How many hedgehogs in Guernsey?
Curious about how we will use your hedgehog watching observations to calculate the total population in Guernsey? Here is an explanation.
We are using a modified version of a "capture-mark-recapture" study, which usually means catching a sample of an animal population, marking them with a tag and then re-catching some animals again later to see how many tagged and untagged individuals you find in the second round. In our study, we will not be catching or tagging any hedgehogs, just asking you if you think they are the same hedgehogs coming back to your garden in each round. In some cases this might be easy, for example, if they have coloured paint on their spines from a rescue centre or if they have blonde spines. In other cases, we may have to judge purely on size and any photos you manage to take of them. This is why we would like all of our volunteers to do their hedgehog watching on the same night if at all possible as it means we are less likely to get the same hedgehog popping up in different gardens.
We will then take all of your observations and plug them into an equation a bit like this to work out an estimate for the total population of hedgehogs in Guernsey:
If you would like to learn more about how this type of study typically works, why not check out this BBC bitesize page: https://www.bbc.co.uk/bitesize/guides/zmxbkqt/revision/3