The Fish of the Roaring Fork Valley

---

Rainbow Trout – oncorhynchus mykiss

The range of the rainbow trout was once limited to watersheds draining west into the Pacific, a range that started with the Kuskokwim river in Alaska, ran down through Canada and the Northwestern United States, and ended in Mexico.  Because rainbow trout can tolerate a wide spectrum of water types, they have been transplanted extensively, and can be found across the United States. 

Rainbow trout can be identified by having light to dark green backs, a pronounced to subtle red to pink stripe that runs from gill to tail, and numerous black spots.  Shades of coloration can differ greatly across the country.

---

Brown Trout – salmo trutta

In their original distribution, these trout could be found in Europe, Iceland and the British Isles, and in select locations in Northern Africa.  People began transplanting brown trout in the mid 1800’s, and they are now found in almost every environment that is capable of supporting a population, worldwide.  Brown trout are fairly easy to recognize, but coloration can differ greatly.  Brown trout are usually dark brown or even dark green on top, with a strong to weak yellow side and underbelly.  They have numerous dark spots along their body.  They also have bright to soft red spots hallowed by blue.  The anal, pelvic, and dorsal fins usually have slender white stripes that run along the edges.

---

Brook Trout – salvelinus fontinalis

This fish is actually a char, but commonly referred to as a trout.  The brook trout’s natural range was confined to north eastern Canada, the United States, parts of the great lakes region, and in some headwaters of the Appalachians heading southward all the way to Georgia.  Because of its popularity as a sport fish, the brook trout has been transplanted across the United States, Eurasia, South America, New Zealand, and even parts of Africa.

The fish is relatively easy to identify.  Brook trout are usually have dark green backs, orange or red bellies, and red spots incircled by light blue.  The anal, pectoral, and ventral fins have slender white stripes on the outermost edges.  A truly beautiful specimen.

Brook trout can tolerate water that is extremely acidic, but their distribution is limited due to their need for colder water temperatures. Therefore, brook trout are oftentimes found in higher elevations.

---

Cutthroat Trout – oncorhynchus clarki

The cutthroat trout were originally found throughout the American west, western Canada, and parts of southern Alaska.  Prior to the introduction of non-native trout species, this trout had the broadest range in north America, and is the only native trout to states such as Wyoming, Colorado, Utah, and Alberta in Canada.  Unfortunately, the introduction of non-native species has greatly reduced the range of this trout, and led to many cases of hybridization. 

The cutthroat can be identified by the red to orange slits found on the lower sides of the jaw.  Cutthroat coloration differs greatly among subspecies, and, at times, this fish can be difficult to distinguish from the rainbow trout, due to similarities in appearance. 

---

Whitefish - prosopium williamsoni

The whitefish, or the mountain bonefish,(as we like to call it)is one of our native species.  They are found in the mid to lower Roaring Fork and the Colorado Rivers.