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
then multiply.
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.
A new California law will allow hunters to kill nonnative
swans. Gov. Gavin Newsom signed the bill, Assembly Bill 764,
into law on Tuesday. The bill adds mute swans — the iconic
white swan brought to the United States to decorate parks and
estates — to the list of invasive birds that can be hunted with
few restrictions. … They’ve spread to lakes and
reservoirs across Northern California; however, [UC Davis
Museum of Wildlife and Fish Biology curator Andrew] Engilis
said they especially enjoy the open water in the
Sacramento-San Joaquin Delta, where
researchers have observed flocks as large as 400 birds.
… Every few years, wild pigs emerge from river habitat to
wreak havoc in the Fairmount Park area. … The pigs currently
roaming Riverside’s corridors descend from domestic swine that
escaped during catastrophic 1930s floods. … The Santa
Ana River corridor creates a green highway connecting
rural habitats to urban resources, with residential
neighborhoods serving as unintended waypoints between
wilderness areas. … The pigs have inhabited these river
bottoms longer than most human families, and they’ll probably
outlast current management strategies too.
The California Department of Water Resources is implementing
new safety measures after the discovery of invasive golden
mussels in Merced County. The California Department of Water
Resources (DWR), in collaboration with the California
Department of Fish and Wildlife (CDFW) and California State
Parks, is implementing new measures to protect the state’s
water infrastructure and curb the spread of invasive golden
mussels. This follows the recent discovery of the species at
San Luis Reservoir in Merced County, with confirmed findings in
Fresno and Kings Counties.
… [T]here’s only about 3,000 sea otters in California. The
playful predators’ voracious appetite for destructive species
like green crabs and purple urchins has transformed
Elkhorn Slough, the state’s second-largest
estuary, into an aquatic Serengeti and makes the
central coast’s carbon-sequestering kelp forests more resistant
to climate change. … The US government determined in
2022 that reintroducing sea otters on California’s North Coast
and Oregon would be a boon to biodiversity and climate
resilience. … But as the Trump administration moves to slash
funding for wildlife programs, a nonprofit co-founded by a
Silicon Valley entrepreneur is stepping in.
A new abatement project is underway in Madera County to help
reduce flood and wildfire risks while improving local water
supplies. The project targets Arundo donax, an invasive weed
that can grow up to four inches per day and reach 30 feet in
height. Highly flammable, the plant clogs waterways and can
cause floodwaters to overtop levees and other infrastructure,
posing a threat to public and private property. Last month,
crews completed a detailed, non-invasive drone mapping process
to identify key areas for removal.
After 35 years of working in organic pest control, serial
entrepreneur Pam Marrone is on a new mission to eradicate
invasive species using alternatives to terrible chemicals. In
particular, she’s on a quest for what she calls “the holy
grail” – an eco-friendly herbicide that will zap out non-native
weeds. “We have the team that can really execute it,” says
Marrone, whose 2-year-old startup, Invasive Species Corp.,
known as ISC, is already helping the state of California find a
sustainable way to deal with golden mussels,
which clog waterways and damage water treatment facilities.
“There’s nobody doing exactly what we’re doing with invasive
species.”
Five individuals have been caught illegally mining along
several California waterways, state officials
announced. According to a Sept. 26 news
release from the California Department of Fish and
Wildlife, the citations began in August of last year, when
authorities found someone operating a suction dredge — a
powerful tool that sucks materials out of underwater cracks and
crevices — on the Salmon River. … According to the CDFW,
this motorized equipment can harm fish and their native habitat
by releasing contaminants, causing erosion and potentially
creating more favorable conditions for the invasive signal
crayfish.
Officials at Pyramid Lake say starting Oct. 1, watercraft
inspections will become mandatory for any craft using the lake.
The new regulation was approved by the Pyramid Lake Paiute
Tribal Council to strengthen protections against the invasive
mussels already seen in the Lake Tahoe area. The council says
the adaptability of the Golden Mussels makes them a serious
threat to the lake and its surrounding bodies of water.
Starting Oct. 1, all motorized and/or trailered watercraft must
be inspected prior to launch at the lake.
Now that Colorado’s zebra mussel problem has been confirmed in
the Colorado River, the strategy for fighting
the invasion has started to shift. Colorado Parks and Wildlife
said it won’t try chemical treatments on the river as they’ve
done in the past with Highline Lake, one of the first spots CPW
found the mussels. It believes the risks that could bring to
native fish, along with the sheer scale of the waterway make
that impossible. Instead, the focus now is on containing the
spread and keeping mussels out of other lakes and reservoirs.
