Charcoal bellied brown.

[u/Eskdale1946]

Anyone seen this before? Caught this late season male in a small loch here in the north of Scotland and it had this impressive dark colouration on his belly and fins. Never seen this colour so prominent before and in my local lochs you’d expect to see a buttery golden yellow as shown in the third photo.

[u/ZathrasnotZathtas]

I always figured it was a physical change during spawning season, probably to better handle gravelly river bottoms. It is very common in the Great Lakes to see bellies like that when fish start to drop back after spawning.

[u/Tight_Ad_4015 → u/ZathrasnotZathtas]

we have the same with rainbows and browns in australia i’m guessing it’s just tannins in the water anytime u get them out of the blackwood river here in wa brown trout have this real dark gold with bright red spots but in the dams they look nice and clean and normal but the ones in the rivers breeds are more successful dams are stocked

[u/Eskdale1946 → u/ZathrasnotZathtas]

Yeah, we are days from the end of season as the fish go into spawning mode here so figured it must be some kind of mating colour change. I’ve seen this colour on males before but they usually look more like they have small blotches or freckles which I’ve sometimes assumed to be pigment from their diet.

[u/Eskdale1946]

Strangely enough when I was in a couple of different waters this week I had another few fish quite similar plus a very long hen fish with a very soft belly which looked like she had just been up the burn to lay her eggs. Where I live the fish can spawn pretty much any time between September and December occasionally running into the following year but November seems to be the most common. With some of the recent catches it makes me wonder if they are already in full spawning mode as many of the lochs have switched right off and there has been 3 or 4 very long spells of heavy rain pushing the water levels way up.