Pond Boss Forums INTRO Questions & Observations Brook trout max lifespan?

The trout pond has all brook trout in it this time around, and they are doing well at about 14 inches at age 1 year & 8 months. I expect them to be in the 16 to 18 inch range this fall.

Anyways, I've always harvested them at age 4. But I'd like to keep them at least another year and see how big they can get. Since really large brook trout are hard to find, I can pretty much ask whatever price I want for them and I've got a list of taxidermists that are waiting. Even one in Labrador, Canada which has me puzzled. But then I had a taxidermist buy a brown from me that lives near the White River in Arkansas, so go figure.

Some literature I've seen says that most domesticated brook trout don't make it past 4 years of age. Other literature I've seen say they could reach 5 to 6 years or even more.

My hatchery sources don't keep them too long so that isn't a good source of info for max lifespan.

Any of the fish experts here have any ideas or anecdotal evidence they can share? Maybe someone you know raised some brook trout or you worked at a hatchery or know someone that did? Or as a biologist, or budding fisheries student, or as a professor you may have a connection that may be able to answer this? (Hint, hint :-)

The risk here is I could hold them past age four and experience significant mortalities which would be costly to my investment.

I did try and keep two of my Lake Nipigon strain brookies past 4 a few years ago, and come the following fall they had perished as there was no evidence of them. However the Lake Nipigons were stunted by 45 degree raceway water when I got them, and were already 2 years of age at only 6 to 8 inches. The fish I have now are a cross between Lake Nipigon and Eastern Brook trout. They also averaged 10 inches at age 1 compared to the 2 year old fish that were only 6 to 8 inches. Even if I don't keep the present fish past age 4 they should be bigger as they started out bigger.

Anyone?

Thoughts?

In the wild I think brook trout would live well past 4 years. Especially in small mountain streams where their growth rates are quite slow and fish max out at a foot in size.. However, in aquaculture pond like such as yours where they are fed lots of food and have fast growth rates, I could see their life span being 4 or 5 years... I honestly don't know for sure though. I think if you kept a few fish to 4 years, you'd be OK, but past that you really run the risk of mortalities.

That's what I'm afraid of.

Well, I know nothing about raising trout (I'm going to try someday) but I would guess in the wild they can live to be quite old. Brook Trout are actually Char right? Just like Lake Trout. In Lake Superior, Lake Trout live to be VERY old. Lake Superior also has Coasters (Lake Brook Trout) that grow larger in size (propably due to more food available). I would imagine those could live to be older as well. I know the federal government is currently doing research on coasters in Lake Superior. I wonder if it's possible to find any reports or get any information from them?

I have read about coasters. A lot of biologists think they are a unique subspecies which is why they are looking at protecting them.

Did you hear the latest research results on them? Scientists have concluded even though there are separate watershed strains that become coasters they are no different genetically than the same smaller fish that stay in the streams. Apparently some head for the lake while some don't.

http://dnr.wi.gov/fish/lakesup/cbrktrout.htm

My last source which is a tribal hatchery in Bayfield Wisconsin (no longer due to quality issues and the distance I had to drive to pick them up) grew out Lake Nipigons in the hatchery for the sole purpose of planting them at various places in Lake Superior to bolster the "Coaster" population.

See my post above. As I said my last fish were planted in Lake Superior to increase the number of coasters but I had two die somewhere between age 4 and 5.

I wish it was this simple 2trackin. Faster growing fish usually don't live as long and also may have shorter life spans in slightly warmer water for the same reason. Brook trout don't have the life span of lakers either.

Have you considered feeding them less like pigs and more like a natural amount of good? Maybe 2% body weight/day instead of all they can eat. IMO a leaner less fatty, slightly slower growing fish is going to live longer.

I've definitely considered it. The trouble is it's so hard to judge how many pounds I'm feeding since I can't take samples of the fish without the risk of injuring or killing them like one can in a raceway or tank. I'm also afraid of underfeeding.

I am feeding only once a day vs. the twice a day...

