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A Response to Invasive
Species in the Lake
Champlain Basin
By Rachel Meyer, Sam
Fleming, Emily Gardiner
The Problem with Invasive Species
The presence of aquatic and terrestrial invasive
species poses several concerns such as:
- loss of native species
-alteration of habitats,
-over-exploitation of resources
-competition for ecological niches
*Economic and Ecological Consequences!
Invasive Species in the Lake
Champlain Basin
-over 48 invasives
in VT alone!
-lots of
research/data on
these species in
particular
-an effort to
increase
productivity with
amount of time
Invasive Highway
Purple Loosestrife
Lythrum salicaria
Purple Loosestrife
Lythrum salicaria
-herbaceous, perennial plant
-can grow up to 10 ft tall
-thrives in wetland areas
-populations have been spreading
at a rate of 155,000 ha/year in
U.S.
-costs up to $45 billion/year in
U.S. for control methods and
forage losses
-present mostly along CT River
and within Champlain Basin
-1989, 1996, 2005 distributions in
VT
Purple Loosestrife
Lythrum salicaria
-can adapt easily to varied
soil conditions
-can assimilate much higher
amounts of carbon than
other plants
-establishes in low-fertility
soils
-competes for pollinators
-extensive seed dispersal
Purple Loosestrife
Lythrum salicaria
Control Efforts:
-invasive plant quarantine
April 2002
-biological control:
Galerucella spp.
-chemical control
-prevention
-education
-increased enforcement
Eurasian Watermilfoil
(Myriophyllum spicatum L.)
Notes
Eurasian Watermilfoil
Introduction
• Non-native aquatic plant
• First noted in Lake Champlain
in 1962
• Known for rapid growth and
spread
• Commonly found in shallow
bays and along the shoreline
• Form dense beds
• No known methods for
eradication
Eurasian Watermilfoil
Ecology
• Native to parts of Europe,
Asia, and northern Africa
• Native types of milfoil rarely
grow as fast
• Stems can reach surface in up
to 20 feet of water
• Will readily grow in many lake
substrates (i.e. silty, sandy,
rocky)
• Reproduce from fragments
Eurasian Watermilfoil
Control
•
•
•
•
•
•
•
•
•
•
Education
State laws and regulations
Bottom barriers
Diver operated suction
harvesting
Hydrorake
Pulling by hand
Mechanical harvesters
Rotavating
Aquatic herbicides
Biotic controls
Alewife
(Alosa pseudoharengus)
Alewife
Introduction
• Native to the Atlantic
Ocean
• Invaded the Great Lakes
in 1931 and caused
dramatic decline in native
planktivore populations
• First discovered in VT in
Lake St. Catherine in 1997
• First noted in Lake
Champlain in Missiquoi
Bay in 2003...population
expanded rapidly in 2007
and 2008
Alewife
Ecology
• Population grows relatively
unchecked due to low
predator populations
• Experience seasonal die-offs
because not well-adapted to
fresh water environments
• Outcompetes many native
planktivorous fish
• Feeds on eggs and larvae of
important game fish
• Predation on alewife results in
Cayuga syndrome - increases
fry mortality
Alewife
Control
• Netting
• Predation
• Chemical - Retenone and
Antimycin
Water Chestnut
Trapa natans L.
• Forms dense surface mats
• Native plants can't compete
• Planted intentionally in the
late 19th century
• Seen in Hudson river in 1920,
LCP in 1940
• 5.8 million spent to erradicate
in LCP 1982-2004
Water Chestnut Locations
Notes
Zebra Mussels
Dreissena polymorpha
• dcvx
•
• Grow on any hard surface
• Highly efficient filter feeders
• Environmental impacts
o Good and Bad
• Economic impacts
o $65K a year, over 2 million
already spent.
o Tourism
What Can Be Done?
• Good question...
o Education
o Fines ($500)
o Observation
o Preventative measures
o Aquatic competition
Habitats and Rank: Effects Link (0, 0.5, 1.0)
Species
Open
Water
<6’
Open
Water
>6’
Rivers /
Streams
Developed
Forest
Herbaceous
Ag
Wetlands
Alewife
1
1
1
0
0
0
0
0
E. Milfoil 1
1
1
0
0
0
0
0
Zebra
Mussel
1
1
1
0
0
0
0
0.5
Purple
Loosestrife
0
0
1
1
1
1
1
1
Water
Chest-nut
1
1
1
0
0
0
0
1
IS total
1
1
1
1
1
.5
.5
1
Habitats and Rank: Impacts Link (0, 0.5, 1, 2)
Species
Open
Water
<6’
Open
Water
>6’
Rivers /
Streams
Developed
Forest
Herbaceous
Ag
Wetlands
Alewife
2
2
2
0
0
0
0
0
E. Milfoil 2
1
1
0
0
0
0
1
Zebra
Mussel
2
2
1
0
0
0
0
1
Purple
Loosestrife
0
0
0
1
1
1
1
2
Water
Chest-nut
2
1
1
0
0
0
0
2
IS total
2
2
2
.5
.5
.5
.5
2
Sources and Stressors (0, 0.5, 1, 2)
Ag
Urban
Roads
Forest
Fisheries
Marinas Dams
Parks
Indust.
Ex.
1
1
1
1
0
2
0.5
0.5
2
0.5
*Total across the board instead of breaking into categories
Acknowledgements
A special thanks to Meg Modley and Ellen Marsden!