Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Releasing fish in to the wild

Pumpkinseed sun fish, Lepomis gibbosus
Pumpkinseed sun fish, Lepomis gibbosus


It is an all to familiar situation where a pet has outgrown its welcome, sometimes literally. What can be done with the unwanted pet?

Things to try

The first and most obvious thing to to do is to avoid being in that situation. It really is not that difficult to find out about a particular fish before buying it and to find out about its basic requirements it will need as an adult, quite simply if you can't provide for it as an adult don't acquire it in the first place.

If you are in the situation where you already have a pet which you can no longer cope with for what ever reason then you could try:

  • Advertising the pet to sell to someone who can cope with it.
  • Taking it to a local pet shop, don't expect to be paid anywhere near the retail price of the pet, by taking it they are doing you a favour!
  • Try offering it to a public aquarium but be warned they may already have more red tailed catfish and pacu that they can cope with themselves.
  • Try a fish rescue organisation.
  • If you still can't find a solution then the fish will have to be humanely put down.

Euthanasia is an extreme step to take but it is far better than misguidedly releasing the fish in to the wild where there is unlikely to be a good outcome for either the fish or the environment in general.

There are long lists of the damage caused by releasing non-native species in to the wild, quite simply this is the absolute worst thing to do.

Releasing the fish in to the wild

If you were to do this then the best scenario is that the fish quickly dies without passing on any infections. If it is a tropical fish and it is Summer then it may live a few months before slowly dying as the temperature drops, probably not what you had in mind eh?

If it is a coldwater species then it is entirely different. It is likely the fish would thrive if it could avoid predators and if it were to meet another of its species which isn't to unlikely because fish are sold in huge numbers and unfortunately quite a few are released.

If a foreign species becomes established it will displace some of the native species as has happened with Grey squirrels, Mink, Signal crayfish and so on. All of them have done untold damage to our native fauna through being released in to the wild, ironically in the case of the mink since it was released in to the wild by well meaning animal activist, the mink is responsible for bringing the once common native water vole to near extinction.

Signal crayfish have almost completely displaced the native crayfish because they carry a virus which doesn't affect them but the native crayfish has no defence against.

The grey squirrel has all but displaced the native red squirrel by simply being larger, more aggressive and more adaptable

This probably all seems a little extreme and unlikely just by you releasing your one fish in to the local canal or pond. But that really is all it takes. Some bacterial diseases for example can wipe out 90% of fish stocks in an area within a few days and the host doesn't always show signs of a disease.

Finally it is illegal to release fish in to the wild, even native fish can't be moved from one location to another without approval from DEFRA. The penalty for doing so is a fine up to £2,500.00.

"However, any release (of either native or non-native fish) to any inland water, other than an authorised fish farm, will still require Section 30 consent from the Environment Agency; failure to comply is an offence".

In short please never release fish in to the wild. No good will come of it and the potential for harm is to great to risk.

Act responsibly and dispose of it by one of the suggested means.

Would you like to:

  1. Harm the environment?
  2. Kill native species?

No!!! Then don't release alien species in to the wild.