These fish are part of the endemic flora and fauna that makes California such a special place,” said Moyle. “As we lose these fishes, we lose their environments and are much poorer for it.”
Co-authors of the study were postdoctoral students Joseph Kiernan, Patrick Crain and Rebecca Quiñones of the Center for Watershed Sciences at UC Davis. Funding for the study was provided by the California Energy Commission.
Media coverage of the study includes: