JEFF GUNDERSON
earthh d day
a y
Crawfish, Crawdad,
Crayfish
Whatever you call them ... they’re invading Oregon
BY HEATHER CYRUS
C
rayfi sh, also known as crawfi sh and
crawdads, are freshwater crustaceans
resembling small lobsters. People eat
crayfi sh or use them for fi shing bait, and
kids study them in classrooms.
According to Robyn Draheim, research
assistant for the Center of Lakes and
Reservoirs at Portland State University,
there is one known crayfi sh species
endemic to Oregon, the signal crayfi sh,
but there are three non-native species
competing with the natives for food,
shelter and space.
“The nonnative crayfi sh are very
aggressive. They take over the burrows of
native crayfi sh, leaving the natives exposed
to predators,” Draheim says. The nonnatives
are ferocious eaters compared to the natives
and can potentially introduce new diseases
to the water systems, she adds.
Where is Repair
in Lane County?
According
Accordi to Draheim, rusty crayfi sh,
now found in Eastern Oregon’s John Day
River, are native to the Ohio River basin
and were brought
into Oregon primarily
b
as a bait species.
Ringed
crayfi sh, another
sp
bait species,
are
found
mainly
in the Rogue
species
River to o our south. The red swamp or
Louisiana c crayfi sh, native along the Gulf
coast and introduced
commonly as a food
i
source (people
order
them
live to eat), have
(peo
been found in the Umpqua drainage and in
the upper Willamette.
W
Although
Althou there are no reports yet of
nonnative crayfi sh species documented
nonnativ
in Lane County, Draheim says that
“undoubtedly
they are there, but
“undou
reporting
is
inconsistent.
Most people
report
see crayfi
sh
and
that’s
the
end of the
cr
story.”
story
All
A three nonnative species are
used in the biological trade for
classroom
science kits. Teachers
class
purchase the
kits
in
order for students to
th
study a live animal.
Although it is illegal to ship nonnative
species of crayfi sh to Oregon, companies
are still doing it. Often teachers aren’t
aware of what species they are ordering
because the crayfi sh aren’t labeled on the
websites. The problem arises when the
school year is over, and the classroom has
a live animal to “get rid of.” Often classes
release the crayfi sh into nearby streams.
“Females can store sperm, so even if you
introduce only one crayfi sh, she can lay
eggs and start a new population,” Draheim
explains.
One company attempting to eradicate
this problem is Mountain Home Biological
in White Salmon, Wash. The company has
been offering the native signal crayfi sh
for sale, but not without complications.
“They are harder to keep alive, harder to
get a hold of and are not as successful as
the red swamp crayfi sh, but we are trying,”
said Rick Bretz, operations manager for
Mountain Home Biological.
Draheim agrees that the signal crayfi sh
aren’t as hardy as the nonnatives. They
don’t stand up to all the holding and
examining the children do in the classroom,
and sometimes die before the class is done
with its study.
“Although it hasn’t been easy, we want
to do the right thing,” Bretz said. Mountain
Home Biological won the Oregon Invasive
Species Council’s Invader Crusader award
Feb. 22, 2011 for its efforts in providing
native crayfi sh for sale.
Draheim says there are no effective
ways of eradicating the nonnative crayfi sh
once they enter a stream or river, and the
future effect of that species on the region is
hard to predict.
Crayfi sh aren’t Oregon’s only stream
invaders. The Oregon Department of Fish
and Wildlife lists the American bullfrog,
Asian carp, Chinese and Japanese mystery
snails, Chinese mitten crab, common
snapping turtle, New Zealand mud snail,
northern snakehead, oriental weatherfi sh,
red-eared slider, and the zebra and quagga
mussels alongside crayfi sh as its top
invasive water worries. à
Spring has Sprung
at B loomer’s
Nursery
Flowering Spring Bulbs Buy 3, Get 1 FREE
Floral Easter Baskets w/ special deals inside,
Color Spots and Veggie Starts Arriving Weekly
Do you hate
tossing something
when all it needs
is a small repair?
Repair2ReUse
supports the local
community and
reduces demand
for mining and
manufacturing
systems that
endanger our
climate and
environment.
A directory of local repair
services is now available
at Repair2ReUse.org
89719 Armitage Rd. Eugene, OR 97408 (541) 687-5919
Facebook: Bloomer’s Nursery
(or call 682-4339 for paper copy)
From small appliances to
sleeping bags and lampshades
to lighting fixtures—you can
find a repair service, learn
repair tips, recommend new
listings, and share your repair
stories.
Please visit
Master Recyclers at:
Sustainable Building
Advisor Certificate
Program
Convenient classes held one Friday
& Saturday per month for 9 months
beginning in October
Northwest Energy
Education Institute at
Lane Community College
FREE INFORMATION SESSION
Wednesday, June 15th 6-7pm
Eugene Public Library, Tykeson Room
To attend, RSVP @ 541-463-3154
QUESTIONS? VISIT WWW.NWEEI.ORG OR CALL
(541) 463-3154
APPROVED BY AIA FOR 100 CES LEARNING UNITS
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EUGENE WEEKLY APRIL 21, 2011 19