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Trout growth per year

3478 Views 18 Replies 11 Participants Last post by  Packfish
i was just curious as to what the average growing length per year trout grow.
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As much as I let them. :twisted:

Actually, I'm pretty interested in your question (the answer). I know there are a lot of variables involved such as what kind of food at what rate of intake, water temperature, growing season, and the like, but it would be nice to hear an "official" average. Good post.
I am interested in finding this out too. The other week I was talking to one of the guys who works at Cabela's about their fish. He said those monster rainbows in there were just over 1 pound when they first got them. So if this is true, I would imagine that trout can grow rapidly if given enough food. I don't know how credible this guy is though. He told me that those big humpbacked, hook-jawed rainbows they have are actually tigers. :? I am yet to see a tiger that looks like that from the pics I have seen of them. The ones at Cabela's even have the black mouths. Anybody care to give their opinion?
I've been to Cabela's recently and they didn't have any tiger trout that I recall. I'm pretty sure they'd stick out to me if they were in there. I love looking at tigers.

The fish that sticks out most to me is the monster hook-jawed, hunchbacked brookie in there. He's a crazy looking fish. Some of their bass are swimming around funny because their backs have humped up so much.

As far as the food supply goes, I'd say that all depends on the actual types of food they're getting. Minnows, flies, pellets, worms? The fly eaters won't grow as quickly as the minnow eaters or the pellet fish. The pellet fish won't taste as good or look as pretty as a fish that eats natural foods IMO, but they probably grow way faster with a plentiful supply of nutritious power pellets getting tossed to them all day.

The fish at Cabela's kind of scare me, though. I love staring at them, but the big bows really look cloudy in their tank. Maybe it's just the light overhead, but it just doesn't look right to me.
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I thought that thing was a brookie.
I have noticed that alot of the fish in their tanks are rather drab looking. They have the nastiest looking walleye and largemouths I've ever seen. The lack of color on the largemouths looks like they are from Utah Lake.
I was also always a bit curious as to how fast certain species of fish grow, especiallly trout. I heard that trout typically grow slower than other species, but I could be wrong. It probably has to do with food source, competiion, and each body of water, who knows?! :? I know carp grow like weeds, but I don't know about other fish!
It depends on trout species and if it's a sterile trout or not. It also depends on the enviroment. The same trout a year later let go in Porcupine Dam and one let go in any one of a number of Southern Idaho lakes will certainly have a difference in growth rate. The shallow Southern Idaho lakes are very fertile and the growth rates are pretty amazing. Also a sterile hybrid is going to have it's energy put in to growth where a non sterlie is going to have some of that put into reproduction. Also a trout in a river may gain a pound or so over a couple of years and trout in a fertile lake that doesn't have to fight a current make havea 3 to 4 times higher growth rate.
I just found this article regarding a study they did on Brook Trout in a fertile and a infertile stream in PA and how it related to their growth. I thought it was pretty interesting. Here is the link:


I also saw an article that said if trout are fed artificially they will grow 2-3 times faster compared to a natural food source. I think like Packfish said, it just depends on the body of water and the food source.
seems like the rule of thumb i heard was 3-5 inches a year depending on the factors packfish said.
Let's not forget that a young trout will grow faster than an old one. Last year's fingerlings are catchable size fish this year...That kind of thing.
The water temperature is a big factor in fish growth. Rainbows in water near 60 degrees year round, and assuming good food, will grow up to 12 inches in the first year. The same fish in one of our rivers will grow to 9 or ten inches the first year because for much of the year the temperature is between 40 and 50 degrees.

Right now in the Blacksmith there are lots of 10 to 11 inch browns. I believe these are the trout from last years spawn. (Ya, I may get some flack on this, but that is my story and I am sticking to it)

Have a great day!
Trout growth is highly dependent on environment. Biologists work hard to control factors that will keep fish growth at desired levels.

Read this paper on managing fish populations...it talks much about this subject:
Click on the above site and scroll down to this paper:
"A Simple 4-step Method to Manage for Quality Fishing"

Here is a sample paragraph: "Fishermen often underestimate how fast trout can grow and overestimate the time it takes to grow a trophy trout. Large trout are most often a function of fast growth rather than old fish. Several good trout streams in southern Utah lack spawning habitat and are therefore stocked with fingerling brown trout. Brown trout of known ages commonly reach sizes of 18-20 inches in 3-4 years. We have measured brook trout from Boulder Mountain lakes that reached 5 pounds after surviving only two winters (3 summers of growth). Brook trout stocked as 3-inch fingerlings and at a rate of 50 per acre grow to a size of about 13 inches and 1.0 pounds in a year. If the stocking rate is increased to 100 per acre, growth decreases to about 0.5 pounds in a year. If growth is rapid, then harvest of trout by fishermen is not a greath threat to quality fishing. In either Boulder Mountain lakes or brown trout streams, moderate annual harvest of 16-18 inch trout is replaced annually by younger fish quickly growing to this same size. Even if 80-90% of the 16-18 inch trout are harvested, they are replaced each year and there are still some fish left to potentially grow even larger."
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Wyoming2Utah, That was one awesome post! That is some seriously interesting information and the article was right... I did underestimate trout growth. This is one of the better posts I've seen so thanks to all who contributed.
I love the new avatar J-bass. Who needs a six pack when you can haul a whole keg.
Darn straight Nibble Nuts. Plus, I like the just entering the third trimester look. I heard its going to be all the rage this fall.
There are a lot of lakes that trout will grow at a 2" per month rate during the ice off to ice back on period of the year. They will start on Midges in the spring, move onto Damsels in the summer and back to a heavy concentration of midges again and perch or bait fish in the fall. If there are a large population of scuds in the water they are also high protein. Mantua, before the bucked biologist ruined that lake was full of scuds and the fish were very fat and fast growing. Minnersville and Ottercreek come to mind along with Lake Crowley in California and Stone Lake in New Mexico.
Right now in the Blacksmith there are lots of 10 to 11 inch browns. I believe these are the trout from last years spawn. (Ya, I may get some flack on this, but that is my story and I am sticking to it)

Sorry- Flack on that.
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