Invasive species, also known as exotics, are plants, animals,
insects, and aquatic species introduced into non-native habitats.
Without natural predators or threats, these introduced species
Often,invasive species travel to non-native areas by ship,
either in ballast water released into harbors or attached to the
sides of boats. From there, introduced species can then spread
and significantly alter ecosystems and the natural food chain as
they go. Another example of non-native species introduction
is the dumping of aquarium fish into waterways.
Invasive species also put water conveyance systems at risk. Water
pumps and other infrastructure can potentially shut down due to
large numbers of invasive species.
Seven years ago, after the fish died, Sarah Ryan decided she
couldn’t wait any longer for help. California at the time
was in the depths of its worst drought in the last millennium
and its ecosystems were gasping. For Ryan, the fish kill in
Clear Lake, the state’s second largest and the centerpiece of
Lake County, was the last straw. Ryan is the environmental
director for Big Valley Rancheria, a territory of the Big
Valley Band of Pomo Indians that sits on the ancient
lake’s western shore. She and others raised alarms for several
years about increasingly dire blooms of toxic
Wild horses and donkeys are often considered a problem in the
American West, but new research suggests their penchant for
digging wells with their hooves offers benefits to the
ecosystems they inhabit, reports Douglas Main for National
Geographic. The study, published this week in the journal
Science, shows that when wild or feral horses and donkeys dig
wells, they increase the availability of water for other
species living in the parched desert landscape. These wells can
be up to six feet deep and provide access to groundwater to
species including badgers, mountain lions, deer and birds.
As we rapidly enter another drought, long-standing questions on
ecological impacts of increased temperatures, reduced water
levels and flows re-emerge. This reality recently reminded me
of some of my own previous work looking at growth rate
variations of largemouth bass in response to droughts in the
southeastern USA (Rypel et al. 2009). Results from this work
may be useful/interesting for biologists and managers in
California considering similar questions.
Amid the extreme aridity of the vast Colorado Desert of eastern
San Diego County, a ribbon of greenery allows life to thrive.
The Sentenac Cienega area inside Anza-Borrego Desert State Park
is more than 100 miles southeast of Irvine. It contains a
desert wetland, which is part of the San Felipe Creek watershed
that is fed by nearby mountains and ultimately flows into the
Salton Sea. But the wetland is sick from invasive, non-native
plants, and its water levels are dangerously low. Researchers
from UCI are trying to figure out why.
Lake Tahoe is known for its mesmerizing clear, blue water.
But there are multiple threats to the lake that may
someday change the color and worse, downgrade the quality
of the water. Some of the most difficult of these threats to
address are invasive species, specifically two types of
aquatic plants that are not native and are moving from an area
of the lake known as the Tahoe Keys into Lake Tahoe
itself. The plants are Eurasian watermilfoil and
Suisun Marsh is central to the health of the San Francisco
Estuary. Not only is it a huge (470 km2) tidal marsh in
the center the northern estuary (Figure 1), but it is an
extremely important nursery area for species such as splittail,
striped bass, longfin smelt, and, formerly, delta smelt. Since
January 1980, a team from The University of California, Davis,
in partnership with the California Department of Water
Resources (DWR), has systematically monitored the marsh’s fish
populations. The team had been sampling the fish and
invertebrates every month with trawls and beach seines, with a
nearly unbroken record. Then Covid-19 restrictions settled
It’s nothing less than an invasion. Interlopers are coming
into California by land, by sea…and by FedEx. That’s what
happened with the European green crab, a voracious
cannibal that stowed away in packages of worms sent by
overnight delivery to commercial fisherman in California.
Unknown to anyone, the tiny crustaceans were concealed in
seaweed that wrapped the cargo and were freed into the Pacific
when fishermen tossed it overboard. … California spends
$3 million a year attempting to eradicate nutria, a large,
homely, orange-toothed rodent that destroys wetlands and bores
holes into levees. Another $3 million a year goes to educating
boaters about quagga mussels, which hitch rides on hulls and
cling to equipment in the state’s vast water transport
system. And, for the last 20 years, authorities have
spent more than $34 million to manage Atlantic cordgrass in the
San Francisco Bay-Delta.
In anticipation of this week’s Bay-Delta Science Conference, I
thought it would be useful to consider some of what it takes to
understand a complex ecosystem like an estuary and to encourage
everyone working in the San Francisco Estuary – scientists,
policymakers, and local stakeholders – to continue shifting our
ecosystem management focus from the simple to the complex. I’ll
explain why in a moment. Here are four suggestions for
improving ecosystem management in the San Francisco Bay-Delta:
The Delta Stewardship Council (Council) announced the hiring of
Ryan Stanbra, the Council’s legislative and policy advisor, to
the key post of chief deputy executive officer. … Appointed
by Governor Brown in 2015, Ryan joined the Council in the role
of legislative and policy advisor. He has played a pivotal role
in advising on critical Council initiatives like implementation
of reduced reliance on the Delta, interagency coordination and
outreach for the Delta Levees Investment Strategy, increasing
funding for critical science investments, and more. He has
served in the acting chief deputy executive officer role since
The Division of Boating and Waterways (DBW) today announced
plans for this year’s control efforts for aquatic invasive
plants in the Sacramento-San Joaquin Delta and its southern
tributaries. Consistent with COVID-19 safety protocols, DBW
personnel started herbicide treatments today to help control
several invasive plants found in the Delta. … The
invasive plants include water hyacinth, South American
spongeplant, Uruguay water primrose, Alligator weed, Brazilian
waterweed, curlyleaf pondweed, Eurasian watermilfoil, hornwort
(aka coontail), and fanwort.
The Division of Boating and Waterways (DBW) will be accepting
grant applications for quagga and zebra mussel infestation
prevention programs from March 22 through April 30,
2021. All applications must be received by 5 p.m. on
Friday, April 30, 2021. … California water body
authorities have recognized the westward spread of mussel
infestation via the Colorado River System and the potential
harm to state waterways should lakes and reservoirs become
invaded. To help prevent California waterways from infestation,
DBW provides grants to entities that own or manage any aspect
of water in a reservoir that is open for public recreation and
Crews on Lake Tahoe’s South Shore continue work to remove
aquatic invasive plants from the Taylor Creek and Tallac Creek
marshes. A new fence was recently installed around the project
area and officials are asking recreators to respect the
protected area for safety and to ensure the greatest chance of
success for the project, the Tahoe Regional Planning Agency
said in a press release. The fencing is intended to protect
large tarps that will be staked to the marsh bottom as part of
a project to remove Eurasian watermilfoil from the marsh
Some invasive species targeted for total eradication bounce
back with a vengeance, especially in aquatic systems, finds a
study led by the University of California, Davis. The study,
published in the journal PNAS, chronicles the effort — and
failure — to eradicate invasive European green crabs from a
California estuary. The crabs increased 30-fold after about 90
percent had been removed. The study is the first experimental
demonstration in a coastal ecosystem of a dramatic population
increase in response to full eradication. … For the PNAS
study, researchers in 2009 began intensive efforts to eradicate
the European green crab from Stinson Beach’s Seadrift
The effort to return [California red-legged] frogs to
Southern California, which had been ongoing by Robert
Fisher from the U.S. Geological Survey’s Amphibian
Research and Monitoring Initiative Program for more than 20
years, began to move the needle in San Diego County when
Winchell started working with private ranchers Judy and Chuck
Wheatley who had just restored a pond on their property for the
reintroduction of the Western pond turtle. … The species was
decimated by disease and invasives, and disappeared from San
Diego County in 1974 and western Riverside County in
Zebra mussels — fingernail-sized mollusks named for their
striped shells — are benign in their native Black Sea and
Caspian Sea ecosystems. But they are disastrous almost
everywhere else. Since they were first discovered in the
Great Lakes in 1986, these rapid-spawning animals have
infested every watershed in the Lower 48 except the
Columbia River Basin….The mussel found in [a pet store in]
Seattle came from the California distributor….
