The truth about poo
Editor's note: Chris previously posted this on the Autumnwatch blog but we just couldn't stop him banging on about poo (watch tonight's show and you'll see), so here it is again.
I'm sure that many people will consider what they are about to read as a little quirky if not completely mad. But here goes. Ever since I first started to roam and ramble I've been looking at poo. Not a casual glance or a furtive squint, but a hands-and-knees close-up, full critical examination in terms of colour, size, shape, texture, content and, of course, smell.
There is of course a perfectly rational explanation for this. Poo tells me things. Fundamentally it immediately informs me what has been active in the area.
Some species are nocturnal or incredibly shy or both and thus their very presence is difficult to detect. The otter is an obvious example. Yet otter poo (or spraint) is pretty easy to find if there are otters about and very easy to identify, certainly through smell if the sample is sufficiently fresh. Indeed, on a chilly winter's morning the bitter twang rising from a steaming spraint is a delicious shot in the nasal passages, always a treat to savour.
So otter is easy as are fox, badger, weasel and stoat. All of these have diagnostic aromas despite being variable in terms of their form due to the recently consumed diet. Position is also important, for instance badgers deposit their faeces in pits called 'latrines' which act as territorial boundary markers. Deer are easy too, with a little practice. As are bats, although I'm not any sort of expert when it comes to chiropteran stuff myself.
Bird poo is often a little more tricky than mammal but through direct observation and practice you can get quite close to species specific identification. Narrowing down into groups is a start. Again, as an example, raptor poo or 'mutes' typically have a very thick and plastery white component which when dry is powdery.
Tawny owl mutes often seem to have a yellowy wash, as will kestrels', occasionally perhaps an artefact of their broadly similar diets. More investigation is needed here! Poo produced by the grouse family is really easy to identify as it is produced in neat cylindrical pellets. I'm lucky to have in my collection red and black grouse, ptarmigan and the real prize, capercaillie excrement. Obviously location helps in guaranteeing correct analysis but so does relative diameter, an artefact of the bird's size.
Perhaps my favourite bird poo (and I'm sure many other people's too) is produced by the green woodpecker. Again cylindrical, it can be found on short grassy areas where the birds have been foraging. It is about 6-8mm in diameter and somewhere between 25-35mm in length. Its outer skin is white and the interior, visible at either end, is tan brown and roughly textured, so it can look a bit like a crumpled length of a cigarette.
The real joy of woodpecker poo, however, is picking up a dry length and squashing it in the palm of your hand as this reveals the contents as the bodies of countless ants which the bird had eaten, lots of tiny legs and heads and abdomens. Superb.