It’s the world’s largest aphid, fiercely guarded by ants and milked like a dairy cow. Now the Giant oak aphid needs your help. This new survey will help us to map where it lives, so that we can discover just how rare it really is.
How to get involved
The best time to see the Giant oak aphid is in August and September. Visit oak woodland and take a close look at trees at the edge of woodland or that stand alone (the aphid doesn’t like the shade). The aphid is only known from fives sites in the UK, with a stronghold in the east of England, particularly the Norfolk Brecks. The aphid has also been found near Colchester and Exeter, and may occur in other areas.
How to identify: The Giant oak aphid is pear-shaped, with an obvious bronze colour. Normally the first evidence of it, and visible from several metres away, are clusters of the Jet black ant gathered around individual aphids. The ants are, as the name suggests, jet black and shine as if polished or painted with gloss paint: if you are unsure, you probably don’t have the right ant. Once the ants have been spotted, closer inspection is required to confirm the presence of the aphid, which is unmistakeable.
It is important to record as many features of the site as possible; if at all possible, photograph the aphid (even a poor photograph at distance would help us to confirm it). Negative records from apparently suitable habitats – i.e. with Jet black ant and English oak – are also important.