28th March 2019

The Dark-Edged Bee Fly has reappeared in the garden today. This bee-mimic, with its very fluffy body, long legs and very long proboscis has evolved in an extraordinarily refined way- it has incredible ability to hover, which it does as it sups nectar from the base of the tiny pistil tubes of, here,  Forget-me-nots and Primroses etc. This attractive fly does us absolutely no harm but the females use their flying and hovering skills to extraordinary ends- they hover over the ground, searching for the ground-nests sites of solitary bees, before swooping down and flicking the eggs into the bee’s tiny nest-holes. Not only this, the female has already picked up sand or dust and covered each egg, both in order to camouflage the egg for its arrival in the bee’s nest, but probably also to add weight so it travels through the air more accurately! Once the infiltrator egg hatches, the larvae feeds on the larvae of the bee. This arrangement doesn’t seem to reduce the solitary bee

Dark-edged Bee Fly

Dark-edged Bee Fly

Dark-edged Bee Fly

Dark-edged Bee Fly

population significantly. If you see a Bee Fly in your area you can record it on the Bee Fly Watch survey- just put it in your search engine. Conditions: Sun and cloud. Temperature: Max 14 Min 4 C.

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23rd April 2018

Lots of wondrous Dark-edged Bee Flies in the garden and area at present. These gingery mimics of Bees are completely harmless to us and use their long probosces to sup nectar, often while hovering near the Primroses, Forget-me-nots etc they feed from. However they are harmful to ground-nesting Bumble Bees. Bee Flies roll their eggs in sand or dust, maybe to camouflage them or to make them heavier, fly low over the ground searching out Bumblebee nests, and flick the eggs into the nest- holes, where they hatch and parasitise the Bees’ larvae. You may spot Bee Flies hovering a few feet above the ground, looking out for nests to parasitise, changing direction at vast speeds, only to hover again. Conditions: cooler with cloud and sunny intervals. Temperature: Max 14 Min 10 c.

Dark-edged Bee Fly

Dark-edged Bee Fly

Dark-edged Bee Fly