What is it?

Let's face it, fish are fun and exciting to catch - whether you're into popping brookies in a beaver pond, or addicted to the rush of hitting a fatty in deep water (no, I'm not talking about slapping Dennis Franz around in the swimming pool) it's just plain fun. From little kids, to us big kids, it's a hobby that's easy to get hooked on (no pun intended).

As a beginner (and sometimes even as an experienced angler) determining what you've caught can be a little difficult. Is it a Brown? A Rainbow? Thats a good question, so let's start with the main types of fish that you're most likely to encounter here on the rivers in Colorado (and some neighboring states):

Rainbow Trout
Brown Trout
Cutthroat Trout (native to the area)
Brook Trout

There are a lot of other fish species to be sure, but I think it's safe to assume that, since this is a blog about fly fishing, that the fish in question would be trout, and that the water would be of the river/stream variety.

With that, let's break these down and take a look at each fish and see if we can't bring a little order out of chaos and make the fish identification process a little easier (besides - I've got nothing but time right now).

The Unofficial Fish Guide

Rainbow Trout: ah yes, the famous Rainbow. The unwilling participant of many a joyful moment (for me, at least - not too sure about the fish). Introduced to the Rocky Mountains in the late 1800s, these are probably the most plentiful of the fish here, being that they're a popular product of the hatchery system.

Since they are members of the Salmon family, they have the potential to grow quite large given the proper conditions. With adequate food supplies, preferable water conditions and room to move about, these fish, on average, will hit the 16-24 inch mark provided they meet their expected lifespan (5-7 years). However, they can, and do, surpass the averages quite regularly, and it's not unusual to find Rainbows pushing the 30-40 inch mark and weighing upwards of 20+ pounds.

And being that these fish love to jump, it can be quite an impressive sight to see a 25 inch bow on the end of your line breaching the water like a whale as you frantically try to keep him on the hook. Sure, he may try to go deep and run a little, but for the most part, it'll be a well-fought battle of fish versus the strength of your line, up close and personal.

How do you know it's a Rainbow? Well, my sticky little friend, it's easy: the first clue is the red/pink colored stripe (the rainbow) that runs the length of the body, horizontally. The spots on a 'Bow are also smaller than other fish (in most cases - there are exceptions) and the body itself is usually lighter in color than it's counterparts. I say usually since the body color can vary drastically among Rainbows (from light to dark) but for general reference, it will be lighter in color (silvery). Also, the spots will encompass the entire tail section along with the upper portions of the body, unlike most Brown and some Brookies.

So, you've landed a fish, and you've identified it as a Rainbow, and it seems rather large - but is it considered a 'big' catch? I would say if it falls within the 20-26 inch range, you've landed yourself a 'large' fish. Anything above and beyond that and you've got yourself a submarine and you better hope that there's someone around to get a picture of it, otherwise, it's just a story to everyone else (like 99% of my blog).


Brown Trout: Like the Rainbow, the Brown was first introduced into Colorado waters in the late 1800s, and it's been my nemesis on many a fishing trip throughout the years. While most trout species can be elusive, it sure does appear (from experience and popular opinion) that these guys are tougher to catch than what would normally be expected. And the bigger they get, the smarter they seem to be which, unfortunately, cannot be said for me.

Also related to Salmon, the hearty Brown can reach massive proportions in the right conditions, which include an abundant food supply, stable water conditions and plenty of room to do all of the stuff that fish like to do. Since we're talking about rivers here, the average Brown is 14-21 inches, but can (and do) get much bigger. Like it's cousins, Brown trout can reach the 3-4 foot / 10-15 pound mark where river conditions permit, or if you happen to catch them migrating upstream from a lake.

Browns are also the more aggressive feeders of the trout world, eagerly (and I don't say that lightly) taking streamers or a well presented fly. Oftentimes, you can see a Brown on the move, looking for feeding opportunities. If you're lucky enough to get your line in front of him, the chances are good that you'll be rewarded with a solid hit. One time, while fishing the South Platte, I tossed a bead-head pheasant tail into a current only to see a Brown come downstream like a torpedo (from the far-side of the river) to hit my fly hard. Now that was an impressive display of aggression and it is one that I will never forget.

