Fishy Business: Handhelds Help Remove Invasive Species from Utah River

A Utah DWR field crew rides along in an electrofishing boat.

The Utah Division of Wildlife Resources (DWR)  is using rugged Juniper Systems handhelds in an innovative way: to remove an invasive fish species from the Green River so that native fish can flourish.

A DWR field crew first used the Allegro MX handheld, loaded with custom fisheries software, to monitor native fish species and remove invasive fish in a 2013 project along the Green River, located near Dinosaur National Monument in Utah’s northeast corner.

The field crew’s work involved boat electrofishing, in which the researchers ride along in a boat with electrodes protruding into the water. The electrodes send out an electrical current, temporarily stunning the fish.The fish float to the surface, where they are netted and inspected. 

Invasive fish are collected and removed from the river. Invasive species can degrade fisheries habitats and harm the ecosystem. Right, the Allegro MX handheld.

Every five miles, the crew stopped the boat and collected data on the fish. In a single day on a 12-mile stretch of the Green River, the crew caught 2,800 fish. 

When a native species was caught, the fish was given a passive integrated transponder tag. Data was collected about the fish, and then it was released. When an invasive species was netted, however, it was kept for later data collection, and then removed from the river. Invasive species — fish transplanted from another location — can outcompete native fish, degrade fisheries habitats, and harm the ecosystem.

With high-value native fish, the team took a GPS point and collected data on the species, length, weight, sex, ripeness, and more, explained Juniper Systems’ natural resources market manager Trevor Brown, who accompanied a crew.

Brown explained that understanding the location of native fish helps fisheries biologists determine the effectiveness of previous removal efforts: Are native fish prospering in areas where invasive species were previously removed? Location also helps biologists associate where native fish are caught with habitat characteristics, which helps guide more targeted invasive removal efforts.

Allegro MX handheld.

Because the Green River is a a major tributary of the Colorado River, the boat crews submit their data to a central database that supports a larger effort to understand the status and health of fisheries systems of the entire Colorado River watershed. The information is used to guide management and policy decisions, fish regulations, and fisheries research.

“Location-specific data can help biologists understand population and dispersal of both native and non-native fish at a macro level,” Brown said.

The Utah DWR made the switch to the Allegro MX after seeing its benefits, including its full alpha-numeric keyboard, which allowed for rapid, accurate data entry, as well as its extreme ruggedness, sunlight-readable display, integrated GPS, and RFID compatibility. 

The team even found the Allegro MX, rated IP67, could float — an additional bonus when working along a river in a shallow craft.

Brown customized the fisheries software for the Utah DWR field crews. The crews previously collected data using pen and paper, and then manually entering it into Microsoft Excel, a time-consuming and error-prone process. The custom fisheries software, available through Juniper Systems, reflects the data that needs to be collected, with required data fields and streamlined data entry. Because many of the Utah DWR crews are made up of seasonal workers, Brown designed the fisheries app to be easy to learn and use.

Biologists use the Allegro MX to collect data on the fish, including this endangered razorback sucker.

Northern Pike. Besides boat electrofishing, the fisheries software can be used for other applications, including an invasive fish removal application called fyke netting. Shaped like a bag with several hoops forming its structure, a fyke net acts as a funnel to trap swimming fish. The Utah DWR uses fyke nets primarily in the spring to trap invasive northern pike while they are spawning. After setting the fyke nets, crews return to check them and collect data on the trapped pike.

The fisheries software is also used for tributary electrofishing data collection, in which wader-clad crews walk along tributaries with electrofishing backpacks, shocking the water. As in boat electrofishing, the crews collect the invasive fish for later data collection, and they tag and collect data on native fish before releasing them.

The team experienced significant improvement with the new data collection process. “[The fisheries software] greatly reduced the data-entry time to the point where it has already paid for itself,” said Joe Skorupski, Native Aquatics Biologist at the Utah DWR. “Last year with three people, we took over 200 hours to enter, verify, and manipulate data. This year, it took one person 20 hours and errors were nonexistent due to the software and new data-collection process. I could go on and on about all the great improvements due to the handheld and the software.”

Since 2013, the Utah DWR has expanded its use of the Allegro MX and software for parallel projects, such as native fish sampling on fast-moving sections (Flaming Gorge) of the Green River, where fewer invasive fish are present.

Electrofishing probes temporarily stun the fish.