Herons and garden fish ponds
3 June 2004
A pond in your garden is attractive and provides an extra habitat for wildlife. A pond with gently sloping sides will be used by small birds for drinking and bathing, and may attract toads, frogs and newts, or even herons.
If you keep ornamental fish in the pond, you may prefer not to receive visits from a heron.
Herons eat mostly fish but also take amphibians and small mammals, with small quantities of reptiles, insects, crustaceans, molluscs, worms and birds. Herons fish mostly at dawn and dusk so they are rarely noticed.
Young herons teach themselves to fish, and when they leave their nest in June and July, small garden ponds are attractive to them because they often provide easy fishing. Quite understandably, herons will respond to a garden pond in a comparable way to a blue tit being attracted to a nut feeder.
There are many ways that a garden pond can be made less attractive to herons, but remember that many of the ways of ‘heron proofing’ a pond will deny its use to other wildlife also. If you have/are likely to have a persistent heron problem, it might be preferable to forget about the fish and turn the pond into a thriving wildlife pond, where the heron would be a welcome component.
How many herons are there in the UK?
Grey herons are thinly distributed throughout the UK as birds of freshwater and estuaries. They nest colonially (in 'heronries') in the tops of tall trees. An estimated 15,000 pairs of herons nest in the UK (compare this with 3.5 million pairs of blue tits). In severe winters, when water freezes, making fish difficult to catch, the heron population can be reduced significantly.
Are herons protected?
In Great Britain the heron is protected at all times under the Wildlife and Countryside Act 1981, with fines or prison sentences available for anyone killing or attempting to kill one (see A brief guide to birds and the law, linked from this page, for further details). The heron is also protected under the Wildlife (Northern Ireland) Order 1985.
Government licences to kill small numbers of herons can be issued in very limited circumstances. These would normally be issued to owners of commercial fisheries where all other non-lethal methods have been shown to be ineffective.
There is no provision to issue such licences to protect ornamental fish. Owners of ornamental fish ponds who are concerned about the activities of herons should try and use preventative methods to make the area less attractive to herons and provide protection for the fish.
Pond design and management
Reducing the likelihood of herons eating fish from a garden pond is most effective if taken into account when designing the pond.
Consider what makes a pond attractive to herons, and incorporate a range of features that would make it difficult for a heron to get to the fish.
The least attractive pond and easiest to protect is the small, steep-sided ornamental variety with a good covering of lily pads harbouring half a dozen goldfish in a small urban garden.
The most attractive to herons (and very difficult to protect) is a large, unenclosed pond with gently sloping earth banks, leaping with fish, on a river floodplain near a heronry.