Why the Grayling is Going Extinct

Grayling. Photo: George Wuerthner.

In 1991, I, with the help of Jasper Carlton at the Biodiversity Legal Foundation, petitioned the U.S. Fish and Wildlife Service (FWS) to list the Arctic Grayling (sometimes called Montana Grayling) under the Endangered Species Act.

My petition was prompted by the concerns of several Montana Department of Fish, Wildlife, and Parks Department (MDFWP) fish biologists. The biologists were concerned that MDFWP wasn’t showing much concern about the decline of grayling in the Big Hole River because they did not want to antagonize the livestock industry. I will get into the reason for this concern in a bit.

By the 1980s, I had a reputation as an outspoken livestock grazing activist, and the biologists needed someone to work outside of their agency to help save the fish. So they contacted me about the grayling’s plight and sent me the latest population trends and other materials to put together my listing petition. In other words, without the assistance of these dedicated biologists, I would not have had the science to petition for listing.

I am also indebted to Jasper Carlton, who had worked on listing woodland caribou in northern Idaho. Jasper, though not a lawyer, had studied the legal requirements for listing.

We pulled together a listing petition. And in 1994, the FWS determined that the Montana grayling was approaching extinction. Still, as was standard then, they said other species were in greater danger of extinction, so we received a “warranted but precluded” decision.

In other words, the grayling was gone from 95 percent of its original distribution, and the population trends were downward; without intervention, the grayling would likely go extinct. But the FWS had other species whose future was even less certain.

It is now 33 years later, and I am still waiting for the grayling to be listed. The story of the grayling is an example of how agencies and specific industries like the livestock industry work to delay, delay, and delay federal protection for the fish. My cynical view is that the agencies supposed to protect the fish hope they will go extinct. End of story. End of having to deal with a controversial species.


Grayling in Montana is a relic of the Ice Age. They are related to trout and salmon and, like these other fish, require cold, clear water.

Historically, grayling were native to flowing rivers in the Arctic Ocean, including the Missouri River. However, when Pleistocene glaciers moved south into northern Montana, they blocked the northward flow of the river.

Big Hole River near Wisdom, Montana. Photo George Wuerthner.

One of the ecological strategies of the grayling is migration. In the Big Hole River, grayling migrate as much as 50 miles between wintering sites in deep holes to spawning habitat in tributary streams.


Livestock production has several significant impacts on grayling survival. Irrigation withdrawals by ranchers for hay production in summer significantly limit flows in the Big Hole to the point where I have seen the river reduced to a trickle in some years.

Low flow on the Big Hole River due to irrigation withdrawals. Photo George Wuerthner.

Low water leads to higher water temperatures that can be lethal to grayling. Also grayling are concentrated in the remaining pools where they must compete with other fish for food, holding water, and hiding cover.

Manure from livestock leads to water pollution with greater algal growth and reduced dissolved oxygen.


Though the FWS repeatedly has determined that grayling is declining and may face extinction, MDFWP and the livestock industry have used delaying tactics. In 2006, the Fish and Wildlife Service approved a Candidate Conservation Agreement with Assurances (CCAA). The CCAA allows ranchers who work on grayling habitat improvements are protected against any future ESA requirements.

CCAA designation means that even if future research demonstrates that a new strategy could save grayling from extinction, participating ranchers won’t have to make additional changes in ranching practices.

Of course, it has taken years to determine whether CCAA contributes to grayling survival, and in 2014, the FWS denied listing based on CCAA implementation.

In 2020, environmental groups appealed that decision and won. However, once again, the FWS determined that the listing of the Arctic grayling was unwarranted.

Meanwhile, grayling numbers in the Big Hole River continue to decline, almost to functional extinction.

The latest lawsuit filed in January asserts that since the early 1990s when I petitioned for grayling listing, the Big Hole grayling population has declined by 50% or more. Big Hole grayling’s estimated 2022 adult spawning population is between 496 and 671.

As drought and climate warming continue, the sure way to give graylings a chance to survive into the next century is to provide them with more water in summer and to reduce the livestock destruction of riparian habitat, which maintains shade that cools water and provides grayling hiding cover from predators.


The FWS is fiddling while Rome burns. This delay is partly due to the influence of Montana’s Congressional delegation, which has pressured the agency to find any reason to deny listing. In addition, MDFWP, who are supposed to manage species like grayling for public benefit under the Public Trust Doctrine, is leery of listing because they do not want to antagonize the ranching community they depend upon for access to private lands for hunters and anglers. It’s important to note that all the fishery biologists I have had contact with are grayling advocates, but they do not control the decisions of MDFWP directors.

George Wuerthner has published 36 books including Wildfire: A Century of Failed Forest Policy