While the numbers of many wild animal species have declined dramatically with increasing urbanisation, others have managed to adapt and survive, or even thrive, in these relatively new environments. Think of house mice, easily seen even in rush hour in underground tunnels. Or rats, feral pigeons and foxes. Suburban gardens seem to quite suit hedgehogs, as long as they can move between them, and the gardens aren’t too sterile in their perfection. But how do they get on in truly urban areas?
Not very well, so it seems. I heard a very interesting talk on hedgehogs in central London, by Nigel Reeve, at the Surrey Mammal Group meeting a couple of weeks ago. Central London is blessed with a number of large parks (including Hyde Park, Green Park, St James’ Park) and numerous smaller garden oases in squares dotted around the city. But only one of those green spaces, Regent’s Park, is known to be home to hedgehogs. Regent’s Park contains a mix of formal gardens, sports pitches, amenity grassland and wilder areas, covering 166 hectares in total.
The Royal Parks, supported by a generous anonymous donor, have been conducting indepth research into this isolated population, to see what can be learnt to help manage the park better for hedgehogs.
With the help of around 70 trained volunteers, using a mix of spotlighting, footprint tunnels, camera traps, radiotracking and GPS tracking, they have now established that there are around 50 hedgehogs living in the park. This doesn’t seem too bad, at first glance. But it gives a hedgehog density much lower than that reported in other studies in the UK. And that population are completely cut off from any other hedgehogs – there’s no connectivity with parks and gardens further out of London, like Hampstead Heath, where there are hedgehogs. This makes the Regent’s Park population very vulnerable.
In an entirely unscientific comparison, to put it into perspective, Regent’s Park contains 50 hedgehogs in 166 hectares. My garden, which is 0.005 hectares (I know, I’m practically landed gentry!), was used by at least 6 different adult and 3 young hedgehogs in 2011.
The research team got a wealth of information from their study. The points that stood out for me were:
- The hedgehogs they found were good weights (heavy for the time of year compared to hedgehogs found in other studies)
- The hedgehogs were mostly found by the lake, formal gardens and zoo carpark
- The radiotracking found that nests were mostly in the ‘informal shrubbery’, which includes areas of bramble and scrub
- Half of hedgehogs used more than one nest in a single week
- Short grass is a very important foraging habitat for them
- Hedgehogs on average moved around 600-900m a night
Having got all this data, they have fed it back to the park staff, along with recommendations on how to encourage the fragile hedgehog population. They’ve also been doing work with the local community to raise awareness of hedgehogs, to try to protect this vulnerable population. Further research is happening this year.
You can read more about the study on the Royal Parks website.