Missouri Department of Conservation
ANS Frequently Asked Questions in Missouri
are aquatic nuisance species (ANS)?
Aquatic nuisance species are non-native organisms
which threaten the diversity of native plants and
animals or the ecological stability of infected waters.
They may also impact human health, and lead to negative
impacts on agriculture, aquaculture, and the recreational
use of Missouri
are aquatic nuisance species a problem? Introducing
plants and animals to new habitats is risky. Free
from natural predators and competitors, some non-native
species reproduce rapidly in their new homes, out-compete
native species (leading to their decline or extinction)
and become a costly nuisance. In general, invasive
species are considered “biological pollutants” that
have led to a severe loss of biodiversity and habitat
alteration throughout the world.
many aquatic nuisance species have entered Missouri
(34) non-native aquatic species of plants and animals
have established populations in Missouri
and 14 have been classed as
aquatic nuisance species.
all non-native species considered a nuisance? No.
Some non-native species are ecologically harmless.
do non-native species get into Missouri
exotic species have been transported from European
ports in the ballast tanks of ocean-going freighters
and are later released into the Great
Lakes . These species eventually
spread throughout the Great
Lakes , down the Illinois
River , and into the Mississippi
River . From the Mississippi
River they can gain access
to many Missouri
streams. Other introductions result from aquarium
releases, escapes from aquaculture facilities, or
left-over bait dumped into a lake or stream. Some
species, such as zebra mussels, can be transported
from one stream or lake to another on boats and trailers,
in live-wells and boat motors, and in bait buckets
are invasive plants a problem? Invasive
plants such as purple loosestrife and Eurasian watermilfoil
are aggressive plants that establish themselves quickly
in wetlands and inland lakes and out-compete and replace
native vegetation. They provide little food or habitat
for wildlife, crowd-out plants that are valuable to
wildlife, form a dense growth that can block access
to the water, or hinder activities such as boating
are scientists doing to control aquatic nuisance species?
across the country, such as fish and wildlife agencies,
Sea Grant, U.S.G.S, and others, support research and
provide information about aquatic nuisance species.
Research is being conducted to develop control measures
for certain aquatic nuisance species.
can I do to help? Learn
to recognize aquatic nuisance species. By becoming
familiar with native and non-native species citizens
can help scientists monitor invasive species populations
and slow their spread. You can also learn how to inspect
your boat, motor, trailer, and other fishing and boating
equipment, to detect the presence of non-native species.
Please dispose of unused bait into the trash after
first placing species that can crawl out (such as
crayfish and worms) into a sealed container. Also,
don't transport bait collected from one lake or stream
to another. Following these general guidelines will
help you avoid transporting non-native species to
new locations. Once you become knowledgeable about
aquatic nuisance species, you can inform your fishing
and boating friends about aquatic nuisance species
so that they can also become part of the solution.
and when can I prevent the spread of aquatic nuisance
species into the waters where I recreate? By
following the simple procedures described below each
time you leave the water, you can help stop aquatic
- Remove any visible
mud, plants, fish or animals before transporting
- Eliminate water from
equipment before transporting.
- Clean and dry anything
that came in contact with water (Boats, trailers,
equipment, clothing, dogs, etc.).
- Never release plants,
fish, or other animals into a body of water unless
they came out of that body of water.
should I use this procedure to prevent nuisance species?
Because aquatic nuisance
- reduce game fish populations,
- ruin boat engines
and jam steering equipment,
- render lakes and rivers
unusable by boaters and swimmers,
- dramatically increase
the operating costs of drinking water plants, power
plants, dam maintenance, and industrial processes,
- reduce or eliminate
native species and degrade ecosystems, and
- diminish human health,
reduce property values, and negatively impact the
economies of communities which depend on the water.
I only fish in a certain lake, do I need to follow
these general procedures? The
one procedure you'll want to be sure to follow is
to not introduce anything into that lake. Therefore,
don't bring your aquarium from home and dump the contents
into the water. Don't accept a fish from another lake
(even if it is a big one) to release in your lake.
If you borrow someone's equipment, clean it before
using in your lake.
also want to inform others about cleaning their equipment
before they come to your lake. You might consider
working with local authorities to put up signs to
that effect around the lake or at public access points
you decide to explore other waters, clean all your
equipment before you go, and again, when you return.
my boat has been in infested waters, do I need to
do anything more than general procedures? The
longer a boat sits in infested waters, the greater
the chance a hitchhiker can attach to your boat, motor,
bumpers, live wells, anchors, etc. If you feel a rough
surface on the bottom of the boat, propeller, or other
items, be sure to clean your boat and equipment using
the procedure for boaters under the “Prevention Section”
above or click here: http://www.protectyourwaters.net/prevention/user_boaters.php
I have to know which aquatic nuisance species are
in which lake or river? Not
if you follow the recommended procedure every time
you leave a body of water. Even if a lake is considered
pristine, you never know when an ANS has been introduced,
but not yet discovered. So, if you get in the habit
of following ANS safety procedures, you'll help protect
is helpful to learn about ANS which are common to
your area. However, you don't have to know which ANS
are in any given lake or stream – as long as you always
follow the procedure.
