Hedgehogs more at home in cities than rural areas: study

Hedgehogs - a 15 million year old species - have survived all kinds of environmental changes over the years, including urbanisation, and are now found more in cities than in rural areas, a new study has found.
Researchers fitted free-ranging hedgehogs with temperature-sensitive transmitters to study what physiological factors allow them to thrive in urban areas.
"These specialised transmitters allowed us to monitor hibernation patterns and nest site use in winter, as well as activity and home range size in summer," said Lisa Warnecke from University of Hamburg in Germany.
The study sites included areas with both major, busy roads and small, quiet side streets - all the elements of a typical city design.

Researchers also studied hedgehogs being cared for by a local hedgehog sanctuary to determine the main heath issues affecting city-dwelling hedgehogs.
The results showed that urban hedgehogs can be surprisingly flexible, researchers said.

"We found that urban hedgehogs had much smaller nightly ranging areas than their rural counterparts - 5 hectares verses 50 - and that they adjusted their activity to levels of human disturbance," said Warnecke.
The hedgehogs mainly stayed in private gardens during the day but around midnight, when the number of humans and pets in local parks decreased, they came out to forage and look for mates, researchers said.

Urban hedgehogs showed similar hibernation patterns to rural populations. Over the winter, hedgehogs enter a physiological state called torpor, where their metabolic rate and body temperature decrease significantly in order to save energy, they said.
"We were surprised to find that city hedgehogs showed hibernation patterns very similar to rural or captive populations in terms of the depth of torpor, the frequency with which they rewarmed and the overall duration of their hibernation," said Warnecke.
"This was despite city hedgehogs often nesting next to busy roads and having potential food sources available throughout winter - such as food scraps or cat food on private terraces," Warnecke said.

"This makes it imperative that urban hedgehogs can access gardens or parks with enough ground cover to allow them to be undisturbed for the entire hibernation season," she added.
"Our work with the hedgehog care station showed that the main problems were injuries caused by fences, plant netting or gardening tools, and sickness from ingesting rat poison," Warnecke said.