Pond Boss Forums MANAGING AN EXISTING POND Evaluating and adjusting fish populations put, grow and take management

This is a type of fishery that we mention frequently but really haven’t talked about in any type of detail.

In our small lakes, catfish, HSB, trout and sterile grass carp are almost always managed like this. In the north, walleyes are stocked in huge numbers for this type of fishery. I’m guessing that almost every state/province has fish hatcheries providing babies for just this reason.

This is the type of fishery we have in our 4-acre lake. Our lake is essentially a huge aquarium. We provide food in the form of pellets and baby fish, frogs etc. After that, it is a matter of stocking species that can survive together, the same as a person would do with an aquarium.

Almost all of our discussions have been about managing reproducing populations of fish such as LMB/BG. Even with CC, HSB and sterile grass carp, there has been little discussion about restocking rates. We buy fish by numbers and size. Therefore, those are the types of guidelines I’m looking for.

I see a lot of potential for this type of fishery, especially in smaller lakes. There are so many variables but to set some guidelines to help people, let’s make some basic assumptions. We want a general fishery for the kids, grandkids etc. Except for the forage species, let’s assume that everything is released. What we are looking for is natural mortality. Restocking will be fish removed plus natural mortality. There is no one right answer but let’s try and get a range.

Let’s assume a 1-acre lake with forage of pellets and/or small fish. For sake of argument, let’s assume that the LMB do NOT reproduce so that we can get figures for them also. Let’s also assume an existing population. Remember that some species live much longer than others. For each species, lets try and come up with the following numbers. Typical numbers of adult fish per acre, average mortality per year, size needed for restocking, number needed per year and some general cost per individual.

LMB:
SMB:
CC:
HSB:
Sterile grass carp:
Walleye:
HBG:
Any other:

Any other information would be greatly appreciated.

I'll take the HSB question. For wipers, or hybrid striped bass I've had a great catch and release fishery that was at 400 individuals per acre. The fish were easy to catch and healthy until the "big crash". If I were to do it again (which I am) I would stick to about 20% in numbers which would be about 80 fish in a one acre pond. Average mortality per year for wipers is pretty low, especially for younger fish. Natural mortality would be less than 10%, but if you had regular handling by anglers that might go to 25% if you were using artificials, and 40% if you were using live bait. Wipers swallow the hook fast! Size needed for restocking, in the presence of other top line predators would be a minimum of around 8 inches. These fish can be acquired for about $1.25 each, plus shipping, so you could assume an annual restocking cost of 25 bucks plus shipping for 20 fish.

Norm :

That is a huge task but I am game to help with it. I think we need to start with getting Dave Willis involved as this is a topic for a paper by a PhD candidate or AFS or a chart for PB. We need to have an organized method outlined or we will get really skewed results (different info parameters). Example hooking morts. are all over the place based on water temps. ,time of year reflected in fish K and type of fishery etc.

It all depends. For the grass carp are there weeds for them to eat or are they surviving primarily on pellets? Are we stocking them for weed control or just to have some big fish to occassionally catch as a surprise?.

Are you going to monitor the condition factors of any of these fish? Is it a concern? Are you looking for decent growth or just normal survival?.

Yes, I understand how big of a project this is. However, we know many bits and pieces already. Let's just start with parts that we already have information about. Let's just do CC and HSB first. We have lots of information about initial stocking rates so let's move on to restocking rates. In both cases, let's assume a 1-acre existing LMB/BG lake.

Channel Catfish: what would be normal stocking rates? Restocking is so common that we must have lots of info about that.

HSB: we are just getting into them but they have been in common use for years. There should be lots of studies about restocking rates. State fisheries must have this info.

Can we get info about these two species first?

Norm/Ewest: There is indeed much information on these topics floating around the fisheries profession. Summaries and review papers are always extremely valuable. Having said that, I think we may have one specific challenge. Most of the published literature and state agency reports will be for larger, public waters. These waters tend not to be as intensively managed as some of the ponds managed by Forum Pondmeisters. Eric, you may very well know how much work is still being done on pond management by southern schools such as Mississippi State, Auburn, or Texas A&M. I have a sense that not much is currently being done. Certainly, I have a strong sense from my past several years on this Forum that the innovative work so commonly discussed here is not occuring in research efforts. BOB LUSK -- could we get you to comment on this? You're closer to the situation than me.

