Tag Archives: dormice

British Animal Challenge: September and October update

It’s been a while since I wrote the last British Animal Challenge update – back in the long, hot days of August. Now the clocks are about to change, and there’s been a lot of rain, so spending time outdoors is less attractive.

I had hoped to see some new bats and cetaceans in September. Sadly I wasn’t able to identify any new bats, and didn’t see any dolphins or whales. My second attempt at seeing water shrews was unsuccessful. But I did see a stoat.

As the Scots voted ‘no’ to independence, my list hasn’t reduced, but the Jersey Toad has been a small addition.

Other animals I have seen in September and October:

In November I’m hoping to see some harvest mice, and maybe some other small mammals.


Dormice don’t read text books

One of the things I love about monitoring dormice is the way they frequently surprise me. When I first started learning about dormice I was amazed at how much we don’t know about them. Through projects like the National Dormouse Monitoring Programme we’re learning all the time, and it’s great to be able to contribute to this research. Sometimes I think they deliberately set out to prove the textbooks (and me) wrong.

Although October is usually a good month for dormouse monitoring, I wasn’t expecting to see any at the site I helped with this month. No dormice were found in the previous few checks. I was prepared for a pleasant but mouseless scramble round the woods.

I was very happy to be proven wrong. We found six dormice, all of decent weights (although none were very chubby). For some reason, they were all in pairs this time. Dormice aren’t supposed to be social animals, at least when they’re adult and not-breeding. We had a box with a male and a female, and two boxes with two females in. All adults. It’s not like there weren’t plenty of other empty boxes to choose from, if they’d wanted some peace and quiet.

Another thing dormice are supposed to not do is take food into their boxes. Unlike woodmice who cache nuts, dormice tend to eat outside where they find the food. Once again the contrary mice were intent on proving the experts wrong, as we found a nut nibbled by a dormouse in an otherwise empty box. The nibbled nut had since been taken over by a spider.

Apart from the dormice it was a quiet box check. No wood mice, yellow-necked mice or shrews, and of course the birds finished nesting a long time ago.

That may well be my last check for the year, depending on how cold it gets over the next month. The dormice will soon start constructing their hibernation nests, down on the woodland floor (or at least if they’re following the advice of the text books they will). Time for me to start working on something similar?

Dormouse handling

I have been helping out on dormouse box checks for several years now, and for the last few years I have been working towards my license. Dormice are protected by law, and to disturb them in any way you need a license from Natural England. To get this you have to have been trained and have experience of handling dormice of all ages. This can take a while to accumulate if, like me, you mainly do sites with few dormice. Anyway, I now have the necessary experience, but needed to show one of my referees what I am like at handling dormice. I went on a check with him last month, but there were no dormice, so this month I had to try again.

The two sites I visited this month were ones I hadn’t done before. This added an element of treasure hunting / letterboxing / geocaching without gps to the process, trying to find inconspicuous wooden boxes in dense, tangled woodland. Just as well I like a challenge!

The first site was on the edge of a golf course. As well keeping out of the way of golf balls, we also had nettles as tall as my shoulders, brambles and dense, unforgiving blackthorn. The place wasn’t brimming with dormice, so it was a relief when Dave found one sitting on top of its nest in a box. We took the box off the tree, putting it into a large rubble sack. By the time we got the lid of the box off again, the dormouse had disappeared into its nest.

Cautiously I put my fingers into the cavity of the nest, to try to gently coax the mouse out. The nest was wonderfully warm, especially as it was quite a chilly morning, and the mouse was not keen to come out. I could feel some other warm, tiny bodies, and we realised there were young babies (pinkies who had not yet grown fur) with their mum. We didn’t want to disturb them anymore, so quickly and quietly put the box back on the tree and left them to it.

It was lovely finding a young family, but it did mean I still hadn’t had a chance to demonstrate my handling skills. We found no further dormice at that site, although I did come across a nest with three woodmice sitting on top.

So, I had to hope we would find some dormice at the next site. The chances were slim, as last month’s check had found none.

The second site started with some excitement, as the first box contained a pygmy shrew. These are tiny insectivores (smaller than the first joint of my thumb) with long, mobile, Womble-like noses. They have a very fast metabolism which means they need to eat more or less constantly.  It’s not the first time I have found them in dormice boxes. In fact, dormice boxes seem to attract a lot of wildlife, including mice, birds and insects. We often find moths, millipedes, slugs and other invertebrates in them, which is probably what attracts the pygmy shrews.

