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We recently saw a heron catch a wounded bird. It decapitated it then took it to the water’s edge and ate it. I thought they were fish eaters, or will they eat other things if it’s an easy catch? Lesley

How common is it for herons to ‘nick’ moorhen chicks? This weekend I saw a heron bully two adult moorhens until they moved from the nest and it then nicked a chick and flew off! Tessie B

Herons aren’t fussy eaters and have a very varied diet which includes small mammals, insects, little birds and amphibians as well as fish. They will catch birds up to the size of a water rail, so moorhen chicks are just a small snack.

Despite their long neck, herons have the same number of vertebrae as other birds but the bones are specially configured so that herons can bend their neck into an ‘S’ shape, allowing them to strike quickly. Usually, herons rely on stealth for hunting, waiting motionless before launching their long, sharp beak to snatch a fish or other prey. This technique is imaginatively known as ‘standing still’. Another technique is ‘walking slowly’, during which, yes, you’ve guessed it, they walk at a very slow pace to prevent spooking their prey. However, herons are large birds, standing about a metre high with a two-metre wingspan, so they’re not afraid to use brute force and bullying to get a meal if necessary, especially when they have hungry chicks to feed.

The type of food a heron chooses depends on the time of year and what is locally abundant in that season. Pellets collected from breeding colonies provide clues to which prey the adults are catching. Heron chicks are reliant on their parents for a long time, spending about 50 days in the nest, and they may not be independent until they are 80 days old. Herons are very adaptable hunters and can react to changes in prey availability, so the food brought to the chicks may change over the weeks. When there are plenty of small ducklings in May and early June, these can make up a large part of their diet. Some colonies feed mostly on small mammals such as water voles, mice, rats and even young rabbits. Although they are usually seen hunting in or near ponds and rivers, during the winter herons may hunt away from water, looking for small mammals in fields and pastures.

Herons will also make the most of a well-stocked garden pond if they find one, so if you want to hang on to your fish, try covering the pond with a fine mesh net and provide hiding places for the fish by planting waterlilies and other aquatic plants. You can also make it more difficult for herons to get to the water’s edge by encircling the pond with a barrier of taut strings or wires 20 centimetres and 35 centimetres above the water level. Herons are pretty bright birds so plastic decoy herons don’t appear to be much of a deterrent and may even attract a heron to hunt.