From my own perspective, I'm primarily educating graduate students through research on large, public water systems. ALL (every single bit!) of our pond work is "fun" work, and often done only out of personal interest or for my graduate advanced fisheries management course (every other fall semester). So, when Ewest suggests putting a PhD student on a review project such as this (which incidentally would be GREAT for his or her education), then I have to factor in the time. Their education, their salary, their equipment costs, their vehicle costs, their travel costs, all are paid by the funding agency. Thus, we first have to meet contractual obligations, and then fill in the "spare" time with fun projects from good ideas such as this.

It seems that I have moved away from the primary topic, but I thought this should all be explained. Our fisheries profession still looks at small ponds primarily as bass-bluegills, well maybe some channel cats through in, and managed for either big bass or big panfish. That's obviously still ok in many situations, but the truly interested pondmeisters want more.

For now, I'd like to hear Bob's thoughts on the matter. Unless he changes my mind, the best information on the "special" types of put, grow and take stockings (hybrid stripers in half-acre ponds, male-only bluegill ponds, female only yellow perch ponds) may actually come from this forum. Certainly, we could supplement with information from public waters on more basic questions.

Yes Bob Lusk needs to provide some input here (obvious hint placed in a prominent location).

I think Norm assumes more information has been published than actually exists on this topic. His situation for a fishery is very unique. As far as I have seen in the literatue, harvest is a big or primarily or underlying goal of the research topics, few look at a fishery on just a purely Put and Release basis. "Everyone" esp public semi-public waters are mainly interested in how to manage the fishery to maintain a harvest rate of some type.

I think what Norm needs to be asking are, what are the expected life spans of the species that are in his pond (conditions) and how often do the fish need replentished or restocked based on expected life span. I think every answer he gets will be a big guess for this topic because there are numerous variables / unknowns in each pond situation that will affect the life span of each type of fish. Catch and release alone by novice fish handlers is a big unknown, plus length of time the fish is out of the water, amount of slime removal, ambient temps during capture, and amount of food supplies for a healthy recovery are all unknowns. I would think that tossing a fish back into the water from the height of a covered bridge (high dock) alone would be stressful considering a fish is essentially weightless its entire life and just removing it from the water and exposing the internal workings to full gravity is probably somewhat stressful in itself. I think the best Norm can expect from us, is an average or reasonable time frame or schedule for restocking of each species.

Ideally a routine shocking survey / or net samping would provide the best picture of what species are still present and at what relative numbers. Obviously these are just my opinions or 2 cents worth on this topic. I do now realize after numerous years in this business that most pondowners including myself, think they have way more fish in the pond than actually exists there. A recent pond draining, again, proved that to me. "We never see any dead ones", is what I frequently hear. "We put all those fish in there; what happened to them!"

Bill, Dave and everyone else, I'm not looking for this information for myself. Please don't let my particular situation influence any answers. Rather, my hope is to provide some guidelines on this type of fishery.

Let's start with CC. A common small lake fishery is LMB/BG and CC. Has anyone has used this type of combination? If so, at what size did you harvest fish? How many fish did you restock per acre and at what size? Did you restock every year, every other year? Any other details would be appreciated.

This is a chance for lots of people to contribute to our knowledge of restocking Channel Catfish.

HSB have been introduced to us by Bruce Condello. Many members have said that they hope to try them in their lakes. Does anyone have any experience in restocking? Has anyone thought ahead about restocking rates?

Are any of the studies about HSB in larger lakes applicable to us? Can any of this info be scaled down to the level of our lakes?

Norm:

I don't have long term, restocking experience (yet), but IMO CC are best harvested between 1.5 and 4 lbs. Over 4 lbs, the fillets get hard to remove and have too much thickness variation for cooking; you would probably have to go to the "catfish steak" technique I saw my Grandpa use a couple of times.

If I were going for a balanced BG-CC-LMB fishery (equally interested in all 3), I would try to keep about 50 CC/acre in the water. And I would restock CC around 12" long, if available. Restocking rates/intervals would depend upon harvest (and therefore CC growth and whether or not they were fed).

Hope this helps.

Geez, guys. I'm not sure I completely understand the question. Is the question how many fish can be raised in a single species put and take pond situation? Or, is the question which combinations of these different fish work well together and how many of each can you grow? Or, is the question how well will all these species of fish work in one pond? And then, recruitment comes only from restocking, based on what we might assume 'natural' mortality to be, basing that concept on old age?

To understand how to answer all of these questions, we first need to understand a pond's ability to produce, then sustain a population of fish, artificially propped up with pelleted fish food.

Here's what I have learned through experience...watching, thinking, building, draining, measuring and weighing lots and lots of fish. Oh yeah, and reading, too.

