This month I've been in Scotland taking part in a golden plover survey at an existing windfarm. My role in the survey is different from normal though, instead of counting birds and recording their movements, I've been asked to carry out a survey of their prey items, specifically invertebrates and especially beetles.
I enjoy invertebrate surveys, but of all of the types of survey work I do, this is the type which I am most selective about and probably turn down more than I actually do. The fact is, invertebrates cover a huge array of orders, e.g. butterflies, dragonflies, bees, wasps, beetles, spiders, woodlice, worms, slugs, mites, ticks, flies, centipedes, millipedes, ants, bugs, harvestmen, springtails, the list goes on, to say nothing of all of the aquatic and marine inverts, in fact invertebrates account for 97% of all animal life on Earth.
Guides and resources to help with the identification to species level within many of these groups are almost non-existent. Even if they are there identification often comes down to microscopic examination of a specimen in the lab or even dissection and they are therefore very time consuming. So unless a client is very specific about what they want, I usually decline because otherwise I can end up doing weeks of work for free or working late into the night to meet some unrealistic deadline.