LNHS Talks – London Hogwatch by Chris Carbone

Dear Readers, when I was in my twenties and thirties, our garden was positively awash with hedgehogs, from big lone males to whole families of hoglets. But the numbers declined, and I have never seen a hedgehog here in East Finchley. Recently, however, things have been looking up – I am hearing reports from the County Roads themselves of these spikey mammals being spotted, and only last week my friend A, who lives two roads away from me, rescued a poorly hedgehog in her garden and got him to a wildlife hospital. Could things be looking up for urban hedgehogs? I was looking forward to this talk to find out.

London Hogwatch is a case-study of urban mammals using camera traps run in collaboration with the Zoological Society of London (ZSL), and Chris Carbone has been involved with the project since 2016. The project overlaps with hedgehog studies in Regents Park, one of the last redoubts of the mammal in Central London. And, as the population of hedgehogs as fallen by over two-thirds in the past two decades, it’s a vital piece of research. The aim is to find out where the hedgehogs currently are, and to target these areas with campaigns and information to try to preserve them.

The project started in 2016 by concentrating on Camden, where the Zoo and Regent’s Park are situated. In 2017 it expanded to Haringey (not, I notice, to Coldfall Wood) and Richmond Park, and then on to Lambeth, Southwark and Sutton. Carbone explained that they are starting to do their first surveys in private gardens, and there’s a major programme of expansion planned for 2021, looking at Redbridge in East London for the first time (where I used to live and where hedgehogs used to be plentiful), and to other areas such as Hounslow and Enfield.

The projects have been run on something of a shoestring, relying on Masters and PhD students to do a lot of the analysis from the camera traps. I remember when I was running my camera trap that for every ‘valid’ photo of an actual fox there were dozens of cats, waving foliage and my legs going backwards and forwards to the shed, so I can only imagine the patience involved.

Carbone explained that camera-trap surveys had only really been possible during the past ten years – previous cameras were too big and expensive for widespread surveys. During the lockdown, cameras had been packaged up and shipped out for people to use in their own gardens, before collecting them back again, quarantining them and analysing the data.

There have also been a number of large-scale surveys. One, in Hampstead Heath in 2018, showed that there were at least 100 hedgehogs present. This was followed up in 2020 with some private garden surveys, which showed that gardens that were close to the area of the Heath where hedgehogs were present were also being visited by the animals, but that good habitat in places like Highgate Cemetery and Waterlow Park were completely devoid of hedgehogs, probably due to barriers such as the major roads that bisect the area, and walls and impenetrable fences between individual houses.

Studies also showed that there was a robust population of hedgehogs in the Barnes/Richmond/Roehampton area – an avid hedgehog fan in Barnes had been encouraging people to drill holes in their fences to enable the animals to travel between gardens. Camera trapping showed that there were lots of hedgehogs on Barnes Common and in the Wetland Centre, and that these were spreading out from this area, so this is an area of major importance for South London hedgehogs.

Interestingly though, to the south and west (i.e. in Richmond Park itself and the grounds of Roehampton University) there’s a population of badgers, who not only compete with the hedgehogs but will actually eat them. When Carbone showed his slide, there was a very clear demarcation between the areas where badgers were present, and those where hedgehogs were present. Although hedgehogs can co-exist quite happily with foxes and cats, it seems as it badgers are a step too far. However, badgers are much less likely to come into private gardens, and so Carbone feels that hedgehog highways and support from private garden owners can provide an important refuge for hedgehogs, where they are much less likely to come into contact with badgers.

Other surveys, such as one at Home Park which surrounds Hampton Court Palace, didn’t reveal any hedgehogs at all, but they did expose some interesting patterns of animal behaviour. Deer activity, for example, peaks very early in the morning before humans and dog walkers appear, and tails off to a much lower level when the park is being highly used. On Hampstead Heath, birds also try to avoid busy human times. With the usage of public greenspace having become so much more intense during the lockdown, it might be a while before some new balance between human and animal activity is achieved in our busiest parks and reserves.

So, what areas are good for hedgehogs, and what do they avoid? A predictive map of areas that should be good for the mammals has been built up from historic data gathered by other organisations and London Hogwatch, and the results show that:

  • Areas with badgers are really no-go areas for hedgehogs, as mentioned above
  • Allotments and gardens are good for hedgehogs, particularly if they have lots of invertebrates living in them
  • But! a lot more data analysis needs to take place to determine exactly what they need.

One big problem is genetic isolation between populations. There are a hundred hedgehogs in Hampstead Heath, and about thirty in Regent’s Park. There’s only about a mile and a half of distance between these two populations, but between the roads, the walls, the fences and the swathes of concrete it would be a very lucky hedgehog indeed who managed to make the trip unscathed.

Another is the dangers posed by our roads. Carbone shared a photo of a sadly-squashed hedgehog on a zebra-crossing in a 20 m.p.h. zone, taken during lockdown. If a hedgehog can’t avoid getting run down under these circumstances, what chance does it stand of crossing a busy road during normal times?

So, what’s the future for hedgehogs, and for London Hogwatch? Carbone outlined a few key points. Firstly, the organisation wants to identify current hedgehog ‘hotspots’ and concentrate efforts on those areas. Secondly, there is a whole debate to be had about use of public greenspace, and how to balance the needs of humans and of urban wildlife. Thirdly, we need a better understanding of the relationships between different urban species. Finally, Carbone thinks that there needs to be better partnerships between different sectors and stakeholders – there’s a tendency for people not to think ‘outside the box’ of their own particular interest area, and this can make things very challenging.

Carbone was asked about how people could help hedgehogs, and he had a number of ideas.

  • The hedgehog highway idea is very important – this works best where a small community agrees to, for example, make routes through their garden fences so that the hedgehogs can access food from a range of gardens.
  • Feeding can work, but it’s important to make sure that you do it in such a way that you aren’t also feeding all the other urban wildlife
  • You can buy hedgehog ‘houses’ and nests which can be useful in some circumstances
  • Carbone is not in favour of translocating hedgehogs, but thinks we should foster hedgehogs where they occur naturally – if hedgehogs are not already in an area there might be a good reason for why they aren’t there.

In short, this was an interesting talk that gave a good picture of what is currently going on in the field of London hedgehog research. Personally, I would have loved to know a bit more about possible reasons for the decline (I blame slug pellets and increased traffic, but who knows?) but I learned a lot, and I certainly wish London Hogwatch all the best as they expand into new areas of London. It will be good to hear about what they discover.

You can watch the whole talk here.

London Hogwatch doesn’t have a website yet (though they do have Twitter at https://twitter.com/londonhogwatch?lang=en, but I found this map from Hedgehog Street to be very useful.


1 thought on “LNHS Talks – London Hogwatch by Chris Carbone

  1. Alittlebitoutoffocus

    There certainly doesn’t seem to be as many hedgehogs as there used to be (when I were a lad!) I think I’ve only ever seen one in Switzerland and that was on the road outside our old apartment. On the other side of the road was a huge wall, which ran for a good 50 to 60 metres, so I carefully picked it up and placed it back in the garden.
    I think I mentioned that we had a badger here recently so, from what you say, I guess it’s not surprising we don’t see them around our chalet.
    And my Trailcam has also shown lots of early morning or even overnight deer activity, though we have occasionally spotted them during the day.


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