Most birds have finished nesting now, so dormice have less competition for boxes. Sometimes they build their nests on top of disused bird nests, and sometimes they just make use of the bird’s nest without much alteration. They seem to particularly like wrens’ nests, and who can blame them. Wrens fill the boxes up with moss, creating a large square cavity in the middle, not too dissimilar to a dormouse’s nest (although dormice tend to weave their nests out of strips of honeysuckle bark, leaves and other locally available materials). Wrens also keep their nests much cleaner than other birds (messy bluetits for example). So when I came across a wren’s nest with what looked like mouse droppings on top, I thought it was worth further exploration.

I was right. The nest contained a very lively male, who gave me a perfect opportunity to demonstrate my skills, catching him, sexing and weighing him, then returning him safely to his nest. It’s only my second dormouse of the year, so I was relieved to find I wasn’t too rusty. My referee was happy with how I did, so now I just need to fill in the paperwork!

Dormousing: July

It was hot and humid in the woods on Saturday. There was none of that delicious freshness you usually get in the shade of the trees on a summer day. It felt like a tropical rainforest, and I half expected to hear the cries of chimpanzees.

It was strangely quiet. Perhaps all the birds and animals decided that the best way to deal with the humidity was to stay quiet and still. I must admit that if I hadn’t had a good reason to be out in the woods that morning, I would probably have been sitting near a fan, trying not to do anything.

But each month there is a ten day window to carry out the dormouse box checks, and this was the only day I could do. I was helping to check a site I haven’t done before, which is always a bit of a challenge. When you don’t know where the boxes are it’s a bit like geochaching or letterboxing. Dormice boxes are often away from the beaten track, which means you have to fight your way through brambles, wade through waste high nettles, and scramble over fallen trees.

We didn’t have much luck on this check. No dormice, or signs of new nest building. Just a solitary wood mouse, a wren’s nest, and a couple of bees’ nests. We did glimpse a deer in the distance, but I think everything else was staying hidden away from the heat.

Hopefully I’ll have better luck next time.

12 ways to find mammals

Finding mammals can often be hard – many of them are small, or nocturnal, or both. Last week I got to hear the great ecologist and mammal expert Pat Morris speak to the Surrey Mammal Group. He gave a fascinating (if somewhat macabre at times) talk about how to find mammals. You’re probably familiar with many of the techniques he spoke about, but there were perhaps a few less well-known approaches.

  1. Look in local newspapers for reports of mammal sightings: Local newspapers are often a good source of information about where unusual wildlife have been spotted. Clippings from papers may also be useful to refer back to in years to come. If you’re interested in getting information about the presence of a particular species in your area, talking to the local rag and getting a story in there asking people to report sightings may be very helpful.
  2. Molehill mapping: One of the problems of many survey techniques is that they may reflect where most of your surveyers are active, rather than where the species is most abundant. One way to check you have good coverage of surveyers is to get data on where molehills can be found. As moles are very widely distributed, any gaps in your map are more likely due to lack of surveying, rather than lack of moles, which tells you where you need to do more work.
  3. Droppings: not the pleasantest way to survey for mammals, but once you get your eye in, you can get a good idea of who is around. Many books are too squeamish to show useful photos of droppings for identification, but the Mammal Society have an excellent fold-out guide to British mammal tracks and signs, including some lovely drawings of droppings. It’s a handy size and laminated, so easy to take with you when you’re out and about.

    Water vole droppings
    Water vole droppings –  a good sign these elusive creatures are around
  4. Trails: look out for paths that go beneath low bushes, or up steep hedgebanks – they may well have been made by wildlife (such as badgers, who tend to follow the same route each time). Smaller mammals sometimes create tunnels in long grass. Spotting these trails can then give you an idea of where to search for other signs, such as hairs, pawprints or droppings.
  5. Pawprints / hoofprints: pawprints are another good way of telling if a species is around. Look in soft mud, or after snow, and you could find a surprising number. Sometimes it’s possible to tell from the pawprints whether the animal was running or walking at the time.
    Deer print
    Fallow(?) deer print