One variable will be age. Different fish have different age limits, based on geography, habitat and food chain. For example, a native northern strain largemouth bass in Texas can live to 8 years of age, sometimes 10, but one fish in particular, in Illinois, as I recall, was documented to live to 22. For discussion, let's assume each fish has 'x' number of heartbeats, then passes on to the big skillet in the sky. Relatively speaking, the number of heartbeats is an environmental consequence, since fish are cold blooded (like a handful of our distinguished colleagues on this website)

So, my take on the individual fish are as follows...

LMB-Largemouth bass. Two key thoughts here. LMB are instinctively predatory, so a pond's carrying capacity is directly related to the amount of natural food available. Typically, a one acre pond can support 50-75 pounds of LMB, with strong support from bluegill. The second thought is concerning LMB conditioned to feed. I know the fish farmer who started this trend, and they claim 4-5,000 pounds per acre. But, they can exchange water, feed the fish religiously, and use the most expensive feed on the market. But, for John Q. Pondmeister, 300-400 pounds per acre is probably more reasonable. The limiting factor is how complete the feed is. Keep in mind bass on feed are typically obese, and their lifespans are shorter. How many fish to stock? Depends how big you want them to become. In the first example, stock 50 fingerlings, or as few as 20 advanced intermediate size fish to begin. For the second, stock as many as 100-200 fish per acre. Expect pellet trained bass to convert about 3 to 1. Bass which eat live food exclusively convert around 10-1.

SMB-Smallmouth bass. SMB can be maintained at similar rates as largemouth bass, when stocked as the primary predator. Standing crops are similar to LMB. Habitat issues are considerably different for SMB compared to LMB and have a direct impact on the pond's ability to grow and sustain the population. As goes the pond, so goes SMB. Not as much for LMB. If feed trained, expect 3 to 1, maybe a bit less.

HSB-Hybrid Striped Bass. HSB are 'patrol' type eaters, opting to stay on the move, in deeper, open water. But, an average pond owner can expect to grow as much as 400-600 pounds of HSB in a one acre pond, all things being even for the 'right' habitat. Numbers of fish? Again, depends on the size. I would go with 100-200 in a single species stocking, dependant of fish food. An old hybrid striper in the south is 8-10 years. I honestly don't know how long they will live. Expect 2 or 3 to 1 as feed conversion rates.

CC-Channel catfish. These are the easy guys. We can easily stock as many as 100 in a one acre pond, not feed them, and they will thrive and grow to 2-4 pounds each. But, feed them, and you can stock up to 1,000 and expect them to make it to one pound apiece, when productivity is maxed. When a pond pushes to 1,000 pounds of channel cats, expect nature to push back. A 15 year old channel cat, in the south, is old. They convert fish food near 2 to 1.

Sterile Grass Carp. These fish are less known, because no one raises them for a put and take fish. They are used to control excess vegetation. But, they convert wet weight of food somewhere in the range of 40 to 1. I've watched grass carp go from one to seven pounds in a Texas lake from November to July. But, how many can a pond support? These fish are quite different. They eat methodically, all day long, and gain weight fast. But, once the food supply goes away, they drop that weight almost as fast. I have seen grass carp grow from 35 pounds to 12 in less than six months. So, a put and take pond of grass carp could literally see 20 fish swell to 700-800 pounds totally, then shrink and maintain at 300. Again, feeding alters the equation, but not much with grass carp, unless you plan to add lots of grass clippings, hay or bibb lettuce. These creatures normally live to 13-14 years in warmer climates.

Walleye-these top line predator fish fight to make a life. They eat other fish, including each other, often, without conscience. If a one acre pond can support 30-50 adult walleye, give yourself a big pat on the back. But, to get them as big as six or seven pounds, budget 8-10 years and lots of gallons of northern fathead minnows. While walleye are predators, their habits are such that fish as bluegill aren't efficient forage fish. Walleye would rather live deep, in structure. Bluegill choose shallow, in dense cover. Walleye convert live food at the rate of 8-12 pounds of fish to one pound of walleye.

HBG-Hybrid Bluegill. Lots of debate about this fish. As a target, singular species, a one acre pond can easily support 500-600 pounds. If they weigh an average of half a pound, stock 1,000-1,200. Want bigger? Stock fewer. Pushing the limit? A pond could grow as many as 1,000 pounds of HSB, but water quality issues would quickly follow. These guys convert fish food at less than 2 to 1. They live as long as 6-8 years.