The Board of Supervisors will hear the latest this week on the
program that aims to prevent destructive mussels from infesting
Clear Lake and will consider a proposal to extend a contract
for using the former juvenile hall as a temporary support
shelter for the county’s homeless residents. The meeting
will begin at 9 a.m. Tuesday, March 9, and will be
available to the public virtually only.
California’s rivers, wetlands, and other freshwater ecosystems
are in poor health. Water management practices, pollution,
habitat change, invasive species, and a changing climate have
all taken a toll, leaving many native species in dire straits.
And the current approach for managing freshwater ecosystems is
not working. In this video Jeff Mount, senior fellow at the
PPIC Water Policy Center, discusses the many benefits these
ecosystems bring to California, and outlines a path for
improving their condition to secure these benefits for future
The southern western pond turtle, San Diego’s only native
freshwater turtle, is becoming rarer and rarer in coastal
Southern California. These pond turtles are competing against
other recently introduced animals such as bullfrogs and
largemouth bass, and especially released pets such as other
turtles. Do NOT release pet turtles, or any other type of pet,
into the wild as they often eat the smaller southern western
pond turtle’s natural food and even their hatchlings, said Ms.
Mallory Lindsay of Ms. Mallory Adventures. Other non-native
turtle species can be found in the region such as snapping
turtles, softshell turtles, and red-eared sliders.
[S]cientists were having a hard time telling delta smelt apart
from a fish species from Japan called wakasagi.
… Wakasagi were introduced by the government in the
1950s. There’s no shortage of them here or in Japan. Especially
when they’re young, to the naked eye they look virtually
identical to deltas. They’re so similar, in fact, to the
nearly extinct fish that scientists were worried about
hybridization — that this plentiful species and the delta smelt
would start hooking up, making mixed-species fish babies.
The Center for Biological Diversity filed a notice of intent
today to sue the U.S. Fish and Wildlife Service seeking
Endangered Species Act protection for the Clear Lake hitch, a
large minnow found only in Northern California’s Clear Lake and
its tributaries. The Trump administration denied the fish
protection in a December 2020 determination.
Conservation groups said 80 species were known to have gone
extinct, 16 in the last year alone. Millions of people rely on
freshwater fish for food and as a source of income through
angling and the pet trade. But numbers have plummeted due to
pressures including pollution, unsustainable fishing, and the
damming and draining of rivers and wetlands. The report said
populations of migratory fish have fallen by three-quarters in
the last 50 years. Over the same time period, populations of
larger species, known as “megafish”, have crashed by 94%.
A restoration project for the long-suffering Ballona Wetlands
is moving forward after the California Department of Fish and
Wildlife certified the final Environmental Impact Report for
the Ballona Wetlands Ecological Reserve last year. Years
of neglect, human impact, and development took a toll on the
wetlands for years. The project aims to remove invasive
plants and leftover fill from the development of Marina Del
Rey, re-establish a functioning floodplain, and create natural
levees for flood protection against sea level rise.
For the better part of the last two centuries, the
Sacramento-San Joaquin Delta has been modified in any number of
ways to meet the demands of Californians. But a new
wide-ranging study looks at what might be the most serious
Delta threat that doesn’t come in the form of an excavator –
In the Tahoe Keys—a neighborhood of houses and artificial
lagoons with easy boat access to Lake Tahoe, one of America’s
least polluted lakes—the water is not blue but a murky mass of
green, filled with invasive weeds. Dogs have died from swimming
in the canals, which is prone to toxic algae blooms. Activists
want to wall the Keys off from the lake. The neighborhood
association is proposing to tackle the problem with herbicides,
which have never been used before in Lake Tahoe.
BlueGreen Water Technologies has secured approval from the
California Department of Pesticide Regulation for its
algaecide, Lake Guard Oxy, for commercial application in the US
state. According to the firm, in the past year, there has
been a marked rise in the severity of toxic algal blooms, also
called as ‘blue green algae’ and ‘red tide’ in several of the
state’s lakes as well as on the coasts.
Deltas globally adjust with changes and fluctuations in
external conditions, internal dynamics, and human
management. This is a short history of big changes to
California’s Sacramento-San Joaquin Delta (Delta) in the past
and present, and its anticipated future. This history is
important for understanding how many of the Delta’s problems
have developed, changed, and continue to change.
It was daybreak and Barron Tsinigine had been fishing for
rainbow trout, until he found out he could earn $25 for landing
a brown trout. That’s when his plan changed. … Tsinigine was
one of the first anglers to participate in Arizona’s
incentivized harvest of brown trout … in hopes of keeping the
predacious trout from moving downstream and endangering native
fish, like the humpback chub.
The Kings River Conservation District, along with co-applicant
Tulare Lake RCD, received this grant to help remove invasive
species and debris from levees and riverbank along the Kings
River, improve water flow, strengthen flood protection,
increase carbon capture, and improve delivery of clean water to
Not only are non-native predators abundant, but predation risk
may be compounded by the prevalence of invasive vegetation such
as Brazilian waterweed (Egeria densa). These non-native plants
may deal a double blow to Chinook salmon by restricting their
access to formerly open-water habitat and by providing
predators like largemouth bass an edge in a habitat they are
President Trump’s signature on a bill expanding the fight
against a large, vexatious rodent called the nutria is an
instructive victory for a newly reelected Democrat from a swing
district in California’s San Joaquin Valley.
The pesky 3-foot-long, buck-toothed nutria is getting the
better of California. The large rodent is chewing up rivers and
wetlands and threatening to mow down farmland and
infrastructure, and the state is struggling to contain
it. Relief may be on the way.
Radically transformed from its ancient origin as a vast
tidal-influenced freshwater marsh, the Sacramento-San Joaquin
Delta ecosystem is in constant flux, influenced by factors
within the estuary itself and the massive watersheds that drain
though it into the Pacific Ocean. Lately, however, scientists
say the rate of change has kicked into overdrive…
It’s been a busy spring and summer for trapping nutria in
Merced and Stanislaus counties. State Fish and Wildlife have
caught nearly 1,000 nutrias along the San Joaquin River
corridor and in the grasslands.
Join us as we guide you 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.
