 The
Tomales Bay Biodiversity Partnership is developing an Early
Warning System to identify threats to bay health by non-native
species. Through regular survey work, a team of scientists
from area Universities, the National Park Service, and California
State agencies will identify the presence of non-native species
and develop control and eradication strategies. By locating
the presence of invasive species before they are able to spread,
the TBBP's Early Warning System will prevent or slow alteration
of the ecosystem.
Bulletin: Click
here to learn more about Didemnum lahillei, an
invasive tunicate first located in Tomales Bay in 2003.
The
Importance of Tomales Bay
 Tomales Bay is an important source
of seafood, a cherished environ of recreation, and a
living laboratory where
the
lessons of biodiversity may improve our health and
sustainability. Herring is harvested from Tomales
Bay, and its waters
are important rearing areas for threatened Steelhead
and Coho Salmon. Changes in the bay’s biological
community structure would alter the viability of
these important
species.
The invasion of non-native species
changes food webs. Invasions can also have landscape effects,
affecting shorelines and navigation. With the degradation
of Tomales Bay's biological diversity and the loss of native
species, we also lose the lessons we can learn from healthy
ecosystems. Every species represents a different life strategy,
some degree of success in the process of adaptation. Each
is likely to possess unique traits from which we could develop
medical applications, improve engineering, increase our longevity,
or improve the sustainability of food production. Human systems
can learn from the methods marine organisms have developed
over the eons to solve practical questions. Learning the life
strategies of marine organisms may also help us answer questions
we have not yet thought to ask.
How
Invasives Spread
 Every day, species are being moved around the world by
human activity. The primary means by which invasive species
have reached the waters of the Pacific coast is via shipping
transport. Cargo ships take on and release ballast water
in order to adjust their stability in various stages of
a journey. Sometimes water taken up is released thousands
of miles from its origin, releasing any organisms that
may have come along for the ride. Additionally, species
are transported intentionally through the pet and exotic
species trades. Species escape into the wild inadvertently
when people wash an aquarium or more intentionally when
an aquarium is emptied into a stream or bay. Occasionally,
owners no longer desiring an animal once regarded as either
a pet or rare prize release an animal outside. In the
absence of natural predators, an animal once thought of
as charming or beautiful may become an ecological nuisance.
Also, plants used as ornamentation may release their seeds
into surrounding areas and alter the ecosystem. Additionally,
species spread through trade in foods. Edible seaweeds
popular in Asian cuisine have already become established
along the American coast, one of which (Wakame) has begun
to crowd out native species in the areas it has invaded.
Organisms also reach new locations when people release
live bait or are introduced intentionally for erosion
control, improving sport fish stock, and landscaping.
Invasives may reach new locations through wastewater disposal,
within discarded packaging, or via aquaculture tools and
materials transport.
The
Consequences of Species Invasions
 Invasive
species may do more than overtake native species habitat and
disrupt the balance of an ecosystem's predator-prey relationships.
They may carry pathogens or parasites, have a fouling effect
on water quality or clog waterways. Others, such as Cordgrass
growing in dense clusters, can alter water flow, reduce erosion
and over time change mudflats into meadows. Such changes can
alter the suitability of a habitat for migratory and nesting
birds, spawning fish and numerous invertebrates.
Asian
Invaders
 Though 6000 miles of open ocean separate the California
coast from mainland Asia, human activity creates biologcial
exchange between the regions. Numerous species have already
crossed the oceans by hitching a ride on ships and planes.
However, with improved transportation systems, ecological
study, and active coastal stewardship, the effects of
these invasions and the preventions of future invasions
can help the survival of native species. There are many
overland routes invasives species may take. Species have
been spread by people hoping for better sport fisheries,
through transport of food products, and by introducing
non-natives in landscaping.
Click here
for short profiles of a few species that may invade the Tomales
Bay.
Click here
for a list of some organisms that have already invaded California.
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