The Delta smelt is an endangered 3-inch fish that is found only
in the Sacramento-San Joaquin Delta. The smelt’s tendency to swim
near the State Water Project and Central Valley Project export
pumps in the South Delta has complicated water deliveries to
farmers and cities.
Late last summer, on August 29th, 2024, the United States Fish
and Wildlife Service listed the San Francisco Bay-Delta
distinct population segment of longfin smelt (Spirinchus
thaleichthys) as ‘endangered’ under the federal Endangered
Species Act (ESA). With this decision, the Longfin Smelt joins
the Delta Smelt (Hypomesus transpacificus), the longfin’s
infamous cousin species, as a list species under the
ESA. Longfin smelt had already been listed as ‘threatened’
under the California Endangered Species Act (CESA), but the new
federal listing is a sign of the challenges that smelt and the
broader Delta ecosystem face. The listing brings additional
protections and new regulatory requirements that may further
complicate water management in the Delta. This blog post
provides an overview of this population of Longfin Smelt,
explains what listing means, and then discusses ongoing work at
UC Davis and beyond to recover Longfin Smelt populations.
The most powerful man in the world is waging war on a tiny,
almost extinct fish. The fish is the minnow-like delta
smelt, less than three inches long with a lifespan of only a
year. Its sole natural habitat is the Sacramento-San Joaquin
River Delta – a marshy maze of more than 1,100 miles of
waterways, levees and islands where its namesake rivers
intertwine. … It has become a flashpoint in the California
water wars – the never-ending debate over the best use of a
scarce resource in a state burdened with recurrent drought,
wildfires, and the climate crisis. Now Trump is seizing control
of the debate – regulations and the truth be damned. –Written by columnist Bill Walker
President Donald Trump’s vow to put “people over fish” in
Southern California by shifting water to the region’s farmers
could deal a new blow to struggling commercial, sport and
tribal fishermen who have coped for years with decimated salmon
populations. On the cusp of the anticipated third annual
closure for salmon fishing in California — with an official
decision due out next month from the Pacific Fishery Management
Council — many are raising concerns that Trump’s vow to divert
more water from the San Francisco Bay Delta and its watershed
could further cripple their industry.
The federal government has restored funding for a captive
breeding program designed to ensure survival of California’s
delta smelt, even as President Donald Trump has sharpened
criticism of the endangered fish. A five-year grant for the UC
Davis Fish Conservation and Culture Laboratory in Contra Costa
County, which raises the smelt, expired last month, and many
believed the funding would not be reinstated. Eleven of the
lab’s 17 employees were let go. This week, the U.S. Bureau of
Reclamation and UC Davis confirmed that the federal funding,
which makes up about three-quarters of the lab’s budget, would
resume. Why the financing lapsed and why it ultimately returned
amid the widespread funding cuts initiated by the Trump
administration over the past two months was not immediately
clear.
The Water Education Foundation has
unveiled an
interactive online tour of the Sacramento-San
Joaquin Delta that offers viewers and readers a broad overview of
the heart of California water – its history and development, its
importance as an ecological resource and water hub and the array
of challenges it faces.
Titled “Exploring the Heart of California Water,” the online
tour, built as a story map, guides readers and viewers through
different facets of the Delta. It includes the Delta’s history
and the people – including the Native American tribes – who have
lived there, the fish and wildlife that depend on its waters and
its role as a crossroads for federal, state and local water
projects.
In the vast labyrinth of the West
Coast’s largest freshwater tidal estuary, one native fish species
has never been so rare. Once uncountably numerous, the Delta
smelt was placed on state and federal endangered species lists in
1993, stopped appearing in most annual sampling surveys in 2016,
and is now, for all practical purposes, extinct in the wild. At
least, it was.
This tour guided participants on a virtual journey deep into California’s most crucial water and ecological resource – the Sacramento-San Joaquin Delta. The 720,000-acre network of islands and canals support the state’s two major water systems – the State Water Project and the Central Valley Project. The Delta and the connecting San Francisco Bay form the largest freshwater tidal estuary of its kind on the West coast.
Bruce Babbitt, the former Arizona
governor and secretary of the Interior, has been a thoughtful,
provocative and sometimes forceful voice in some of the most
high-profile water conflicts over the last 40 years, including
groundwater management in Arizona and the reduction of
California’s take of the Colorado River. In 2016, former
California Gov. Jerry Brown named Babbitt as a special adviser to
work on matters relating to the Sacramento-San Joaquin Delta and
the Delta tunnels plan.
Does California need to revamp the way in which water is dedicated to the environment to better protect fish and the ecosystem at large? In the hypersensitive world of California water, where differences over who gets what can result in epic legislative and legal battles, the idea sparks a combination of fear, uncertainty and promise.
Saying that the way California manages water for the environment “isn’t working for anyone,” the Public Policy Institute of California (PPIC) shook things up late last year by proposing a redesigned regulatory system featuring what they described as water ecosystem plans and water budgets with allocations set aside for the environment.
Deepen your knowledge of California water issues at our popular
Water
101 Workshop and jump aboard the bus the next day to
visit the Sacramento-San Joaquin Delta, a 720,000-acre
network of islands and canals that supports the state’s water
system and is California’s most crucial water and ecological
resource.
