Species

Five fish, and only two of them are from here

The New Mexico Trout Challenge asks you to catch five species of trout in New Mexico waters and send in a photo of each: Rio Grande cutthroat, Gila, rainbow, brown, and brook trout. That is the whole ask. It is free, there is no deadline, and nobody checks up on you.

It sounds like a checklist. It is not, quite, and the reason is in the list itself.

Two of the five are native. The Rio Grande cutthroat evolved in the Rio Grande, Canadian and Pecos basins, and it is New Mexico's state fish. The Gila trout evolved in the Gila and San Francisco drainages in the southwest corner of the state. They are the only trout native to New Mexico, their ranges do not overlap, and they never did. Standing in the Pecos, you cannot catch a Gila trout. In the Gila, there is no such thing as a Rio Grande cutthroat.

Three of the five were brought here on purpose. Rainbow trout arrived in 1896, from the Northwest, into Bluewater Creek near Grants and Eagle Creek near Ruidoso. Brook trout came from the southern Appalachians and brown trout came from Europe, both soon after. The railroads made it possible. Fry came west in milk cans and finished the trip by pack mule.

Nobody was doing anything wrong by the standards of the day. The people doing it thought they were improving the place. New Mexico's territorial game warden, reporting for 1909 to 1911, noticed the newly stocked rainbows interbreeding with the native cutthroat and wrote approvingly about it:

"These two varieties cross very readily, so that it is difficult now to find these distinct species… It has become a well-known fact to all students of fish life and culture, that crossing is beneficial."

The department's own magazine, looking back a century later, put the result plainly: that hybridization "helped put the native Gila trout on state and federal endangered species lists years later, and it reduced purebred populations of Rio Grande cutthroat to mere remnants in scattered headwaters."

Stocked and native are different objects

A stocked rainbow trout is a fish somebody put in that water, often this season, and can put there again next season.

That is not an insult. It is a legitimate way to run a fishery, and New Mexico does it well: the state stocks rainbows into water too warm in summer to hold trout year-round, which turns a lake that could not otherwise grow a trout into a place a kid catches one in January.

A Rio Grande cutthroat in a headwater stream is a different kind of object. It is the surviving end of a line that has been in that drainage longer than the drainage has had its current name. More than 120 conservation populations remain range-wide, more than 80 of them in New Mexico, and together they hold about 12 percent of the fish's historic range. A 2013 assessment found 86 percent of those populations sitting in high wildfire-risk country. Most are small. Most are isolated from each other. Each one is a meaningful fraction of everything that is left.

Gila trout are further along that road. Listed endangered in 1967, down-listed to threatened in 2006, and today reduced to five genetically distinct lineages. The whole species traces back to five surviving populations.

In July 2026, biologists pulled 78 Gila trout out of a creek in the Gila Wilderness ahead of a wildfire and flew them by helicopter to a hatchery in the north of the state. All 78 survived. Those fish were one of the five lineages.

Both are worth catching. Only one of them is irreplaceable.

You do not have to take that on faith, because the state's own regulations already draw the line. There are twenty named streams in New Mexico where the bag limit on rainbow, brown and brook trout has been removed entirely in order to protect natives, and the department explains why in one sentence: "Nonnative trout species can outcompete or hybridize with native trout species."

Three species, three different harms

Which is why the answer is not "nonnative bad."

Rainbow trout hybridize. They interbreed with cutthroat and with Gila trout and produce fertile offspring, and rainbow traits dominate. A few generations of that and the native fish is gone as a distinct thing without a single fish having been killed. This is why New Mexico is converting its hatchery rainbow production to triploid (sterile) fish, and why recovery work is built around barriers that physically stop nonnatives swimming up into a restored reach.

Brown trout outcompete. A New Mexico State University study of eight New Mexico streams found no evidence that brown trout prey on Rio Grande cutthroat at any life stage. They win by eating the food. In streams without browns, the flow of prey to cutthroat measured 16 times what it was where the two shared water.

Brook trout compete and prey. They take food and space, and unlike browns they eat cutthroat eggs and fry. They also overpopulate and stunt in the small streams they occupy here, which is why a stream full of six-inch brook trout is a worse fishery and a worse ecosystem than the same stream holding cutthroat.

And brook trout are not trout. Salvelinus fontinalis is a char, the same genus as lake trout, a different genus from every other fish on this list. That is why they cannot hybridize with cutthroat: the threat they pose is entirely competition and predation. It is also the easiest identification in the whole challenge.