Volunteer citizen scientists working with the League to Save
Lake Tahoe conducted surveys of Donner and Spooner lakes to
detect aquatic invasive species, and restored native wetland
habitat in Johnson Meadow in September. Both efforts are aimed
at preserving the Tahoe-Truckee region’s unique ecology.
Congress has given final approval to a bill that would take on
nutria, a giant rodent threatening waterways in the Central
Valley and beyond. … The measure, HR 3399, would provide $12
million to California and several other affected states for
nutria control, research and related efforts.
The collaborative design process for the Franks Tract Futures
project brought initially skeptical local stakeholders on board
and is being hailed as a model for future initiatives. Yet
major uncertainties remain as interested parties explore the
challenges of implementing a complex redesign of a big chunk of
Groups in the Tahoe Basin are using new technology to fight
invasive species and decreasing lake clarity. Researchers at
University of Nevada, Reno and Tahoe Regional Planning Agency
have been testing a UV light equipped vessel to control aquatic
invasive plants in the Tahoe Keys.
Many invasive species look similar to the local plants and
animals that belong in our backyards, deserts, forests and
streams. Despite their ability to blend in, invasive species
can be destructive to both native plants and animals, and
humans. Let’s compare a few invasive (and non-native) species
that look highly similar to some of their local, native
The Franks Tract Futures Project is asking for additional
comments on the State’s revised concept design.1 The project is
an outgrowth of the State’s 2016 Delta Smelt Resilience
Strategy, which recognized that Franks Tract is a death trap
for state and federally listed Delta smelt.
Because the invasive 20-pound rodents pose a unique threat to
California’s wetlands, the state has expanded the Nutria
Eradication Program over the past year to a staff of 26 field
operatives 100% dedicated to exterminating the swamp rat.
Unlike just about everything else in the state, the war against
nutria has been almost entirely unaffected by the coronavirus
The San Francisco Estuary is a dynamic and altered estuary that
supports a high diversity of fishes, both native and
non-native. … Since the 1950s, various agencies and UC Davis
have established long-term surveys to track the status of fish
populations. These surveys help scientists understand how
fishes are responding to natural- and human-caused changes to
The key to controlling the numbers of Lake Tahoe’s invasive
Mysis shrimp, which have been linked to a decline in clarity,
might be as simple as rewarding the family dog with a treat. A
team from UC Davis Graduate School of Management have
identified the shrimp as an ingredient for high-end dog treats
and are currently in the early phases of developing an initial
The new tool is a light fixture called an array mounted under a
working barge, which trolls the marina dousing the plants on
the bottom with UV-C light, a short-wave electromagnetic
radiation light that damages the DNA and cellular structure of
At the July meeting of the Delta Stewardship Council,
councilmembers heard briefings on the activities of the Delta
Protection Commission and the Delta Conservancy, and an update
on the Central Valley Flood Protection Plan.
Signal crayfish are displacing Shasta crayfish. Believed to
have already forced the sooty crayfish (Pacifastacus
nigrescens) to extinction, signal crayfish have outcompeted
their Shasta cousins to near extinction. However, a growing
trend of environmental monitoring, typically referred to as
eDNA, is helping scientists isolate the scarce species in an
effort to save it.
Our newest video features our ongoing project to study the
non-native fishes of the San Joaquin River in California’s
Central Valley. Non-native fishes outnumber natives in the San
Joaquin, but we know surprisingly little about them…
Senator Dianne Feinstein (D-Calif.) joined Senator John Kennedy
(R-La.) to introduce legislation to amend the Nutria
Eradication and Control Act. The legislation would authorize an
additional $6 million a year to increase assistance for states
that implement initiatives to eradicate the invasive species.
This new technology is an improvement on the existing bubble
curtain, providing more air and a much stronger application of
it. It also includes sea bins that will act like garbage cans,
collecting the fragments that are knocked free by the bubble
In 2003, Congress passed The Nutria Eradication and Control
Act, which established a fund to help Maryland and Louisiana
battle the animals. Recently, the House of Representatives
passed bipartisan legislation that now allows California to
also receive support. The bill now heads to the Senate.
In June 2018, scientists first noticed that aspen trees around
the basin were looking more defoliated than usual… “It was
concerning because, from a landscape diversity perspective,
aspens are so priceless in terms of what they contribute up
here,” said Will Richardson, executive director of the Tahoe
Institute for Natural Science.
Looking at the water hyacinth’s lovely lavender flowers and
lush green leaves, it’s easy to see why it was brought here
from South America. But too much of a good thing can cause
trouble, and few things turn into “too much” as quickly as
water hyacinths (Eichhornia crassipes).
Ben Ewing is an environmental scientist for CDFW’s North
Central Region. Based out of the region headquarters office in
Rancho Cordova, Sacramento County, Ben serves as the district
fisheries biologist for Alpine, Amador, Calaveras and Lake
California Rep. Josh Harder needed a way to convince the U.S.
House of Representatives to pay attention to his speech about
invasive species during a meeting in February. So he brought in
a hefty rat carcass and laid it on the table next to him. The
taxidermied rat … convinced the House to unanimously
pass a bill that supports eradication efforts in states
infested with nutria, large rodents also known as swamp rats
that are native to South America.
We want to know if removing carp can improve water quality and
reduce harmful algal blooms, HABs. Carp are widely known to
bioturbate sediments where previously deposited nutrients like
phosphorus are bound. Re-suspension of phosphorus by carp leads
to HABs, creating an interesting link between fish and human
The feasibility study refers to removal of Scott Dam as a
foregone conclusion. The reason being salmon and steelhead are
not able to access spawning grounds above the dam. This area is
a small percentage of the overall spawning habitat of the Eel
River watershed. … A fish ladder around Scott Dam makes much
Roland Knapp, research biologist at the University of
California Sierra Nevada Aquatic Laboratory, explained that a
fish-less habitat along with increased resistance to chytrid
fungus can allow populations to rebound and increase. Knapp’s
research findings have shown the frogs being able to adapt to
the disease over time. … “I have a lot of hope. I wouldn’t
have said that 10 years ago.”
Billions of invasive Mysis shrimp, introduced in the 1960s as a
food source for native trout, live in Lake Tahoe, where they
have almost eaten to extinction the native zooplankton that
historically helped keep the lake blue and clear.
The Bureau of Reclamation will begin using mussel-sniffing dogs
to inspect boats on the weekends this summer to help protect
New Melones Lake from invasive-aquatic species, such as quagga
or zebra mussels.
Discovery Bay residents are growing irritated with invasive
aquatic plants and the COVID-19 pandemic slowing down weed
abatement. While the town can be the ideal place to enjoy a
vacation lifestyle year-round, this spring’s crop of weeds is
ruining the bays and inhibiting movement around docks on the
west side of town.
California State Parks’ Division of Boating and Waterways on
Thursday announced plans to control aquatic invasive species in
the Sacramento-San Joaquin Delta. Beginning April 20, the DBW
will start herbicide treatments on floating aquatic vegetation
such as water hyacinth and alligatorweed, and submersed aquatic
vegetation such as Egeria densa and curlyleaf pondweed.
