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Possumpoint

Hatchery Raise Trout

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Old Hat,

 

Maybe some hatcheries are not 'closed systems' but many trout are raised in concrete runs, some of which are in enclosed metal or fiberglass sheds. Aside from the occasional fly or other bug that finds his way into one of these runs, I don't think there is an entire ecosystem complete with annelids and insect hatches going on under most hatchery conditions.

 

 

Best regards,

 

Cody

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Old Hat,

 

Maybe some hatcheries are not 'closed systems' but many trout are raised in concrete runs, some of which are in enclosed metal or fiberglass sheds. Aside from the occasional fly or other bug that finds his way into one of these runs, I don't think there is an entire ecosystem complete with annelids and insect hatches going on under most hatchery conditions.

 

 

Best regards,

 

Cody

 

As a fisheries biologist with some background in aquaculture, I would tell you, if you find a hatchery that is raising fish for release into a natural water system and it is a closed hatchery system, contact the police or your congressman. ;) It is either illegal or or a huge waste of tax dollars. Also, I did not mention an entire ecosystem at work only that the fish are exposed to most food stuff from the natural environment. I know of closed systems used for raising fish for egg production, food, and research but I would be extremely surprised if fish bound for delivery into a natural system never were in an open system. I don't know of any. I could be wrong, it may be done somewhere, but it is definitely far from the norm.

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Up here at our greatest trout lake Strawberry, They have a hatchery on site open to the lake, they are fed pellets and they are able to eat bugs as they please. For the trout that do not go out into the lake on their own, they get loaded up in "water trucks" and get delivered to the different parts of the lake and elsewhere (yes these fish get hosed out). These fish have a timed feeder, of course they eat bugs in between feedings, but after they get relocated they are still stuck on their feeding schedule. The DNR pulls fish after feedings for transport to most our trout ponds lakes and streams, being that the Wasatch front is not even the size of Houston the fish are still full when they are released, thus they wont eat after stocking.

 

I'll tell you this though PFC is deadly even weeks after after a stock as long as its when they are supposed to be fed.

Back in my bait days we would go out with actual fish pellets during feeding time and bring in a haul.

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Old Hat,

 

Maybe some hatcheries are not 'closed systems' but many trout are raised in concrete runs, some of which are in enclosed metal or fiberglass sheds. Aside from the occasional fly or other bug that finds his way into one of these runs, I don't think there is an entire ecosystem complete with annelids and insect hatches going on under most hatchery conditions.

 

 

Best regards,

 

Cody

 

As a fisheries biologist with some background in aquaculture, I would tell you, if you find a hatchery that is raising fish for release into a natural water system and it is a closed system, contact the police or your congressman. It is either illegal or or a huge waste of tax dollars. Also, I did not mention an entire ecosystem at work only that the fish are exposed to most food stuff from the natural environment. I know of closed systems used for raising fish for egg production, food, and research but I would be extremely surprised if fish bound for delivery into a natural system never were in an open system. I don't know of any. I could be wrong, it may be done somewhere, but it is definitely far from the norm.

 

 

Old Hat,

 

 

I am aware of your background in fisheries, so I don't discount your opinion. I'm sure you have had experience in open system hatcheries since they do exist in some areas.

 

I also have a degree in Aquatics Sciences, with an emphasis on salmonids, and I have had my hand in trout production at hatcheries in Kentucky, Missouri and South Dakota. I am currently involved in a trout growth rate study which involves dissecting hatchery trout at different stages of development and examining gut content. I tell you this only to make you aware of my first hand experience in hatcheries. There are as you say, some hatcheries which may have open runs, but many State run hatcheries I have had experience with do in fact keep the majority of the fingerlings to be released in runs enclosed in sheds. This protects trout from the elements in colder climates and also protects agains predation from birds, minks, etc. In my experience, runs that are not enclosed are still kept clean, and do not allow natural food sources to be a common occurance as might be believed. This is not unusual at all and I don't believe it is a case for national alarm as you say. I don't wish this to become some huge forum debate, but I would like the information provided to remain factual and relevent.

