Believe it or not, quite a lot.
Moths are major bio-indicators and moth biodiversity and habitat biodiversity, or lack of it, are linked. My friend Veronica French recently contributed to a large-scale study of moths for a paper about the relationship between tree biodiversity in forests and arthropod biodiversity (like insects, spiders, etc.), just published in the scientific journal Forest Ecology and Management under the title “Can Mixed Species Stands Enhance Arthropod Diversity in Plantation Forests?”:
Now we are in October there are very few moths and butterflies around, but nevertheless you will see this smallish moth at your windows, the Hebrew Character – Orthosia gothica. It is important to remember that although they might not be on the wing so much, if at all, these species are still going about their lives in the countryside, albeit as caterpillars, or in suspended animation as pupae, which will later hatch out into adult moths.
If you visit the dampl lowland birch woods at this time of year you can see lots of very interesting invertebrates. Here are two worth noting that I recently came across: the first is a caterpillar that stands on its tail-end to imitate a twig. There are many species, and they can be very similar, making identification difficult, but I think this one is the Birch Mocha – Cyclophora albipunctata, which is quite common in Wicklow and sometimes the moth itself comes to window light.
If you look under fallen logs or large rocks in the dampness of the forests (which are usually located on fens) you stand a good chance of seeing large predatory leeches. Known as Horse Leeches – Haemopsis sanguisuga. They are extremely common in Wicklow, and don’t suck human blood, being in fact active predators of small slugs and snails and many other creatures. They do have that typically creepy quality though, shared by all leeches.