Foxes savour lizards and seafood

Monday, June 04, 2012

A READER who is very fond of her cats has contacted me because she has spotted a fox in the garden and is worried it might kill the cats.

As far as I’m aware there is no authenticated record of a fox killing a cat. A lot of scientific work has been done on the diet of foxes. Most of this is done by analysing their faeces and I have never heard of cat bones turning up.

On the other hand, another reader has been keeping me updated for years on the friendship between his cat and a local vixen. He started feeding the fox when it appeared on his doorstep as a young and starving animal. Because of his help it has thrived and reared several litters of cubs. The friendship between the fox and the cat developed slowly but they are now completely relaxed in each other’s presence and will feed out of the same bowl.

This is a slightly unusual example, but it seems as though the natural enmity that exists between most dogs and most cats does not extend to foxes, despite the fact that foxes are closely related to dogs.

If we’re fairly certain that foxes don’t eat cats, what do they eat? This is a bit like asking what humans eat, because they are remarkably omnivorous. They are classed as carnivores, but at certain times of the year become almost completely vegetarian. The wide variety of their diet is the main reason that they’re such successful animals. Wolves have a less varied diet and they became extinct in Ireland about 250 years ago. Today, at the start of each breeding season there are somewhere around 150,000 to 200,000 foxes in Ireland.

The basic hunting strategy of a fox is to pounce on small mammals like mice and rats. Irish foxes, both urban and rural, eat a lot of rats — more than English foxes, for example. This is probably because there are more small mammal species, particularly voles, in England than in Ireland.

But there is some scientific evidence to suggest that individual foxes have taste preferences, just as humans do, and will concentrate on looking for a favourite food. On average they spend about a third of their time hunting and foraging. There is a fox living near me that loves blackberries and for about six weeks in the autumn it deposits extraordinary looking purple faeces around the place.

I once spent about half an hour hidden in a hedge watching a young fox. It spent the whole time digging strenuously in a corner of a field where the ground was soft and eating earthworms. They will also forage for slugs and snails or large beetles and, in summer, some will hunt grasshoppers.

Coastal foxes like seafood and will work rock pools for crabs, small fish and anything edible. Inland they eat quite a lot of frogs and newts, and lizards if they can get them. They will eat the eggs and chicks of ground-nesting birds such as pheasant or mallard, which makes them unpopular with shooting people.

Urban foxes scavenge for half-eaten hamburgers and rural foxes eat quite a lot of carrion — road kills, birds wounded by shooters and still-born lambs. There are arguments about whether they kill healthy, live lambs. The evidence suggests that they do occasionally kill both lambs and new-born deer fawns, but that this is unusual. The fact that a fox is seen carrying a lamb or feeding on its carcase should not automatically suggest that it has killed the animal.

* dick.warner@examiner.ie Home