How to be a Wild Trout Detective: Part I

Finding wild trout streams can be difficult. Anglers are notoriously tight-lipped about their favorite spots, so you won't find much first-hand fishing information available online. Most of the time you just have to get out and explore. Fortunately, there is plenty of publicly available data that can help you find the most promising streams before hitting the road.

Tools of the Trade:

Here are the programs/websites I use frequently to find trout:

Caltopo: This is a mapping with topographic maps covering the entirety of the US. It's especially convenient because you can overlay different map types with the menu in the top right corner of the screen. I usually use Google Hybrid as a base layer with USGS 7.5' Topos on top. You can also save maps marking stream locations to your Google account.

Google Maps: Although Caltopo can display Google Maps imagery, it has a less refined search feature, so Google Maps is still convenient for finding streams by name. Street View can also be useful in locating access points. 

Bing Maps: Bing Maps has a birdseye view that provides a more detailed look at the surroundings of  a stream than satellite imagery.

MA OLIVER: This site displays public GIS data on an interactive map. OLIVER is MA-specific, but I think some other states have similar sites. Search for "(insert state here) GIS" and see what you can find. If not, the useful GIS data is likely available in other, albeit less convenient, forms.

USGS Water Data: Few trout streams have USGS gauges, but those that do can be helpful in determining the size/temperature of nearby streams.

Fish Surveys: This data can be a bit difficult to locate, but it is probably the most useful. After all, there's no better way to determine a stream has trout than to look at electroshocking data. In MA this is available in the form of Water Quality Assessments. I'm not sure where to find this data for other states, but a google search for "(insert state) fish surveys" or "(insert state) electroshocking" should turn up some results.

Water Chemistry Data: I usually check water chemistry data last. Good water chemistry doesn't guarantee a stream will have trout, but it's useful to determine stream productivity after confirming trout presence. For MA I use the UMass Acid Rain Monitoring Project. As with fish surveys, this data is likely available in some form for other states, but it will take some research to find it.

Getting Started

So we know that there's tons of data available to help find wild trout.

Now what?

I like to divide my search into two phases: Stream Identification and Quality Determination.

Stream Identification

This is exactly what it sounds like: identifying streams that contain wild trout. My first step is to Google "(insert state) wild trout". Many state Fish and Game agencies document wild trout streams publicly, especially in states with relatively few streams. Even if there is no official information, this search will often lead you to news about wild trout. Oftentimes local newspapers will write public-interest pieces when TU and/or other conservation groups do work on trout streams.

If a Google search is unproductive, check out WildTroutStreams. They compile publicly available info on trout for all states with wild trout populations. For some states this means a list of streams; for others, like MA, it will lead you to fish surveys. Regardless of the detail of available info, it should point you in the right direction.

After a simple search and a look at WildTroutStreams, it's time to flex your "Google-Fu". Many people don't know about Google's advanced search functions. Here is a good summary sheet of the features - though you don't need to use all of these. You can use these search features both to find new streams and to learn more about wild trout streams you've already identified.

The feature I use most frequently is quotation marks to search for an exact word or phrase. For example:

wild trout 

Will get a lot of results that just happen to have both "wild" and "trout" on the same page.

"wild trout"

Will only get results where the two words were mentioned together.

Another useful search feature is the specific site search.

If you insert:

site:www.inserthere.com 

into your search, you will only get results from www.inserthere.com.

Putting these features together makes Google a powerful tool. Say you come across a blog or forum where people occasionally mention wild trout streams in your area. Rather than reading through post by post, you can search:

site:www.someflyfishingblog.com "wild trout" massachusetts

This will allow you to quickly scan through all the posts relevant to wild trout in MA.

Keep in mind that while advanced Google searches are useful in initial Stream Identification, they are not limited to this role. These search techniques will come in handy in future sections of this guide.

Stream Documentation

As you identify more and more streams, it can get tough to keep track of them all. Once you've accumulated a few potential streams, it's useful to compile a list in one place. I prefer to use a mapping program, as it allows me to see the distance between streams and the distance from home.

I use CalTopo. As I mentioned above, this site is great for displaying multiple map layers, but here we I'll focus on markers. First, you need an account. I linked mine to my Google account, but you can also link to a Yahoo account. 

Here's an overview of Caltopo:

Once you're logged in and familiarized with the use of CalTopo, you can start marking streams. The easiest way is to right click on the spot you wish to mark, then select "New" and then "Marker". You should see a window like this:

Here you can name your marker, add comments (I usually put down what species I know/think are there and why I think it should have good fishing), and change the marker style/color if you wish. I usually stick to the dot markers, but sometimes I change the color to indicate different species.

It won't be long before your map looks like this:

End of Part I.

Part II coming soon!