by Robert Varney, Maine Sunday Telegram,
August 31, 2003
Newspaper headlines across
New England tell the story: “Lake residents worry about wild growth of
weeds: “Foreign earthworms threaten forest health”: Maine’s milfoil
madness.” No, this isn’t
from your supermarket tabloids. Every
week newspapers in Maine and NE are reporting on invasive animals and
plants being introduced in areas where they didn't exist before and how
they threaten native ecology.
Like all NE states, Maine is
suffering from an invasion of these plant and animal species into the
landscape and coastal waters. At
least 45 species of invasive plants and animals now exist in Maine.
Plants such as purple
loosestrife...dominate many of Maine’s freshwater marshes and
forested wetlands, especially in southern and central Maine.
Once invasive species are introduced, managing and controlling them
is a significant challenge. That’s
why the Maine DEP is spearheading an effort to prevent the introduction
and spread of invasive species.
Last fall, DEP issued an
“Action Plan for Managing Invasive Aquatic Species.”
This pro-active, four-year plan focuses on educating the public,
preventing new invasive aquatic species and limiting the spread of
established populations. As
part of this plan, watercraft are inspected for milfoil and other invasive
aquatic plants.
Invasive species are a
concern for a number of reasons. They
generally lack predators or other natural controls and can tolerate a wide
variety of environmental conditions, which allows them to easily establish
self-sustaining populations. Once
established, invasive species threaten the natural diversity and abundance
of native species as well as the stability of entire ecosystems.
Native species lose in the competition for habitat, breeding sites
and food. As a result, food
webs are destroyed. The
economic consequences can be severe.
Among the most common
invasive species in Maine is the variable-leaf milfoil, an aggressive
aquatic plant that has infested at least 15 ponds and streams throughout
western, southern and central Maine. (note: this species has already been
found in neighboring Thompson Lake, Middle Range Pond and Lake Auburn).
Invasive species can be transported among water bodies
by boats and trailers.
This country spends hundreds
of millions of dollars every year trying to control aquatic invasive
species. Money is most wisely spent on prevention, since once and
invasive species takes hold, it is virtually impossible to eliminate it.
Controlling invasive species costs $200 to $2000 per lake-acre each
year. Research in Vermont
shows that invasive plants can cost shoreline owners more than $12,000
each in lost property values on infested lakes.
According to the Maine DEP,
if the state experienced a fraction of Vermont’s infestation rate just
in its five southern counties, the property value loss alone could exceed
$11 million and control costs could reach $2 million to $4 million a year.
These figures would be substantially higher when lost tourism
dollars, fishing and water sports opportunities are factored in.
We all need to realize that preventing invasive species will require hard
work. State, local and
federal governments must play a leading role in identifying and preventing
the spread of invasive species. But government personnel cannot be at
every boat ramp and constantly patrol every lake and waterway.
To face the challenge, we
need to quickly and dramatically increase the number of watershed groups,
lake associations, boaters, fishermen and citizen volunteers who can act
as our “eyes” and “ears” to catch and prevent these threats as
early as possible.
