By Jody Bourton
Earth News reporter
House hunting, the urban hedgehog
A study of urban hedgehogs has found they prefer certain types of garden.
Female hedgehogs prefer to use the back gardens of semi-detached and terraced houses, rather than detached homes.
Such gardens provide ample food, but are safer, as female hedgehogs are less likely to be attacked by urban badgers, or be disturbed by dogs or people.
However, male hedgehogs take more risks and are more likely to roam across gardens of larger detached houses to find new mates, finds the study.
Details of the study are published in the journal Animal Behaviour.
Late night life
Hedgehogs (Erinaceus europaeus) living in an urban environment have to adapt to many obstacles and potential hazards, including the threat of busy roads, pet dogs and a lack of suitable habitat.
In order to understand how they behave, scientists used small radio transmitters to track the night time movement of hedgehogs in the city of Bristol, UK.
This revealed hedgehogs are more active after midnight than before, perhaps in response to the marked reduction in human activity during the small hours of the morning.
This was true even when the weather was warm, and levels of food were high, further suggesting that avoiding people and dogs is a major part of their survival strategy.
"I was particularly surprised by the fact that the hedgehogs were so much less active before midnight," says Professor Stephen Harris of the University of Bristol who undertook the study with colleagues from the University of Reading, UK.
"The risks posed by people, dogs and cars must be so high that they reduce their activity levels despite the food that is available."
Hedgehogs prefer back gardens rather than front gardens.
Again, this may be because these are places where the insectivores are not exposed to humans or pet dogs being walked at night.
"There is a popular misconception that life for hedgehogs is a lot easier in towns, and that hedgehogs are more abundant in towns than in the countryside.
"In fact, life in towns is quite hard, and this is the first study to highlight some of these problems and how the hedgehogs adapt," says Prof Harris.
The research also reveals that male hedgehogs choose different houses than females.
Urban badgers prefer to visit larger detached house gardens, which are easier to access and have more food.
Badgers predate on hedgehogs and female hedgehogs avoid them by preferring the relatively safer gardens of semi-detached and terraced houses.
Males though prefer the larger gardens of detached houses in the study area.
"Males take big risks in order to spread their genes," says Professor Harris.
In other areas this pattern may differ.
"Many urban areas do not have badgers, and so in other areas I would expect [female] hedgehogs to use large detached gardens as well," Prof Harris says.