Given the historical resources dedicated to monitoring and
studying striped bass in the San Francisco Estuary, the
question must be asked: Why don’t we know more about what
they’re doing in the Pacific Ocean?
It is well known that warm water fish (bass and bluegill) have
diminished wild trout populations at Lake Tahoe. … However,
getting rid of the illegally planted warm water fish isn’t
altogether realistic, and the real agenda is only hinted at:
Protection for recently planted Cutthroat trout, declared as
the only ‘worthy’ fish allowed in the lake.
Rep. Josh Harder (D-CA) brought someone special with him to
push his nutria eradication bill on the House floor: a stuffed
giant “swamp rat” he obtained from the USDA nicknamed Nellie.
When Nellie was alive, she lived in Annapolis, Maryland.
The decision ends a 1996 policy that committed the state to
sustaining a population of about 1 million striped bass in the
Delta and other California waterways. They’re voracious,
nonnative predators that can weigh as much as 60 pounds.
They’re especially popular among anglers. It’s unclear exactly
how many striped bass are in the state, but the number is
believed to be fewer than 300,000.
If you live in Discovery Bay or the surrounding Delta area,
harmful algae blooms (HAB) are a well-known and unwelcome
presence each summer, but several local organizations are hard
at work, actively searching for a solution to the pernicious
In California’s never-ending water and fish wars, the striped
bass doesn’t get nearly the publicity as its celebrity
counterparts, the endangered Chinook salmon and Delta smelt.
Yet the striped bass is at the heart of a protracted fight over
California’s water supply, 140 years after the hard-fighting
fish, beloved by anglers, was introduced here from the East
Hydrilla (Hydrilla verticillata) is a highly invasive aquatic
plant that has the capacity, by forming dense mats that
restrict dissolved oxygen levels, to disrupt many of the
water-based activities that are synonymous with Lake County.
The factors causing the decline of many fish and fisheries in
the upper San Francisco Estuary have made their management
controversial, usually because of the correlation of declines
with increased water exports from the Delta and upstream of the
Delta… To address this problem better, the California Fish
and Game Commission is developing new policies for managing
Delta fish and fisheries, with a special focus on striped bass.
These changes will be substantial, multi-faceted, and often
rapid. Some changes will be irreversible. Many changes are
inevitable. Some will say today’s Delta is doomed. It will be
important for California to develop a scientific program that
can help guide difficult policy and management discussions and
decision-making through these challenges.
The people who guard the gulls that nest on Mono Lake’s islets
in the eastern Sierra Nevada have used dynamite, electric
fences and lawsuits to protect the birds from wily coyotes and
diversions of water to Los Angeles. … Now, the gulls are
facing a botanical invader they may not be able to overcome:
thickets of invasive weeds that have engulfed most of their
Dr. Rachel Johnson is a research biologist with the NOAA’s
National Marine Fisheries Service and UC Davis with over 15
years’ experience working on various aspects of conservation
and fisheries biology. In this presentation from the 2019 State
of the Estuary conference, Dr. Johnson discussed the importance
of developing a holistic framework among aquatic ecosystems and
Studies suggest that in the US alone, the introduction of
invasive mollusks into local ecosystems costs more that USD 6
billion per year. In an attempt to respond to this problem, the
state of California (which is perhaps one of America’s most
environmentally conscious states) has introduced the ‘Marine
Invasive Species Act’.
Through financial support from various grant funding, CDFA is
implementing a five-phase process for nutria eradication that
consists of survey, knockdown, mop-up, verification, and
surveillance. CDFW staff have been working the landscape by
dividing areas into 40-acre grids to ensure that nothing is
President Donald Trump’s administration rolled out an
aggressive plan Tuesday to ship more water from the Delta to
farmers in the San Joaquin Valley, a move that’s certain to
trigger lawsuits by environmentalists concerned about
endangered fish species.
Community members, supported by staff from the League to Save
Lake Tahoe, Tahoe Resource Conservation District and California
State Parks, have wrapped up a three-year effort to survey the
Upper Truckee River for aquatic invasive plants.
A recent “Sunday Morning” Moment of Nature highlighted brook
trout in the Sierra Nevada Mountains of California (see below).
With their bright red and orange abdomens, orange fins trimmed
in black, and sides sprinkled with yellow and red dots, they
flash through the water like little jewels.
Invasive fish species have long been a challenge for scientists
in the Grand Canyon because they attract fishermen but can
devour threatened native species. Now, the National Park
Service is ready to try a new approach to keeping things in
balance: pay fishermen and women to harvest one of the worst
offenders, the brown trout.
Pulling weeds is not usually a great way to start a party. But
filling a dumpster with invasive species was just the right
activity to commemorate the 10th anniversary of Tijuana River
Action Month on Saturday.
Just how far will Gov. Gavin Newsom go in his high-profile
fight with the Trump administration over environmental
protections? The next few months will provide an answer, as
Newsom is forced to take a stand on Trump rollbacks in a
long-contested battleground — the Northern California Delta
that helps supply more than half the state’s population with
drinking water and fills irrigation canals on millions of acres
One of the most recent threats to California’s environment has
webbed feet, white whiskers, shaggy fur and orange buck teeth
that could be mistaken for carrots. … The swamp rodents,
called nutria, are setting off alarms in California.
A rookie California lawmaker plans to haul a 20-pound rodent
carcass into Congress on Tuesday to press his colleagues for
money to fight an invasive species wreaking havoc on his
district. Rep. Josh Harder, D-Turlock, hopes a hearing on his
bill will convince his colleagues that funding to stop invasive
nutria in California’s Central Valley is sorely needed …
The Sacramento–San Joaquin Delta has more non-native species
than native ones, and its estuary is considered the most
invaded in the world. We talked to Jim Cloern—an emeritus
scientist with the US Geological Survey and an adjunct fellow
at the PPIC Water Policy Center—about this challenge.
There’s no certain answer as to how the nutria population
re-emerged after being declared eradicated in California
decades ago but the population is spreading and causing serious
concern. The Department of Fish and Wildlife was recently
awarded $10 million to wipe out the large, invasive rodents and
that effort is now well underway.
The common reed, Phragmites australis, is one of the most
invasive plants in the world, and its numbers are widespread in
Suisun Marsh. … Phragmites can change ecosystem structure by
increasing tidal habitat elevations and reducing overall
habitat quality, including disturbing the food chain by driving
out native plants in the Delta that support wildlife such as
waterfowl and the endangered salt marsh harvest mouse.
UC Davis researchers have seized on a new explanation for the
continued dinginess of Lake Tahoe’s blue waters — tiny invasive
shrimp. … To make Tahoe shrimp-free, the researchers are
proposing to remove the crustaceans with trawlers and to mass
market Omega-3 fatty acids extracted from the catch.
Nutria, a giant invasive rodent originally from South America,
might be the size of a beagle, but unlike a beagle you can’t
keep them in your home. The California Fish and Game Commission
is looking to correct a gap in the law that restricts what pets
may lawfully be owned by including nutria among the list.
