Pellets and droppings: observe, don't touch – hygiene first

Owls and birds of prey have no teeth and cannot chew their prey. What cannot be digested collects in the stomach and is regurgitated as a pellet. In owls, bones often remain well preserved because their digestion breaks bones down less than that of raptors such as buzzards or falcons. That is why owl pellets are a small treasure chest for naturalists: skulls and jaws reveal which small mammals live in the area.

Mammal droppings differ by shape, size, content and location. Plant-eaters often leave round or oval pellets, carnivores more sausage-shaped scat with hair, bone fragments or seeds in it. Some species deliberately deposit their droppings at prominent spots – on stones, tree stumps or path junctions – to tell other animals: I am here. Some even use fixed toilet sites, so-called latrines.

Both signs are valuable for tracking because they reveal shy and nocturnal species that you rarely see. Exact identification, however, is often difficult and works best with a field guide and in combination with other signs.

Droppings of foxes, dogs, cats, rodents and other animals can contain parasites and pathogens. In parts of Europe, for example, fox tapeworm is widespread, and its eggs are passed in the droppings. Other pathogens can be inhaled via dust from dried rodent droppings. Which pathogens occur depends on region and species.

This leads to simple rules: never touch droppings with bare hands, do not sniff them and do not crumble dried droppings, so no dust is created. Do not collect fox, dog or cat droppings at all. While working, do not eat, drink or touch your face. Afterwards dispose of the gloves, wash your hands thoroughly with soap and clean work surfaces.

People with a weakened immune system should talk to their doctor first. Local health guidance always takes precedence – this knowledge base does not replace medical advice.

Almost everything you want to know can be found out without touching. First photograph the location with its surroundings: is the pellet lying under a tree, in a barn, in a rock niche? Are the droppings right on top of a stone or at a path junction? The location is often a strong clue in itself.

Then place a tape measure or ruler beside it without touching the find, and photograph it from above. Note shape, length, diameter and visible contents such as hair, bones, feathers, seeds or shiny insect parts. Identify later at home with a field guide rather than taking the find apart on site.

If anything is collected, then only pellets, only with gloves and in a sealed bag. Do not disturb owl roosts and nest sites while doing so: anyone poking around under an occupied roost tree may flush the birds. Many owl species are protected, and local rules take precedence.

Taking apart a pellet is a popular nature-study experiment in schools. For this, pellets from an educational supplier are used that have been treated so that germs are killed. Self-collected, untreated pellets are not suitable for children.

Even with treated pellets: wear gloves, work on a wipeable surface, sort with tweezers and wooden sticks instead of fingers and clean the surface afterwards. The bones can be laid out on dark paper and sorted into skulls, jaws, ribs and leg bones. Children are often amazed at how many small animals are inside a single pellet.

Pellets are not excrement in the strict sense, because they have not passed through the gut. Other birds also produce pellets, for example some gulls, crows and herons; their pellets often contain less well preserved remains. Elbroch and Marks describe pellets as an important bird sign in “Bird Tracks & Sign”, and Elbroch's “Mammal Tracks & Sign” covers mammal droppings. Both books refer to North America, but the principles transfer.

Latrines and prominent dropping sites are, by the way, good spots for a wildlife camera placed at a distance: they show that an animal passes by regularly. That way you learn a lot about an animal without ever getting close to it.