February 2019: Nature Watch

January 24 2019

WE have occasionally had squirrels in the loft and they are terrible upstairs neighbours.

They wake early and go to bed late, they stomp about and chew things they shouldn’t. But because they are so cute we just think, “little tinkers” and smile a wry smile and quickly re-seal the old entry point, job sorted.  So, I was wondering, why do we feel so differently about rats? When you see a rat near your house it doesn’t tend to make you think, “little tinker” with a wry smile, it makes you think of traps and poisons. As The Mammal Society website puts it “as an alien, a major pest of stored foodstuffs, and the carrier of various human diseases, the common rat is persecuted rather than conserved.” Exactly.

 But do they have any good points? Originally from Asia, the brown, or common, rat was introduced to Britain in the 1700’s and has all but ousted our native black rat. It possesses a formidable adaptability, agility and intelligence. Brown rats live in family groups within small communities, with maternal care for the babies. They are nimble and can climb and swim very well. They have fallen five storeys and survived. They balance a great adaptability (seaside dwellers will dive for molluscs, a novel food for rats) with a great fear of the new - making it hard to bait them with poison. It seems that centuries of persecution have unwittingly selected only the most intelligent rats for survival: in some tests they have beaten human subjects by learning more quickly and being better at the test! Brown rats seem to be at least as good at problem solving as dogs which is one reason why they have become so popular as pets. When tickled or scratched by somebody they trust, a pet rat will emit a chirrup, which indicates they are feeling pleasure. Researchers compared it to laughter in humans – rats seem really to enjoy the company of their carers.

 But they are not just intelligent; given a choice between liberating its cage-mate and getting a chocolate treat a rat will free its mate first and then share the chocolate! I know people who wouldn’t do that! 

And if you still need convincing, we are finding some clever ways of using the abilities of rats. They have been trained to detect tuberculosis – they can smell the disease in a sputum sample – providing a quick and easy test that saves money and lives. And, to be fair, they have made a great contribution towards combatting human diseases, albeit involuntarily as test subjects. 

So, we may not want to welcome these wild mammals into our homes, but we must surely approve of new types of population control which act by contraception instead of death by poisoning. Together with making our homes rat-proof so they stay firmly outside, this surely offers a better solution to co-existing with these thoughtful, feeling creatures, who enjoy a tickle

Photo by Mrs Airwolfhound on Flickr