THE NEXT WAVE
The need for good boat-cleaning practices
continues to grow as the next wave of invaders comes ashore. The New Zealand mud-snail was found in western rivers, including the Snake River in Idaho in the late
‘80s. It has since spread to several other
river systems, including the Madison River
near Yellowstone National Park. These small
snails, typically only a few millimeters long,
can reach densities of 750,000 per square
meter, and have the potential to disrupt
the food chains in some of our nation’s
best trout-fishing rivers. Anglers who wade
in these streams also need to take precautions to clean and dry their tackle and
waders between uses to prevent the spread
of the snail.
Didymo (or “rock snot”) is a more
recent invader, found in western rivers in
2004, and in Tennessee in 2005. It’s since
spread to at least 18 states. This freshwater
algae can bloom in numbers sufficient to
block sunlight and coat surfaces. It’s eas-
ily spread by contaminated fishing gear as
well as by boats. Hot water (140+ degrees)
decontamination will kill didymo on boats.
Waders and other fishing tackle should be
soaked in a five-percent solution of water
and dishwashing detergent ( 2 cups deter-
gent to 2. 5 gallons water) for 30-40 minutes.
Or tackle should be allowed to dry for at
least two days.
3,000 psi. The whole thing is powered by
a 4-kw generator and needs to be operated
by a trained professional. The trailer and the
large black pad that the boat trailer needs to
be parked on for water capture and recycling
attract a lot of notice at the ramps. The trailers rotated through about 30 state-owned
ramps last season.
“We answered a lot of questions and
cleared up some misconceptions about the
program,” says Heidi Wolf, the watercraft
inspection coordinator with the state DNR.
“Everyone was positive and supportive.
Boaters expect to get inspected. Now we can
decontaminate their boats, rather than turn
them away.” The Minnesota DNR expects
to purchase 20 additional units for use this
The more we do to slow or stop the
spread of aquatic invasive species, the more
time there is to discover innovative solutions
such as biological controls. With the help of
comprehensive inspection and cleaning programs, boaters can help turn the tide against
PHOTO: STEVE KRYNOCK
Michael Vatalaro is Executive Editor of