Now, let's shift gears. Combining these fish completely changes the equations. Think about how each species lives, what they eat, their behavior patterns, habitat requirements and you will see what I mean. Alone, each fish might thrive in a one acre pond. But, put them together, and it's like the Pittsburgh Steelers lining up against the Nebraska Cornhuskers as they tease your favorite high school football team. In the meantime, HSB pirates are raiding the fridge in the middle of the pond, while LMB fight for space with walleye, who have an advantage over smallmouth bass, while spinach eating Popeye-sailor man grass carp are vegging out. Over there, in shallow water, laughing and munching, the HBG dart in and out, eating while trying not to be eaten. Then, spread an even helping of "productivity" around, and soon, you see fewer fish of each type as they thrive, while the other decline due to high competition, room rent and a run on the grocery stores.

Throw in one other factoid. Different individuals within each species exhibit different behavior. Some are aggressive, some are passive. Some grow fast, some grow slowly, just like all other creatures.

Here's the bottom line, from my beady little brain. A one acre pond, fed moderate amounts of fish food, will safely sustain 600-800 pounds of game fish. We can pick the combinations, but Mother Nature will choose the success, based on habitat, size distribution, growth rates, aggressiveness and luck of the predatory draw. (If a fish is eaten, is it our fault?)

Regarding the restocking question, the only way to know is to figure it out by regular monitoring of individual fish and their body condition. If regular samples of fish determine the little gems are overweight, the pond can support more. Stock a few. But, if the little toots are bit on the runway model side of size, there are too many, or not quite enough little food nuggets.

Now, what was the question?

WOW!! Nice Job Bob. I didn't know what to do with this thread...was just as confused as you as to what we were trying to get at really. I like to see the "fish farmers" point of view. Good post! By the way, why are we both up after midnight? Must be something in the air...or cabin-fever.

I wish my brain was little and beady!
Great post oh pond master!

Bruce- I was trying to remember who had the HSB super pond that crashed. That was a great pond story. What is the average water temperature there in the summer? When are you going to start another one?

Hey, PFF!

Yes, I will always be known as the pilot of the big crash. :rolleyes: :p (this defies graemlinology)!

I've got the same pond up and running again, but at about 15% the density. I didn't go down with the ship last time and I'm so addicted to bluegill, redears and yellow perch that I'll stick with them for awhile. Ha!

If Bob Lusk is going to put out that much good information whenever he's unclear on a question, let's ask unclear questions more often!

Here's a question I hope is clear. 1 acre pond, existing LMB (slightly overcrowded for bream control), BG, RES, and GShiner populations. About 20 middle-sized (5-7 lbs) CC. How many HSB (assume 10" - 12" HSB are available to avoid initial LMB predation) can be stocked if the owner is going to support with middling level feeding (say up to 10 lbs Purina Aquamax a day, 5-6 days a week)?

I (yes, this is a truly important question because it involves ME) am thinking that 30 HSB would be OK. But would 50 definitely be too many? I'm in no hurry to qualify as an aquaculturist by killing all those fish at once.

I think thirty is a great number, given the fact that it would be pretty easy to cull down to fifteen or twenty if they were dominating your feeding horizon.

Thank you all, especially Bob for this great post. Does everyone understand the significance of Dave Willis and Bill Cody's post? There just isn't much research out there about our small lakes! There might be few, if any, follow up studies on initial stockings. We have to produce this information ourselves.

We think that Bob Lusk, Dave Willis, Bill Cody, Greg Grimes and others can spoon feed us all of the answers. And yes, they have years of expert experience and are invaluable resources. But all of us are the ones that have to give them more data for them to help us.

So, I would like to narrow this subject down even more. Let's just deal with channel catfish for now. Everyone, if you have stocked CC, please provide the following information.

Year stocked:
Size of lake:
Number of CC stocked:
Approximate number of CC removed to eat:
Approximate size of CC removed:
Any restocking and if so, number, size and years:
CC restocking plans:
Will you just let CC die out?

There are a number of things these replies will tell us. I'm wondering if, in fact, most people that initially stock CC don't ever restock. All of this is extremely important for us to know. The more replies we can get, the more this will tell us.

I'm involved in management of several nice ponds right now, so I'll give them example of Bill Westlund's pond near Lincoln, NE

Year stocked: 1999 (I think...I'll check)
Size of Lake: 2.5 acres
Number of CC stocked: 100
Approximate number of CC removed to eat: 80 so far
Approximate size of CC removed: 24 inches
Restocking plans: Not currently. Landowner likes LMB, BG and BC, and feels that the CC were taking almost all of the feed and although he enjoys them, he wants them to play a smaller roll for now.
Will he let them die out?: He may consider restocking 20 or so in the next two to three years.