As the sun sets across Lake Tahoe, UC Davis researcher Brant
Allen and his team lower their sonar machine into the lake.
Thousands of little purple dots rise across the screen as they
cross the lake. … It’s not fish or Tahoe Tessie; it’s a horde
of tiny mysis shrimp, which researchers think have been making
the lake murkier since they were introduced in the 1960s.
Rep. Josh Harder has focused much of his first year in office
on local issues such as water storage and the effects of almond
tariffs on Central Valley farmers. Now he is training his
attention on the nutria, a semi-aquatic rodent that has drawn
the ire of environmentalists, farmers and local officials
Native to South America, nutria pose a “triple threat” to
California’s future. The large, rat-like creatures are a
top-rated agricultural pest that threatens the state’s nearly
$50 billion farm economy. They destroy critical wetlands needed
by the native wildlife, like the Los Banos Wildlife Area, and
pose a public safety risk as their destructive burrowing can
damage water infrastructure like levees and canals.
Lake Tahoe, with its iconic blue waters straddling the borders
of Nevada and California, continues to face a litany of threats
related to climate change. But a promising new project to
remove tiny, invasive shrimp could be a big step toward
climate-proofing its famed lake clarity.
The initial objectives of the restoration project were to:
improve habitat for the Delta smelt, reduce saltwater
intrusion, reduce submerged aquatic weeds and reduce invasive
non-native fish species that feed on native fish. Carl Wilcox,
a CDFW policy advisor explained the objectives are now more
broad and include accommodations for recreational and economic
activities that are key to the region’s residents.
A growing menace in the form of 15-pound swamp rodents is
threatening Delta waterways, and the state is throwing money,
hunting dogs and birth control at the invasive pests which have
the potential to destroy crops and wetlands.
The rapid proliferation of the quagga mussel has major
implications for power plant reliability. The U.S. Bureau of
Reclamation installed a groundbreaking solution at Parker Dam
in Arizona that virtually eliminated the invasive species from
hydropower cooling systems.
Utah’s push to develop the $1.8 billion Lake Powell pipeline,
held up for years by political wrangling, funding feuds, reams
of red tape and massive amounts of paperwork, is now being
threatened by a tiny creature: the quagga mussel.
This event guided attendees 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.
The California Department of Fish and Wildlife (CDFW) today was
awarded $8.5 million in funding over three years by the
Sacramento-San Joaquin Delta Conservancy to expand its nutria
Besides choking out much-loved natives such as the golden
poppy, which is the state flower, Ward’s weed is a wildfire
hazard. Each year it dies off and turns into a brown mass of
thin, dry brush, like a tiny tumbleweed, that can go up in
flames with a spark.
The tall, bamboo-like plants clustered in dense thickets along
sections of the Salinas River in the Salinas Valley have long
attracted the attention of those who have strolled in that
area. Green and stately with long, sword-like leaves, they
belong to a species known as Arundo donax, or more commonly,
giant cane. … But the plant is a nuisance and local officials
have decided to do something about it.
An invasive bamboo-like species called arundo is encumbering
the natural ecology of the Salinas River and increasing flood
risk to nearby farmland. But the conservation agency charged
with protecting the area recently secured nearly $3 million
from state coffers for the purpose of fighting the invasion.
Bay Area anglers say they are pleased California State Parks is
drastically reducing the number of sites treated with
pesticides on the grass and weed-choked Sacramento-San Joaquin
River Delta. … The move to reduce spraying and pelleting on
parts of the Delta this year comes in the wake of last year’s
increased use of pesticides that anglers’s claim wiped out the
weeds, but also killed dozens of beavers, fish, turtles and
Conservationists and weekend volunteers have toiled in the
Bolsa Chica Wetlands for years, weeding out invasive plants and
replanting native vegetation squeezed out by the invaders. …
Now, these wildlife custodians are expanding their botanical
battle across Pacific Coast Highway to the sand dunes of Bolsa
Chica State Beach. After all, no matter how many enemy plants
are removed from the wetlands, ocean winds will carry more
seeds from non-native plants growing in the dunes.
For the past year the state’s worked to eradicate the rodents
for a second time. The rodents were brought to California in
the 1900s for the fur trade and fur farming. “[The] challenge
is we keep looking and we keep finding more nutria,” said Peter
Tira with the California Department of Fish and Wildlife.
“However, we do know there’s about 1.8 million acres of
suitable nutria habitat. This is the largest nutria eradication
ever attempted in the United States.”
On our Bay-Delta Tour June 5-7, participants will hear from a
diverse group of experts including water managers,
environmentalists, farmers, engineers and scientists who will
offer various perspectives on a proposed tunnel project that
would carry water beneath the Delta, efforts to revitalize the
Delta and risks that threaten its delicate ecological balance.
A pilot program that used ultraviolet light to combat aquatic
invasive plants has shown promising results. Results from the
program, which was deployed in Lakeside Marina in the summer of
2017, show the use of ultraviolet-C light successfully killed
submerged aquatic plants, according to the Tahoe Resource
More than 400 nutria have been captured in the first year of an
effort to eradicate the invasive South American rodent from
California. The state Department of Fish and Wildlife said
Monday the semi-aquatic rodents were trapped in five counties
in the San Joaquin Valley. Nutria are an agricultural pest,
destroy wetlands critical to native wildlife and threaten water
delivery and flood control infrastructure through destructive
Any new path on California water must bring Delta community and
fishing interests to the table. We have solutions to offer. We
live with the impacts of state water management decisions from
loss of recreation to degradation of water quality to
collapsing fisheries. For example, how can new and improved
technology be employed to track real time management of
In California, [Jerry] Schubel saw an opportunity to turn the
energy, food and water issues facing the state into a
sustainable model showing how people can live in harmony with
the Earth and the ocean, and thrive. That model required deep
collaboration, a commitment to educational resources for the
public and an aquarium willing to take a risk.
A pilot program that used ultraviolet light to combat aquatic
invasive plants has shown promising results. Results from the
program, which was deployed in Lakeside Marina in the summer of
2017, show the use of ultraviolet-C light successfully killed
submerged aquatic plants, according to the Tahoe Resource
The state Department of Fish and Wildlife has been battling the
destructive Nutria for two years. State biologists believe it
will be another three years before they win the war against the
pesky rodent. The nutria is considered a triple threat to
Valley wetlands, agriculture and water delivery systems.
They are a semiaquatic South American rodent a bit smaller than
a beaver. Females can give birth three times a year and have up
to 12 babies each litter. They are really good at tearing up
crops, burrowing tunnels into levees, and other destructive
behavior that is tough on farmers. And they’ve been discovered
in California’s San Joaquin Valley, a major food-producing
What better way to decompress from a stressful federal
government job than by trekking 2,600 miles on foot from Mexico
to Canada? That’s what Jared Blumenfeld, the new head of the
California Environmental Protection Agency, did three years
ago, setting out on the arduous and beloved Pacific Crest Trail
that traces California’s searing deserts, rugged mountains and
One tunnel or two, neither idea adds a drop of the water to
needs of the nearly 40 million people who call California home.
