The heron is one of nature’s most beautiful sights.  It stands tall and elegant with a striking colour pattern, and in flight looks like it has the wings of an eagle.  As a fisherman, it has great skill – hours of perfectly still patience followed by stabbing its prey in a flash with a snap of the neck.

However, that is in a natural setting.  When a heron visits a goldfish pond, it doesn’t need any patience.  There is crystal clear water with brightly coloured goldfish that can be picked off at will.  No need to wait for a fish that is the same colour as the murky water it is swimming in.

Apart from the obvious problem of quickly removing goldfish from a pond, herons cause a number of other problems for goldfish.   Firstly, they are disease carriers.  Secondly, if they don’t introduce a disease to the pond, an attack could increase stress levels in the remaining goldfish to levels that make them susceptible to disease.  Thirdly, they can spear a goldfish only to discover it is too big to swallow.  When that happens, they leave the goldfish by the side of the pool to die.  Whether or not suffocation kills it before the stab wound, it will die in agony.

Therefore it is very important to do everything possible to prevent heron attacks, and there are a number of methods available.

Hiding Places

Put some sections of pipe or upturned flower pots with entrance holes in the pond.  Goldfish can use these to shelter in when they see a heron at the surface of the water.  Unfortunately the goldfish will need to have been attacked at least once before knowing what a heron looks like, and taking advantage of the hiding places.

Netting

Netting stretched tightly over the surface of the pond will prevent herons taking goldfish.  The problem with this method is that it is unsightly and makes feeding the goldfish more awkward than it should be.  Having said that, a net should be used for a while after the first heron attack.  This is because the heron will be sure to return for more easy pickings.

Fishing Line

Herons usually won’t land in the pond, because they know it will scare the goldfish.  They prefer to walk up to the pond and launch a surprise attack.  A length of fishing line across the path of the heron about a foot (30cm) away from the pond and a foot off the ground will give a heron a fright when it trips over it.  The RSPB recommend using two lengths at about 6 and 12 inches off the ground.  However, herons will get wise to this trick, and use other approaches.  Then the whole pond will have to have a perimeter round it.  Eventually the heron will learn to land inside the perimeter, or on sturdy plants inside the pond.  If the pond is quite large, they will most likely land in the water anyway.

Scarers

Various forms of scarers can be used.  Some rely on a constant flow of water causing sudden movement on a hinge, others use trip-wires or infrared detectors to set off loud bangs or squirt jets of water.  Whatever method a scarer uses it will most likely be expensive, and a patient heron will eventually get used to it.

Plastic Herons

Plastic herons are sometimes placed in ponds to make real herons think the territory has already been claimed.  Many goldfish pond keepers dispute this, and point to the fact that herons looking for a mate will very often land beside a plastic heron, realize it’s not real, then eat all the goldfish.  On top of that, a hungry heron won’t care if another heron appears to stand between it and a meal.

Routines

Probably the most effective long term method of preventing herons taking goldfish is to train the goldfish when to come to the surface of the pond.  Always feed them at the same time every day, so that they eventually get to know when to come up.

On the other hand, break up the routine of going to the pond.  Herons watch and wait before deciding when to attack a goldfish pond, and will not do it when they think a human will be in attendance.  They will work out when the coast is clear and fly in.

Approaching the pond at unpredictable times but feeding at predictable times means that the goldfish will know not to surface every time they see a figure at the side of the pond.

Obviously if a house is left unattended at regular times for long periods this method will not work.  Neither will it work at the crack of dawn when most people are still in bed.  However, if it is done when possible it is very effective.  It foils the heron’s plan at the earliest stage – before it gets anywhere near a pond.  Outwitting the heron is something no fishing line, net or banger will ever be capable of.

Summary

It’s a game of cat and mouse.  Herons will always be attracted to goldfish in a pond.  Hiding places should be provided as a matter of course, and trip-wire may be necessary at some point.  However, the main thrust of any anti-heron activity should be to make the pond more hassle for the heron than it is worth at another pond.  Herons will visit a number of ponds looking for an easy meal, so a pond that gives them a bit of hassle should quickly get taken off the list.

However, other herons will take a look, so it’s important to remain vigilant and keep on top of the situation.

Tags: goldfish, heron, pond

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