Year stocked: 1986 & 2005
Size of lake: 9.9 Acres
Number of CC stocked: 200-1986 100-2005
Approximate number of CC removed to eat: 30
Approximate size of CC removed: 27-30"
Any restocking and if so, number, size and years:
CC restocking plans: Fall of 2005-100 CC restocked 8-10" in size
Will you just let CC die out? No, but have not heard of a single CC being caught for 5 years now, probably due to the aquatic vegetation making fishing for CC very tough.

Note: some evidence of "minor" successfull CC reproduction in the pond has been seen twice in the last 20 years.

SHORTY

Hi Norm,

Stocked May 2003
0.9 acre pond
100 CC stocked, nominally 6" to 9"
To date, 48 CC have been removed to eat.
Size Break down:
14" - 3
15" - 8
16" - 4
17" - 9
18" - 4
19" - 4
20" - 6
21" - 5
22" - 2
23" - 2
24" - 1
No restocking yet.
CC plans:
My next batch of put, feed, and harvest fish are going to be HSB. I want to reduce the CC numbers down to 20 or so before I put the HSB in. But (longterm) I want to have a couple of monster CC in the pond to occasionally trash fishing tackle, and I like eating CC well enough that I will restock at some time in the future, probably from 25 to 50 9" to 12".

Year stocked: 1989
Size of lake: 0.75 ac
Number of CC stocked: 20
Approximate number of CC removed to eat: 6
Approximate size of CC removed: 20"-26", by 1998 grew to 30".
Any restocking and if so, number, size and years: none, decided catfish were a nuisance, pellet hogs, discourage other fish from feeding
CC restocking plans: none, other fish better for needs
Will you just let CC die out? Drained pond for rebuilding. Glad to have catfish out.

Sorry, Norm. My input here is pointless, but that hasn't stopped me before.

Year Stocked: 2004
Size of Lake: 6.5 acres
Number of CC Stocked: (10)at 10-12" each.
Comments: Have never seen them since, although, back then, any fish could freely swim in and out of my pond.

Restocking: Fall 2005
Number of CC Stocked: (12) at 12", and (3) Albinos at about 26" long each. Now Fish cannot leave the pond.

While I don't care for the look of albino fish, I wanted to be able to see these fish in my pond from time to time. It's going to be hard to miss those three albinos.

I don't really see eating any of them, so they may live out the life span or die due to catch & release mortality. Due to many other predators, I doubt they will have recruitment.

I don't ever see putting in more than (20) in any single future stocking. I wouldn't even add any for at least two years now.

Sunil, all of this info is important. Thank you all for your input.

A number of people have asked us for help with different measurements on our lakes. The response has always been poor. It seems to me that we have reached some sort of critical mass on this forum that could make surveys more useful.

My thinking is that we need follow up surveys of our lakes. We can't wait for the government to do everything for us. Maybe I've been asking the wrong questions.

Do we need follow up info on our lakes?
If so, what info do we need?
Any particular info that someone would want?

Dave Willis, Bill Cody, Bob Lusk and others, is there some type of data that you would like to see?

If we decide to do this, I volunteer to keep and complile the info.

Year Stocked: 1999
Size of Lake: 1 acre
Number of CC stocked: 100
Removed to eat: 5 (unknown how many taken by people sneaking in)
Size: 5-7 pounds this last summer
Comment: Had a DO crash this past fall. Don't know how many CC died. I didn't get up there until 2 weeks after it happened. Neighbor said he saw some catfish. I saw dead bluegill, bass, and grass carp. I didn't see any CC. Will restock if numbers seem to be down quite a bit this summer.

Year stocked: Oct. 2001

Size of lake: 2 acre

Number of CC stocked: Unknown – guess 200+

Approximate number of CC removed to eat – (or give to neighbors) :100+

Approximate size of CC removed: 2 to 8 lbs

Any restocking and if so, number, size and years: NO

CC restocking plans: None - CC will be replaced by adult HSB, now that Overton Fisheries has made them available at fair prices.

Will you just let CC die out? YES - They have become pests – muddy the water – eat all the feed, but fun to catch on pellet flies – but – not as much fun as HSB.

George Glazener
N.E. Texas ¼ and 2 acre ponds

I will add my pond info later today. It may take a while. However in the meantime I don't think Norm would want the thread to flounder so I think Norm would be ok with us moving forward. By now we have gathered some good info on CC. I could not add much there nor can I on HSB which is where Norm wanted to go next.

So if any of you grand growers of HSB could help us out please tell us what you know about a put and take pond containing HSB as per Norm's request. Thanks for any data.