2014 Lower Deschutes River Aquatic Insect Hatch Report – by Greg McMillan

2014 Lower Deschutes River Aquatic Insect Hatch Survey Report

Now Available

Our 2014 Lower Deschutes River Aquatic Insect Hatch Survey by Rick Hafele is now available on our website. Rick, with the help of several guides and experienced fly anglers, compiled over 100 hatch observations in this report.

This is a worthwhile read to understand the hatches on the lower Deschutes. It’s also essential reading to understand the changes in aquatic insect populations and their hatch timing.

The single most startling result noted in the survey is the disappearance of the Antocha crane flies. The participants in this survey aren’t the only ones to note the disappearance of the Antochas. Portland General Electric and The Confederated Tribes of the Warm Springs Reservation, owners/operators of the Pelton-Round Butte Dam complex, hired a natural resources consultant to do a biological survey of the lower Deschutes River. That consultant, in their report, has also failed to find evidence of Antocha crane flies.

How important is the loss of a species of insect in the lower Deschutes? If it’s an indicator of river health, the answer is very important. And we believe the Antochas are an indicator of river health.   We believe that the cause of their demise is the algae that now grows in the splash zone on river rock in the lower Deschutes. It’s in the splash zone that adult crane flies lay their eggs.

Deschutes Crane Flies by John Hazel

Deschutes Crane Flies by John Hazel

This algae, new since the switch to surface water withdrawal at Round Butte Dam, is likely the result of a change in nutrients being discharged from the dam. DRA has reported on this in several previous posts.

Antochas did have value to anglers. During the time of their mating, they were sometimes swept off rocks and made available to feeding fish. The astute angler could be very successful if imitating them at these times. But they had a more important role, and that was as part of the larger food chain of the Deschutes River Canyon. That food chain includes (but is not limited to) fish, birds and bats. The loss of Antochas must not be taken lightly.

Photo by Dave Hughes

Antocha Crane Fly

Special thanks to Rick Hafele for his expertise and diligence in creating this important publication. Also, special thanks to the guides and anglers who made this report possible (John Smeraglio, Sam Sickles, Alex Gonsiewski, David Moskowitz, Steve Pribyl, Steve Light, Evan Unti, Rick Trout, and Damien Nurre).

Lower Deschutes River Aquatic Insect Hatch Activity Report Authored by Rick Hafele

The Deschutes River Alliance (DRA) is pleased to announce the completion of the Lower Deschutes Macroinvertebrate Hatch Activity Survey Results report written by Rick Hafele, the acknowledged aquatic insect expert in the Pacific Northwest.

With a sense of deep appreciation for the work and expertise Rick Hafele put into this report, we announce that the report is available on the Deschutes River Alliance website.

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We also want to express our appreciation to John Smeraglio of Deschutes Canyon Fly Shop, Damien Nurre of Deep Canyon Outfitters,

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and Steve Light of Deschutes Angler Fly Shop for their combined contributions to the report.

Steve Light

Steve Light

This report documents, for the first time, what many anglers have been concerned about on the lower Deschutes River.  The bug hatches have changed.  Rick designed a data collection form for guides to use on the lower river to report their observations of insect hatches during float trips on the river.  The three guides who participated this year are all very knowledgeable regarding aquatic insect identification.

March Brown mayfly by David Moskowitz

March Brown mayfly by David Moskowitz

The news in the report is not good.  Something is changing in the lower river.  We can’t say yet what those changes are.  But we do know that it’s not just the  aquatic insects.  The river bottom has become increasingly covered with golden brown algae over the past few years.  We fear that the algae is linked to the changes being observed in bug hatches.  There are multiple documents now on our website that establish how we arrived at this conclusion.

Pale Evening Dun Photo by David Moskowitz

Pale Evening Dun
Photo by David Moskowitz

This summer we will be embarking on an aggressive science based data collection effort that will look for changes in water quality, document changes in algae production and identify the species involved.  We will also be doing a broader more robust collection of data regarding aquatic insect hatches.

Special thanks to the many that are helping making this possible.  Our state and federal agency partners have been essential to this undertaking.  The same needs to be said of the volunteers who are helping us.  And a very special thanks goes out to the Deschutes River Alliance donors who are making this possible.

If you would like to support the 2014 Hatch Survey and Report, please consider making a contribution today!

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