Keep a close eye on your pond for great diving beetles, which are active from early spring when mating gets under way
PHOTOS: ALAMY/MCPHOTO/ROLF MUELLER; PAUL DEBOIS; GETTY/MARK HORTON
You may spot...
Great diving beetle, Dytiscus marginalis Found
in garden ponds and other bodies of water, this is one of Britain’s largest beetles, with an olive-brown, oval body up to 3cm long. They are easy to spot when they rise to the surface to replenish their air supply, which they store beneath their wings. The larvae are yellow-brown, up to 5cm long and resemble rove beetles swimming through the water. Both the adults and larvae are voracious predators, eating other aquatic insects, tadpoles and small fish.