Outdoor Report: Tracking Montana's fish populations

FWP Fish Study.jpg
Posted at 10:21 AM, Mar 02, 2020
and last updated 2020-03-02 12:21:08-05

State fish crews spend a good portion of the year on the water collecting samples and surveying fish, but during the winter you will find fish crews holed up in a dark room.

During the winter you will find most fish crews, not on a lake or river, but holed up in a dark room over a microscope.

“For all those anglers out there these are kind of the behind the scenes surveys and studies that we do, that don’t a lot of attention, but help us draw a lot of conclusions about how to make the fishery the best possible fishery for the angler,” explained Adam Strainer with Montana, Fish Wildlife and Parks.

Fish crews across the state conduct a variety of wintertime surveys; from diet analysis to aging fish, in order to better understand a fishery’s overall picture.

"By now we have some idea of what went on this past summer, but now we are truly get a great cross section as to everything that is happening,” Strainer said. Whether it be starting on the bottom of the food chain with zooplankton all the way to the top of the food chain with predator, growth rates and aging.”

Biologists can age fish by their scales and spines but the go to aging structure is an ear bone called the otolith.

“The rings will tell us -- just like on a tree -- how old that particular fish is. We are also going to see what s out there in our population, is it comprised of older fish, younger fish or a bunch of fish in between,” FWP’s Heath Headley said.

While the work can seem monotonous, it is really a culmination of all the time spent on the water that make this winter work important in managing Montana s fisheries.

“It’s nice to get summarized and make heads or tails of what’s really going on out there. That’s the cool thing about it,” Headley concluded.

Fish staff can spend up to a month analyzing data.