I chose a beautiful morning for my March Riversearch survey. The sun was shining, and, being a weekday, I had the stretch of river to myself.
It had rained heavily over the weekend, and, as I looked down from the bridge to the meadow, I wasn’t sure I would even be able to get down to the riverside. Once again, a large area had transformed from meadow to pond. But, thanks to my wellies and my intrepid stick, I was able to get through, staying dry and upright.
The river level was high, and the water turbid. Some of the pipes were discharging a bit of liquid into the river, and in one place the flooded field was draining back into the river.
In the wood there were signs of spring. Wild garlic leaves were plentiful, but the flowers weren’t yet out, so their pungent aroma wasn’t noticeable.
The advantage of surveying just after the water level had somewhat receded was that any patches of earth were blank slates. Instead of the usual muddle of prints from dogs and their owners, there was a smooth, soft surface. This enabled me to spot a clear track in the woods following the river bank. What’s less clear is what made it.
Looking at my track id guide, they look to me like large rat prints. But fellow mammal group members think they’re probably mustellid, either mink (which we know are present on this stretch), or, more excitingly, polecat or polecat-ferret. What do you think?
It may only be March, but the hedgehogs are already out and about in my garden. So I thought it was time to dust off the mammal footprint tunnel again. These are simple plastic tunnels that contain some tempting food, inkpads and paper, so when a mammal comes to investigate the food, they leave inky footprints behind. Here’s how to set one up.
A tracking plate (a simple sheet of stiff plastic that you put the bait, ink and paper on, and insert in the tunnel)
Something tasty (see below for some ideas)
Wide masking tape
Black poster paint powder
Two sheets of A4 paper
8 paper clips
Tent pegs to keep the tunnel in place
Assemble your tunnel
If you use a flatpack tunnel of the design recommended by the Mammal Society, all you need to do is fold it out, and insert the tabs into the slot – easy.
Get your tracking plate ready
This involves several stages:
Paper clip a sheet of A4 paper at each end of the tracking plate.
Put two strips of masking tape across the tracking plate, each the distance of just over the length of an A4 sheet of paper from one of the ends of the tracking plate
Mix one part black poster paint powder with two parts vegetable oil (I used sunflower oil), so if forms a smooth black ink. This is safe for mammals to lick off their paws, and stays damp for several nights. 1 teaspoon of powder and 2 of oil will be enough for your tunnel for several nights. If you make up more than that, keep the excess in a sealed jar until you need it
Apply a layer of ‘ink’ to the two strips of masking tape
Site your tunnel
Now pick a good spot to place your tunnel. Next to / under hedges is a good spot (hedgehogs live up to their names), or along a fence or shed, or on the edge of grassland or woodland. I put mine next to a small garden hedge.
Make sure the tunnel is flat on the ground, and use the tent pegs to keep it in place (you’ll need to pierce a hole in the floor of the tunnel for this, but that’s easily done with a pen knife).
Pick your bait
Previously I’ve had good results with dried mealworms that have been soaked in water to rehydrate them. This time I’ve tried experimenting with berry suet pellets (that are sold as bird food), more mealworms, and dried cat food soaked in water. The hedgehogs have hoovered up everything I’ve put out, so I can’t make any recommendations as to which they prefer, but any of those seem to work. You could also try peanuts (of the sort sold as bird food) (I have a nut allergy, so steer clear of these), bits of hotdog sausage, seeds or bits of fruit.
Last year when I was using the tunnel I put the bait directly onto the tracking plate (in the middle, between the two ink pads). The disadvantage of this is that bits of food end up in the ink, which is messy. So this year I’ve taken to putting it in a little ramekin (of the sort posh puddings come in), which has kept things cleaner. The ramekin does tend to get dragged about in the tunnel, but at least I don’t have to pick bits of mealworm from my ink pads.
Insert your tracking plate into the tunnel
Insert your tracking plate (complete with bait) into the tunnel, and you’re all set for the night.
The next morning
Check your tunnel by removing the tracking plate. Hopefully anything that’s been eating your bait will have left inky pawprints on the paper. All you need to do then is work out what sort of pawprints they are. This can be tricky with some species, but hedgehog prints are fairly distinctive.
It turns out that my garden is the exception, rather than the rule. While hedgehogs are regular visitors to my patch, they were found in only 39% of sites surveyed. This is a lower proportion than expected, and is further evidence of the decline in hedgehogs.
The British Hedgehog Preservation Society and the People’s Trust for Endangered Species are now running an even bigger survey using this method, and are looking for volunteers. It’s quick and simple to set up, and can provide some fascinating insights into your nocturnal visitors – why not sign up? Evidence from this larger study may help us to understand why hedgehog numbers are declining, and how we can help them. Go on, give a hog a hand!
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.
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.
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.
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.
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.
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.
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.
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).
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.
Nest boxes and tubes: Monitoring artificial nest boxes and tubes is another way of finding mammals. This technique is particularly useful for dormice.
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…
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.
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?
This is my diary of the wildlife where I live in Oxfordshire, and sometimes the places I visit. I am a 15 year old young naturalist with a passion for British wildlife, especially Badgers and Hares. I have been blogging since May 2013 and you can read my old blog posts at www.appletonwildlifediary.blogspot.co.uk