Nocturnal Life at East Dartmoor
Did you know that when we go to sleep another world awakens?
When you visit the East Dartmoor National Nature Reserve in the daytime, you can see many different bird species quite easily. Mammals are generally harder to spot because most are nocturnal, meaning they only come out at night. As dusk settles in, these creatures start to emerge and the woods become alive with small and large mammals.
It is always exciting to open the images that have been taken, to see what, if any, creatures have been recorded. Observing these glimpses into an animal’s life, undisturbed by people is completely fascinating. Over the last year, we have recorded lots of different species using a camera trap around the reserve – here are some of our favourites.
A good way to study these animals is to use camera traps. By observing tracks and other signs, we choose places where animals are likely to pass by and set the traps accordingly. The camera senses movement or body temperature and automatically takes a photograph or video without disturbing the animal as it uses infra-red light rather than a flash. Camera traps can be used to confirm the presence of a particular species, which is valuable to know, when conservation work is being done to improve the habitat for that species.
Foxes (Vulpes vulpes) are the size of a small dog and easily recognisable with their russet brown fur and long, bushy tail. They are one of the top predators in the woodland food chain and their prey includes birds, beetles, rabbits, voles and mice as well as fruits like blackberries.
Most foxes have a short life, with few living longer than three years. In Spring, the female gives birth to a litter of four or five cubs in an underground den and they are cared for by both the male and female.
Foxes are most active around dawn and dusk, but you can be lucky and occasionally see them during the day. Foxes and badgers do compete for food, but sometimes they can be found living alongside each other in badger setts.
Signs of foxes on the reserve can be found if you look carefully. Fox poo, known as scat, is often left on prominent places like molehills and rocks. They are twisted and you may be able to see remains of the fox’s food, such as fur and bones.
Roe deer (Capreolus capreolus) is a small to medium sized species of deer and the most commonly found in Britain, mainly living in woods and farmland. They are herbivores, eating tree leaves, herbs and brambles. They are beautiful, shy creatures with bright, reddish-brown fur in summer, which fades to a duller brown in winter and only the male (buck) has small antlers.
The female (doe) will normally give birth to two or three young in late spring and the young (fawns) have spotted fur to camouflage them from predators in the dappled sunlight of the wood. They are left in a sheltered spot whilst the doe goes off to feed, returning to suckle them until they are old enough to forage for themselves.
Although they are more active at night, during the day, particularly at dawn and dusk you may spot the white rump flash of a roe deer as it bounds away through the woods. You can also see their slotted hoof prints on muddy paths.
Otters (Lutra lutra) are another top predator, sinuous, aquatic animals 35 – 55cm long, with dense, brown fur made up of two different layers, which insulates them in cold water. They are very strong, fast swimmers, using their webbed feet and a powerful rudder-like tail to hunt for eels, fish, amphibians and birds.
The reserve is a good habitat with clean rivers, plentiful food and lots of vegetation and tree roots along the bank. Their underground burrows called holts are hidden in the riverbank and this is where the female gives birth to one or two cubs. The cubs are introduced to the water, often reluctantly, learning to swim from about 10 weeks of age and may stay with their mother for up to a year.
Otters are very secretive animals and very difficult to spot even in areas where they are widespread, but you can see their signs quite easily. Along the river bank, look for their droppings called spraints. They leave the spraint in prominent places such as rocks, fallen trees and tree stumps in the river. The spraint is dark, with fish bones often visible and its smoky, jasmine tea-like smell is surprisingly not unpleasant!
Mink (a non-native species) may also be found along the river and their droppings (scat) can be found in similar places. In contrast to the otter’s, mink scat is black, smells distinctly nasty and often contains fur, feathers and bones.
Wood mice (Apodemus sylvaticus) are very common in woodlands and despite their tiny size, show up frequently on camera trap images. Wood mice are about 10cm long, have brownish fur with a paler underbelly, large eyes and ears and a hairless tail. They eat nuts, seeds, fruit and insects. They breed quickly with litters of up to eight young as often as six times a year. The young are independent after three weeks and can breed at two months. Despite this, they do not become too numerous as so many are eaten by predators like owls, stoats and foxes and most do not live longer than a year.
Wood mice usually live in dense undergrowth, so they are hard to spot, but you may find gnawed hazelnut shells which show that they are present.
A bank vole can sometimes be mistaken for a wood mouse, but you can recognise the mouse by its pointed face, large ears and eyes and long tail. A vole has a blunter, rounder face, smaller ears and eyes, and a shorter tail..
In the daytime when you visit the reserve, all of these nocturnal animals will be hidden away in thickets, in holes in trees or underground or lying up in the undergrowth. It is very important to keep your dogs under control so they cannot chase animals. Please do not make too much noise and stick to pathways to avoid disturbing them as they rest. Rubbish can also be a serious hazard as animals may get trapped in plastic bags, cans and jars. If you are picnicking in the woods, please make sure you take any rubbish home safely.
If you would like to discover more about the mammals that live in East Dartmoor National Nature Reserve, we have a self guided walk Tracks and Signs of Woodland Mammals which will tell you about these animals and show the signs you can look out for.
The leaflet can be downloaded here – https://eastdartmoorwoods.org/walking-routes/
Written by Joanna Swift
for more about East Dartmoor please visit https://eastdartmoorwoods.org/