Brown trout tend to have a longer lifespan of approximately 7-11 years, and are very resilient fish, which means there are some whoppers swimming around out there in the rivers. They also tend to feed at night or in the early morning, which adds to their reputation of being hard to catch. However, being an opportunistic feeder, it's possible to catch yourself a Brown at all hours of the day.

So, how do you know it's a Brown on the end of your line? Along with the heavier olive or brown coloring along the back, this species has darker spots than a Rainbow (sometimes red with a black outline) which, as a general rule of thumb, does not entirely cover the tail. Also, the body coloring will be a yellowish (or cream) color. Keep in mind, like with all trout, these body characteristics can be different, depending on the river conditions, time of year, size and individuality of the fish itself.

So, is it a large fish, or a big fish? For a Brown, I would have to say that anything between 17-21 inches is a large Brown. And a nice one at that. Above and beyond 21 inches and you have yourself a bona fide hog (and hopefully a witness that is sober).

Hold the phone, you say. If Browns live longer than Rainbows, then shouldn't it stand to reason that the 'guidelines' for large and big should be greater for Browns as opposed to Rainbows? And to that I would say this: no.

And here's my logic behind that: as mentioned above, Browns can be a little more challenging to hook (whether real or imagined), and the larger / older ones even more difficult. Add to that fact that rainbows are more prevalent, and that would give you the method behind my madness. I know, it makes about as much sense as the BCS rankings in College Football.


Cutthroat Trout: Out of all of the trout species found in the rivers here, the Cutthroat is my favorite. It's also a native species to the Rocky Mountain states, and there are approximately fourteen sub-species of this particular fish. Because of this, I am going to narrow this section down to generic descriptions.

Going out on a limb here, I don't want to say that the Cutthroat is a total Homer, but they do tend to be a little more gullible than their brethren. But, if you're like me, and you like a fight, then this works nicely in our favor.

When hooked, a Cut's first instinct is to head to deeper water, which means they will run. And they'll run hard. And unlike other trout, they rarely jump (which increases your odds of keeping them on your line) preferring instead to roll, wiggle and go deep, which means you'll be hoofing it alongside the water to keep up with them. I've only hit the backing on my line once while fishing, and it was a Cutthroat that was the culprit. I've also spent plenty of time trying to ease a Cut out of a deep run in fast water - which, if you've never experienced that, is not the easiest thing to do.

Along with the fight, they are, in my opinion, the prettiest of the lot. However, due to the different sub-species that we have available here in the Rockies, I'll stick with general descriptions that should apply across the board. First and foremost, there is the red, pink or orange colored 'slash' that runs along the gill, under the throat and along the jaw. In addition, there may also be a red / pink stripe that runs laterally along a yellow / cream colored (sometimes silvery) body. As far as spots, they can be anywhere from big, dark and numerous, to light and few, to somewhere in between. However the spots do tend to be more concentrated (and larger) the closer it gets to the aft end of the fish and the tail fin itself will usually be covered.

In most cases, you can expect mature river-dwelling Cutthroats to fall somewhere in the 12-18 inch range, and, depending on the sub-species, can live anywhere from 3-8 years. Of course, these are averages, and the Cutthroat trout can, and do, grow much bigger (in particular, the hybrid Cut-Bow) in conditions that are favorable.

So, after a well-fought battle, is the fish in your net large or big? If you're staring at a Cut that is in the 15-20 inch range, you've got yourself a large fish. Any Cutthroat above 20 inches is big, and if you land a Cut-Bow pushing the 30 inch mark, you've earned yourself a cold one. Or three. As well as bragging rights for the rest of your life. "Mom! Dad's telling that stupid story about the fish again!"


Brook Trout: That's right, our little speckled friend, the Brookie, which was introduced to the Inter-mountain West during the 1800s. Technically this fish belongs to the Char family, and can be found in lakes, rivers, spring ponds and streams throughout most of North America. Rarely reaching more than 12 inches in length, they can hit sizes up to, and beyond, 15 inches. A friend of mine once hit a Brookie that was pushing 19 inches, and there are a lot of stories about 22+ inch Brook Trout being hit in shallow, smaller streams throughout the West.