The tunnels simply divert existing water supplies while putting
in severe jeopardy the largest freshwater estuary west of the
Mississippi River, the Sacramento-San Joaquin River Delta that
juts into the western edge of Stockton. Clearly, there must be
better solutions. Three approaches leap to mind: storage,
conservation and desalination.
The California Department of Food and Agriculture, working in
cooperation with the Shasta County Agricultural Commissioner’s
Office, has eradicated two hydrilla infestations within the
cities of Redding and Anderson, ending a quarantine that began
on July 18, 1996. Hydrilla, an invasive aquatic weed, was last
detected in Shasta County in 2006.
Metropolitan General Manager Jeffrey Kightlinger said
… the agency intends to work constructively with the
Newsom administration on developing a WaterFix project “that
addresses the needs of cities, farms and the
environment.” But Kightlinger expressed frustration that
the project will be delayed even more.
Two experts from Stanford’s Water in the West program explain
the potential impacts on the future of water in California of
the proposed plan to downsize the $17 billion Delta twin
tunnels project. … Leon Szeptycki, executive director
of Stanford’s Water in the West program, and Timothy
Quinn, the Landreth Visiting Fellow at Water in the West,
discussed the future of water in California and potential
impacts of a tunnel system.
At long last, the Sacramento-San Joaquin River Delta
twin-tunnels boondoggle is dead. Good riddance. Gov.
Gavin Newsom made that official Tuesday during his State of the
State address, calling instead for a smaller, single-tunnel
approach that would include a broad range of projects designed
to increase the state’s water supply. Bravo. It’s a
refreshing shift from Gov. Jerry Brown’s stubborn insistence
that California spend $19 billion on a project that wouldn’t
add a drop of new water to the state supply.
In a major shift in one of the largest proposed public works
projects in state history, California Gov. Gavin Newsom on
Tuesday announced he does not support former Gov. Jerry Brown’s
$19 billion plan to build two massive tunnels under the
Sacramento-San Joaquin River Delta to make it easier to move
water from the north to the south. “Let me be direct about
where I stand,” Newsom said. “I do not support the twin
tunnels. But we can build on the important work that’s already
been done. That’s why I do support a single tunnel.”
The Humboldt Bay Harbor, Recreation and Conservation District
today approved the lease agreement, which will last 30 years
after an initial 3-year period set aside for vetting and
permitting the company. … But some fishermen and
other county residents voiced skepticism about how closely the
company has been vetted, as well as criticism of the district’s
swift decision to sign onto the lease.
California’s San Joaquin River Delta is in danger of being
overrun by voracious beagle-sized rodents. The state has a plan
to deal with them, but it’s going to take a lot of time and
money. Nutria, a large South American rodent, have become an
invasive species in several states, including Louisiana,
Maryland and Oregon.
Despite many high priority issues on his plate, one of Gov.
Gavin Newsom’s first tests will be how he deals with
California’s water challenges and opportunities. Unfortunately,
in the last days of his term Gov. Jerry Brown made a bad
bargain with the Trump administration and special interests.
It’s yet another mess for the new governor to mop up.
An assortment of groups … joined the legal fray in courts
over the State Water Board decision in December to reduce water
diversions for farms and cities from the Tuolumne, Stanislaus
and Merced rivers. The emotions leading up to the Dec. 12
decision have touched off debate on what exactly could
restore a severely impaired delta estuary and depleted salmon
populations and what it will cost for Central Valley
While campaigning for president in 2016, Donald Trump promised
a cheering Fresno crowd he would be “opening up the
water” for Central Valley farmers… Trump took one of the
most aggressive steps to date to fulfill that promise Tuesday
by proposing to relax environmental regulations governing how
water is shared between fish and human uses throughout the
Details of the Sacramento River portion of the SWRCB’s plan are
still preliminary, but we expect the required water releases to
be higher for the Sacramento River, and its tributaries, than
they are for the San Joaquin River. SWRCB staff is currently
recommending that between 45 and 65 percent of the natural
runoff of northern California rivers be allowed to flow to the
The nutria invasion of California continues. Greg Gerstenberg,
a biologist and nutria operations chief with the California
Department of Fish and Wildlife, said 372 nutria had been
trapped in the state as of Jan. 10. Bruce Blodgett, executive
director of the San Joaquin Farm Bureau Federation, wants
farmers and others who maintain levees to be aware.
The Santa Clara Valley Water District made a grave
miscalculation in suing the State Water Board over
the Bay Delta Water Quality Control Plan. By alienating the
remnants of the environmental community who have supported them
in recent years, they are jeopardizing future projects and
funding measures that will require voter approval.
Water issues are notoriously difficult for California
governors. Just look at former Gov. Jerry Brown’s floundering
tunnels proposal for the Sacramento-San Joaquin River Delta.
Yet two factors suggest that Gov. Gavin Newsom must make water
In an unprecedented move, the Water Resources Control board
voted in December to require water users to leave more water in
the lower San Joaquin River to improve water quality and help
fish. “This decision represents the water board taking its job
to protect the public trust and our fisheries more seriously,”
said Regina Chichizola, salmon and water policy analyst for the
Institute for Fisheries Resources.
A Dallas-based engineering firm is being tapped to help design
California’s plan to bolster its water supply system. Jacobs’
initial $93 million contract is for preliminary and final
engineering design of a 15-year program known as California
WaterFix. The Golden State’s largest water conveyance project
carries a $17 billion pricetag. WaterFix, slated to begin this
year, will upgrade 50-year-old infrastructure dependent on
levees, which the state said puts clean water supplies at
risk from earthquakes and sea-level rise.
Since taking office Jan. 7, Gov. Gavin Newsom has not
indicated how he intends to approach one of the state’s most
pressing issues: water. Newsom should signal that
it’s a new day in California water politics by embracing
a more-sustainable water policy that emphasizes
conservation and creation of vast supplies of renewable
water. The first step should be to announce the
twin-tunnels effort is dead.
Bureau of Reclamation Commissioner Brenda Burman today named
Ernest A. Conant director of the Mid-Pacific Region. Conant has
nearly 40 years of water law experience and previously served
as senior partner of Young Wooldridge, LLP.
The State Water Resources Control Board has proposed flow
requirements for rivers that feed the Delta based on a
percentage of ‘unimpaired flows… If approved, this
‘unimpaired flows’ approach would have significant impacts on
farms, communities throughout California and the environment.
We join many other water agencies in our belief that
alternative measures …
Citing what they say would be a disastrous decision for the
region, the Oakdale and South San Joaquin Irrigation Districts
have joined with other members of the San Joaquin Tributaries
Authority (SJTA) in a lawsuit challenging the state’s right to
arbitrarily increase flows in the Stanislaus and two other
The California Department of Fish and Wildlife (CDFW) today
released the Delta Conservation Framework as a comprehensive
resource and guide for conservation planning in the
Sacramento-San Joaquin Delta through 2050. The framework
provides a template for regional and stakeholder-led approaches
to restoring ecosystem functions to the Delta landscape.
