Caring for Pollinators - Bundesamt für Naturschutz

Ssymank Fact sheet pollinators: Flower Flies (Syrphidae, Diptera)
Flower flies and biodiversity of wild plants
The importance of Flower flies for the pollination and fruit set of wild plants is very high: They
are often present in high numbers and the pollen-carrying capacity is medium, to high in species
with dense fur or curled hairs. High local flower constancy due to flower preferences
and local phenology combined with medium to high visitation rates and flight activity may
ensure pollination. Long distance migration in some species makes long distance pollen
transport and fertilization possible. Flower flies visit a large range of different flower families.
Plants visited by flower flies, examples:
Aegopodium podagraria (Apiaceae); Bishop´s Heracleum sphondylium (Apiaceae); Hogweed
Weed
Alliaria petiolata (Brassicaceae); Hedge Garlic Hypericum perforatum (Clusiaceae); St John´s
Wort
Armeria elongata (Plumbaginaceae); Common Knautia arvensis (Dipsacaceae); Blue Buttons
Thrift
Chenopodium album (Chenopodiaceae); Fat Knautia dipsacifolia (Dipsacaceae);
Hen
Cornus sanguinea (Cornaceae); Common Dog- Origanum vulgare (Lamiaceae); Oregano
wood
Crataegus monogyna (Rosaceae); English Haw- Sanicula europaea (Apiaceae); Butterwort
thorn
Filipendula ulmaria (Rosaceae); Meadow Sweet
Specific remarks
• Mobility of species varies greatly, ranging from local territorial behaviour around a
single bush up to regular migration, with some flies capable of crossing the Alps and
covering distances of over 200 km in a few days.
• Many species mimic stinging hymenoptera such as wasps, and bees. Sometimes
mimicry is only in coloration, but other times includes flight sounds and behavioural
mimicry (examples include Volucella bombylans, Temnostoma, Criorhina, and Spilomyia
species).
• The larvae of some phytophagous species feed from the same plants where the
adults collect nectar and pollen (e.g. Cheilosia fasciata and Portevinia maculata on
ramson, Allium ursinum) and show a double relation to these plant species.
See also: contribution Ssymank & Kearns: “Flies –Pollinators on two wings” in this volume.
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