|
|
|
| A
species that reaches its location without assistance from
humans.* |
| a
plant that been introduced to an environment beyond its original
geographic range |
A
non-native species that is capable of moving into a habitat
and monopolizing resources such as light, nutrients, water,
and space to the detriment of other species. *
* New England Wildflower Society |
An ecological community together with its environment, functioning as a unit
of interrelated organisms.
|
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
|
Invasive Species In
and Around
Lake Champlain |
|
Part of the mission of the Lake Champlain
Land Trust is to save the lake's natural communities
by permanently preserving significant islands, shoreline
areas, and adjacent lands. We are particularly sensitive
to the protection of endangered species habitat. Saving
natural communities involves protecting them from invasive
plants and animals that can quickly displace native and
endangered species. Invasive species are most prevalent
on disturbed tracts of land and lake. Protecting sections
of the lake helps to check the
spread of these opportunistic species.
|
|
|
| |
| If you have any questions about
Invasive Species that were not answered
here, please feel free to
email your question
to us at: I
have an Invasive Species question. (info@lclt.org).
We will be happy to try to answer your question or direct you
to a resource.
|
What is an Invasive Species?
People
have been moving plants, intentionally or accidentally, from
one habitat to another over the course of human history.
In most cases, introduced or exotic species are not a threat
to new habitats. If the new plants have natural predators
in the new habitat they do not significantly change the balance
of the ecosystem. On the other hand are
plants or animals that lack predators in their new habitat
and have an aggressive growth pattern.
When the ecosystem cannot keep a plant’s
population within a manageable range, the balance of that
ecosystem is tipped, causing the rest of the native species
to suffer, decline or become extinct. The purple loosestrife,
for example, hails from Europe where many insects feast on
it, keeping its population in check. In this country there
are no bugs or animals that feed on it or kill it, and so
it spreads several million seeds every summer. Additionally,
it will re-grow from a cutting, making its removal from an
area very tricky.
|
What invasive species are most prevalent
in the Champlain Basin? |
 |
 |
 |
 |
 |
|
Buckthorn | Eurasian Milfoil
| Water Chestnut |
Honeysuckle |
Purple Loosestrife |
Tartarian,
Morrow, and Belle’s Honeysuckle (Lonicera spp.)
are all types of invasive honeysuckle that live in Vermont.
Reaching heights of anywhere from one to 16 feet, this
creeping vine or thicket-creating shrub strangles trees
and shades out much of what is below it. The plant retains
its leaves long into the fall giving it an advantage
over native plants. Tartarian honeysuckle is native
to central and eastern Russia, Morrow honeysuckle is
native to Japan.
|
A
deciduous shrub or small tree, with oval shaped leaves
with teeth lining their edges. The flowers are a greenish
yellow. It has both a glossy and dull leaved varieties
(common and glossy buckthorn). Buckthorn lives in open,
wooded upland. Common buckthorn is native to Europe,
but grows in Asia. Glossy buckthorn is native to North
Africa, Asia, and Europe. The buckthorn reproduces
often and has an extended growing season, and re-sprouts
with ease. The shrub creates dense thickets, able to
shade out many other plants. They most easily infest
open areas. |
A
small, thumbnail sized, black and white striped, freshwater
mollusk hailing from the Caspian and Black Sea regions
of Eurasia. They were discovered in Lake Champlain in
1993, thought to have arrived via the Great Lakes in
the ballast tanks of boats and ships. Zebra mussels
cause damage on many fronts. They are known to attach
en mass to residential, municipal, and industrial water
intake pipes, ruin boat hulls and engines, and carpet
rocks in the water and on the shore.
The mussels are decimating other
native mussels by attaching to their shells, making
it impossible for the native mussel to open its shell
to feed or breathe. As they eat large numbers of plankton
in the water, normally eaten by other members of the
Lake Champlain food chain, the organisms in the food
chain above them become affected and a side effect,
the water becomes clear. |
First
discovered in Lake Champlain in 1962, Eurasian water
milfoil is a seaweed-like freshwater plant. It spreads
by breaking apart and re-growing, making the job of
containing it very difficult. Animals as well as people
can easily spread this plant all over the lake and into
neighboring lakes. |
Found
in the 1940’s, water chestnut displaces other plants,
provides little nutritional value to fauna, and creates
thick mats that transform a habitat. Luckily, the infestation
has limited itself to the Southern half of Lake Champlain. |
A
five-petaled purple plant native to Europe, purple
loosestrife can be found in the wetlands of Lake Champlain.
Once it enters a wetland, the loosestrife takes over,
choking out whatever native plants are living there.
By producing millions of seeds in one summer, as well
as having the ability to produce roots out of stem
shoots, it can easily take over its habitat.
Once it is established, the wildlife that call the
wetland home are pushed out as well, no longer having
native plants as their shelter. Not much can feed off
of this plant, so it does little to contribute to the
local ecosystem. The only thing it has going for it,
is its pretty color. |
Printable
Fact Sheet - For a printable summary plus
solutions to each invasive species listed here. |
|
How did these guys get here anyway?