While I can't vouch for the stories, I did see the picture of the 'monster' Brookie, so I can confidently say that at least one of them hit the 19 inch mark in some very small water. For the most part that would be the exception, rather than the rule, so expect your catches to be on the shorter end of the measuring stick here in the Western states. As a side note, they are the perfect 'gate-way' fish for the wee ones in your life, and the kids should get a kick out of the fight that these little 'trout' can put up when hooked.

Brook Trout are normally a dark green in color, with a multitude of spots, patterns and colors that adorn it's back and sides. Some colors that you can see in these bantam-weights are white, red, blue, orange, cream and black. The underside (belly) of these fish is normally an off-yellow to orange color, which can become quite deep during the spawn. Overall, they may be smaller than most, but they do tend to look impressive.

These little fellas don't have a lengthy life-cycle, usually only lasting 2-4 years at the most. And again, they really don't get too big here in the West, usually averaging in the 6-12 inch range when mature.

What's a large Brookie? Well, maybe one in the 8-12 inch range. And a Brook Trout that comes in over 13 inches would be considered big and, hopefully, you've got plenty of butter, spices and lemon to go with it.


At the end of the day, it's about being on great water and enjoying the outdoors that really counts. But, it is nice to be able to identify your catch. The size guidelines that I listed are just that: guidelines. And they're strictly mine, which means you may or may not agree with them, which is to be expected.

But having a point from which to start is nice when trying to identify and measure up your catch. After all, how else can you tell your stories and still remain relatively 'accurate' (wink wink) if you have no basis from which to compare?


Anonymous said...

theres no lake trout. like i said we can go to spinney and catch some real fish!

Anonymous said...

This is actually helpful (printed this out). Thanks!

Linda said...

again.....I think they are all the same fish!

Anonymous said...

Actually yes, it's a stunt fish ala Anthony Bourdain's No Reservations (if you've never seen the show this will mean absolutely nothing to you!).

Anonymous said...

I went fishing with the author of this blog at Deckers. He spotted a HUGE fish from a boulder and when I say HUGE I mean MASSIVE! This fish was pushing close to 35in. When I saw the size of this thing I sort of laughed inside thinking even IF he could hook this monster, the line would snap seconds after the miracle. This guy worked his way down to the water and perched himself on a few rocks and began casting.

Believe it or not, he hooked this beast and I couldn't frickin believe it. I was on my way down to help him net it (He was balancing on rocks and wasn't in the position to do it himself) and as he pulled the fish closer we could see how absolutely enormous this thing was. He almost had that fish in the net but there were so many rocks to get through that eventually the big guy broke loose (just about two feet from the net.)

Now, usually this kind of story comes from the fisherman himself and people don't believe it BUT I was there and witnessed the most solid and skilled catch I had ever seen. Keep in mind that this guy is not all geared up in expensive Orvis equipment and pole, but somehow he is always the one pulling in the fish and the big ones at that.

There was quite a crowd out there too and not one other person got so much as a nibble. Oh and did I mention he also hooked two other massive fish within twenty minutes of this one?

Anonymous said...

HA! That fish was a HOG, and I couldn't have hooked him without your direction from above, thanks to the glare on the water. Too bad we didn't get him in the net - nice colors, healthy and fat - wow, what a picture that would have been.

And lets not forget, you also hooked a nice one. Overall, not a bad way to spend three hours on a Tuesday afternoon, eh?

There'll be other days, and we'll get 'em - unshaved, on tattered 5x leaders and #22's no less, while trying to hit drifts that are tough as hell to peg. It's Guerilla fishing at it's finest, and I wouldn't have it any other way.

And it's nice to be able to share it with someone that can appreciate the art for what it is - you ROCK!

Anonymous said...

I always wanted to get out there and do some fishing in Montana. We have some great rivers out here in the east to. Nice pictures.

alice said...

Those fish are cute.