Citizen Science: Nonnative Species Reporting App

Report Invasive Vertebrates, Invertebrates & Plants

Anglers and boaters can now help protect local waters by reporting nuisance and invasive species with the Nonnative Species Reporting App, developed by the Middle Colorado Watershed Council. This easy-to-use tool allows users to identify and report nonnative fish, mollusks and plants, providing real-time data to Colorado Parks and Wildlife (CPW).

Northern Pike

Northern Pike are voracious predators that use underwater structures as cover to ambush their prey. In the Colorado River basin, they predate heavily on native fish, including threatened and endangered fish species.

Smallmouth Bass

Small mouth bass are an invasive species that predate on and compete with native fish species. They are a popular recreational fish but can devastate native fish populations. If you catch a smallmouth bass in the Middle Colorado or Roaring Fork watersheds, it should be reported on the Non-native Species Reporting Application.

Burbot

Burbot are large, long lived and can travel extensively across a watershed. Their large size and mouth allow them to predate on even adult sizes of native fish species.

Invasive Mussels

If you encounter either quagga or zebra mussels in the Middle Colorado Watershed you can report them with the Nuisance Species Reporting Application.

Eurasian Watermilfoil

Colorado Parks and Wildlife’s Aquatic Nuisance Species section has deemed Eurasian watermilfoil as the worst and high priority aquatic noxious weed in Colorado. It can form dense mats on the water’s surface leading to interference with agriculture and hydropower operations as well as recreating activities such as boating, fishing, or swimming.

New Zealand Mud Snails

New Zealand mud snails are a threatening invader in Colorado. They can attach themselves to gear and survive several days out of water. In 2022, New Zealand mud snails were detected in the Middle Colorado watershed near Parachute.

Walleye

Walleye are a non-native species that can predate on and outcompete native fish species. In the Middle Colorado Watershed, Rifle Gap is a popular walleye fishery. There is a fish screen below Rifle Gap to prevent walleye escapement. Any walleye found in the Middle Colorado River and Roaring Fork River watersheds outside of Rifle Gap Reservoir should be reported through the Non-native Species Reporting App.

Striped Bass

The striped bass is easily recognizable with seven or eight stripes running from behind the gill plate to the tail. The dorsal fin is separated into spiny and soft-rayed portions. As stripers mature, they become primarily piscivores or fish-eaters causing disruption in the ecosystem.

Scan the QR code to download the app and start reporting today!

How It Works

Identify: Spot a nonnative species while fishing, boating or exploring.
Report: Submit location details, description and photo through the app.
Monitor: CPW receives data, tracks and manages invasive species.

Why It Matters

Invasive species threaten native ecosystems by competing for resources, altering habitats, and disrupting food chains. Early detection is crucial for mitigation and removal efforts before these species become established. The app's centralized database helps identify trends and informs conservation strategies for the Middle Colorado and Roaring Fork watersheds.

Priority Species to Report

Invasive Fish (Vertebrates)

Nonnative fish like northern pike, smallmouth bass, walleye, burbot and striped bass pose serious risks by preying on and outcompeting native species.
Special attention is given to walleye in the Middle Colorado Watershed, especially outside Rifle Gap Reservoir.

Fishing Regulation Alert: Harvest of smallmouth bass and northern pike is encouraged in watershed tributaries. There are unlimited bag and possession restrictions in the Colorado River for walleye. Always check Colorado fishing regulations before harvesting.

Invasive Mollusks & Invertebrates

Zebra & Quagga Mussels: Highly invasive and easily spread via boats and gear.
Rusty Crayfish & New Zealand Mud Snail: Disrupt ecosystems and impact native species.
Prevention Tip: Always rinse, drain, and dry gear, boats and equipment to stop the spread. The rusty crayfish may not be transported alive from waters west of the Continental Divide. Learn more here.

Invasive Aquatic Plants

Eurasian Watermilfoil: Colorado’s most aggressive noxious aquatic weed, often introduced through aquarium dumping.

See someone releasing fish or plants into a waterbody? Report it immediately to Operation Game Thief at 1-877-COLO-OGT (1-877-265-6648), or email game.thief@state.co.us.