60%
of invasive species introductions have arisen from horticultural
activity (arboretums, botanic gardens, gardeners) introducing
new species to an area. Conservation
activities by various governmental agencies are responsible
for about 30% of invasive plants as new species have been
introduced to an area for screening, windbreak,
and erosion control, but also to supply food and cover for
wildlife.
Accidental introductions
are responsible for the remaining 10%. For
example, purple loosestrife was first brought to the U.S.
in the hold of a ship via ballast water, as were zebra mussels. Also
some invasive species are in fact native to certain regions
of North America where they are not invasive. They get introduced
to a new region perhaps for ornamental purposes, where they
have no competition and can become invasive.
|
Why not just let nature take its course?
Why is it important to protect native species? If
we let nature take its course an invasive plant species
can significantly disrupt and alter long established habitats.
Without predators or plant competition the invasive species reproduces
at aggressive rates, out-competing native plants for sunlight,
nutrients and space and out competing native animals or fish
for food. As the native populations decrease or become extinct
the genetic pool within the ecosystem is reduced. Wildlife populations
within the ecosystem can find themselves without an adequate
food source. Smaller animal that depend on plants for food will
decline in numbers. The larger animals who depend on the smaller
animals for food are then without an adequate food supply and
so on up the food chain. Additionally a diverse selection of
native plants and animals keep an ecosystem
more resistant
to weather disasters and climate change as there is a wider genetic
pool of plants and animals to adapt to changing conditions. .
|
| The
best method is prevention. Clearing small infestation
by hand works well. Herbicides or burning are required
for larger infestations. |
|
Many
management techniques have been tried in order to control
this species: cutting, mowing, girdling, excavation,
and burning. |
| : there is little anyone can do about
this problem, save trying to stop the spread of the
animals. They are being closely monitored by the Lake
Champlain Basin Program and Vermont Department of Environmental
Conservation organizations around the Lake. More about
the Lake Champlain Basin Program’s monitoring
of the species at http://www.lcbp.org/zmmonitoring.htm. |
| Attempts at containing this aquatic
plant include mechanical harvesting (much like an underwater
lawnmower), hydroraking, building bottom barriers,
lake level drawdown, fragment barriers, hand pulling,
and biological control via a species of aquatic weevil.
It is almost impossible to contain this plant as it
can spread through humans (in boats) or animals breaking
off stems and carrying them to other areas within a
lake or to other bodies of water. |
| Unfortunately, budget cuts have left
the management of this at a standstill. The main methods
used to deal with this plant have been hand pulling
and mechanical harvesting. |
| Currently, chemical lampricides such
as Bayer 73 and 3-trifluoromethyl-4-nitrophenol (TFM)
are used in 13 streams and some deltas to attempt to
control the population. Low head barrier dams on Lewis
Creek (VT) and the Great Chazy River (NY) have also
been installed—hopefully this will alleviate
the need for chemical sprays in all the tributaries. |
| Many management ideas have been
tried including burning, pesticides, and pulling the
plant by hand. These have worked to some extent, but
only in small, young populations. A better solution
seems to be introducing the insects that naturally
control the plant in Europe, to the wetlands in Vermont.
After years of rigorous testing to ensure that these
non-native leaf-eating beetles (Galerucella spp.) would
not harm native plants or agricultural crops, they
have been put to work, controlling the loosestrife
population quite effectively. |
|
How can I as an individual help?
If you
are a boat owner, make sure that whenever you move your boat
from one body of water to the other, that it is free of zebra
mussels, one of the most dangerous and invasive of all the
species. The larva stage of Zebra Mussels is microscopic
in size so you cannot necessarily see the enemy here. Clean
your boat off when it has come in contact with infested bodies
of water and give it a good look over and throw any zebra
mussels in the trash. Drain all water from the boat, including
the bilge, live well, and engine cooling system. Dry the
boat and trailer in the sun for at least five days, or if
you use your boat sooner, rinse off the boat, trailer, anchor,
anchor line, bumpers, engine, etc. with hot water or at a
car wash. Don’t reuse your
bait! Leave it behind if used in infested waters—give it
to someone else if you’d like!
When swimming or boating
in an area infested with Eurasian water milfoil, try not
to break parts off the plant—this is how the plant spreads.
Learn how to identify invasive species and keep your yarn
free of them.
|
Other Invasive Species Resources on the Internet:
InvasiveSpecies.
gov - A Gateway to Federal and State Invasive Species Activities
and Programs. Has good profiles for each invasive species.
(http://www.invasivespecies.gov/profiles/main.shtml#aqplants)
Invasive.org -
Invasive and Exotic Species of North America (http://www.invasive.org/)
New
England Wildflower Society - Invasive plants (http://www.newfs.org/conserve/invasive.htm)
Zebra
Mussel Fact Sheet - Lake Champlain Basin Program
(http://www.lcbp.org/Factsht/Zebra2007.pdf)
|
|
|
| |
|
|
|
Saving Our Lakeshore and Natural Areas
Lake Champlain Land Trust One Main Street, Burlington, VT 05401 802.862.4150 or info@LCLT.org |
| |
|
|
