Brook Trout

Introduced brook trout are beautiful fish, but are also prolific and aggressive, to the detriment of many native species.

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For his birthday, our grandson, Tucker, wanted to go fishing on a small stream. With a few choices in Island Park, we settled on Moose Creek, a meandering, log choked, jumpable stream that pours off the Fish Creek Plateau adjacent to the western edge of Yellowstone.

Moose Creek is set in a thick evergreen forest; a clear-water stream, chillingly cold and untouched by livestock grazing. Gravel beds and undercut shady banks provide perfect habitat for brook trout, an iconic, but invasive sport fish.

The brook trout, Salvelinus fontinalis, is a fish from the eastern United States and Canada where it thrived in clear cold waters in places like the Appalachian Mountains. There they were highly favored as a sport fish because of their stunning good looks and aggressive nature. In the late 1800’s, populations were started in likely habitats throughout the western US to expand fishing opportunities. Brook trout flourished in the West and for many years the program to expand brook trout populations continued.

Brook trout are members of the char family (along with bull trout, lake trout and arctic char), a different genus than our western cutthroat trout or even our other introduced trout, the brown trout (rainbow trout are introduced in most places in Idaho, but since steelhead are sea-run rainbows, they are native to the state). They are beautiful fish with green backs full of wavy black lines, red spots with blue halos on the sides and pectoral, pelvic, and anal fins marked with white leading edges set off by black lines. In the fall, the bellies of male brook trout turn orange, making them the most handsome of fish.

The fish we caught on Moose Creek were small, six-inchers were the trophies of the day, but they were plentiful and attacked our baits with a vengeance. This is pretty common for brook trout. They establish populations quickly, and in many places can over populate, leaving abundant, but small, adult fish. Other than places like Henrys Lake, 12-inch brook trout are usually trophies (a 17-pound 10-ounce lunker is the largest ever reported). That is one of the reasons why the daily limit on brook trout in Idaho is 25. They just can’t be harvested fast enough.

Like so many instances with introduced species, transplanting brook trout has usually backfired. The impacts of moving brook trout into new habitats has been dramatic. In the headwaters of many cutthroat trout waters, the cutthroats have been completely replaced by brook trout. According to the US Geological Survey, brook trout and other introduced trout were likely responsible for the near-extinction of Lahontan cutthroat in Lake Tahoe in the 1940s. Research in the Snake River drainage found that juvenile chinook salmon were 12 percent fewer in waters with brook trout than those without and that habitat improvement for salmon did not help when brook trout were present. From salmon to golden trout, brook trout introduction has disrupted native fisheries.

But it doesn’t stop there. Because they are so prolific, there are often far more brook trout in a given water than what the native trout population would be. These hungry mouths can reduce the number of emerging insects by as much as 36 percent. Not only does this impact the insects, but reaches into bird and bat populations by taking food that they depend upon. And, at least 16 species of amphibians have been severely impacted by brook trout introductions.

Brook trout are here to stay in most areas, but don’t feel guilty harvesting a mess for dinner. Native species will appreciate it.

 

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Help Idaho Wildlife

When we traveled across the state in October 2017, most of the vehicles we saw using the wildlife management areas did not have wildlife plates. Buying wildlife plates is a great way for non-hunters and hunters alike to support wildlife-based recreation like birding.

C'mon folks, let's help Idaho's wildlife by proudly buying and displaying a wildlife license plate on each of our vehicles! 

See below for information on Idaho plates. Most states have wildlife plates so if you live outside Idaho, check with your state's wildlife department or vehicle licensing division for availability of state wildlife plates where you live. 

And tell them that you heard about it from Nature-track.com!

Wildlife License Plates

Great news! as of 2024, there are three NEW designs for license plates. They still are bluebird, cutthroat trout and elk, but they are beautiful.

Idaho Wildlife license plates provide essential funding that benefits the great diversity of native plants and wildlife that are not hunted, fished or trapped—over 10,000 species or 98% of Idaho’s species diversity. Game species that share the same habitats (such as elk, deer, antelope, sage-grouse, salmon, trout) also benefit from these specialty plates.

No state tax dollars are provided for wildlife diversity, conservation education and recreation programs. Neither are any revenues from the sale of hunting or fishing licenses spent on nongame species. Instead, these species depend on direct donations, federal grants, fundraising initiatives—and the Idaho Wildlife license plates.

Both my vehicles have Bluebird Plates. I prefer the bluebird because the nongame program gets 70 percent of the money from bluebird plates, but only 60 percent of the money from elk and trout plates - 10 percent of the money from elk plates supports wildlife disease monitoring and testing programs (to benefit the livestock industry) and 10 percent from cutthroat plates supports non-motorized boat access.

Incidentally, in 2014, the Idaho Legislature denied the Department of Fish and Game the ability to add new plates or even to change the name of the elk and cutthroat plates (very specific) to wildlife and fish plates, a move that would have allowed for changing images occasionally and generating more revenue. It would seem that they believe that we Idahoans don't want a well funded wildlife program.

I think it is time we let the Legislature know that Idahoan support wildlife funding and that we would like to see these generic plates come to fruition.