By Diane Tipton
Wildlife managers in Montana have increasingly
turned to DNA analysis to learn about the state’s
wildlife and their ways, with some interesting
results. DNA analysis can provide information
about the age structure of fish and wildlife
populations, identify remnant native populations
and point out where native and introduced trout
species may be producing hybrid fish.
Deoxyribonucleic acid, DNA, is a nucleic acid
molecule in the form of a double strand, spiraling
helix. The strands carry the biological information
that makes species and individuals within a
species unique. Wildlife researchers can analyze
the DNA extracted from hair, skin, blood, saliva,
a feather or other body tissue and organ samples
to identify species, sex and even the individual
that the sample represents.
For example, in some cases fishery managers can
analyze the DNA in a clipping from a fish fin,
such as a bull trout, to identify its home tributary—
the water where it will instinctively try
to return to in order to reproduce. The U.S. Fish
and Wildlife Service, in a collaborative fisheries
mitigation program with FWP, Idaho Fish and
Game and Avista Utilities, uses this technology.
Biologists capture adult bull trout below Cabinet
Gorge Dam on the Clark Fork River and use
a rapid genetic assessment process to determine
how far above the dam to move the trout so they
can return unimpeded to natal waters to spawn.
In other DNA-related work, Montana FWP, the
Rocky Mountain Research Station in Missoula,
and other partners are developing a new panel of
genetic markers for cutthroat trout, redband trout
and rainbow trout. The markers will provide data
to help researchers better identify patterns of fish
hybridization and the structure of fish populations
within drainages.
FWP fish biologists are also using DNA analysis
to learn if sauger—a native Montana fish—is
crossbreeding with walleye—an introduced
fish popular among anglers. During this work,
FWP biologists also found that sauger above the
confluence of the Yellowstone and Bighorn rivers
may be genetically distinct to that locale due to
many generations of isolation from downstream
populations.
On land, the Big Sky Upland Bird Association,
Confederated Salish and Kootenai Tribes and
FWP jointly funded analysis of sharptail grouse
DNA samples from across Montana collected
by the National Wildlife Federation
in Missoula, including museum
specimens from Sanders and Lake
counties collected in
1897. The goal was to determine if a sharptail
subspecies once occurred west of the Continental
Divide.
Researchers learned that western Montana’s
sharptail grouse were genetically similar to Plains
sharptails in Alberta, North Dakota, South Dakota
and Nebraska. They found that the Columbian
subspecies of sharptail was not present in western
Montana as previously thought. This study confirms
that wildlife managers could use birds from
eastern Montana’s existing sharptail populations
to restore sharptails west of the Divide should
resources become available to do that work.
Researchers have also used DNA to confirm that
Montana’s native fisher was not extirpated in
the 1960s as originally believed. Ongoing DNA
studies will further establish the fisher’s current
distribution, numbers and genetic origins in
Montana and Idaho.
In another use of DNA-based research, the U.S.
Geological Service’s Northern Rocky Mountain
Science Center, with FWP’s assistance, is working
on a model to predict the spread of wildlife
diseases in deer.
As a transmissible virus mutates, genetic markers
of those changes remain in the DNA. Wildlife
researchers are studying deer genetics and these
markers in the viruses that infect deer to learn
how deer move regionally and statewide and
where they commonly come in contact with each
other over time.
If successful, this study could lead to predictive
models of how viral diseases might spread among
deer and how fast. It may sound like science fiction,
but it is happening today, thanks to advances
in DNA analysis.
Nearby conservation and wildlife research labs
capable of DNA analysis include the U.S. Forest
Service’s Rocky Mountain Research Station
in Missoula, and the University of Montana
Conservation Genetics Lab in Missoula, where a
FWP fish conservation geneticist is located. The
Wyoming Game and Fish Wildlife Forensics and
Fish Health Laboratory in Laramie also performs
wildlife-related DNA analysis.
Diane Tipton is Montana Fish, Wildlife and Parks
Statewide Information Officer.
