Bug count: On the hunt for the devil's coach horse
11 October 2011 Last updated at 07:48 BST
The Open Air Laboratories project (Opal) is encouraging people to go bug hunting in a bid to find out more about the current state of invertebrates in the UK.
More than 500,000 have been found and reported so far - but they are asking for a final push before winter arrives.
They have published a free guide and app to help people identify the slugs, spiders, and beetles that they see.
Here, Lucy Carter, from the Natural History Museum, reveals the best places to spot an eclectic array of invertebrates - from the leopard slug to the devil's coach horse.