Tilapia Pond - Overpopulation

[DailyLunatic]

A little background.

I'm raising Tilapia in two 5x15m open air ponds, not any kind of hydroponic situation. Well water is being pumped into both ponds during daylight hours. Solar, so no additional costs for water or electricity. I do not do a full harvest on the pond and do not intend to do so. Repeat: I'm NOT going to Drain or Seine regularly and harvest. I know it is more efficient to do it that way, and that everyone else here does it. I won't. I'm too lazy and don't want to harvest for production. just me. Meaning that I use a perpetual method of taking only the larger fish, and keep the pond with mixed sizes. This allows for fresh fish throughout the year, but creates a problem...

Problem:
Fish reach sexual maturity at around 3" (12 weeks). A female lays every 4 weeks thereafter. She lays between 300 - 2000 eggs per clutch. Even if only 1% survive, it will very quickly outpace what the pond can support. Over population. [Your are here] I have many more times the number of fish the pond can sustain comfortably. I do not discourage the Egrets, or King Fishers, and actually enjoy the bird watching. I've tried ducks to keep the population under control, but wife did not care for the way they soiled the benches and walkways (they are now caged). Besides they seemed more interested in the fish food than in the actual fish.

I am looking for a self-sustaining solution. Not one of the Production Models where one drains the pond and harvests once or twice a year. Self-Sustaining

I have heard that predator fish can be introduced but that some species work better than others else they may end up taking over the pond.

This article from Langston University states:

The most practical method of reproductive control of tilapia for the small scale farmer may be through the use of predatory fish. Large mouth bass (Micropteris salmoides) is probably the most popular and is effective in controlling fry and young tilapia fingerlings. Stocking rates will vary with the stocking rate of tilapia, water clarity and size of bass. 25 to 100 bass per acre should provide adequate control. However, the fish culturist will have to fine tune the rate to local conditions.

Bluegill and green sunfish can also be effective controls on tilapia reproduction. Like the large mouth bass, the sunfish will consume the fry, however, the sunfish will also very efficiently remove the eggs. This may be more effective than control of the fry because there are no young tilapia to compete for food and also the mouth brooding of the fry by the female cannot occur. This allows her to feed on a more continuous basis and gain more weight. More research needs to be conducted on optimum stocking rates for sun fish in tilapia ponds. Five hundred per acre would be a good starting point. Again, fine tuning to local conditions by the fish culturist will be necessary.

Full article here. Discussion of Open Air Ponds begins about halfway down.

The article mentions Bass, Bluegill, and other Panfish. All North American natives. I can't find any of those here. I assume because they are not native to the area. I will keep looking.

Please understand that I will not entertain suggestions on anything Thailand considers invasive.

My first thought was Catfish, but I have learned that while they are a predatory fish, they are a little too good at it, and will eventually take over the pond.

What are suitable replacements for the Panfish in this situation, & available in this area? Prefer Bluegill sized as my ponds are only 0.02 acre ea.

What suggestions do you have for this issue? Are you aware of anything else that could work?

-sterling

 

[Cent]

A little background.

I'm raising Tilapia in two 5x15m open air ponds, not any kind of hydroponic situation. Well water is being pumped into both ponds during daylight hours. Solar, so no additional costs for water or electricity. I do not do a full harvest on the pond and do not intend to do so. Repeat: I'm NOT going to Drain or Seine regularly and harvest. I know it is more efficient to do it that way, and that everyone else here does it. I won't. I'm too lazy and don't want to harvest for production. just me. Meaning that I use a perpetual method of taking only the larger fish, and keep the pond with mixed sizes. This allows for fresh fish throughout the year, but creates a problem...

Problem:
Fish reach sexual maturity at around 3" (12 weeks). A female lays every 4 weeks thereafter. She lays between 300 - 2000 eggs per clutch. Even if only 1% survive, it will very quickly outpace what the pond can support. Over population. [Your are here] I have many more times the number of fish the pond can sustain comfortably. I do not discourage the Egrets, or King Fishers, and actually enjoy the bird watching. I've tried ducks to keep the population under control, but wife did not care for the way they soiled the benches and walkways (they are now caged). Besides they seemed more interested in the fish food than in the actual fish.

I am looking for a self-sustaining solution. Not one of the Production Models where one drains the pond and harvests once or twice a year. Self-Sustaining

I have heard that predator fish can be introduced but that some species work better than others else they may end up taking over the pond.

