Do catch and release (c&r) areas really protect trout? Do trout stay in c&r areas, or do they sometimes move to nearby catch-to-keep zones? Are mortality rates higher in catch-to-keep zones?

These are some of the questions Aaron is addressing with his master's thesis. Aaron has four study reaches on the North Fork and the mainstem of the White River. At each reach, he implanted transmitters into 40 rainbow trout ranging in size from 14-17 inches. The transmitters are inserted into the ventral body cavity proximal to the anus (see the photos). Half of these fish were captured in c&r zones while the other half were collected from catch-and-keep zones. Aaron has been returning to his reaches once a week to keep tabs on the movements and mortality rates of his subjects.

Arkansas TU members Dennis McCarty and Clay Henry and I caught up with Aaron as he collected his weekly data on the North Fork. Arkansas TU is assisting Aaron’s project financially. We launched a 20' river boat near Norfork dam and went to work. While Dennis, Clay, and I focused on negotiating the rocky shoals and shallow riffles, Aaron checked his radio frequencies for nearby trout. When we honed in on a trout, we dropped anchor and marked the location with GPS, as well as measured temperature, dissolved oxygen concentration, water flow, and water depth. Aaron will use these data to calculate each trout’s range and preferred habitat conditions.

Most of the trout have stayed at the exact location where they were captured last fall. For the c&r fish, this increases the odds of survival. Aaron’s work has shown that mortality rates are higher outside of catch and release areas. Sometimes his $225 transmitters end up on the bank, sometimes they just disappear. Aaron even tracked one into a cabin owned by a nearby resort! Regardless, this is valuable information. Aaron has found that angler induced mortality is significant outside the catch and release area.

The final stage of his study will involve capturing his remaining trout one year after he tagged them to not only get his expensive transmitters back, but also to look at an otilith, or ear bone, from each fish. The presence or absence of certain rare compounds in each otilith will, among other things, give Aaron an idea of whether or not the fish came from the hatchery. The presence of wild rainbow trout has not been documented in the White River system. The fish attempt to spawn each spring, but the success of their offspring in the highly variable flows is unknown.

Hopefully this final stage of his project will be as successful as his mortality study. Already his work will provide useful and interesting information for fishery managers.

(If you haven't already, look at these photos)