Don’t bet against redband rainbow trout

Posted

2021/05/Writers-on-the-Range-image-e1622514008324.jpg

By Brian Sexton
PREVIEW Columnist

I love fish — the way they look, the way they fry up, the secret lives they live under the water. And of all the fish in the sea, river or lake, I most prize those that descended from the great oceangoing salmonids, trout and char. 

For me, the king of them all is the Great Basin redband rainbow. It’s not because they always grow to enormous size (some do) or that they’re feistier than some of their cousins (many are). It is because they are the ultimate survivors. 

They’re underdogs, plucky heroes surviving on sheer force of will. Due to their high-desert environment, redband rainbows evolved to adapt to higher water temperatures and lower levels of oxygen than many of their contemporaries.

In my native state of Oregon, these survivors can be found in seven distinct ancient lake basins in the south-central and eastern part of the state. Once, their ancestors made pilgrimages to the ocean or a large sea, migrating from their natal tributaries to rivers and eventually to saltwater. There, they would feed and fatten up until they felt the urge to return to their birthplace and spawn, completing their life cycle. 

As eons passed, their migration routes diminished. Many redbands that lost access to the sea would utilize as a proxy the lakes and marshes that formed in the valleys between ranges. 

The fish persevere, but their lives today take place in a patchwork of streams and small rivers isolated from one another; genetic diversity is a concern. Once fish from neighboring streams might have accidentally run up the wrong creek from shared wetlands and deposited their eggs or milt, introducing new genetics to that tributary. In many streams, genetic mixing is now impossible. 

What’s more, many of the streams in Oregon were at one time stocked with brook trout or bass, species not native to redband territory. Both are voracious eaters and prolific breeders, and in many streams they out-compete the native trout. 

There are other barriers. Channelization of streambeds and the loss of bank shading along with the slowing of the streams increases the water temperature and lowers the oxygen to levels beyond what redbands can tolerate. 

But habitat loss from modern irrigation practices is perhaps the biggest hurdle the fish face. Irrigation projects have diverted water into canals where fish passage was never engineered or likely considered.

Unlike critters like wolves and bears that bring a cuddle factor, it can be difficult to find sympathy for a fish. Fortunately, the redbands have allies in their corner. Many progressive landowners are working with wildlife agencies to better protect streams from livestock, and they are installing fish ladders and screens to prevent fish from getting trapped in irrigation projects. Nonprofits such as The Western Trout Initiative, Trout Unlimited and the Nature Conservancy have provided critical funding for habitat restoration projects. 

In the Warner Lake Basin, the Oregon Department of Fish and Wildlife has been successful in working with landowners to improve habitat and, currently, a large habitat restoration project is underway on Deep Creek, the largest stream in the basin, near the Oregon town of Adel. 

The Deep Creek project will allow redbands to once again access the large wetland on the valley floor, an impossibility for decades because of irrigation diversions. The effort is a large-scale collaboration between nongovernmental groups, state, local and federal governments. 

Sadly, projects in some other lake basins may not fare so well. Places like the Goose Lake basin near Lakeview, Ore., may be damaged beyond our ability to repair them, so it’s critical that we identify streams that can be rehabilitated before it is too late.

I have used my fly rod to tease small redbands from tiny streams during lulls in camping trips or chukar hunting expeditions. In these streams, mature breeding fish may only be 6 to 8 inches long. I release them back to the turbid water and marvel that they survive in such harsh desert conditions. 

I wonder what the future holds for these tough fish. Will the rains return and restore water to the valley lakes? Will the ancestors of these desert refugees return and someday find their way back to saltwater and become mighty steelhead? 

Nobody knows what the future holds for any species on this planet, but I would never bet against the redbands.

Brian Sexton is a contributor to Writers on the Range, writersontherange.org, a private nonprofit dedicated to fostering lively conversation about the West. He lives in Oregon. Views expressed do not necessarily represent those of The SUN.