This article from Langston University states:

Full article here. Discussion of Open Air Ponds begins about halfway down.

The article mentions Bass, Bluegill, and other Panfish. All North American natives. I can't find any of those here. I assume because they are not native to the area. I will keep looking.

Please understand that I will not entertain suggestions on anything Thailand considers invasive.

My first thought was Catfish, but I have learned that while they are a predatory fish, they are a little too good at it, and will eventually take over the pond.

What are suitable replacements for the Panfish in this situation, & available in this area? Prefer Bluegill sized as my ponds are only 0.02 acre ea.

What suggestions do you have for this issue? Are you aware of anything else that could work?

-sterling

Add some freshwater turtles. They will eat the small fry and the fish roe.

 

[Croc]

Fish with a net every day and let your missus sell the large one's every day ... She busy and making "free" money every day = she happy = you happy !!!

 

[Cent]

Add some freshwater turtles. They will eat the small fry and the fish roe.

@DailyLunatic
I've also read that you would be smart to empty the ponds of water and fish, and let them dry out enough to kill any fish left and bacteria in the dirt etc. The sun does the job. Later refill and only populate with male tilapia fry. (How one distinguishes male from female I've no clue 555). Take the biggest and eat or sell as they grow. Add more small ones as needed. Also read that once the pond has dried you spread a certain kind of lime to the bottom and let the sun bake it into the bottom dirt (forget at the moment the exact type of lime). Supposedly helps control algae growth and keeps the PH levels stable.

Looked into doing a pond or two in/on our village lands in times past. Seemed like a lot of work for not much gain. Oh hell yeah, they'll eat the fish, but maintenance levels seemed to be more work then the village relatives wanted to do. Also suggested many years ago they add Jalapenos to their crop rotation in the family gardens by the lake. I saw there were a lot of Mexican restaurants popping up in Bangkok at the time that would be a good customer base and they'd be one of the only suppliers of fresh Jalapenos around. (I grew my own a couple times. Basically you can get two crops a year.) I would supply the seeds back then and they could grow and I'd find the customers for a small fee. They didn't listen to me of course. They didn't see the point or profit possible. Now there are a few places farming and supplying the Mex restaurants in Bangkok and Pattaya selling for a decent profit on line shipping all over. Also suggested maybe raising some turkeys along with their chickens, ducks and geese 10 years ago. When prices were not as high for turkey as they are now. They just can't see it and don't listen. LOL (Farang not know. Thai not do, or Thai do... depending on your questions asked.)

Or maybe it is the fact that once you do something here that ends up being profitable, and other Thais see this, they ALL do the same damn thing and no one can make much of a profit as they end up with a glut on the market of said item.

Ever notice in your travels the things sold on the side of the roads/highways? Notice how there will be 10 or 20 stalls all next to each other selling the same thing as all the others. All individual stalls selling the same farking thing. I asked my wife once why the hell they do not pool their product and do a sort of collective shop on the roadside selling all their wares together. As then they'd only need a couple people sitting around selling the wares while the others can then do something else to make some more money growing or making other shite to sell the same way. They can't seem to figure out how to distribute the profits equally. My wife said they just do not trust each other to not try to screw the others out of the money brought in. They could take turns sitting at the roadside selling the product, each putting in the same number of said product (honey, fruit, kilos of mushrooms, etc), and dividing the money equally among themselves. A Co-Op basically. Wasted time and energy, all sitting on the roadside in the sun and fumes selling the same damned thing. Sad they cannot even trust each other.

 

[DailyLunatic]

Add some freshwater turtles. They will eat the small fry and the fish roe.

Looked good on paper, unfortunately: "The sale and purchase of all native Thai freshwater turtle and tortoise species is illegal "

If I find one, I'll relocate it.

-sterling

@DailyLunatic
I've also read that you would be smart to empty the ponds of water and fish, and let them dry out enough to kill any fish left and bacteria in the dirt etc. The sun does the job. Later refill and only populate with male tilapia fry. (How one distinguishes male from female I've no clue 555). Take the biggest and eat or sell as they grow. Add more small ones as needed. Also read that once the pond has dried you spread a certain kind of lime to the bottom and let the sun bake it into the bottom dirt (forget at the moment the exact type of lime). Supposedly helps control algae growth and keeps the PH levels stable.

