Pond Boss Forums INTRO Questions & Observations Fatheads and Gams, 1 observation & 1 question

1. I shutdown the 100 gallon Po'Boy RAS in my basement 2 months ago when I moved the 20 RES from it into my new pond. Rather than pick it up and drain it completely dry, I left the last 1/2" of water in the bottom of the tank. I hadn't looked at it since until tonight, when I went to fill it up in preparation to putting some large BG in it to feed through next Winter.

Now, 3 weeks before I drained the tank, I put about 55 FHM in it with the RES. The Redears ate most of them, about 10 died, and there were 3 FHM left in the tank when I emptied it. I took these last three FHM to the pond with the RES just to empty the tank before shutting down the system.

Actually, there were 4 FHM left. I discovered a last survivor in the PBR tonight. It has lived for 2 months in 1/2" of water with no feed, aeration, or fresh water. That's persistence.

2. Can 100 Gams can outbreed 10 pounds of FHM?

The new pond got 10 pounds of Fatheads about 2 months before receiving 100 Gambusia affinis. Fish Wife and I have been discussing which species would produce the most forage over the course of this Summer. I had assumed that a greater number of FHM with a headstart would win hands down; she was counting on the Gams' (which she says are just big Guppies with good Marketing ) superior childrearing techniques (and earlier maturity?) to let them pull ahead.

I have a great many juvenile "minners" eating fish feed at the new pond each night now. I caught 10-12 of them tonight, and they all appeared to be Gambusia. I realize that Gams are very surface-feeding oriented, so they may show up disproportionately in this sampling. But I was still surprised that there were no FHM up on top near the shore at all.

I have a minoow trap in the pond, but as usual my luck with it has been poor. I will have to add some of DD's recommended stale bread and see if I can get any Faheads to show up. I may not get good numbers of minnows to examine until I seine sometime this Summer.

Any ideas who will win the startup forage reproduction derby?

I will bet on the guppies too.

In the absence of predators I think you'd get more FH by weight, but with predators the Gams will probably win.

Only current predators are 25 adult RES and 1-2 Little Green Herons. I will be adding some Male BG through the rest of the year, as ones over 8" in length I like the looks of are caught.

I've been feeding my FH pretty heavily and the population has exploded. I recently baited a minnow trap to try and see how the yoy RES are doing and after 15 minutes it was full of FH. You can't throw a fish pellet anywhere in the pond without a FH finding it in short order.

After 3-4 observation periods, I believe I have learned to distinguish the FHM from the Gams at a glance (Gams are lighter in coloration and swim differently, more agile-like).

In the top 1' - 1.5' of water, the Gams and FHM are roughly in equal number currently. The Gams are more comfortable on the surface (as one would expect) and are more aggressive at feeding on Aquamax pellets. Assuming there are fewer Gams as you go deeper, I figure the Fatheads still outnumber them, but nowhere near what a 30:1 advantage in stocking numbers and a 2 month head start would lead me to suspect. If the Gams have closed to gap this much already, I am pretty sure that they will outnumber the FHM by the end of the Summer.

I moved 15-18 juvenile Gams (and 2 adult FHM frm the minnow trap) to my older pond last night, and will move more when I get ahold of them. I am interested to see what the Gams can do in a pond with established BG/LMB/etc. populations. I do not expect a long term presence there (I figure they will get wiped out under the ice in the Winter) but I want to see if they are prolific enough to make a visible presence even with what should be serious predation.

Theo if you're talking about numbers of individual minnows the gams will have an edge because they're smaller. A full grown FH must weigh almost 10 times what Gams weigh (averaging males/females).

One possible factor is that Gams breed continuously (I think) and you get two spawns with the FH. The Gams may gain steadily though the summer but the FH will gain a lot in the fall.

I also think that most of your FH will stay deeper, at least that's what I've seen in the two ponds I manage.

Theo,

This may be apples/oranges, Louisiana/Ohio, but here's my experience.

In 2 years of coddling, babying, feeding, I have zero FHM in my pond, while the edges are presently black with baby gams.

My last ditch effort is a small (~10x10)minnow pond with 100% FHM. After 6 months, I have had a pretty good spawn, and the 15 FHM I seeded appears to have grown to ~500. My idea is to feed heavily, and see just how many FHM the little pond can hold. I am continuously pumping water (with a solar pump) into my minnow pond from the main pond at around 2gpm during full sun.

In my observations, FHM behave like fish. They are shy, and must be feed trained about like BG. Gams behave like guppies, are naturally feed trained, and can be habituated to feed from your hand.

Before my BG got some size on them, my female gams grew to a huge size, almost 1/2 the size of the FHM. Now the adult female gams average much smaller, a bit over 1/4 the size of the FHM. Naturally, the smaller females bear much smaller clutches, but I think greater numbers make up for it. I intend to make some L-shaped "breeding bays" on the edges of my pond to further enhance gam breeding success.

I believe FHM have the potential to out breed gams by 2:1, but in the real world, I suspect it is the opposite. In my warm water pond, the FHM got skunked. I'm thoroughly disappointed with FHM, and will probably give up. I wanted to have 4 layers of plentiful forage for my BG, BC, RES, and LMB fingerings (FHM, gams, crawfish, and shrimp). I guess 3 out of 4 isn't too bad.

I don't have any experience with FHM but I do with Gams. I put 70 Gams in my pond and quickly reduced their numbers down to about 35 (sniff, sniff). In the presence of LMB and GSF and later RES and BG the Gams have exploded in population. I now have two or three schools of Gams and each school must number in the thousands. Based upon my observations this year it seems as though the Gams were amoung the first to spawn. We started seeing Gam fry before anything else.

DIED added only 9 Gams into his ponds and he had thousands when we netted some for my pond and that was in the presence of GSF.

I don't know anything about FHM other that what I've read which seems to indicate that FHM are somewhat slow and clumsy. Gams are not they are quite fast and agile.

I didn't realize that Gams got that big. I think that Gams have a definite advantage when it comes to predation because of how close into shore they stay.

I'm not surprised that they come to your hand bobad, in fact if you left your hand in the water long enough it wouldn't surprise me if they ate it.

I think I may have had better than average luck with my FH spawn. I moved maybe 400 adult gams from my neighbor's pond to mine this spring and now they are everywhere. When they went in they were the only fish and I saw new fry steadily for many weeks. I saw spawning colors and behavior for at least a six week period.

I think it's true that FH need to be feed trained. I feed mine daily and they go to the pellets immediately. My neighbor feeds sporadically and his are more shy. I feed mine pretty heavily and they seem to put weight on rapidly.

I'm trying to figure out which I have. I know I have some FHM & Rosie Reds, but think what I'm seeing around the shore might also be Gams. It's hard to tell with the smaller ones (except the Rosies), but the larger (1.25") have a real fat belly. Whatever they are became feed trained instantly. Does anyone have pictures of each?

Stock photos, what I've used to distinguish.

Male Fathead (the females have slightly pointer noses and no bumps - breeding tubercules - on the nose):
Note the terminal (front end) mouth, notched tailfin.


Gambusia affinis (the species of Gam I have):
Note the (supraterminal?) up-turned mouth, rounded tailfin. Dorsal fin is farther back, too.

Thanks Theo. What I'm seeing are definitely Gams (which I didn't stock), and there are Fatties which I did stock.
Does anyone have picture? Silly me

Here's a thought; If you have FH and Gams in the same pond it's not unlikely that the Gams are preying on the FH.

And that's cheatin'.