by Nancy jo Tubbs
The International Wolf Center relies heavily on scientific research
to provide facts about wolves that can be shared with the world.
Radio telemetry is one such research technique that has dramatically
expanded our knowledge of wolves. Visitors to the Center in Ely
learn about radio telemetry by actually venturing into the forest
to track wild wolves. While this is the most exciting way to learn about
wolves and wolf research, technology gives amateur researchers another
What is Radio Telemetry?
Radio tracking uses radio signals to locate animals and follow their
movements. Scientists have used this method to learn about many
species, including elephants, small birds, whales and wolves. More
than 700 wolves have been tracked in northern Minnesota in this
way since 1968.
First, a radio transmitter housed in a collar is attached to the
animal. When data are collected and transmitted over a distance,
the process is called "telemetry." From a distance, the researcher
uses a radio receiver and directional antenna to home-in on the
signal and follow it to the collared animal. Wolves travel so far
and wide that biologists usually use airplanes to track them.
Radio telemetry is used in several ways. An activity detector
in a special collar can be set to record the animal's activity over
a 36-hour period. Data can be downloaded by the researcher, who
sends a coded signal to the collar and then listens to the collar's
reply. These special radio collars can also be equipped with darts
holding a tranquilizer, which can be triggered from a distance.
This allows researchers to easily recapture an animal.
Satellites are being used in telemetry too. One type of radio
collar sends its signal to a satellite to forward the wolf's location
to a ground receiver. The newest collar uses a "Global Positioning
System" (GPS) to read its location from satellites every 15 minutes
and store the information, which is downloaded after the researcher
sends a signal to drop the collar off the wolf.
How Do Researchers Use Telemetry to Track Wolves?
First, the researcher live-traps a wolf. One method uses a foot-hold
trap that has been modified to minimize injury to the wolf. The
wolf is drugged so that it can be measured, given blood tests, fitted
with a radio collar and released.
The researcher can home-in on the collared wolf from about 30
miles away by airplane. Once the wolf is located, biologists record
where the wolf is, what it is doing, and how large its pack is.
What Have We Learned?
- Radio-tracking of wolves has produced information
such as these important wolf facts:
- Wolf packs each live in separate territories. In Minnesota,
territory sizes range from 30 to 150 square miles.
- Wolves in Minnesota usually disperse from the packs in which
they are born at one to two years of age.
- Dispersing wolves may travel straight-line distances of more
than 500 miles.
- Minnesota wolves have dispersed into Wisconsin and Michigan
and helped repopulate those states.
- Dispersing wolves seek areas without wolves, find mates, and
in this way start their own packs.
This activity is designed for children ages eight and older.
You will need a computer with internet access and a
Wild Wolves Activity Kit.
- To begin, click on "Track Wild Wolves." This link is found on
the home page and on all left-strip menus on the Web site.
- Select a wolf to study. You can read background
information on the animals studied in this project. For example,
you will read below about wolf #643 who is a female, aged two
to three, collared in the summer of 1997 and a member of the Perch
- Return to the main tracking wolves page. Pick one of the two
ways to access the telemetry data.
- Find your wolf's number in the list and select a date.
Check the number of entries logged for your wolf. If very
few entries are recorded, you might want to choose a different
- Download a copy of the entire telemetry database to use
in your own spreadsheet or database program.
Here is a sample of information on wolf #643.
| The number of collared wolf
|| The date of the Telemetry reading
| The time of the telemetry reading (10:50
|| Type of fix A=arial
| Township number North (located on the
left edge of Superior NF map)
|| Range west (Located on the bottom edge
of Superior NF map)
|| Section number in surveyed township (Southwest
corner of section 23)
|| Description of location using distance
from landmarks (2 miles south of Little Lake)
||2S Little Lake
| Activity r=resting s=sleeping t=traveling
|| Associates, other collared wolves located
in the same pack
|| Tally of wolves seen (4)
|| Could be more? Speculation about the
existence of more wolves unseen. Y=yes, N=no
- Use the Superior National Forest map's township, range and section
information, given on the map's border, to pinpoint your wolf's
position on each date that it was observed. Find the square at
the intersection of township and range. Inside that 36-section
square, find the section number (each section is one square mile
or 640 acres). Under "Description" in the data table, note lakes
or other landmarks to help verify and pinpoint the location. Put
a colored dot or pin at each spot.
- Watch for patterns of movement. Over time you will usually see
how the wolf stays in a certain area. That is the pack's territory.
In the spring when pups are born, members of a pack go out to
hunt but regularly return to the den to feed the mother and pups.
After the pups are about eight weeks old, the pack may move to
a rendezvous site. And when the pups are old enough to join in
the hunt, the entire pack is on the move. Wolves that are 1 to
3 years old may travel all over as they disperse to make their
It's easy to track your own wolf with this activity. You can use the
data to estimate the size of the pack's territory. Compare one pack's
territory to another. Contrast a pack's territory to the amount of
land that a human family occupies. Your research career has begun!