Wild, Native, Stocked, and Invasive Trout

Heritage Team
Jul 23
4 min read

Written by Martin Montejano

We love chasing trout species in the mountains. The natural beauty that we get to experience in this type of setting seems to go hand in hand with tenkara. Maybe it’s because of the origin of the style of fishing. Historically, the anglers who developed the style fished for native trout and char species in the mountains of Japan. A lot has changed since the days of bamboo rods and horsehair casting lines, and with that, many different trout species have been introduced to regions of the world outside of their historic watersheds.

Here in the United States, we have a lot of different species that swim in our waters. In the mix of all of the fish that tenkara anglers like to chase after, there is a mix of wild, native, stocked, and invasive trout (and char), as well as a blending of some of those categories. In this post, we aim to define some of those terms, and provide a few examples of species that fit into these categories. To kick it all off, we’d like to start with “wild trout.”

Wild Trout

When we talk about wild trout, we’re referring to the population of fish that live and reproduce in the river (or watershed) in which they, themselves, were laid as eggs, and hatched. The last bit there is important as there are instances where organizations will plant eggs in a river system, but many do not regard the fish that hatch from planted eggs as “wild trout.”

With that being said, it’s worth saying that there is a bit of nuance to all of these different terms, and as we continue through the sections in this post, we will try to address those subtle differences that define the type of trout we chase.

Native Trout

Native fish - trout in this sense - are species that live within watersheds in their historic ranges. They are the residents of the rivers and lakes in which their species evolved. A broad example of this would be rainbow trout on the west coast. While they are native to a large range of California, Oregon, Washington, and Alaska (as well as Canada), there are subspecies of rainbow trout that are native to specific geographic regions within those states. One of those species is the “Golden Trout” in the Sierra Nevada mountain range.

Now, here’s where we come back to a bit of nuance… While native trout live in their historic ranges, there are both wild, native trout, as well as stocked, native trout. We will expand a bit more on this in the next section.

Stocked Trout

Stocked trout are ones that are often raised in a hatchery, then transported to another location where they are released into the water. This may not always be the case, though. As we mentioned earlier in this post, there are instances in which eggs were harvested and planted in riverbeds. There are a handful of reasons why fish are stocked this way at times, but we won’t get too bogged down in the “why” in this post. I would like to mention that, while we would consider this first generation of trout hatched from planted eggs, we might consider their offspring that make up the second generation “wild” being that they were laid as eggs, then hatched, all in the same river system.

The planting of eggs is not by any means the most common way of stocking trout in a river. Most often organizations will stock more sizable trout (in the sense of fish ranging from 4 to 20 inches, for example) in a section of river. This is often done by taking fish from a hatchery, transporting them to a location, and releasing them into the water. You’ll sometimes see trucks stocking a section of water, but this isn’t the only way it’s done. Some states will stock high alpine lakes by plane, and these trout can sometimes make their way into the creeks or rivers in the watershed.

Addressing the end of the “Native Trout” section, there can be stocked, native trout species, bringing us back to the rainbow trout as an example. Rainbow trout are often used in stocking programs because they grow fast, and tend to be able to survive the hatchery environments well. In many of the waters along the west coast where they may be stocked, they may also be considered as a native species.

While they are often stocked on the east coast as well, they are non-native, and can be considered invasive. This brings us to the next term…

Invasive Species

Our goal in this article is purely to educate and familiarize the different categories of trout, and we don’t want to ruffle any feathers. With that said, some of the most sought-after trout species in the United States will fall into the last major category - “Invasive Trout”

This group is made up of any species that is introduced to an environment outside of its native range. Oftentimes this impacts the wild, native fish population as the cohabitating species have to compete for resources such as food or shelter.

There’s a reason why we’ve used rainbow trout as an example in the previous sections. Even though it is the trout that you’ll find on many vintage fly fishing art pieces, they are only native to the west coast of North America (and some parts of Asia). Outside of that range, they are widely considered invasive - so much so that they are on the International Union for Conservation of Nature’s list of 100 most invasive species. They’re not the only ones on the list either..

Even though brown trout are another sought-after fish in the fly-fishing community, they are on the list right next to rainbow trout. Brought over from Europe in the late 1800s and introduced to North American, they have become commonplace in many trout streams.

As we come to the end of this article, it’s worth mentioning that every state and region will have their own groups of native, non-native, and invasive species. We suggest reading through articles, or literature published by your state or local wildlife department to find which species in your region fall into which category. Another great reference, in regards to trout, is Western Native Trout Initiative. On their website they have a “Species” page that shows a large list of trout, char, and salmon species native to the United States.