    Hedgehog and mouse pawprints
    Pawprints from the mammal tunnel
  6. Hairs: some mammal hairs (like badgers) are quite distinctive, while others can be differentiated with the help of a microscope. Hair tubes can help to get samples from small mammals, while barbed wire fences are a good place to look for hair from larger creatures.
  7. Food remains: It’s sometimes possible to tell what’s eaten something by the food remains. For example, watervoles cut leaves at a neat angle, and often leave short lengths behind uneaten. It’s also possible to tell whether a nut has been nibbled by dormice, other mice, squirrels or bank voles by how the nut has been opened (I must get round to uploading some pictures of this at some point).

    Plant nibbled by water vole
    Plant nibbled by water vole
  8. Traps: trapping using safe traps (eg. longworth traps) is a good way to tell which small mammals are around. Camera traps can also be handy (it’s how we first found out we had hedgehogs and foxes visiting our garden). Watch a video of visitors to our Mammal tunnel with pawprint tracks and camera trap. Also look out for other things which may attract mammals. For example, mice like to shelter beneath left-over roadworks signs and refugia left out for reptiles.
    More slow worms under a corrugated tin refuge
    More slow worms under a corrugated tin refuge


  9. Nest boxes and tubes: Monitoring artificial nest boxes and tubes is another way of finding mammals. This technique is particularly useful for dormice.
  10. Dead bodies: Looking out for dead bodies along roads or in old-fashioned cattle grids can give you a good idea of what’s around, and can be used to monitor change in prevalence over time. A bit grim, but not as grim as point 12…
  11. Owl pellets: Dissecting owl pellets and identifying the bones is a good way of telling what small mammals are around to be eaten. It’s relatively straight-forward to identify whole skulls, and teeth are useful for distinguishing between small mammal species. But first you have to find your owl pellets, which may be tricky. Local birders may be able to help you with this.
  12. Discarded bottles: [warning – don’t read this if you’re squeamish or eating] back in the days when most milk came in glass bottles, a lot were left lying around in hedges, woods and by roads. These glass bottles are very effective traps for small mammals, as they can squeeze in, but the glass sides and angles mean they can’t get back out. As glass stays around for a long-time, there are still lots of bottles out there, many of which are now full of the remains of small mammals that climbed in and couldn’t get back out. Some bottles may have lots of little skeletons in a foul soup of rotted flesh. If you have the stomach for it, identifying these remains can tell you what’s been around since the bottle was discarded. If nothing else, this should serve as a reminder not to drop litter.

I hope this brief summary of Pat’s excellent talk inspires you to get out and about looking for mammals (or signs or mammals). Do you have any other suggestions for approaches to finding mammals?



Dormouse box cleaning

It was lovely to get back to the woods this weekend for my first dormouse session of the year. Box checks naturally come to a halt over winter (an advantage of monitoring an animal that hibernates), so it has been a few months since I last helped at a check.
Most dormice are still hibernating in March, so the focus of Saturday’s session was to clean and repair the boxes, ready for when the dormice emerge. We were a bit worried that we may have left it too late this year, with the warm weather meaning spring seems to be springing earlier than usual. But we didn’t find any dormice, and not many birds have started nesting in the boxes either.
We had a lovely day for it. Quite a contrast to most of the box cleaning sessions that I have done, where my hands become numb from cold within the first few minutes.
While we didn’t find any dormice, there were quite a few wood mice that had to be evicted from the dormice boxes.
Orchids and bluebells have already come up (although not in flower yet),  while primroses and violets were blooming. I was expecting more trees to have come down in the storms, but not many appear to have been damaged,  at least in the parts of the wood we monitor.
Anyway, the boxes are now clean and ready for dormice to occupy. The next check should be exciting.

Highlights of 2013

Well, it’s New Year’s Eve, and like everyone else I am reflecting on the last year. The first part of the year seemed quite hard work, as spring didn’t really seem to spring at all. None of our nest boxes got used, and winter seemed to last until about May, when summer began. The summer was splendid, with lots of sunshine (our solar panels made lots of electricity – it’s so nice getting cheques back from an electricity company!), and the regular company of hedgehogs.

