12 – 15,000 birds dead of botulism near Pocatello, ID

Botulism outbreak at American Falls Reservoir is slowing down after a massive kill-

Die-offs due to botulism are often the result of standing, shallow, deoxygenated water on top of what are usually mud flats in late season. This is the indirect effect of the wet year in SE Idaho. Less water was needed from the reservoir. As a result it had more water in late season than for many years.

Bird die-off slows. Idaho State Journal.

A very unpleasant story. Perhaps different operation of the system of dams could have prevented the reservoir from being this full. This reservoir is not an isolated one, but part of a large system of reservoirs on the upper Snake River and its tributaries.





  1. Tilly Avatar

    If we can just shoot ’em, blast ’em, or oil their eggs, we won’t have to worry about them dying of botulism! Right, IDFG?

  2. Eric T. Avatar
    Eric T.

    wrong species Tilly. Pelicans weren’t effected, at least according to the linked article.

  3. kt Avatar

    Eric T. You haven’t been following the IDFG killing machine’s proposals to eradicate white pelicans.

    Tilly raises the issue of the murderous intent of the IDFG to kill many hundreds of white pelicans so they don’t eat largely exotic fish in some stagnant eastern Idaho reservoirs.Kind f a double standard here.

    And just how would all the pollutants running into the botulism reservoir along with drawdown levels – have caused the botulism … I do wonder.

  4. mikepost Avatar

    kt: this is a natural process that has nothing to do with pollutants or “murderous intent”. Botulism occurs in many places and does not require any influence from man to reach fatal levels, particularly with waterfowl. The myth that nature is pure and eternally safe if only left alone is just that. Should we avoid exacerbating the conditions, yes indeed, but disease and death are common even in the unspoiled parts of our world.

  5. Ralph Maughan Avatar
    Ralph Maughan

    I think there is unintended uman culpability in this die-off.

    By the way, it has nothing to do with IDFG’s rejected proposal to oil (and so kill) pelican eggs at Blackfoot River Reservoir and Lake Wolcott (another reservoir).

    The human factor is the failure to do anything about the unusual submergence of what are normally mud flats this time of year on the shoreline at the north end of American Falls Reservoir. This is a large reservoir on the Snake River.

    This unusual submerge provides the conditions for botulism to grow. The birds are not considered in the operation of the reservoir system not because of IDFG, but because of the Bureau of Reclamation and the irrigators’ desire to always store as much water as possible, and this year has had a surplus.

    They could have kept the reservoir water lower by releasing it. This water would have been captured by other reservoirs downstream, or by holding the water in upstream reservoirs.

  6. Tilly Avatar

    Yes, I realize it does not technically have anything to do with the pelican “control” proposal. Just drawing attention to the irony of IDFG’s concerned quotes. Concerned about birds in one reservoir… want to “blast” ’em in the other.

    Ralph, I hope you’re right that the pelican “control” is dead. But the last article I saw said FWS nixed it, but that compromise negotiations were continuing. So I expect a slightly watered down version to emerge.

  7. rick Avatar

    Botulism has killed an estimated 20-50 thousand birds near the Great Salt Lake this year. This is an annual event every summer. What is interesting to me, is that it is considered only a moderate kill off with death tolls reaching hundreds of thousands in some years. Unlike the situation that Ralph describes, these deaths are not related to any irrigation management.


Dr. Ralph Maughan is professor emeritus of political science at Idaho State University. He was a Western Watersheds Project Board Member off and on for many years, and was also its President for several years. For a long time he produced Ralph Maughan’s Wolf Report. He was a founder of the Greater Yellowstone Coalition. He and Jackie Johnson Maughan wrote three editions of “Hiking Idaho.” He also wrote “Beyond the Tetons” and “Backpacking Wyoming’s Teton and Washakie Wilderness.” He created and is the administrator of The Wildlife News.

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