little to do with the trade and is all down to irresponsible hobbyist.
Who either having become fed up with their fish or through buying a fish
that grew too large. These individuals simply go and release it/them into the wild. Some are
just glad to be rid of them and others do so reluctantly thinking
that they are releasing them to a better life now that they are too big
to cope with.
This has caused environmental trouble all over the world. All fish are a
part of the eco system where they normally live, they have evolved to
fill a niche. They have prey and are preyed upon and a balance is kept.
When a fish is placed in a foreign environment one of several things can
fish will be exposed to new diseases which the native species are
almost immune from, and will quickly die.
temperature range is out of the fishes tolerance level and it will
fish will expose the native fish to a disease that they have no
defence against and they will die.
fish could be predatory and cause havoc in a local area.
not just scare mongering, all the following are real examples of what
can happen, when fish are released in the wrong place even when it is
done with good intention.
Africa, Nile perch are released into Lake Victoria as a food source.
Result, they make extinct 90% of the Lakes endemic Cichlid species
those fish have gone forever and the Nile Perch now prey on each other
so nothing has been gained, only lost.
Africa, Mozambique Mouth brooders (Tilapia) have been widely introduced
into lots of waterways and quickly replaced the indigenous fish due to
them being so prolific and adaptable.
Wels Catfish was released into a bird sanctuary lake, Wels Catfish are
one of the worlds biggest freshwater fish and voracious predators.
They were routinely sold at around 3 or 4 inch for years but they
quickly out grow any size of tank and were often put in a garden pond
or a friends garden pond once their tank was to small. then once they
began to eat expensive Koi or Goldfish they were often released in to
the wild. There are strong rumours too that anglers would release them
in various water ways for future sport. Anyway getting back to the one
mentioned earlier, it found conditions in the sanctuary lake very much
to its liking and quietly grew and grew unnoticed by anyone.
That was until it reached 5ft in length and 140lbs in weight and began
to prey on adult swans having cleared up all the fish in the lake. And
that was just a single specimen imagine if there were a few of them
and in a less restricted environment.
a similar theme, it is thought that almost every body of water, canal,
pond, lake etc has some Terrapins living there in the wild.
Lots of N American fish can now only be purchased if you hold a
license. This could be the first in a long line of ever increasing
Piranha, Oscars and lots of other species are now establishing wild
populations in the warmer States like Florida.
Large numbers of Flowerhorn Cichlids have been introduced into the
wild because they were rejected by breeders. Flowerhorn Cichlids are
large predatory fish that have been made by hybridisation, they are
not a true species and as such they don't belong anywhere in the wild.
to keep the hobby in its present fairly unrestricted form everyone
connected with it needs to be seen to be acting responsibly and thus
avoid the need for further restriction.
buy species that you can't keep as adults.
Never ever release fish into the wild under any circumstances.