Largest mosquitofish (gambusia) sp?

[petspoiler]

Not all males that stay smaller. I had Innes strain of G.affinis, the males of this strain grew to same size of the mature female. I had a colony of Albino strain they dont eat their fry since their eyesight isn't good.

interesting. I've only ever tried the standard G. affinis which are (ahem) planted for mosquito control ;-) and I suspect/guess that the Dept does not want real vigorous sizes which could be more detrimental to native fish etc.
They will give them away by buckets full to ppl with a reason for needing mosquito control... which is causing me to ponder some things. LOL.
did yours have large broods?
I was thinking of trying some of the wild giant green swordtails. seems like they'd be easier.

 

[MN_Rebel]

interesting. I've only ever tried the standard G. affinis which are (ahem) planted for mosquito control ;-) and I suspect/guess that the Dept does not want real vigorous sizes which could be more detrimental to native fish etc.
They will give them away by buckets full to ppl with a reason for needing mosquito control... which is causing me to ponder some things. LOL.
did yours have large broods?
I was thinking of trying some of the wild giant green swordtails. seems like they'd be easier.

My albino strain had fertility problem so they don't give me alot of fry. My Innes and Giant Innes strain did gave me large batch but I had bumblebee gobies in that tank.....being so fat from eating the fry.

 

[ShadowBass]

To give an idea of spawning rate for the regular ones, I didn't even know I put any in my pond (they likely got put in with some plants), and suddenly I had hundreds.
They outcompeted my topminnows which I had a pretty good population of beforehand.
Now I can't even clean moss out of the pond without ending up with about 30-50 in the net.
They're a bane if you want any other small fish spawning in your pond/aquarium. Even with larger fish they'll eat the eggs and fry and may wipe them out eventually.

 

[petspoiler]

To give an idea of spawning rate for the regular ones, I didn't even know I put any in my pond (they likely got put in with some plants), and suddenly I had hundreds.
They outcompeted my topminnows which I had a pretty good population of beforehand.
Now I can't even clean moss out of the pond without ending up with about 30-50 in the net.
They're a bane if you want any other small fish spawning in your pond/aquarium. Even with larger fish they'll eat the eggs and fry and may wipe them out eventually.

I honestly know nothing firsthand about strains.
"Gambusia affinis (native to southern and eastern portions of the United States)" are what they use here for mosquito control.
Perhaps these just proliferate better in natural conditions, than in aquaria.?
I observe in ponds & creeks, fry hide in shallow edges with thick moss & grasses etc where nothing else can go. Females drop them and run. males pursue females relentlessly. Lll.
In tanks, I haven't seen cannibalization as primary limit on the multiplication rate. they really just drop small numbers of fry.

 

[ShadowBass]

You sure they're not eating them? Mine still drop plenty of fry in tanks, maybe not as many as in my pond, but they just don't last long unless there's a ton of cover. The others will literally eat fry as soon as the females pop them out.
If you don't have pretty dense floating plants or something they're going to be eating them.

Type of food may change things too. With most of my fish they tend to produce more eggs or fry on meaty high protein foods. I don't even feed the fish in my pond, they just eat algae, worms, and bugs. Especially tons of mosquito larva in the summer.

 

[ShadowBass]

You sure they're not eating them? Mine still drop plenty of fry in tanks, maybe not as many as in my pond, but they just don't last long unless there's a ton of cover. The others will literally eat fry as soon as the females pop them out.
If you don't have pretty dense floating plants or something they're going to be eating them.

Type of food may change things too. With most of my fish they tend to produce more eggs or fry on meaty high protein foods. I don't even feed the fish in my pond, they just eat algae, worms, and bugs. Especially tons of mosquito larva and spawning adult mosquitos in the summer.

 

[MN_Rebel]

The fry has a poor survivial rate if kept in same tank with the adults, no matter how thick the cover are. I kept 9 different strains and four species of Gambusia in the past. If I see a fry, I remove them right now. Man I missed my old days of raising the exotic livebearers.

I fed them high protein foods (mainly bloodworms) but they become very cannibalistic and will readily seek out the fry. The ones that I fed with just flakes and they don't try to seek out the fry to eat them and still produce same number of fry.

 

[petspoiler]

You sure they're not eating them? Mine still drop plenty of fry in tanks, maybe not as many as in my pond, but they just don't last long unless there's a ton of cover. The others will literally eat fry as soon as the females pop them out.
.......

well I must've missed an awful lot of action :-/

 

[ShadowBass]

Like I said, mine don't seem to have as many fry predation or aggression issues as other people's seem to have. I'd guess there's some difference between strains. I've even seen several people on NANFA mention that they can't keep a colony going at all because they eventually decimate each other, but I haven't had that issue either.

The high protein thing shouldn't be related to predation though. It's to help produce more fry/eggs in the first place, regardless of species, since higher protein - assuming it's usable and other necessary nutrients are present for adequate absorption - is generally shown to be beneficial for reproduction. Livebearers, including mosquitofish, have also been studied individually in regards to protein vs fry production, and higher proteins up to a certain amount were linked to higher fry production. Once you get above a certain protein level the reproduction difference is negligible, but up to a certain percentage it's noticable.
Flake or pellet can be high in usable protein also, it depends on what you feed.
I have no clue why frozen or live foods would encourage excess predation. I haven't noticed such, and like I said, my pond fish only eat live foods available to them naturally, and their population certainly isn't dropping.
I'm not disputing that you saw this, I'm just not sure what factors would lead to such behavior, whether genetic, nutritional, or environmental.
Bloodworms exclusively aren't a diet with varied nutrients, so perhaps they were missing something that caused them to feel the need to heavily predate other fish. High quality flake food is fortified and and formulated to be nutritionally complete. But that's just a hypothesis.