The confluence of California’s two great rivers, the Sacramento
and the San Joaquin, creates the largest estuary on the West
Coast of the Americas. Those of us who live here call it,
simply, the Delta. It is part of my very fiber, and it is
essential to California’s future. That’s why we must save it.
After more than three years, 104 days of testimony, and over
twenty-four thousand pages of hearing transcripts, the hearing
before the State Water Resources Control Board (State Board) on
the proposal to construct two tunnels to convey water under the
Delta (aka California WaterFix) is almost completed.
Probably, that is: there could be more if the project changes
again to a degree that requires additional testimony and/or
In an attempt to block the state’s plan to divert more water
toward the Sacramento-San Joaquin River Delta and away from the
Bay Area, the Santa Clara Valley Water District has filed a
lawsuit arguing the project could significantly reduce the
local water supply. If the plan advances, the water district
might have to spend millions of dollars to obtain alternate
water supplies and pull up more groundwater.
The State Water Resources Control Board proved back on Dec. 12
that it wasn’t listening to a single thing anyone from our
region was saying. By voting to impose draconian and
scientifically unjustifiable water restrictions on our region,
four of the five board members tuned out dozens of scientists,
water professionals and people who live near the rivers.
Mount, a senior fellow at the Water Policy Center at the Public
Policy Institute of California, spoke recently about
managing freshwater systems with ecosystem water budgets. “I
will argue that drought, because of the way we have modified
this system, is the major bottleneck ecologically,” he said.
“Step 1 has to be thinking about drought: how to mitigate
drought and how to deal with drought – that is plan for,
respond to, and recover from drought. We don’t do that at
all, even though we just had this big drought.”
Jon Rosenfield: Last month the State Water Resources Control
Board finally required increased flows from three San Joaquin
River tributaries, as the first step in a process to update
water quality standards for the San Francisco Bay
estuary. The board opted for weaker environmental
protections in order to reduce impacts to agribusiness and San
Francisco, ignoring the potential for changed agricultural
practices and investment in sustainable water use to ease or
eliminate the impact of reduced water diversions.
The growing leadership of women in water. The Colorado River’s persistent drought and efforts to sign off on a plan to avert worse shortfalls of water from the river. And in California’s Central Valley, promising solutions to vexing water resource challenges.
These were among the topics that Western Water news explored in 2018.
We’re already planning a full slate of stories for 2019. You can sign up here to be alerted when new stories are published. In the meantime, take a look at what we dove into in 2018:
In 2014, plant biologists with the California Department of
Agriculture reported an alarming discovery: native wildflowers
and herbs, grown in nurseries and then planted in ecological
restoration sites around California, were infected with
Phytophthora tentaculata, a deadly exotic plant pathogen that
causes root and stem rot. While ecologists have long been wary
of exotic plant pathogens borne on imported ornamental plants,
this was the first time in California that these microorganisms
had been found in native plants used in restoration efforts.
Prompted by the collapse of fish populations, the State Water
Resources Control Board is trying to prevent humans from
totally drying up these rivers each year. The regulators’
lodestar for how much water the rivers need is the amount of
water a Chinook salmon needs to migrate.
The report issued by California’s State Water Resources Control
Board marks a key step in a decade-long effort to remove four
hydroelectric dams and restore the health of the Klamath River.
The dam-removal project is part of a broader effort by
California, Oregon, federal agencies, Klamath Basin tribes,
water users and conservation organizations to revitalize the
basin, advance recovery of fisheries, uphold trust
responsibilities to the tribes, and sustain the region’s
farming and ranching heritage.
Merced County sweet potato farmer Stan Silva hadn’t even heard
the word “nutria” until a few months ago. He’s still never seen
one, but he’s worried about the damage these 20-pound rodents
with big orange buck teeth could do in California if they’re
not eradicated. “It would be devastating,” Silva says. “They
can basically ruin the ag industry here — they get in your
fields, burrow into your canal ways, your waterways.” They can
also tear up crops and levees, making the state’s water
infrastructure more vulnerable.
The U.S. Senate approved a compromise policy Wednesday on
dumping ship ballast water in coastal ports and the Great
Lakes, a practice blamed for spreading invasive species that
damage the environment and the economy. The plan, part of a
$10.6 billion Coast Guard budget authorization bill, includes
provisions sought by environmentalists as well as the cargo
The tiny black dots on the soggy leaf that Emily King plucked
out of Mount Diablo Creek the other day did not look very
threatening, but the UC Berkeley biologist knows well how looks
can be deceiving. King, 25, has spent the past year and a half
studying the smaller-than-tick-size specks, a dreaded sight for
researchers familiar with what an infestation of New Zealand
mud snails looks like.
The California Department of Fish and Wildlife hit a milestone
in its ongoing efforts to control the state’s nutria
infestation on Friday morning when they successfully trapped
Nutria number 300 at a pond in Merced County. … The
department is currently expanding its operations in San Joaquin
County, and is concerned by several reports of nutria on the
doorstep of the Sacramento–San Joaquin River Delta, a critical
region for California’s agricultural infrastructure.
Having been hauled thousands of miles from across the country,
a pontoon boat bound for a weekend on Lake Tahoe pulls into the
Alpine Meadows Watercraft Inspection Station. It’s one of
roughly 8,000 motorized vessels that were inspected during this
past boating season, and one of more than 5,000 that did not
meet Lake Tahoe’s Water Inspection Program’s standards of being
clean, drained and dry.
For years, state boats have sprayed thousands of pounds of
herbicides into the Sacramento-San Joaquin Delta to kill
invasive aquatic weeds. And, for years, California officials
have insisted they closely monitor their chemical use to
protect the ecologically fragile estuary and the drinking and
irrigation water the Delta supplies to millions of
Californians. A pending court case casts fresh doubt on those
The intense drought in the Southwest is threatening
Colorado water supplies beyond just the lack of rainfall. State
wildlife officials report a record number of boats carrying
invasive mussels coming into Colorado from out of state. And
the arid summer and winter could be to blame.
Blindly feeling along a section of fabric mat underneath the
water’s surface at Lakeside Marina, a diver grabs a U-shaped
piece of rebar and begins hammering away. At only a handful of
feet below the water’s surface visibility drops to zero, making
work difficult, but it’s an essential job in what could be a
vital piece in the puzzle to solve Lake Tahoe’s aquatic
invasive species problem.
Wading into the water along the rocky shore off Aramburu Island
in Richardson Bay, Brian Cheng reached 3 feet under water and
pulled up an algae-covered rock. “Here we go,” he yelled as he
splashed ashore soaking wet and pointed out a tiny snail on the
underside of the rock. “And, we got a bonus,” he said,
gesturing toward a cluster of yellow gelatinous egg capsules.
Since 2010, Boating and Waterways has put more than 14,000
gallons of Roundup into the Delta, according to a McClatchy
review of data provided by the agency. The Roundup
treatments are part of a concerted effort to kill nonnative
aquatic plants, which have become so pervasive in the Delta
that NASA scientists can see them from space.
