A friend of mine has a pond - not connected to any waterways or anything - that is teeming with Gambusia. He wants to get a predacious fish to put in it to eat them (like an Oscar or something, but obviously an Oscar wouldn't work in a pond in NZ). Does anyone know of any sorts of fish that would fit the bill?

an eel? might have to catch one from the wild though... but are you allowed to do that and keep them in a pond?

What about a couple of those chineese koi carp? :lol: :lol:

The great thing is they breed quite easierly as well. (did you mind having to pay a massive fine... can't remember?) :lol:

I remember you folks talking about these fish in another thread. If I remember correctly, they are not wanted in your waterways as they wipe out other species...plus, other reasons they are not wanted.

But, if they can't get into a waterway...if they are confined to a pond, why do you want to kill them?

your standard comet would do quite well on gambusia.

I know that they do like to chomp on the odd guppy or 6 :roll:

Not that I have done it

I was going to suggest you try to catch them and then use them a live food for tropicals however;

What damage do they do?

Gambusia populations quickly expand to outnumber other species. They attack native fish by nipping at their fins and eyes and prey on their eggs. Whitebait and mudfish species are especially vulnerable to Gambusia as they inhabit similar habitats.

Taken from DOC site,may be more trouble than worth.

What about just some comets?

Stuttered :oops: :oops:

Al

If the pond is an outdoors one, Oscars will hack it over summer in Auck no sweat.

I saw a homemade pond down Parapram, outside, that had heaps of baby oscars in it

Pond was made from concrete blocks, and lined with a piece of black polythene

May have to give them and umbrella to keep dry out of the rain tho, if the friend's place iss situated in Auck.

Alan 104

Yeah I was considering Comets, but was thinking they might be too slow and not aggressive enough. I'll recommend him putting an Oscar in it over summer to sort things out then Caper - he wants to get rid of them so he can put some other fish in

There's also the option of removing everything you want and draining/poisoning the pond. I think that'll probably be a lot more effective than an oscar.

It's quite a large pond (100m squared at least) and it's naturally formed so that might pose a bit of a problem. There are some shallow bits around the edges that an Oscar probably couldn't get into (but Gambusia could) so he might have to block that bit of the pond off. It's going to be quite a mission to get them out, he doesn't know how they got in there in the first place.

If it's that big I doubt a single oscar will even make a dent in their populations. Maybe dozen full grown ones would, but I think still they'd breed too fast to be wiped out.

Why not get in touch with MAF and tell them of your problem.

I'm sure they'd be only to pleased to help or at least tell you how to fix the problem.

There is such a thing as an electric fish stunner that they use.

Excellent contraption.

The other way that springs to mind is to lime it.

Not the citrus type tho.

Ask the MAFia about the amount to use.

That works really well.

I heard of a Koi pond in the Tauranga area that was discovered,

and the fish were annihilated with the lime.

Alan 104

packu, the big ugly ones,dont know how to spell it and dont care but thay can live in colder water

if thay do the job well, thay will be big enough to catch and eat or shoot.

If he contacts MAF won't he end up with a huge fine for having them in the first place?

Probably better to kill them all off somehow but how would that affect any fish he puts in afterwards?

Cheers

Jude

Aren't Pacu almost entirely herbivorous though? If not that might be an attractive solution, those things grow pretty huge and I'm sure there're some aquarium owners out there looking to offload an overgrown one or two.

He would only be reporting them Caper,

after finding out about them on this site and realizing that they are a hazard

Alan 104

Gambusia are called mosquito fish and are live bearers used in Asia as live fish food, hence the odd one has come into NZ with imported fish. They are distributed world wide because they were thought to feed almost exclusively on mosquito larvae, but they are actually not that good at controlling mosquito larva and will eat all sorts of stuff. Our dearly beloved trout and salmon fishers have no doubt convinced the Maf they are bad critters. I don't know if they are or not, but they are certainly not legal. Calcium oxide will kill them, and everything else as it uses up all the oxygen, but I am not sure how you get the life back into the water. A fish friendly Vet might have an idea on that or an alternative. I think you would need chemical control to completely wipe them out. Good luck

might as well give the oscars a go, or get a bunch of heaters and huge pumps and add some bad boy cichlids. I don't know if varieties of barbs would eat the fish as they may be too big but they can handle summer water temps outside too. let us know how you get on

couldn't you get some axolotls to eat em up? they're cute, cudly and would probably make short work of them bad fishy's. just my 2 cent's though.

Yeah Axolotls were considered but they're not really active predators, they sort of just sit and wait for fish to get right in front of their mouths before they snap. Pacus are being looked into further and we might try an Oscar in there for the summer.

why not just drain the pond, let it dry up and then refill it?

otherwise what type of fish does he want in there?

If you put in a lot of commets they would soon take of the prolem for you. Also adult angel fish in the summer would do a nice job too.

Like I said before it's naturally formed and at least 100m squared, how does one go about draining something like that?

Light a fire

Have the fire hydrants filled with concrete

And hey-presto

The fire brigade will pump it out for nothing.

Oh well, back the the drawing board.

Alan 104

http://nature.sbc.edu/animals/gambusia.html

http://www.fnpw.com.au/enews4/gambusia.htm

Wow...could be a lot of work getting rid of these fishies! I've been checking on the net to see if I can find how to get rid of them and so far doesn't look like an easy task!