How to Sample

Check out the video below to find out how to sample oribatid mites.

Hint

More videos of the soil animal ecology group can be found on Youtube. If you’re a fan of soil animals, check out the webshop of Svenja.

Sampling accessoires

Plastic bag (ordinary bin bag or something similar, medium size, ~10-20 l volume) or box with lid, garden shovel and/or spade.

Habitat of oribatid mites

Litter from this season is not interesting for us, it is too fresh. Oribatid mites prefer the upper humus layers with already decaying organic material, invaded by fungal hyphae. Here they live and feed. This is easy to find in deciduous forests (but coniferous and mixed forests are also full of mites) if you bend down, remove the upper (fresh) litter layer and scratch off the upper humus layer. This often is a mixture of rotten leaves attached to each other by fungal networks. This is what you are looking for. Fresh litter, dry sticks and branches are not needed, remove them as they only take space away. But decaying wood underneath fallen trunks and mosses are also good places to find oribatid mites.

How to sample meadows and grasslands

Oribatid mites also live in disturbed habitats as grasslands. Here you would need a spade to remove the upper 5-10 cm of soil (including plants and roots). Put the cut out soil to the plastic bag or box. Seal the bag or box after you added a label with sampling site information.

In forests, about 1 m² is sufficient enough to collect tons of oribatid mites. In grasslands and meadows about 30-50 cm² is enough. You close the bag and bring it to my office at the Department of Animal Ecology. I will store the bags at a cold and dry place. Oribatid mites are very small and can last for a long time in a plastic bag or box if they have enough to feed on.

What’s the best time to sample oribatid mites?

The best time is in spring and autumn, it is not too warm/cold and fungi are growing everywhere, at least in autumn. Even after longer periods of frost you can collect litter and soil and find oribatid mites, but then the number of species and densities will be strongly reduced. Day- or night-time is irrelevant for oribatid mites, they are always everywhere.

What shall I do with my plastic bag full of „dirt“?

Please put a note into your bag with sampling date, sampling location (closest city or village, or GPS data) and type of habitat (forest, which kind of forest, which trees are dominating? Grassland or meadows – regularly mowed, grazed by which animals?), local garden or park (under which tree was the litter collected?), other locations (any relevant data related to the biotic environment of oribatid mites). You can store the bags at home in your fridge (between 10-16°C), in the basement or garden shed. Any place dry and cool without frost is good.

What happens to my samples?

I will store your samples at an appropriate place. The extraction will start one week before the course starts. Soil samples will be placed into a Kempson Extractor to separate living soil animals from dead organic material.