None of the three did anything wrong. People moved them. In their own range in the eastern United States, brook trout are the imperiled native being pushed out by introduced rainbows and browns. Same story, different watershed, different villain.

What the challenge actually asks of you

On paper: five fish, five photos, one email, no fee.

In practice it asks three things more interesting than the paperwork.

It makes you travel the state's water. You cannot complete this from one drainage or one style of fishing. The Gila is a southwestern wilderness fish in small, tight, high-gradient creeks. The Rio Grande cutthroat is a northern headwater fish. The rainbow you will most likely take from a stocked lake or a tailwater, the brown from a wild river, the brook trout high and cold. Five species is a map of New Mexico's water, and finishing it means you have seen most of it.

It makes you learn to identify fish. The submission is a photograph, and it is judged as one. That is the pinch point of the whole program. What decides an accepted submission is not obscure: it is the difference between a Gila trout and a rainbow, or between a pure cutthroat and a cutthroat-rainbow hybrid, and the tells are visible in a photograph if you know which ones to look at. Every species page here leads with that.

It puts you in the country these fish have left. Completing this challenge means visiting some of the highest, coldest, smallest water in New Mexico, in the specific years when 86 percent of one species' populations sit in burn-prone country and the other species is down to five lineages.

You will be a visitor in a place with very little margin.

The challenge is longer than the list

Here is the thing the form does not capture. Finding the water is part of it. Reading it is part of it. Picking the fly, getting the drift, hooking the fish and landing it are all part of it. And then handling it well is the last part, and the easiest one to get wrong in a hurry.

It also has the best payoff, and the payoff is entirely selfish: a fish that swims off strong is a fish somebody might catch again in a few years, bigger, after it has spawned a few times.

Not certainly. Maybe.

That is the whole deal, and it beats the alternative, which is a fish that drifts off belly-up and does nobody any good, including you.

So the five species are a list with a finish line, and the rest of it does not have one. Both are the same challenge. That is why this site is a log and a set of species pages rather than a checklist.

Named waters, and no pins

Some of these creeks are known to us. They are not named here.

That is not caution. If the point of releasing a fish carefully is that somebody might catch it again in ten years, then publishing a route to the last water it lives in works against the whole idea. A list of where a rare fish still lives outlives the person who wrote it.

It is also not an invention of this site.

Start with what the programs themselves ask for. New Mexico's submission asks for a body of water per fish and no coordinates at all. The Western Native Trout Challenge asks for a state and a water body name, and no coordinates either. Two independent programs, one run by a state agency and one by a federal-state partnership, both landed on named-water precision and neither asks anglers for a pin. That is not an oversight. It is the resolution the people responsible for these fish decided was appropriate, and nothing here is going to be published finer than that.

The programs already treat release as something to account for. The Western Native Trout Challenge's submission form asks, for every fish, whether it was released and what gear was used. Those are not idle questions on a form built by a native trout partnership. The handling guidance on these pages is not an ethical layer added on top of the programs. It is what the programs are already tracking, said out loud.

The Western Native Trout Initiative says of its own maps:

"In some cases, the maps were constructed to guide anglers away from sensitive conservation populations or from areas where habitat cannot sustain heavy angling pressure."

That is the standard. A federal-state native trout partnership deliberately steers anglers away from certain populations, and declines to include two cutthroat subspecies in its challenge at all rather than send people at them. NMDOW names regions on its cutthroat page and then hands you off to its interactive fishing waters map.

If you want a specific stream, the state will tell you. That is the right place for it to come from: it comes with the rules attached, it is current, and it reflects decisions made by the people responsible for the fish.

If you finish this one, there is a bigger one

The two native species here, Rio Grande cutthroat and Gila trout, also count toward the Western Native Trout Challenge, a twelve-state program run by the Western Native Trout Initiative in partnership with state agencies and the Bureau of Land Management. New Mexico is one of the twelve, alongside Alaska, Arizona, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, Washington and Wyoming.

It works in tiers rather than as a single finish line. Expert Caster is six species across at least four states. Advanced Caster is twelve species across at least eight. Master Caster is eighteen species across all twelve. Unlike the New Mexico challenge it costs money, you register before you fish, and most of the fee goes to on-the-ground conservation work.

The practical point for anyone finishing the New Mexico five: your Gila trout and your Rio Grande cutthroat already count toward it. They are New Mexico's only two qualifying species, because they are New Mexico's only two natives.

Two species into a twelve-state program without having done anything extra.