Do all stocked trout really die?

[BobG]

Someone mentioned in my smoke trout thread that stocked trout die if not harvested. I've heard this before.
That got me to thinking, is this nessesarily true? OK, everything eventually dies, so let's get that out of the way now. But, is it unreasonable to assume a stocked trout will not live a year or two (possibly longer) if conditions dictate?

Here on the Cape for instance. We've got prime conditions for trout to not only holdover, but thrive. Clean, cold water, with very deep holes to seek cooler water during the summer months. Many of these ponds have herring runs, providing incredible forage in the fall as the fry drop back.
Back in my ice fishing days, I used to catch remarkable browns and rainbows through the ice at John's pond. Many over 20", and football-like in appearance since they were still gorging themselves on 2-3" herring fry still trapped in the lake.
Several times over the years, I've been bored, and gone trout fishing well in advance of the trout truck rolling, and caught rainbows over 24" and browns over 4 pounds.

IMO, I think more trout survive in the ponds than we realize. They simply become 'feral' if you will. They revert to their wild ways, and become extremely selective and reclusive.;)

[Slappy]

Sounds like an old wives tale to me.

Most are harvested, but there are some that survive even in odd watersheds. I have caught trout in the Boston/Cambridge section in August--and many have told me all the stockies die from warm water by then.;)

There are plenty of other fisheries where stockies do quite well. Catch a Winnipesaukee rainbow and you will probably have a pot-bellied pig!!

[Onshore]

No they don't. Many trout carry over to another year - especially in deep ponds and large streams. I've caught tagged trout in NH Streams that were stocked the year before - especially from the no kill area of the Pemigewasset. I think that story came about because of some state's penchant for putting "some" trout in just about every stream; even those that dry up in summer..

[fleshfly]

far from truth, as mentioned given the right conditions they will survive and even reproduce, hence the wild rainbows & browns in some of VTs small rivers that haven't been stocked since the 70s.....

[bb1]

There called 'hold overs' where I'm from. But if they are from dirty water I would not eat them! :eek:

[HunterFly]

I catch hold-overs stockers every year. So in my experience, no.

Admittedly, the place I catch them is ideal for their survival though.

[Vincent]

On the cape I've caughten plenty of hold overs that were beautiful in size. In fact I prefer to wait because of it.

[jbrumberg]

I find the "holdovers" to be just as wiley as the "natives" :(. Jay (Trout 5 Jay 0)

[Scunz]

I didn't mean to infer that ALL stocked trout die......certainly there a few hold overs but not enough to create a sustainable fishery without restocking on a yearly basis. As you said, cold and deep water with plenty of forage fish will keep the bows and browns alive.....brookies I doubt very much.

[DAQ]

I never believed the theory that stocked trout die off.

I have even caught Rainbows around here that appeared to be getting ready to spawn. Over several days of fishing in a Western Mass stream I caught many females that were dropping eggs and males that were milting. I don't think dieing fish would waste the energy to produce eggs and milt.

D

[lhonda]

From http://www.fish.state.pa.us/images/pages/qa/stock_late_season.htm

Late Season Trout-Stocking
Mortality Rates

Question
I'm wondering about mortality rates for the trout you stock in the fall and winter. Do you put these fish in at this time of year so they can spawn in the spring? How many of them will live long enough to reproduce? Also, will they be around to be caught next season?

Answer
It is generally accepted by fisheries biologists that annual natural mortality rates for wild trout in streams range from 30% to around 65%. For hatchery trout, mortality rates are considerably greater. For example: A study was conducted by Commission staff to evaluate the survival of stocked brown trout (planted during the fall) from October until the opening of the angling season during the following April. As part of the study, four streams were evaluated. At the time that this study was conducted, the streams were closed to angling during the fall. As a result the study served as an evaluation of the survival of hatchery brown trout from fall to spring without the influence of angling pressure during this time period.
For evaluation purposes, all of the fall stocked trout were tagged with a small plastic tag. Return to the creel rates were determined by a combination of creel census and volunteer angler tag returns. Survival rates were determined by population estimates via electro-fishing surveys. The results of this study indicated that return to the creel rates of the fall stocked brown trout were very low, as only 4.6% of the fall stocked trout were caught by anglers the following spring. In addition, only 20% of the fall stocked brown trout were estimated to have survived the winter to become available to the angler at the beginning of the next season. Based on the results of this study, over winter mortality of fall stocked brown trout was approximately 80%.

Adult trout stocked during the fall and winter are intended to expand fishing opportunities beyond the traditional spring and summer time frame. By extending trout stockings throughout the year, we are able to provide greater variety for Pennsylvania's anglers. It is not likely that the adult trout we stock will reproduce in the streams, nor is that our goal. Adult trout stockings are designed primarily to support "put and take" trout fisheries in waters that otherwise could not provide much recreational sport-fishing without plantings. Those waters with viable naturally reproducing populations are managed specifically for wild trout.

[FlyFishFrostie]

The short answer is no, stocked trout don't necessarily die, other than from old age.

Here in Burlington, we add 600-800 'bows and browns to the town reservoir every spring from a private hatchery for the kids' fishing derby. The initially stocked trout are 8-12" long, yet I've caught holdover rainbows up to 16", and a few acquaintances have caught holdover browns from the reservoir of up to 7 lbs., so it is clear that some of these stocked trout survive and thrive for years.

However, the obvious keys to their survival are fourfold: food, water quality (i.e., acidity, which trout cannot tolerate, and oxygen content), water temperature, and nominal predation.

Lots of our stocked trout are eaten by the resident chain pickerel and larger bass as well as cormorants and blue heron.

Fortunately, the reservoir has decent insect hatches and lots of bass and panfish fry, so there's lots of food for the trout.

The shallows warm dramatically in summer, but fortunately there are cool springs in certain deep parts of the reservoir where the trout can endure the warmest part of the year.

The reservoir has an airation system that pumps air into the water, creating lots of bubbles in certain areas that may aid the oxygen content, although holdovers were being caught in our reservoir long before the airation system was installed. Some people have argued that the airation may disrupt the thermocline in the summer and make previously cool areas unduly warm for the trout.

However, one thing is for sure. While we add hundreds of trout annually, the reservoir is by no means overrun with trout, so there appears to be a huge mortality rate among the stocked fish in spite of relatively favorable conditions. Lots of big pickerel and decent largemouths, though.:brow

One other thought: many waters that contain "wild" trout never contained "native" trout, thus the wild trout in those waters must be descended from stocked trout. All of the wild rainbows and browns in the eastern U.S., for instance, have to be descended from trout that were initially stocked in those waters at some point.

[bb1]

At places like lake Quinsig here in Worcester, where the state put in pike & tiger muskie, stocked trout are like candy for them....no more (very little) smelt either.
I'm sure a lot of (cherry) stocked trout are taken by native predators, and not killed off by the elements.

[DAQ]

lHonda,

That is an interesting study. I wonder how well spring stocked fish fare. They would have more favorable feeding conditions when they are first introduced. And, I think they would be more able to adapt to winter survival.

[Doublebait]

Go to Walden around Thanksgiving. You'll see the biggest Trout of your life swimming close to shore....Yes they hold