Looked into doing a pond or two in/on our village lands in times past. Seemed like a lot of work for not much gain. Oh hell yeah, they'll eat the fish, but maintenance levels seemed to be more work then the village relatives wanted to do. Also suggested many years ago they add Jalapenos to their crop rotation in the family gardens by the lake. I saw there were a lot of Mexican restaurants popping up in Bangkok at the time that would be a good customer base and they'd be one of the only suppliers of fresh Jalapenos around. (I grew my own a couple times. Basically you can get two crops a year.) I would supply the seeds back then and they could grow and I'd find the customers for a small fee. They didn't listen to me of course. They didn't see the point or profit possible. Now there are a few places farming and supplying the Mex restaurants in Bangkok and Pattaya selling for a decent profit on line shipping all over. Also suggested maybe raising some turkeys along with their chickens, ducks and geese 10 years ago. When prices were not as high for turkey as they are now. They just can't see it and don't listen. LOL (Farang not know. Thai not do, or Thai do... depending on your questions asked.)

Or maybe it is the fact that once you do something here that ends up being profitable, and other Thais see this, they ALL do the same damn thing and no one can make much of a profit as they end up with a glut on the market of said item.

Ever notice in your travels the things sold on the side of the roads/highways? Notice how there will be 10 or 20 stalls all next to each other selling the same thing as all the others. All individual stalls selling the same farking thing. I asked my wife once why the hell they do not pool their product and do a sort of collective shop on the roadside selling all their wares together. As then they'd only need a couple people sitting around selling the wares while the others can then do something else to make some more money growing or making other shite to sell the same way. They can't seem to figure out how to distribute the profits equally. My wife said they just do not trust each other to not try to screw the others out of the money brought in. They could take turns sitting at the roadside selling the product, each putting in the same number of said product (honey, fruit, kilos of mushrooms, etc), and dividing the money equally among themselves. A Co-Op basically. Wasted time and energy, all sitting on the roadside in the sun and fumes selling the same damned thing. Sad they cannot even trust each other.

You get all male by introducing them to drugs that transition them from female to male early. Excellent if you are wanting production. NOT excellent if you are wanting a perpetual eco system.

Think of my goal as similar to that of a home prepper. I want this to work, year, after year, without my having to introduce anything to it but food. Not to sell or to make large harvests.

I've defiantly run into the 'Thais don't do it that way' as well as a few variants. I broke down and said gently, then in increasing firmness, "I don't care! Dig the ditch deeper, and lay the septic field lines like I tell you." I got tired of the stink.

-sterling

 

[Cent]

Looked good on paper, unfortunately: "The sale and purchase of all native Thai freshwater turtle and tortoise species is illegal "

If I find one, I'll relocate it.

-sterling


You get all male by introducing them to drugs that transition them from female to male early. Excellent if you are wanting production. NOT excellent if you are wanting a perpetual eco system.

Think of my goal as similar to that of a home prepper. I want this to work, year, after year, without my having to introduce anything to it but food. Not to sell or to make large harvests.

I've defiantly run into the 'Thais don't do it that way' as well as a few variants. I broke down and said gently, then in increasing firmness, "I don't care! Dig the ditch deeper, and lay the septic field lines like I tell you." I got tired of the stink.

-sterling

Show some of the young kids what you want and pay them to go catch a few turtles for you. That law is about the critter shops that buy and sell. Hell, the Thais in the villages will catch and eat them. You're just repurposing the turtles to a safe area on your land with orders to all and sundry not to eat your turtles.

 

[Rice]

I see turtles on the road from time to time. I always stop and rescue them and take them to my pond.

 

[Cent]

I see turtles on the road from time to time. I always stop and rescue them and take them to my pond.

I see Thais stopping and grabbing the turtle in the street. Always wonder if they are rescuing it or taking it home to eat for supper. Spicy turtle soup.

 

[Merlin]

Turtles, or tao in Thai, are considered to be lucky here. They have a reputation for bringing good luck to those who see them Few people here will eat them - presumably those who aren't superstitious!

 

[Cent]

Turtles, or tao in Thai, are considered to be lucky here. They have a reputation for bringing good luck to those who see them Few people here will eat them - presumably those who aren't superstitious!

Or hungry.

 

[Cent]

Or hungry.

Yes, I've seen a lot of Wats/temples with ponds that stock the large pig nosed turtles, for luck I assume. Was at one place and there were nearly a hundred turtles sunning themselves on the temple pond steps.