How to release rehabilitated and over-wintered hedgehogs back to the wild.
I release hedgehogs back to the wild year round except for in the middle of Winter. To give the hedgehogs the best chance, here are some of the factors I bear in mind when releasing.
It has to be 5 degrees or above at night for at least 5 days in a row after release for them to be able to go free. If it is too cold and frosty, there won’t be enough insects around for them to eat.
I also avoid releasing when there is lots of rain forecast, especially torrential storms – all the available nest sites may be too damp. In Spring, I take my cue from when the wild hedgehogs are up and about and being seen regularly in my garden. In York, this is usually April/May. It is important to remember though that local conditions will vary, especially between the city and countryside so it is wise to check with your local hedgehog rescue and keep an eye on your local weather forecast.
Wherever possible, the hedgehogs are returned to where they came from. They will remember the area and the food sources and nest sites. They can be seriously disadvantaged by being relocated, especially if they were rescued as an adult. Sometimes this isn’t possible though if the area has dangers – for example, if a hedgehog has been attacked by a dog in the garden or if it was found in a pond where the finders will not provide an escape route. I have strict criteria for new sites.
To give them the best start back in the wild, the released hedgehogs are all supported for at least the first few weeks. They are provided with food and water daily and they are given nest boxes filled with hay to give them shelter whilst they seek their own homes. This is particularly important if the hedgehog is going to a new area, because it will not be familiar with the best nesting sites.
It is a bittersweet time because they have been looked after for many months (the shortest stay in rescue is around a month) and I will miss them deeply but it is what hedgehog rescue is all about – getting them back to the wild to play their part in maintaining the wild population. Keeping them too long can cause them to get stressed, particularly males, so as soon as they are fit and well and the temperatures are okay, they are off!
Prior to release, all the rehabilitated hedgehogs are given a final health check. I make sure that they are over 650g with a nice rounded bottom. I will have checked a poo sample in the days and weeks leading up to their release to make sure they are parasite free (internal parasites can build up due to the stress of captivity) and they will have been gaining weight consistently (however, note that they should not be too fat either). Hedgehogs can’t dig in captivity like they would in the wild so some hedgehogs may also need a nail trim if their nails have curled (please seek advice on this as it can be quite difficult to do the first time).
You can read some other recent guidance on releasing over-wintered and rehabilitated hedgehogs back to the wild here.
People often ask me if rehabilitation is successful. Well, I mark them all with a tiny bit of nail varnish which should last at least 12 months. I only use the tiniest bit – sadly many people go overboard with marking hedgehogs – which can leave them vulnerable to predators. I only use green or blue nail varnish. I’ve known of people using red nail varnish but, because it looks like blood, the hedgehogs have ended up being ‘rescued’.
Over the 6 years I have been rescuing, I know that a couple of rehabilitated hedgehogs have had to come back into the rescue because their faded marks are still visible. Beyond the 12-18 months point though is unknown….
Good luck out there hedgehogs!
I run a hedgehog hospital in York. You can read more about how I became a hedgehog rehabilitator here. My work is entirely self-funded and you can also find out how to support my work and about my handmade silver nature jewellery, inspired by nature and wildlife at www.littlesilverhedgehog.etsy.com