Holes in fences for hedgehogs can reduce habitat fragmentation. But what is habitat fragmentation? It is the process in which large habitats get cut up into smaller pieces of the original habitat. Ultimately, the effect is that wildlife can’t move between different areas of the habitats due to a physical barrier (e.g. distances between different patches of same habitat being too far, roadway, dams, etc) and so the species are constrained to that particular area. This results in the gene pool (the variety of genes, with each variation of gene known as an allele being vastly reduced), increasing the likelihood that species will become extinct (it’s more vulnerable to sudden environmental change, or disease) as each individual of that species is more similar (genetically), than before.
One particular species suffering from habitats fragmentation is the hedgehog with populations decreasing by 66% within 20 years according to a study carried out by the UK Mammal Society and Natural England. According to the study, urban hedgehogs typically are doing better where there are both holes in the fences and untidy gardens (I will cover this in a future article).
Why are holes in the fences so beneficial for hedgehogs? A hole in the fence means that instead of a hedgehog being confined to a garden, it can move out and into a neighbouring piece of woodland, allowing it to continue to find food. This is of upmost importance when each hedgehog walks for 1-2km per night. It is however important to note that lack of untidy gardens and holes in the fences are not the only causes for the decline in hedgehogs, but we can easily change the impact these have.
So how should you go about creating a hole in the fence? First, and foremost get the permission of the person on the opposite side of the fence. Then, create a hole in the fence about the size of 13 x 13cm (5 x 5”), which is large enough for hedgehogs but pets from other gardens can’t get through. For guidance, that about the size of a CD case. Once you’ve done this, then your garden is instantly more attractive for hedgehogs and you’ll have more chance of seeing one. Repeat for each side of the fence.
If you’re feeling ambitious, then you could talk to each neighbour and try to persuade them to make holes in their fences. This will create a hedgehog gateway, whereby hedgehogs can walk through the gardens of the whole streets. It might help if you’re able to say “as soon as I put up a hedgehog hole in my garden, I saw X number of hedgehogs as a result”, or if you’re able to talk about the decline that hedgehogs suffer.