I have a couple of questions about the rainbows I have been picking up. Some are quite ugly almost deformed in a bloated sort of way and I would assume these to be fresh stockers. (they also are poor fighters) And then I will catch some line stripping flyers that are healthy, streamlined and display all the characteristics of a typical rainbow.
Does anyone know how long it takes for that stocker to morph back into the classic rainbow appearance? Or is there something else going on that I am not aware of?
My TU chapter stocks a local creek with bows and theres always a few that are just terrible looking. I've caught some that have an almost square look to them! Scared noses and wicked fungus. I've noticed that in those waters it take the fish anywhere between a week or two to get healthier looking and act more "trouty". I'm guessing it has alot to do with the water, if its "trout water" ,cold enough, plenty of forage, unpressured and so on.
I am not a fish culturalist but have stayed in Holiday Inn Expresses' in the past so I'll take a stab at this.
Trout that are raised in the concrete runs of a hatchery live in a crowded environment. They are fed a processed pellet on a schedule and so they become gluttonous as a result of the enormous level of competition for the food when it is dispensed.
As the water flow is channeled into and out of the runs those fish that can maintain position to the head of the run are provided better living and growing conditions due to the improved water quality as compared to those in the rear of the pack. Besides the reduced oxygen level in the water as it flows through a run packed with perhaps 2 or more thousand fish there is a huge amount of detritus in the compound by the time it reaches the outflow point. This detritus actually turns the water into 'a compound' by the time it reaches high levels and contains dissolved food pellets & excrement which is high in urea. You can see where this is going right? Some of the fish are growing in an environment that is acid rich and oxygen depleted thus there may be a variety of maladies exhibited by some individuals.
Last but not least there is the noted lethargic nature that some of these hatchery fish demonstrate. When you consider the aforementioned conditions and then realize that all of the fish have grew / developed in a hydro environment that offered little in the way of actual current they are not fully developed muscularly. Besides the bone cartilage and organs, a fishes body is one big muscle and for almost every one of the hatchery fish those muscles are not in shape. The fish will often gather in areas of reduced current in an effort to replicate their former home even when free in a creek or river. Many hatchery reared fish will become mortality issues but some will adapt and survive.
I have no time lines for the adaptation and survival fish but I worked along with the Fish & Boat Commission in float stocking projects on Delayed Harvest waters in Pennsylvania for a few years and kept track of some data on the areas we stocked. The turn around time for fish to appear as resident seemed to be one year and the numbers that could be identified in any following year were small. Identification was "the Ard system", when a fish was caught examine the teeth and fins. A wild or one year holdover trout will have developed teeth whereas a stock fish raised as described above will have teeth that resemble fine sand paper on their upper and lower mandibles. Trust me on this, I have examined a lot of trout. The fins on a wild or one year holdover fish will be firm and well formed while the stock trout fins will feel relatively soft and often they are rough on the edges from either rubbing on the concrete of the runs or from various fungal infestations associated with the detritus and urea from the run also.
So there you have it, some are fat from gorging and some are sick from less than optimal conditions. Some will survive while others are sure to die. When you catch your trout check those teeth and fins and you will be able to make an educated guess on how long they have been resident.
Those fish are sick, sounds like parasites to me. Maybe even whirling disease.
Parasites can be a huge problem in hatcheries without a protected water system, from predators, or spread from outside cross contamination
It's hard and today with the addition of a special supplement that gives even the hatchery fish pink flesh, it's really hard. A trained eye can see a fin wear pattern and more that might give insight but what you are describing sounds like sick fish indeed.
In ny all stocked trout have one of there lower fins clipped completly off.. Doesnt seem to effect the fish though.
Sounds like a lot of work to me. And we're talking hundreds of thousands of fish that would need to be captured and handled. Not saying you're wrong, just that it seems extremely time consuming and unnecessary.
In drainages here that have both wild and stocked fish, clipping an adipose, or anal fin is pretty common.. that way they (F&G) can tell the players at a glance.
When you fish waters that have both kinds, you learn quickly to appreciate the wild fish.
Even after stockers hold over, I don't think they don't have the heart or smarts, of a healthy wild resident.
We have only one short stretch of water that's stocked, so with mostly wild fish, we can really feel difference when we hook up.
Fish health, much like human health, is determined by genetic and environmental conditions.
Place high concentrations of people in a compromised environment and our health tends to decline. Same with fish.
Also, when the fish's slime coating is compromised by handling or whatever, the fish ick (white stuff) is likely to attack.
It's much more common in heavy use areas and stocked fish in unnatural concentrations..
This is why I use a net all the time, and resist handling the fish whenever possible.
No pinning them on the ground or bear hugging please, treat'em nice.
Like I always say, "take care of your fishery, and it will take care of you!"
clipping the fins also helps in determining the survival rates of the stocked fish. they will go back into the waters where they stocked these clipped fish, and when they electro shock it, it will give them a quick estimate of the survival of the stocked fish. I've spent hours clipping fins at fish hatcheries i've worked at, its usually cold, boring work.