Just curious about how much observation has been put into watching the life cycle of Tilapia??
I have 4 tanks inside this winter and as some of you know, the main purpose was to start and observe some alternative minnow/forage species. Last fall I netted several fry Tilapia (Blue) from 3/8"-3/4" and I thought it would be a cool idea to keep them through winter and restock this spring. The aquarium I have the Tilapia in I also have a few FHM, a few GSH and a couple of Emerald shiners.
These fish are criminals.. they are now about 5-6" for males and around 3" for the females.
I've observed a couple of things.. #1, Tilapia are always hungry, #2, they will eat anything including other fish, and oh my they are suckers for Grass shrimp (PK). I put 3 YOY RES in this tank and within days the Tilapia had them killed and eaten, almost like Piranhas. They pick the bones clean and will work on the bones until gone-even while being fed high quality fish feed.
I would have never guessed these were so destructive and I'm not really sure I want to put these back in my pond.
I guess what I'm trying to say is I think they may be a stronger influence on the eco system then what I first believed.
Anybody have thoughts on this?

I stocked some larger TP early on and regretted it when they helped devour the FHM. LMB stocking failed due to lack of forage, had to put in shiners and restock bass.

No cover for FHM, and I was surprised that TP would eat other fish. Now I know better!

snipe, the year before last I did the same with a 5 Tp and 3 10 gal aquariums. Kept them through our winter here in NE Texas and released them into the pond that spring. I had no reproduction of the fish and not sure why? After reading up on them and looking for a spawn I was finding that my males would attack/bite the females, very aggressive. So much so that I felt like I needed to separate the male from the females. But, I will say that here the Tp are nice to have in my pond for forage and to reduce the Fa I see this time of year. I just placed my order for 20 lbs per acre and plan to add them April first.

Snipe,

This is a great observation and thank you for reporting. Although TP eat a lot of vegetation and can very efficiently utilize this food source .... they are considered omnivores. So they are going to eat everything your perch and lepomis are eating including their own and other small fry. They are a much stronger fish at the same length as a bluegill and will tend to outcompete them for spawning space and formulated feed.

Make no mistake, TP eat fry when they can. In fry rearing ponds, the most important practice for maximizing fry production is to remove parental fish just before the oldest fry reach a size they begin eating fry. This is generally around 3/4 of an inch and equates to about a 21 day spawn cycle. The brood-fish are removed by a large mesh seine leaving a pond full of small fry that can be grown insitu or transferred to fry grow out ponds. Just like with LMB, growing fry that are similar in size reduces cannibalism

Tiliapia are very good for BOWs where largemouth bass are a focus. IMHO opinion, they reduce recruitment of other forage species to include BG. This may be one reason many note that BG growth is good in their presence. Some say that Tilapia feed BG resulting in large BG. I am skeptical. I think it far more likely that fewer BG result in larger BG because of a reduction of intra-specie competition. For LMB greater than 16" ... tilapia can produce more forage than can BG. They can because they are omnivores that can also utilize primary production and so attain much higher standing weights.

I think a BOW where forage fish less than 2" is very important to goals .... TP would not foster these goals because they would reduce the availability of this size prey. One the other hand, if a person had a means of producing many small fry to introduce in mid-August and later, they might add a lot of prey from 3/4" to 2 1/2 "

Just wondering from what I'm reading here. If they are that aggressive would some larger tilapia cut down on a stunted crappie pond.

I don't think when tilapia are free roaming in a pond and able to feed on the wide variety of preferred foods they are not as aggressive (predatory) as noted in the initial above post by Snipe. Free roaming tilapia may eat some small fish fry but not to the point of decimating or even damaging the crop of fry. Confine tilapia into a tank and limit their feeding ability they will readily resort to attacking small fish. I think free ranging tilapia in a pond will eat organic bacteria covered bottom sediments before they will attack small fish.

It's hard for any fry to survive an aquarium setting. There is really no place for small fish to hide. The walls remove escape territory and give larger fish the upper hand. So definitely, the behavior would be muted in a pond setting where their predatory success would be reduced. I also agree that other resources are available and abundant and would comprise a large proportion of their diet.

Its all a matter of opportunity when it comes to appropriately sized invertebrates and fish prey. Tilapia are opportunists and won't just limit themselves to organics rotting on the bottom. I don't know, but I wouldn't think detritus would be preferred over things like algae, amphipods, insects, snails, and possibly even fry. In any event, Tilapia are documented to prey on their own kind in a monoculture pond setting where they are fed and there is a good bloom providing other foods. The total weight of fry consumed is small relative to these other resources but the impact is measurable and worth managing around.

Tilapia can attain high standing weights and I tend to agree with Snipe's concerns about influence on the ecosystem where they may limit resources available to other forage and consume forage intended for other fish. In a BOW where there are goals of growing lots of small forage for SMB, perch, & crappie, I do think the influence might warrant Snipe's concern.

For stunted crappie, I think you would need just a few predators that are large and do not reproduce. They need to be big enough to eat the stunted crappie, otherwise they would be competing with them. You wouldn't need to have a lot of predators, just enough to allow surviving crappie to grow to a harvestable size where your harvesting efforts serve also as predation.

Appreciate the additional comments guys, it all helps in understanding certain aspects of my somewhat limited time (and space) with these guys. I will add that over 2/3rds of my aquarium was very dense vegetation in the beginning..it was filling in to a point I was considering removing some but noticed rather early on that some of the stems were obviously more "barren".
These fish were fed optimal jr, crushed in the beginning and full size optimal jr for some time now. I throw more tetra flakes in than I would like to but it all gets whacked as soon as it's there. In-fact, I'm growing tired of picking up tilapia off of the floor every time I open the lid. Yes, it's not a pond environment but had to share what I was seeing.
If nothing else, it's interesting and is an indicator to me of the potential of what they are capable of in the right situation, and you guys may be correct in that this would never happen in a pond but I am intrigued at the notion they "may" suppress BG in the right situation. I'm sure they've been researched well beyond my capabilities.

It is my understanding tilapia will eat bottom organics to get the protein benefit of bacteria covering the bottom sediments. I think tilapia who have an enlarged gall bladder are able to efficiently digest some organic materials better than most other fish. Thus they can and will eat bottom organics when other foods are lacking. If they prefer fish fry rather than bottom organics probably - "all depends".