5 replies to this topic

[Phry]

So apparently I can't tell the trout apart.  All the photos I find online are more colorful than the fish I have photos of so I'm confused.  I guess people only post the really pretty ones!  Apparently the tank had Rainbow, Brown, and Brook trout.

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[Matt DeLaVega]

All main fish are rainbows. The more speckled ones in the background are brooks.

[Phry]

So why would these guys be less colorful than the fish in the guide photos? Variation?  Age?  Gender?  Mood?

[UncleWillie]

Most of the fish you see (edit: in the aquarium) are hatchery-reared.  These fish were hatched and raised within large concrete runs, and have a much different diet than their wild cousins.  Note the messed up dorsal fin?  This is common in trout from hatcheries.  Fins get bitten off, get rubbed and eroded from concrete sides of their outdoor runs, etc.

Edited by UncleWillie, 08 August 2016 - 12:36 PM.

[Phry]

Most of the fish you see (edit: in the aquarium) are hatchery-reared.  These fish were hatched and raised within large concrete runs, and have a much different diet than their wild cousins.  Note the messed up dorsal fin?  This is common in trout from hatcheries.  Fins get bitten off, get rubbed and eroded from concrete sides of their outdoor runs, etc.

 

Oh silly me, I forgot to include 'diet' in the possible explanations, though of course that can be a big factor (eg flamingos!)  That does make sense.
I wonder if that can ever cause problems with breeding colors, or if  it just undermines the normal natural selection driven by mate selection.  I guess it wouldn't matter if they were not meant to be released to the wild, but it can be confusing to those of us who come to learn to recognize our native fishies!

Edited by Phry, 08 August 2016 - 12:54 PM.

[UncleWillie]

 

I guess it wouldn't matter if they were not meant to be released to the wild, but it can be confusing to those of us who come to learn to recognize our native fishies!

Most of these hatchery raised fish (fish raised in concrete runs or "raceways") are in fact released into wild.  They are stocked across waters that meet temperature requirements that can support trout populations (at least seasonally).  A lot of the fish in N. Georgia, Western N.C., etc. are stocked for angling.  Of course, there are some waters that will hold naturally reproducing populations of trout (of stocked origin).  So although stocked fish are often beaten up after their time spent in raceways, their offspring can look quite different.  Of course, some hatcheries are better than others when it comes to the condition / genetics of their fish, and the conditions and densities of which they are raised in.

Edited by UncleWillie, 08 August 2016 - 01:53 PM.