Eristalis tenax

Eristalis tenax (Linnaeus, 1758)

Biology & ecology:

The larva is of the ?long-tailed?, semi-aquatic type, living in organically enriched ooze such as the mud fringing eutrophic and/or polluted water bodies, the run-off from farmyard manure heaps, silage and slurry pits, and even exudates from putrefying corpses. When mature, larvae leave to look for somewhere dry, often a little above ground, to pupate. In doing so they may travel tens of metres from the larval habitat and turn up in unusual places. Adults disperse widely and visit a wide range of flowers. Can be abundant in gardens. Adults overwinter (not infrequently in houses), and occasional individuals can be seen during warm spells throughout the winter.

Distribution:

Widespread and very common but seemingly more coastal in northern counties of England and in Scotland. Markedly anthropogenic, a pronounced migrant and with a very long flight period.

Status & conservation:

Occurrence has increased over the past 35 years.

Recorded from 1980 hectads since 1990.