Off-channel habitat on the Chena

On July 30, 2014, I accompanied some scientists from Mark Wipfli’s lab at UAF on some of their fieldwork on the Chena River, where they are also studying Chinook salmon ecology. I hoped to learn something from what they’ve found, and vice versa.

We floated a section of the upper river setting minnow traps and gathering diet samples. We particularly focused on off-channel habitats, which may be important to the fish, especially in high-flow years.

A slow off-channel slough where a tributary enters the Chena
A slow off-channel slough where a tributary enters the Chena
A calm side slough along the Chena
A calm side slough along the Chena

These habitats aren’t a focus of our study because the fish in them have to cruise feed (swim around searching for food) instead of drift feeding. But it’s important to know what else is going on in our study system. And not just fish activity…

Bear tracks
Bear tracks
Wolf tracks
Wolf tracks

Working along the Chena for years during my Ph.D. research, I never once encountered bear or wolf tracks, although both species live in the area. It was a treat to find the well-preserved tracks of a bear and a wolf just a few feet from each other on sandbars just a short distance up one of the Chena’s pretty little tributaries.

A tiny unnamed tributary of the Chena
A tiny unnamed tributary of the Chena

An eagle watched over us, too.

Eagle perched above the Chena River
Eagle perched above the Chena River

There was also, at one point, a thick emergence of midges. The larvae and pupae of these insects are a major food source for juvenile Chinook salmon in the river.

Thousands of midges hang low over the water's surface.
Thousands of midges hang low over the water’s surface.

It was a beautiful day to be out on the water in Alaska and a benefit to both our projects.

Leave a Reply

Your email address will not be published. Required fields are marked *