There are some 350 species of water beetle in the UK, and they often relocate from temporary ponds that dry up in summer to deeper, permanent pools. However, how these stocky little insects navigate between water bodies isn’t fully understood.
How do water beetles find new ponds?
It’s not uncommon for individuals to turn up in moth traps on summer nights, suggesting that, like moths, they use the moon as a navigational aid, following its reflection on water surfaces.
Indeed there’s some evidence that water beetles avoid flying on wet nights, perhaps because the increased reflections on damp surfaces heighten the risk of collision. The light-rich environment that humans have created might prove troublesome for water beetles.
Other freshwater invertebrates are also competent aeronauts. Water boatman are particularly adept on the wing, as are backswimmers which flip themselves out of the water, clean their bodies thoroughly and take to the skies with a distinctive hum.
Even water stick insects and water scorpions are able to fly, though they are considerably more begrudging about it.
Discover more fascinating beetle species and facts