In a startling development for California’s water system, state
officials have confirmed the infestation of invasive golden
mussels (Limnoperna fortunei) at two major Southern California
lakes: Silverwood Lake in San Bernardino County and Pyramid
Lake in Los Angeles County. The rapid spread of this highly
destructive species from the Sacramento-San Joaquin Delta to
the southern reaches of the State Water Project marks a new
chapter in the state’s ongoing struggle to safeguard both water
infrastructure and delicate aquatic ecosystems. The golden
mussel is notorious worldwide for its ability to multiply
quickly, clog pipes and screens, destabilize local ecology, and
create costly headaches for urban, agricultural, and
recreational water systems.
… The invasive golden mussel has been confirmed at
Silverwood Lake in San Bernardino County and Pyramid Lake in
Los Angeles County, according to the Department of Water
Resources, the California Department of Fish and Wildlife and
California State Parks. The two lakes are now the southernmost
reservoirs in the State Water Project where the mussels have
been found. … The mollusk’s fast march across California
could spell trouble for the state’s vast network of canals,
reservoirs and pipelines, which shuttle water from the San
Joaquin Delta to other parts of the state.
Adult zebra mussels have been found in the Colorado River and a
nearby lake in Grand Junction, Colorado Parks and Wildlife said
Monday. The agency has detected the invasive species in
its larval stage, called a veliger, in past sampling efforts in
the river and nearby lakes. This is the first time an adult
zebra mussel, a sign of a more established population, has been
found in the Colorado River in Colorado. … They can take
up key nutrients for other aquatic species — tanking food
systems — and can build up in layers on docks, pipes and
diversion headgates, ruining water infrastructure.
The Department of Water Resources (DWR), California Department
of Fish and Wildlife (CDFW), and California State
Parks have confirmed presence of the invasive golden
mussel at Pyramid Lake in Los Angeles County
and Silverwood Lake in San Bernardino County. These lakes
are the southernmost State Water Project (SWP) reservoirs
where golden mussels have been detected. The invasive
species was recently discovered during a routine water test by
DWR; in response, State Parks has updated Silverwood
Lake’s boat inspection protocols, effective immediately.
Invasive golden mussels may have been spotted in Butte County
last week, raising concerns about the potential impact on local
water resources. A recent watercraft inspection at the
Thermalito North Forebay prevented what is suspected to be the
invasive species from entering the water, marking only the
second time they have been seen at the site. … The
Oroville facilities, including the Thermalito Forebay,
Thermalito Afterbay, and Lake Oroville, supply water to roughly
23 million Californians.
Wild pigs roam on the loose in 56 of California’s 58
counties. … [E]specially in warm weather, pigs love to hang
out in streams and ponds. “They’ll wallow in the water
sources, which is one of the types of damage they do,”
[Santa Clara Valley Open Space Authority Natural Resource
Technician David] Mauk said. “[It] harms the sides of banks,
causes a lot of erosion, damages the vegetation in those
riparian areas and really destroys the habitat for other
animals that want to use those, like the California red-legged
frog.”
Water is a driving force in the American West, and today it’s
at risk more than ever. Not just from overuse, not just from
megadrought, but from minuscule invaders that pose a nearly
unstoppable threat to the region’s rivers, lakes, dams and
reservoirs. …The mollusks’ westward sweep recently crossed a
feared Rubicon when Colorado discovered zebra mussels in its
portion of the Colorado River system, an imperiled lifeline to
40 million people.
Golden mussels pose a growing threat to California’s waterways
and infrastructure. … Dr. Pam Marrone is the co-founder of
the Invasive Species Corporation, a Davis-based company seeking
to find environmentally-friendly solutions to control invasive
species. The company created a product called Zequanox that
successfully eradicates non-native zebra and quagga mussels,
and is now adapting that product for the newest aquatic
invader. Marrone spoke with Insight Host Vicki Gonzalez about
her experience in biocontrol, and her company’s work to get rid
of the golden mussel for good.
A new aquatic invader, the golden mussel, has penetrated California’s ecologically fragile Sacramento-San Joaquin Delta, the West Coast’s largest tidal estuary and the hub of the state’s vast water export system. While state officials say they’re working to keep this latest invasive species in check, they concede it may be a nearly impossible task: The golden mussel is in the Golden State to stay – and it is likely to spread.
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.
Nutria are large, beaver-like
rodents native to South America that have caused alarm in
California since their rediscovery along Central Valley rivers
and other waterways in 2017.
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:
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.
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 infestation.
Estuaries are places where fresh and
salt water mix, usually at the point where a river enters the
ocean. They form highly productive natural habitats due to a
combination of tides, waves, salinity, fresh water flow and
sediment.
A troublesome invasive species is
the quagga mussel, a tiny freshwater mollusk that attaches itself
to water utility infrastructure and reproduces at a rapid rate,
causing damage to pipes and pumps.
First found in the Great Lakes in 1988 (dumped with ballast water
from overseas ships), the quagga mussel along with the zebra
mussel are native to the rivers and lakes of eastern Europe and
western Asia, including the Black, Caspian and Azov Seas and the
Dneiper River drainage of Ukraine and Ponto-Caspian
Sea.
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.
