Trout growth rate

[W4z]

Hi guys,

Something I've been wondering about for a while is how fast do trout grow? How old would a 25cm trout be?

I was speaking to a guy once and he reckoned that a fingerling would take about 3 years to reach 25cm. I never thought it would take that long, but maybe he is right as they do live in cold water and I suppose that they would be slow growing.

I also understand that a trout living in a lake or damn will grow much faster that one living in a creek or stream. I'd be interested to know in both situations how long it takes for them to grow.

Cheers

Waz

[oarderve]

it depends on the type of food they have . lake trout with smelt in the lake put on weight quickly .In Victoria after the drought some of the trout were over a kilo

in the first year As for stream fish they do it much tougher than there lake brothers

[luderick -angler]

As the others said depends on the environment and fish numbers lots of fish little food equals slow growth rates less fish lots of food quicker growth rate on average asides fuss with ideal conditions could be between 15 and 20cm in its first year.

[W4z]

Cheers for the replys. The main thing that got me wondering was hearing about some planned releases in damns and then wondering how long it would take them to reach legal size.

Does anyone know the life expectancy of trout?

[Outback]

About 10 years for rainbows

[W4z]

Cool thanks mate

[troutboy]

hi all, rainbow trout in impoundments live about 3 seasons tops, browns on the other hand can stretch that to a couple of years more

cheers troutboy

[foolforjesus]

I would say life expectancy for Rainbows could be anywhere up to 10 years depending on the quality & size of water they are living in.

Also, depending on the food source & quantity, they could put on 1kg per year.

So if your catching 5kg Rainbows, they would be around 5-8 years old I would estimate.

As for Brownies, they do tend to live longer and can grow much bigger.

It all comes down to quality of water/size & food source, and numbers of fish.

Cheers, Chris

[zook2001]

I've read about a fourteen year old brownie in a hatchery,having said that seven years would be an good age for a wild fish.

For rainbows three years is a mature fish and they might be lucky enougth to live another year or two, I 'd expect a 5kg rainbow to be five years old.

[Delraiser]

The general consensus from American sites is around 6 years for Rainbows, although you'd expect the odd fish to go on to reach 8-10.

This explains why the general size of Rainbows in comparison to Browns is smaller as they simply don't live long enough. It also explains why stocking levels need to be higher (along with a certain lack of natural recruitment)

[luderick -angler]

At the end of the day having done a lot of trout fishing in nz and fishing with some gun fishers and talking to doc hatchery guys a 45cn fish I a high growth rate protein rich source such as Taupo is about 3lb and 2 - 3 years old saying that I've seen a 18lb bow in a river they do get big! Browns in the other hand can get in excess of 40lb and 12 yrs old in paces like Patagonia