Fly fishing

Different colors of the rainbow

Marques Parr on a Little Kern River Rainbow | Jeffrey Walters/Kern Valley Sun

Almost all small rainbow trout have “parr marks” along their sides. This is one of nature’s camouflage techniques. When one type of fish has just hatched, it serves as food for so many other fish, animals, birds, etc. These black, mottled markings are just another way to hide these fish from other predators. They are mostly found in shallower water, and as they grow rapidly they move into deeper water, losing those parr marks along the way.

However, if you’ve fished the creeks and streams that feed the Kern River, you’ll likely have caught smaller rainbow trout with these marks. Most of these fish are caught in shallow, narrow streams with crystal clear water and deeper pools. These little fish fight extremely hard for their size, which is surprisingly small, but how old are they, and did they come from fish swimming and breeding upstream?

The answer to these questions is not so easy to explain, but it is important to understand if you want to catch more fish. The smaller and narrower the stream, the more difficult it is to catch these wild trout, and even more difficult if that stream or creek has very little overhead cover, such as trees and brush. Becoming the “ninja” and being able to sneak over these water types is half the battle. The other half is deciding which fly or lure will work best, because once your offering hits the water, the fish are scared off.

Rainbow trout in the Kern River are primarily found upstream of the Johnsondale Bridge, where natural water barriers prevent stocked trout from spawning upstream. Most of the creeks and streams that feed the Kern River follow the same path; there are natural barriers that prevent stocked trout from spawning upstream. So how do these brightly colored little rainbow trout get to these creeks and streams? They have been around for a very long time and simply continue to do what nature tells them to do: survive, reproduce and continue to grow to adapt to their environment. Local biologists in this area know that this fish can be many years old simply because this little rainbow trout is only 8 inches long, brightly colored and has huge dark parr marks on all sides. The marking does not usually fade on wild trout found in these small streams; nature keeps them hidden.

The larger rainbow trout found in the Kern River lose these protective camouflage markings as they age, the more they move and hide in the water and the amount of food they consume. The bigger the water, the bigger the food source and the bigger the fish that live there. Stocked trout do not have these parr marks most of the time. Some restocking programs include “fingerlings” as part of the restocking program. Just be careful when catching these little ones; they are part of a fragile ecosystem.