An 8-year-old chocolate Labrador named Popeye is patrolling
Lake Nacimiento this weekend, using his sensitive sniffer to
protect the reservoir from a dangerous invader. He and his
friends — Nemo, Captain, Noah and Sinbad — are the Mussel Dogs,
a group of Labs, a mutt and a German Shepard specially trained
to inspect boats for invasive species and protect California’s
waterways from quagga and zebra mussels.
Nearly three months ago, a Delta farmer from Roberts Island
delivered the carcass of a dead nutria to the desk of Tim
Pelican, San Joaquin County’s agricultural commissioner. It was
the first of two nutria discovered in the county in April.
An invading army of moths is stripping the leaves from aspen
trees around Lake Tahoe, and state officials are seeking the
public’s help to document the problem. White satin moths are a
non-native defoliator of aspens, cottonwoods, willows and other
Sixty percent of California’s developed water supply
originates high in the Sierra Nevada mountains. Our water
supply is largely dependent on the health of our Sierra forests,
which are suffering from ecosystem degradation, drought,
wildfires and widespread tree mortality.
We headed into the foothills and the mountains to examine
water issues that happen upstream but have dramatic impacts
downstream and throughout the state.
GEI (Tour Starting Point)
2868 Prospect Park Dr.
Rancho Cordova, CA 95670.
DNA analysis confirmed this week that stowaway shellfish
intercepted at the Lake Mendocino boat ramp early this month
were invasive quagga mussels, as initially feared. The finding
by state Fish and Wildlife personnel validates just how close
the region came to confronting a destructive scourge.
For more than 100 years, invasive species have made the
Sacramento-San Joaquin Delta their home, disrupting the
ecosystem and costing millions of dollars annually in
remediation. The latest invader is the nutria, a large rodent
native to South America that causes concern because of its
propensity to devour every bit of vegetation in sight and
destabilize levees by burrowing into them. Wildlife officials
are trapping the animal and trying to learn the extent of its
A specially trained dog named Noah is receiving well-deserved
praise after preventing a mussel-infested watercraft from
launching Saturday in Lake Mendocino — a frighteningly close
call that public officials say underscores the need for
long-delayed, full-time measures to protect regional reservoirs
and critical infrastructure from exposure to the destructive
For more than 100 years, invasive
species have made the Sacramento-San Joaquin Delta their home,
disrupting the ecosystem and costing millions of dollars annually
The latest invader is the nutria, a large rodent native to South
America that causes concern because of its propensity to devour
every bit of vegetation in sight and destabilize levees by
burrowing into them. Wildlife officials are trapping the animal
and trying to learn the extent of its infestation.
For more than 100 years, invasive species have made the
Sacramento-San Joaquin Delta their home, disrupting the
ecosystem and costing millions of dollars annually in
remediation. … Even though invasive plants and animals long
have been known to exist in California’ water hub, tracking
their extent in an area as large as the Delta — 738,000 acres —
is an uneven task that could benefit from greater coordination
and funding, a panel of experts recently told the Delta
Independent Science Board.
Lake Tahoe continues to be a test site for new technology aimed
at controlling aquatic invasive plants. The latest example is
the use of a device called a “bubble curtain” in the Tahoe Keys
neighborhood, according to the League to Save Lake Tahoe, which
is working with the Tahoe Keys Property Owners Association to
combat invasive plants that have overrun the channels in the
We traveled deep into California’s
water hub and traverse 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. The tour made its way to San Francisco Bay,
and included a ferry ride.
Before the midday heat had set in, Jeff Cann and Tim Kroeker
were out of their Dodge pickup, trudging through waist-deep
water in waders and rubber boots. The two wildlife biologists
had come to this vast expanse of sun-soaked Central Valley
wetlands on a recent morning to check in on the first traps
that California has authorized in its nascent effort to hunt —
and exterminate — the nutria.
The organism, responsible for the catastrophic decline of the
Sierra Nevada yellow-legged frog and 200 other species, emerged
from East Asia in the early 1900s and is spreading by the pet
trade and the expansion of global trade, according to an
international research consortium of 38 different institutions.
The U.S. Army Corps of Engineers has reached an agreement with
the Tahoe Regional Planning Agency to provide $1 million in
federal funding to help combat invasive aquatic species that
harm the health and clarity of Lake Tahoe.
The “triple threat” of invasive rodent species has made its way
to the edge of the delta, officials said, putting the state’s
fragile water infrastructure at risk. The California Department
of Fish and Wildlife said Tuesday that it had discovered the
nutria, a large rat-like mammal that inhabits wet, rural areas,
on agricultural land west of Stockton.
The destructive invasive swamp rodents known as nutria are
officially on the doorstep of one of the state’s most
critically important waterways. State wildlife officials
announced Tuesday that a nutria was killed on agricultural land
west of Stockton in San Joaquin County.
About the size of a beagle, they can quickly turn a lush green
marsh to a wasteland. … They are called nutria, and right now
they’re starting to spread through the waterways leading into
the Sacramento-San Joaquin Delta, the ecologically fragile
network of sloughs and rivers that functions as the heart of
California’s flood-control and water distribution system.
Last winter’s drought-busting wet weather was a boon for
reservoirs and parched landscapes, but not so much for some
invasive species in San Francisco Bay, according to a long-term
study by Tiburon-based researchers. All that fresh water
that poured into the bay was bad news for certain invaders,
which have turned up in droves in recent decades from around
the world, often in ships’ ballast water.
Tahoe Resource Conservation District is three years into a
long-term aquatic invasive species eradication project on the
Truckee River — and the progress is encouraging. TRCD is
working to eliminate Eurasian watermilfoil from a 3-mile
stretch of the Truckee River, starting above the Tahoe City dam
and continuing down to Alpine Meadows Road.
This tour traveled deep into California’s water hub and traversed
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. The
tour made its way to San Francisco Bay and
included a ferry ride.
Governors of 19 Western states are pressing the federal
government to do more to prevent the spread of damage-causing
invasive mussels from infected federally managed waterways.
… The governors say they’re particularly concerned about
the mussels reaching the Columbia River Basin, Lake Tahoe, and
the Colorado River Basin above Lake Powell.
For months, regional water officials were prevented from
recharging drought-depleted water basins in the San Gabriel
Valley and southeast Los Angeles County because they feared an
infestation of an invasive shellfish that could destroy local
Like a scene in a horror movie where the evil creature keeps
coming back, invasive green crabs in the Seadrift Lagoon at
Stinson Beach just won’t seem to die. … Green crabs are
native to Europe and were introduced in the early 1800s to the
East Coast of the United States, and finally made their way to
San Francisco Bay in the late 1980s, possibly via ballast water
There’s an invasion plaguing the coastal waters of Southern
California. Waves of tiny interlopers spark havoc at fisheries,
clog municipal water pipes and frustrate boaters who must
dislodge buckets of sea crud.
Estuaries are places where fresh and
salt water mix, usually at the point where a river enters the
ocean. They are the meeting point between riverine environments
and the sea, with a combination of tides, waves, salinity, fresh
water flow and sediment. The constant churning means there are
elevated levels of nutrients, making estuaries highly productive