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.
Government-sanctioned tests of equipment designed to cleanse
ship ballast water of invasive species are seriously flawed
because they don’t determine whether the systems will remove
microbes that cause gastrointestinal illnesses, scientists said
Wednesday.
Goodness gracious, politicians and state officials are abuzz
these days about the water hyacinth problem in the Delta waters
around Stockton. … Which begs the questions: Where was this
fervent reaction in 2013? And 2012? And 2011? And 2010?
Recent storms have mostly cleared Stockton waterways that were
hijacked by hyacinth the past two months, but officials at a
standing-room-only town hall meeting Monday said it’s important
to stay focused on the future.
The lake of [Jay] Hall’s memory is dead, its salmon all but
vanished in the past decade – a collapse so swift that
fisheries biologists have likened it to driving off a cliff.
For a brief few decades, those biologists had turned this Great
Lake into a Pacific chinook factory, taking a wildly popular
sport fish from faraway ocean waters and setting it loose to
gorge upon the swarms of invasive alewives that had decimated
native fish species.
The earthquake and tsunami that devastated a large part of
Japan almost four years ago is still causing trouble, not only
for Japan, of course, but also for the Northwest coastline. The
biggest threat isn’t radioactive particles from the Fukushima
power plant meltdown, though some has recently shown up on this
side of the Pacific, but potential invasive species hitching a
ride on debris that’s been out in the ocean these few years.
State officials said the weather is playing a role in ridding
the delta of a stubborn water weed that has plagued Stockton’s
Waterfront, but added that the state is also upping its efforts
to finish off the pesky plant.
The Village West Marina in Stockton recently came up with a
possible solution to help weed out the growing water hyacinth
problem, but the San Joaquin County Sheriff’s Department put an
end to the plans for now, saying it breaks a harbor navigation
code.
Don’t expect those water weeds to vanish tomorrow, but state
and federal support seems to be growing for a long-term
strategy to wage war against hyacinth.
Water hyacinth is clogging Delta waterways in a spurt of
uncontrolled growth this year. A task force is looking for
solutions to nip the weed in the bud in the spring.
The end came quickly Wednesday for the invasive fish that had
turned San Francisco’s historic Mountain Lake into a mucky
swamp-like pond filled with gluttonous aliens.
Poison will be pumped into Mountain Lake early Wednesday
sending the last remaining invasive fish into death throes and
clearing the way for ecosystem restoration.
The third time was not the charm for backers of a Lake County
sales tax measure aimed at raising $24 million over 10 years to
combat algae blooms in Clear Lake and protect it from invasive
mussels.
Tangled mats of water hyacinth delayed the arrival of an
oceangoing ship at the Port of Stockton on Tuesday, further
evidence that the exotic weed has potential to threaten
business and commerce.
To John Laird, Secretary of the California Natural Resources
Agency: The hyacinth situation in parts of the California Delta
has become a disaster. The navigable part of the Calaveras
River is completely filled in with the pest as are Buckley
Cove, downtown Stockton harbor, Whiskey Slough, much of the San
Joaquin River and many other areas — this is just a sampling.
With Stockton’s water hyacinth invasion seeming to only get
worse, San Joaquin County legislators on Friday asked state
officials to request a “sustained funding source” from the
federal government to fight back against the prolific weeds.
The Bureau of Reclamation has released a report summarizing six
years of testing coatings to control the attachment of quagga
and zebra mussels to water and power facilities. … The
testing was conducted at Parker Dam on the Colorado
River.
In a final effort to rid thousands of invasive fish from the
Presidio’s historic Mountain Lake and make room for native
species, biologists will use a standard fish-killing chemical
called rotenone, park officials said this week.
A project to suffocate Asian clams at Lake Tahoe’s treasured
Emerald Bay may be coming to an end this month, when divers
help remove about 5 acres of rubber matting being used to cut
off the species’ oxygen supply.
Asian Citrus Psyllids, an invasive insect, have been found in
Manteca and Lodi, according to San Joaquin County Agricultural
Commissioner Tim Pelican. … The psyllids pose no threat to
humans, but they can carry the huanglongbing disease, also
known as citrus greening.
For the second year in a row, despite state officials’ efforts
to control water hyacinth with herbicides as early as March,
another bumper crop is now making its annual fall push into
Stockton and other portions of the Delta.
Invasive species are both a fact of life and a scientific
puzzle. … Many of those species die off in their new homes.
Some barely eke out an existence. But some become ecological
nightmares.
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.
