IT IS NO BETTER FOR MOSQUITO CONTROL THAN OUR NATIVE SPECIES.
Small, dull grey fish, shaped a bit like the common aquarium guppy. Often people see them in our waters and call them guppies. They are sometimes also called mosquito fish. Swims, usually in schools, near the water surface.
Tolerates high temperatures, low oxygen levels, high salt levels and other pollution.
It is a danger to native fish.
Gambusia is a PEST as it competes with our smaller native freshwater fish for food and resources and also eats their eggs and nips at their fins and tails. One study has even shown that native fish are unable to reproduce when kept with Gambusia.
Gambusia breed like crazy. A mature female Gambusia can produce 5 broods of live young in a season, after only one mating. The young from these broods can themselves breed from the age of 4-6 weeks.
No Australian native fish can produce anything like as many young, and our small native freshwater species are all egg layers. They are already at a disadvantage from Gambusia. The eggs and young are eaten by Gambusia. If the young hatch they are much smaller than the newly spawned Gambusia that they must compete with.
A CONSERVATIVE ESTIMATE OF THE NUMBER OF YOUNG PRODUCED BY ONE FEMALE AND HER PROGENY IN A SINGLE SEASON IS 9,000.
Gambusia is a danger to native frogs. Gambusia eat eggs and tadpoles of frogs, and has been specifically implicated, among other factors, in the decline of the threatened Green and Gold Bell Frog.
What can you do?
Gambusia is listed as a "KEY THREATENING PROCESS" under the NSW Threatened Species Conservation Act. This is the first time in NSW that a fish has been legally declared an environmental hazard. So, to prevent its spread:
- DO NOT TRANSFER THIS FISH FROM ONE BODY OF WATER TO ANOTHER.
- DO NOT RELEASE THESE FISH INTO ANY WATER, NOT EVEN A BACKYARD POND.
If you want to get rid of unwanted aquarium fish, take them to an aquarium shop. Reputable aquarium shops will accept them, as they do not wish to see feral fish in Australia's rivers.