Zooplankton, which are floating
aquatic microorganisms too small and weak to swim against
currents, are are important food sources for many fish species in
the Delta such as salmon, sturgeon and Delta smelt.
California should take immediate actions to save the endangered
Delta smelt from extinction, a top fish scientist said recently.
Peter Moyle, distinguished professor emeritus in the Department
of Wildlife, Fish and Conservation Biology at the University of
California, Davis, has been studying the health of California’s
native fish since 1969. He told an audience in Sacramento that
it’s time for stepped-up actions to save the Delta smelt, the
population of which has dropped to a historic low level.
The 2012 landmark Colorado River Basin Study identified a major
disparity between future water supply and demand, and established
three workgroups to figure out how to close the gap. The newest
issue of Western Water magazine takes a look at the process and
progress in the last two years.
This 3-day, 2-night tour, which we do every year,
takes participants to the heart of California water policy – the
Sacramento-San Joaquin Delta and San Francisco Bay.
This 25-minute documentary-style DVD, developed in partnership
with the California Department of Water Resources, provides an
excellent overview of climate change and how it is already
affecting California. The DVD also explains what scientists
anticipate in the future related to sea level rise and
precipitation/runoff changes and explores the efforts that are
underway to plan and adapt to climate.
15-minute DVD that graphically portrays the potential disaster
should a major earthquake hit the Sacramento-San Joaquin Delta.
“Delta Warning” depicts what would happen in the event of an
earthquake registering 6.5 on the Richter scale: 30 levee breaks,
16 flooded islands and a 300 billion gallon intrusion of salt
water from the Bay – the “big gulp” – which would shut down the
State Water Project and Central Valley Project pumping plants.
Water truly has shaped California into the great state it is
today. And if it is water that made California great, it’s the
fight over – and with – water that also makes it so critically
important. In efforts to remap California’s circulatory system,
there have been some critical events that had a profound impact
on California’s water history. These turning points not only
forced a re-evaluation of water, but continue to impact the lives
of every Californian. This 2005 PBS documentary offers a
historical and current look at the major water issues that shaped
the state we know today. Includes a 12-page viewer’s guide with
background information, historic timeline and a teacher’s lesson.
Water as a renewable resource is depicted in this 18×24 inch
poster. Water is renewed again and again by the natural
hydrologic cycle where water evaporates, transpires from plants,
rises to form clouds, and returns to the earth as precipitation.
Excellent for elementary school classroom use.
This 24×36 inch poster, suitable for framing, explains how
non-native invasive animals can alter the natural ecosystem,
leading to the demise of native animals. “Unwelcome Visitors”
features photos and information on four such species – including
the zerbra mussel – and explains the environmental and economic
threats posed by these species.
This 24×36 inch poster, suitable for framing, explains how
non-native invasive plants can alter the natural ecosystem,
leading to the demise of native plants and animals. “Space
Invaders” features photos and information on six non-native
plants that have caused widespread problems in the Bay-Delta
Estuary and elsewhere.
The 24-page Layperson’s Guide to the Delta explores the competing
uses and demands on California’s Sacramento-San Joaquin Delta.
Included in the guide are sections on the history of the Delta,
its role in the state’s water system, and its many complex issues
with sections on water quality, levees, salinity and agricultural
drainage, fish and wildlife, and water distribution.
Pelagic fish are those that live near the water’s surface rather
than on the bottom. In California, pelagic fish species include
the Delta smelt, longfin
smelt, striped bass and salmon.
In California, the fate of pelagic fish has been closely tied to
the use of the water that supports them.
The endangered Delta smelt is a 3-inch fish found only in the
Sacramento-San
Joaquin Delta. It is considered especially sensitive because
it lives just one year, has a limited diet and exists primarily
in brackish waters (a mix of river-fed fresh and salty ocean
water that is typically found in coastal estuaries).
This issue of Western Water looks at the BDCP and the
Coalition to Support Delta Projects, issues that are aimed at
improving the health and safety of the Delta while solidifying
California’s long-term water supply reliability.
This printed issue of Western Water examines the issues
associated with the State Water Board’s proposed revision of the
water quality Bay-Delta Plan, most notably the question of
whether additional flows are needed for the system, and how they
might be provided.
This printed issue of Western Water examines science –
the answers it can provide to help guide management decisions in
the Delta and the inherent uncertainty it holds that can make
moving forward such a tenuous task.
This printed issue of Western Water provides an overview of the
idea of a dual conveyance facility, including questions
surrounding its cost, operation and governance
This printed copy of Western Water examines the Delta through the
many ongoing activities focusing on it, most notably the Delta
Vision process. Many hours of testimony, research, legal
proceedings, public hearings and discussion have occurred and
will continue as the state seeks the ultimate solution to the
problems tied to the Delta.
There are multiple Delta Vision processes underway and a decision
on the future of the Delta will be made in the next two years.
Unlike past planning efforts that focused primarily on water
resource issues and the ecosystem, these current efforts are
expanding to include land use planning, recreation, flood
management, and energy, rail and transportation infrastructure.
How – or if – all these competing demands can be accommodated is
the question being considered.
This issue of Western Water discusses the CALFED Bay-Delta
Program and what the future holds as it enters a crucial period.
From its continued political viability to the advancement of best
available science and the challenges of fulfilling the ROD, the
near future will feature a lively discussion that will play a
significant role in the program’s future.