Torpid dormouse
Torpid dormouse

In terms of my year with wildlife, two things really stand out. The first is getting more proficient at handling dormice. They can be surprisingly bouncy (when they’re awake), so getting to handle lots is important to build up the skill to handle them safely without letting them escape. Although this year hasn’t been great for the dormice at the sites I monitor most regularly, I have had the opportunity to help out a couple of times at a site that seems to be teeming with them, which has really helped boost my confidence. A particular delight was getting to handle some mega-cute baby dormice! In terms of my training checklist, I just need to do a nut hunt (for signs of dormice) before I can put in for my license. I have a nut allergy, so I’ll have to do the nut hunt carefully!


The other stand-out wildlife experience of my year was snorkelling with seals at the Isles of Scilly. I wrote a blog post about that, so won’t repeat too much here, other than to say it’s fantastic getting to interact with large, wild creatures who are just as interested in you as you are in them!

In terms of lowlights from the year, news of the decline in barn owl numbers, and the badger cull pilot have both been deeply saddening.

I started my blog at the beginning of September, so don’t have a whole year’s worth of posts to choose from, but here are the top 3 most read posts so far:

  1. Snorkelling with seals (September 21st)
  2. Profile: dormice (the cutest creatures in existence?) (September 17th)
  3. The badger cull: an ‘evidence to policy’ perspective (October 23rd)

And here are my 3 personal favourites (excluding the most visited 3):

  1. Whose pawprints are these? (October 12th)
  2. Hog watching (October 6th)
  3. Only connect: children and nature (October 19th)

What are your wildlife highlights and lowlights of the year? And what are your favourite blog posts of the year?

Profile: dormice (the cutest creatures in existence?)

Torpid dormouse
Torpid dormouse

Hazel dormouse, muscardinus avellenarius

I thought I would start a series of species profiles with the hazel dormouse, as over the last few years I’ve spent quite a bit of time monitoring them, and they are just about the cutest creatures in existence. (If you’re not sure you agree with that, watch this and then tell me what is cuter).

Hazel dormice are small, nocturnal mammals that spend most of their lives up trees, so few people get to see them in the wild. They have quite a varied diet, depending on what’s available at the time, including small insects, pollen, fruit, and nuts. They get the first part of their name from their fondness for hazel nuts. They live in woodlands, and prefer woods with a wide range of trees and a good understory, so food is available for them all the period they are active. Hedges are also important for them, both as a source of food and as a corridor between woodlands.

Dormice seem to enjoy proving dormouse experts wrong, so are sometimes found in unlikely places, including conifer plantations and small strips of wood between the carriageways of the A30.

Hazel dormice are the only dormouse species that is native to the UK, although there are a few rogue glis glis (edible dormice) (a much bigger, more troublesome type) in a small part of the country. (By the way, edible dormice really need to work on their branding – having ‘edible’ as part of your name has got to be bad news… how about adding an ‘in’ to the start of ‘edible’?)

While the dormouse’s range used to cover much of the UK, it is now largely confined to the south of England, with a few small pockets further north. This is thought to be largely due to habitat loss and fragmentation. Because of this, they are protected by legislation that means that you must not catch or disturb dormice without a licence. Any developments that threaten areas where dormice live must put in place mitigation measures to compensate for the damage caused.

Unlike other types of mice, they are not prolific breeders. Mature females will usually have 1 litter of around 4 young per year. Survival of these young depends on enough food being available for them to fatten up before hibernating.

Dormice are not the most active creatures. They spend about 6 months of every year hibernating. Even when they’re not hibernating they go into a state of torpor (very deep sleep) when it is a bit chilly (like the snoring chap in the video).

The People’s Trust for Endangered Species coordinates the National Dormouse Monitoring Programme, which keeps track of how the dormouse population is doing.

If you would like to learn more about these adorable creatures, I can recommend the following:

  • Dormice by Pat Morris: an accessible book focusing on Hazel dormice and edible dormice in Britain.
  • The Hazel Dormouse by Rimvydas Juškaitis & Sven Büchner: a scientific monograph summarising what is known from studies of the hazel dormouse in Europe.

If you would like to help dormice:

  • Sponsor a dormouse: sponsoring a dormouse through Surrey Wildlife Trust will help to pay for new dormice nest boxes and maintain existing ones, which are important for both monitoring the species and giving them suitable nest sites for breeding.