If you’ve ever woken up to a fox calling in the night it will probably have been during the winter: this is the time when foxes are most vocal.
Researchers have reported around 20 different sounds made by foxes (including eight distinct cub calls), and most of these occur commonly between December and February. Foxes are establishing breeding territories in the winter as they need to attract and keep mates and defend their patch against potential intruders.
Tracking Brighton's urban fox population
This is not conjecture – scientists have recorded a higher frequency of aggressive (e.g. screams, yell-whines) and contact (e.g. ‘ratchet’) calls in winter than in other seasons – and the specific frequency and volume of these noises mean that their purpose is most likely to relate to threat and/or pair bonding.
One reason for doing fox research is to tease apart fact from fiction, for example regarding foxes attacking or spreading disease to their children or pets. In our study we compare overlap between domestic cat and fox territories (in order to explore opportunities for disease transmission), and record mange, ticks and fleas on foxes when we trap them.
We hope to extend this to other parasites in the near future– in particular the canine and feline lungworms and heartworms, which are thought to be increasing. However information is lacking as to the risk of foxes passing them on to pets and people. What we do know is that the two canine species that are widespread in UK fox populations – ‘French heartworm’ and ‘Fox lungworm’ don’t infect humans.
Genetic and veterinary studies show that transmission occurs between foxes and dogs (and potentially between each of these and cats) causing persistent coughing, but infection is not known to be fatal. Neither are these parasites passed on directly - they need a vector in order to spread, and this is usually slugs, snails or mosquitos.
As to whether young children are safe in urban gardens – well, foxes are wild carnivores, and as such must be treated with caution. However, in my opinion the chances of foxes attacking babies or children outside are extraordinarily low. Common sense should prevail: don’t hand-feed or attract them into your house, but there is no need to be afraid of them.