Unified Interior Regions
Region 5: Missouri Basin

USGS Science Centers in the Missouri Basin Region
For more information on what each center is doing in the Missouri Basin, please follow the links below!
Wyoming - Montana Water Science Center
Northern Rocky Mountain Science Center
Regions L2 Landing Page Tabs
At the capture site
At capture sites with road access, biologists drive to a trap with a bear inside to set up for collecting biological data.
An immobilized bear.
Biologists use a syringe pole to immobilize the captured grizzly bear. It takes approximately 10 minutes for a bear to become immobilized.
Ready to remove from the trap
Biologists have immobilized the bear and prepare to lift it out of the trap and onto the tarp for data collection. Once on the tarp the bear is easier to move.
Preparing for collection of samples
A biologist prepares to collect biological information from the bear they have captured. Biologists collect hair samples for genetic analysis, weigh the bear, and gather numerous measurements of the body, such as the head, paws, claws, teeth, etc. Overall condition of the bear is assessed as well, including a body fat measurement.
Getting the bear's weight
One of the first measurements taken is the bear’s weight using a quadpod and electronic scale.
Getting set up
Biologists are very careful to keep the grizzly bear under shade and protected from the elements while they collect biological data. Vital signs are monitored throughout the handling period.
Close up
The kerchief over the grizzly bear’s eyes protects it from dust and debris and reduces visual stimulation. The small tubing in its nose, known as a nasal cannula, delivers oxygen to the animal while it is tranquilized.
Assessing body fat percentage of grizzly bear
Field personnel use bioelectrical impedance to assess body fat percentage of captured bears. The procedure is similar to how body fat is measured in humans and is based on the resistance of body tissues to the flow of a small, harmless electrical signal. The electrical current is impeded more by fat tissues compared with tissues that are composed mostly of water, thus
...Measuring the bear's head length
A biologist measures a grizzly bear’s head length.
Westslope cutthroat trout and bull trout in the North Fork of the Flathead River, Montana.
Westslope cutthroat trout and bull trout in the North Fork of the Flathead River, Montana.