do I find out more about aquatic nuisance species
(ANS) which have already invaded Missouri
which are future threats? Click
on the Missouri Nuisance Species – Where are they
section of this site. Contact any Missouri Department
of Conservation office in your area, or visit the
Department's web site at http://www.conservation.state.mo.us/nathis/exotic/
. You might also visit Sea Grant at http://www.sgnis.org/
on the internet to learn about the specific nuisance
species that have already invaded and those which
are potentially capable of invasion.
do I contact if I find an animal or plant which may
be an ANS? Email MDC Biologist
Mike Kruse at Mike.Kruse@mdc.mo.gov
did zebra mussels come from? Zebra mussels
are native to the Caspian, Black and Aral Sea regions
of Eastern Europe and Western Asia . Zebra mussels
were likely introduced into the Great Lakes by ships
dumping ballast water from Russian or European ports.
do I know if it's a zebra mussel? Adult zebra
mussels are small, yellowish or brownish, typically
¼ to 1 ½ inches long, with a triangular
or “D” shape with light and dark colored stripes.
They attach by means of byssal threads - hairy thread-like
secretions on the underside of their shells. This
is the only mussel or clam in Missouri that
attaches to the surface of an object. Zebra mussels
detach themselves prior to moving, and, usually, before
were zebra mussels discovered in Missouri
? Zebra mussels were first
discovered in Michigan in 1988 and first documented
in Missouri in 1991 in the Mississippi River .
have they been found in Missouri
since 1991? Since 1991,
we have been very fortunate that only a few sightings
outside the Mississippi River have occurred. In 1999
a single adult zebra mussel was found attached to
a native mussel in the Meramec River not far from
where it joins the Mississippi River near St. Louis
. In 2001 seven dead shells were found on an intake
screen at a power plant on the Missouri River near
Kansas City . It is likely that the zebra mussel can
now be found throughout all of our Missouri and Mississippi
they likely to establish and spread in Missouri
? We hope not, but the fact
remains that they are well established in the Mississippi
and Missouri rivers. In turn, almost all of our inland
streams and rivers are ultimately connected to them.
Barges and unknown numbers of recreational boaters
coming into Missouri waters from zebra mussel infested
waters of the Missouri and Mississippi rivers (or
other out-of-state waters) are a threat to spread
this ANS throughout Missouri . Alert marina operators
have prevented several infested boats from entering
Lake of the Ozarks . Know how zebra mussels can spread
and how to inspect for them.
are zebra mussels such a problem? Zebra mussels
can attach to any hard surface and can potentially
form dense colonies rather quickly. Every year zebra
mussels cost power companies, municipal water supply
companies, and other industries millions of dollars
to routinely clear intake pipes and screens. This
cost is passed on to consumers. Zebra mussels can
affect boaters by clogging cooling systems in motors
which causes them to overheat, and by encrusting boat
and barge hulls which impacts boat performance and
damages the “finish.” These unwanted creatures can
also dramatically impact our native aquatic animals,
such as mussels and crayfish, by directly attaching
in numbers sufficient to impair breathing, feeding
and movement by the victims. Additionally, zebra mussels
can trigger a decline in sport fisheries by filtering
too much organic material from the water which affects
the whole food chain. Many public beaches on lakes
with zebra mussels become smelly, undesirable places
with sharp shells littering the sand after periodic
die-offs of zebra mussels.
can be done to get rid of zebra mussels? At
present, getting rid of zebra mussels seems to be
a near impossible task. They persist at some low level
in all of the waters they've ever invaded, even after
die-offs. There are no safe large scale chemical controls,
and, though there are some natural predators, none
are effective enough to eliminate zebra mussels from
a water body.
can be done to prevent zebra mussels from invading
additional lakes and streams? Currently,
the only way that zebra mussels can be prevented from
expanding their range is for every angler and boater
to take appropriate preventive measures. For this
to work, we must do a better job educating the public
about their threats. Everyone needs to be aware that
they're already found in the Missouri and Mississippi
rivers and are threatening our other precious in-state
waters. For control methods please click here http://www.conservation.state.mo.us/nathis/exotic/zebra/
do zebra mussels spread? Zebra mussels can
spread either by the transfer of either the larvae
(called veligers) or adults. The adults can “hitchhike”
by attaching to boat hulls or vegetation stuck on
boat trailers. Zebra mussel veligers, a free-swimming
microscopic stage, can be transferred in bait bucket
water, a boat's bilge water or motor cooling system
water. Anything that can carry adults or larvae, even
wet clothing, is a potential hazard.
do I do if I find a zebra mussel? Make note
of the date and exact location, put the specimens
in a container with rubbing alcohol and contact your
nearest Missouri Department of Conservation office
(or representative), or call 573-882-9880.