Colorado has got to be one of the best places for freshwater fishing in the country, particularly in our rivers.

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We’ve also got some monsters you can catch as well.

Sometimes, things aren’t all that peachy in Colorado’s fishing scene.

For example, last year saw a shocking amount of dead fish washing up to the shore at Fort Collins’ City Park. This was due to low oxygen caused by excessive heat, which unfortunately could happen again very soon.

However, another strange occurrence is happening out in Eagle County that is negatively affecting Colorado fish.

Bizarre Sores Showing Up on Colorado Rainbow Trout

Colorado Parks and Wildlife
Colorado Parks and Wildlife

Recently, Colorado Parks and Wildlife announced that they are investigating strange sores showing up on rainbow trout in Colorado.

In particular, these sores were found on fish in Eagle County, with a CPW biologist named Kendall Bakich saying there have been other reported cases in the area in the past.

The reason behind the sores is not entirely known, but it is suspected that both stress and bacterial infections are major reasons.

How Did This Happen?


According to Vail Daily, a major reason why this could be happening to some rainbow trout in Eagle County is because of stress after mating.

Mating takes a lot of energy out of rainbow trout, which takes place in spring. In fact, it takes so much energy that it weakens their immune systems.

This means that bacterial infections, which are more common than ever with the urbanization of the area causing more affected runoff, are more likely to take a hold of these trout.

Fortunately, Eagle County’s brown trout population seems to have gotten away from this situation unscathed.

With the summer heat beginning to really warm up local waterways, we likely will be seeing closures for fishing at different points this summer so the rainbow trout population can recover.

Colorado's Biggest Fish Lurking Beneath the Water's Surface

Colorado's rivers, lakes, and reservoirs are home to around 50 native species of fish. In total, there are around 101 species of fish found here. Scroll through the photos below to see which fish grow to be the largest ones found in the Rocky Mountains.

Gallery Credit: Wesley Adams

These Are The Best Lakes For Fishing in Colorado

From a combination of sources, like and

Gallery Credit: Chris Kelly

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