With your previous experiences with the various trout you've grown, you should be reasonably able to calculate the weight gain per day from stocking to harvest. Why not create a graph over time that shows stocking weight and weight at harvest. Then you can make a WAG at current average body weight and come pretty close to what is needed based on where you are in the grow out cycle. Of course the fish don't read the book and individual aggressiveness, growth rates, and behavior will have to be considered. But overall you should be able to calculate a reasonably accurate 2% total body weight. The biggest variable for you would be number of surviving fish. Of course if you have not kept good records of past trout raising trials then this obviously will not work to well.

Records? What's that?

Those things that are called records are round black vinyl discs that have tiny grooves in them, and they make noise when spun at 33 1/3 rpm on a Victrola.

Now you're showing your age Esshup. The younger generation doesn't even know what those vinyl records are.

Bill,

As usual you are absolutely right. Unfortunately as I eluded to I'm not a records kind of guy. Oh yeah I've kept records before but they usually come up missing. I took good records of a perch harvest before and after a couple of years ago. One page is missing.

What can I say I'm artisically inclined. And as we all know artists are are sloppy and undisciplined.

Well except Leonardo DaVinci but he never finished anything.

Cecil, can you afford to maybe keep like 10 brook trout and allow them to push the envelope? If you lose them at 5 years it was only 5 fish?

Probably could but therein lies a problem. If I have five really large fish hanging around and restock with the next group which are much smaller, the smaller fish could get stressed and not grow as well -- if not eaten. Been there done that. What I really need is a second trout pond, but as Mick Jagger once said in a song, "We don't always get what we want." For you kiddies Mick was a rock star when vinyl records were in vogue.

Or I should have planted more extras to make up for mortalities.

Yeah, that was my thought... Keeping larger trout when you restock would lead to expensive fingerling trout food or the young trout as you said just not doing as well. You can never have too many ponds!

One year I didn't catch all my browns and ended up with some 5 and 6 pounders getting another year to grow. I was amazed to find those 5 and 6 pounders became 10 to 12 pounders in only one year! Before I realized I had browns that big left in the pond I added a dozen 12 inch rainbows. Only found about half that many when I drained the pond, and the ones that survived did not grow an inch and were skinny! They were too terrified to go near the feed when I threw it out! It reminded me of the snake pit in basic training. (For those of you that don't know the snake pit is where the Drill Instructors sit during dinner. There was a nice salad bar right near them that never got touched by recruits. I remember one guy that said, "I don't care I'm going to get me nice salad!" He came back with his tail between his legs!

It's amazing how big a rainbow trout a big brown trout can eat. I remember in college there was a little fly shop that had a small trout hatchery behind it along the famed Spruce Creek in central PA. The owner was a nice guy and loved to show off his private section of the creek. He'd take you down to the hatchery and scoop out a couple newly dead 10" or so rainbow trout from one of the raceways. He'd then walk down to the edge of the big hole in the creek and toss the dead rainbows into them. Within a couple seconds of those 10" rainbows hitting the water a couple MASSIVE brown trout would come up and inhale them whole. I am not sure how large those brown trout were, but I suspect if a fly fisherman hooked into one they'd almost surely break the tippet.

It would take a least an 10 pounder to inhale a 10 inch trout. The browns must have been monsters.

Ever heard of Pepacton reservoir in the Catskills? I remember reading once in Field & Stream that the big browns would be waiting like sharks when the hatchery truck dumped in the average size trout.

I no longer attempt to grow browns and brooks side by side due to the aggressiveness of the brown trout. I drain and alternate the stocking every 2 years or so. The last time I planted them together even though they started out the same size, the browns stressed the brooks enough to cause disease and mortalities. The browns ended up growing a little faster and much larger in size ultimately. The brooks did not grow as well they would have if the browns had not been in the pond.

Sounds like you need another pond!

Don't we all! I've heard fish farmers say the same thing. You can never have enough ponds!

Cecil, to get those large BRT have you considered bringing in some for the winter in a RAS, then put them in a cage in your pond next year, or is the extra growth not worth the cost?

AP,

Never considered bring trout in for the winter mainly because it would be tough to keep the water cool enough. I will do it this winter with bluegills and perch though.

Cecil:

If you leave the windows open, the temp should drop inside. I don't know how happy the other members of the household would be tho...

Hey, save on the energy bill and keep the house at a balmy 60 degrees... The trout will love it!