Every year, up to 4 billion hoverflies (80 tons in biomass!) migrate from Britain to Europe, providing important pest control by consuming 3–10 trillion aphids, as well as long-range pollen transfer. #Biodiversity
bit.ly/3Vi6LNJ
@KazOhashi_Lab Thank you, Britain!
@herrsaalfeld @KazOhashi_Lab It's both ways: the offspring returns and lays eggs in Britain, to start the cycle again. A great argument in support of (the obvious fact that) Britain being an integral part of the European subcontinent, rather than a separate piece of land.
@herrsaalfeld @KazOhashi_Lab Great point: given this distribution of aphid observations in the whole European continent (including the UK; left), and in the UK alone (right), there are likely far more aphids in the rest of Europe ... there's also far more land area, and I can't be bothered to normalize it, so I'll vaguely gesture at marginally relevant data.
Plots from here, filtering for "Europa" and "United Kingdom" (notice the location filter near the top right under the search box):
https://www.inaturalist.org/taxa/52381-Aphididae
@albertcardona @KazOhashi_Lab I thought so. One way migration would be hard to select for by evolution 🙂. But now to the most important fact, where are most aphids consumed?