 

Best regards,

 

Cody

 

 

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Maybe an East/West thing. It is exactly the far opposite in my experience. No debate, just different experiences and education I suppose. As I said contact your Congressman. $$$$$. ;) The only conclusion I can draw from this discussion is neither one of us knows what we're talking about. Sounds a bit like the gentlemen in Washington DC. All in fun.

 

Possumpoint - truthful answer to your original post ...There are too many variables. No body knows for sure.

 

 

On the lighter side...one of my favorite quotes is by the late Gary Lafontaine, talking about sneaking up on fish streamside "Fish always know you are there, hell, even a hatchery fish knows you are there, it's just that 're glad to see you."

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Devin:

 

If you know what to do, I bet you can catch those fish on PFC flies, regardless of how close the time is to their 'feeding time'. All one has to do is simulate the splatter of the pellets on the water surface with your fly. Make fixed-line-length casts as fast as you can to a small area, making sure that the fly hits the water with a commotion. I have yet to see a chow-fed fish that won't respond to this 'chumming' tactic.

 

perchjerker

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I will prempt this by saying that I am working towards a PHD in aquaculture right now and will be in fact raising rainbow trout for my dissertation work. My work is on rainbow trout nutrition (IE the feeds we give them), though my focus is on fish primarily raised for food purposes. This is mostly my opinion based on what I have read, studied and experienced myself.

 

There are quite a variety of ways trout are reared. It does all depend on location. Some people are lucky enough to have a spring on their farm and use that as a water supply. They simply direct the water through tanks (typically after degasing as spring water can be saturated in nitrogen) and flow it through. Then hopefully it goes through some sort of filtration before running off into a creek, river or lake. Other folks may raise them in large ponds with less flow but good cold water and lots of aeration. Most hatchery systems are flow through systems with research systems like mine being recirculation. A closed system is beneficial in that it can be controlled for water temperature and quality and is usually free of pathogens. A surface water operation (IE taking water from a lake or stream) should have some kind of prefiltration if possible. Maybe solid and usually some sort of UV filtration to remove pathogens. If they use springs, wells or aquifers its usually not a problem. Ive never heard of a closed system (Im assuming you mean a intensive recirc system) being illegal in any way. They do require more input in terms of money and resources but also produce a greater output.

 

I believe most trout (at least everywhere Ive fished) are raised and released by government agencies so there wont be any legal issues there. The ones raised by private folks are used for private stockings or to supplement the government stockings and then in that case the government folks Im sure pick ones they know raise them right. In the Eastern US there are also some shipping rules to make sure fish are pathogen free if they are going across state lines (Im sure there may be concerns in the west too). I am trying to get trout from Missouri to Illinois right now and am waiting on some tests to get done so the dealer can get a permit that says the fish are VHS free.

 

As far as hatchery trout feeding... again it probably depends on how they were raised and transported. There will be some shock probably and they may be a bit hook shy at first. But I have caught freshly released trout before using a variety of flies and lures. They may take some time to adapt but there is a lot of natural instinct there too. As a side note I have been involved in raising hybrid stripped bass in ponds for a few years. We have food size fish (1-2 lbs) in ponds that have only ever eaten pellets. However, being in outdoor ponds there are some natural inputs like insects and what not that Im sure these fish have taken to eating if they feel like it. I wanted to remove a few for myself to eat before the harvest and went out to throw some flies at them. They were nailing them as soon as it hit the water. So I think with a lot of fish if they have been raised and transported properly and are healthy their natural instinct to hit something that looks like food (insect, fish whatever) will take over pretty quickly. Unless of course the fish is just a moron. Most of the evidence of this is anecdotal though and just reading through the thread there is a wide variety of experiences. But if the fish didnt eventually hit lures and/or flies after being stocked then the stocking programs would not be the success that most of them seem to be.

