It's been a while since there was a dog and cat census in the UK - about three cat years or twenty human years in fact. They've gone undetected, hidden behind the sofa, curled up in the laundry, and therefore not considered much of a subject for scientific peer-reviewed journals. So for all this time it's escaped our notice that numbers of domestic dogs and cats are increasing, and while cats and dogs are owned by people with similar characteristics, cat owners are more likely to be qualified to degree level.

A study was undertaken in 2007 by Dr Jane Murray and colleagues from the Department of Clinical Veterinary Science at Bristol University and published in the Veterinary Record. Their aim was to ascertain the number of domestic cats and dogs in the UK and identify the characteristics of their owners. The telephone survey was given to randomly selected households from the electoral roll.

Overall they found that cats and dogs were owned by 26% and 31% of households respectively, and when extrapolated to UK census information determined that equals 10.3 million cats and 10.5 million dogs in 2006 - far more than has previously been estimated. Cat and dog numbers were last estimated in a scientific peer-reviewed journal in 1989, which said there were 6.2 million and 6.4 million respectively in the UK. While we've not been paying attention, they have been forming their armies.

Characteristics of dog and cat owners were also identified. Cats were more likely to be owned by; households with gardens, semi-urban or rural households, households with someone qualified to degree level, females and people aged less than 65 years. Cats were less likely to be owned by households with one or more dogs.

Dogs however were more likely to be owned by; large families, households with gardens, rural households, females aged less than 55 years, but less likely to be owned by; households with someone educated to degree level, households with cats or children aged less than 11 years. Therefore much the same profile but coupled with small children and no tertiary education. Dogs were less likely to be owned by households with one or more cats. Perhaps a house just isn't big enough for the both of them and first to the litter tray wins.

The number of owned cats and dogs were therefore predicted by two variables: the number of people in the household, and geographical location (London/rest of UK). These figures are useful to the animal health and welfare professions, including rescue charities, who will use these and future estimates to assess population changes. It is recommended by the researchers that another census is carried out in 2011 to monitor trends in pet ownership.

Dr Jane Murray, Cats Protection Lecturer in Feline Epidemiology, noted the similar owner profile for both cats and dogs but is unclear why a difference in education should affect pet ownership. She suggests, "It is unlikely to be related to household income as this variable was not shown to be significant but it could be related to household members with longer working hours having less time available to care for a dog."

Still, as a cat owner I shall be bathing in the warm glow of knowledge that cat owners are smarter than dog owners, and if you're a dog owner, I suggest you go lick your wounds.