I have always been curious about growth rates in browns. People ask me how much can a brown grow during a year. I give them the standardized response. It depends on many factors. Genetics have a little to do with it but the overriding factor is how much food does that fish have to grow on. If there are lots of trout in a stream then there is less food and the trout will grow at a slower rate.
When I lived in Germany I was told by a fish manager there that trout grew at a slower rate there due to the streams being fed by the glaciers and the streams were colder than the streams in the United States. That same German fish manager told me that wild trout in Germany seldom grow larger than 20 inches.
This brown was caught on a size 8 black wooly bugger with green crystal flash in a tiny stream in Southwestern Crawford County in 2008. This trout measured at an eye lash over 20 inches. It was released back in to the very unique hole. I took close up photos of the trout and noted a unique gill plate pattern.
In 2009 this brown was caught in that same hole. We measured the trout and took a couple photos and let it go. The trout was caught on a blue fox spinner. It measured 22.5 inches.
Afterwards I compared the photos and gill plates and this trout was the exact same fish caught one year prior. It was caught within 10 inches of where it laid the year before.
This trout was caught by my good friend Chien Goh on a large waterway in Richland County in 2011. The unique hook to his jaw was unmistakeable. Chien released the trout. I was the net man and saw the hole really well. That trout measured almost exactly 21 inches.
This morning I returned to that exact same unique hole that Chien had caught his hook jawed male. The first cast I was rewarded with this sweet male brown. It measured 23.5 inches. A check of photos confirmed it. It was the exact same fish.
The next time someone asks me how much a brown trout grows a year I am going to confidently say. 2.5 inches a year.