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Thanks for the info. The illegal comment was a poor attempt at humor. We do have problems with "private closed system hatcheries" (think hidden distillery or pot crop) here raising salmonids and other non-native fish for personal battles to "help" restore sporting populations.

 

However, closed system=greater output, would be a matter of how you define output. Just the number of fish leaving the hatchery for distribution or post release survival available to the sportsman or supposed supplement to the native population. Simply, and I understand now there are definitely two sides to the fence, ( I hadn't realized the extend of closed system use by our government agencies, I honestly thought the method was "old school" and mostly reserved for research purposes) I would contend there is more bang for the buck in raising fish ( species might make a difference as well) for resource use when you take into account acclimation, cost of raising a fish to a specific age best suited to post release survival, predator response and on and on with a number of variables in an open system. This is why I was questioning the cost or rearing to available catch ratio. I would like to see some comparative research on the two methods. Just for interest sake.

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Thanks for the info. The illegal comment was a poor attempt at humor. We do have problems with "private closed system hatcheries" (think hidden distillery or pot crop) here raising salmonids and other non-native fish for personal battles to "help" restore sporting populations.

 

However, closed system=greater output, would be a matter of how you define output. Just the number of fish leaving the hatchery for distribution or post release survival available to the sportsman or supposed supplement to the native population. Simply, and I understand now there are definitely two sides to the fence, ( I hadn't realized the extend of closed system use by our government agencies, I honestly thought the method was "old school" and mostly reserved for research purposes) I would contend there is more bang for the buck in raising fish ( species might make a difference as well) for resource use when you take into account acclimation, cost of raising a fish to a specific age best suited to post release survival, predator response and on and on with a number of variables in an open system. This is why I was questioning the cost or rearing to available catch ratio. I would like to see some comparative research on the two methods. Just for interest sake.

 

In terms of food fish output is defined as total weight of fish produced typcially. In a stock enhancement situation I would say its #'s. A lot of research has been done on some of the stuff you are talking about. I am aware of some work in Iowa and maybe South Dakota looking at stocking size of walleye and survival to future years. Selective breeeding is definetly happening with more robust fish being used in hopes of producing a fish that will survive better. I would say the cost:catch ratio is good (it can always be better Im sure). Mostly because at least in the East many of the trout/salmon you catch originated in hatcheries. Technology has allowed us to produce more fish at cheaper costs. I can get trout and/or salmon eggs shipped to me almost year round if I want and raise them in fairly simple systems that cost little to operate (though feed costs and energy costs can change that...but Im working on the feed issue).

 

You use the words open system and closed system. Im assuming for open you mean something with flow through water from a surface source that may allow for some external inputs? And for closed you are talking using like a well or something and recirculating the water through filtration? I really dont know. The terms we use typcially are extensive and intensive. And that is on a wide ranging scale. The most extensive culture would be a guy who has a pond, throws some fish in (at normal or low density) and doesnt do anything else to it ever until he harvests the fish. No feed, no fertilizer, no aeriation. Then you start to add that kind of stuff and you begin being more intensive. The most intensive would be the recirculation systems with lots of filtration to control water quality, heaters and chillers for temp, all food provided in the form of pelleted feeds, lots of supplemental aeration and stocking densities that would be considered quite high (though not a problem due to the control we would have).

 

I think for the most part most stocking programs take a lot of things in to account. I too would like to see some better acclimation to the new environment first but sometimes they have to just get the fish in. Rules and regulations limit the use of pretty much all sedatives for fish when transporting. This means a long haul is stressful on the fish and having them sit in the truck even longer to acclimate may be more risky than just releasing them. But Ive talked and worked with hatchery folk who have done a lot of hauling and they learn tricks to keep fish alive and well. I contend that most hatchery fish adjust to their new enivronments quite well. Thats not to say we cant make it better and have more success.

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