The mosquito larvae's baleful expressions provoked an urge to tease

Every summer they appear and then suddenly vanish into the abyss of the water butt as I lower the watering can towards its surface: mosquito larvae. This year they seemed later than usual, perhaps because egg-laying by overwintering females was delayed by the cold spring. But now every accumulation of rainwater in the garden, even in the smallest container, has become a seething incubator.

I scooped up some water in a jar, stood it on the greenhouse bench and waited for the larvae to regain their composure. As their violent wriggling subsided, they rose slowly to the surface and hung, head-down, suspended by the breathing siphons on their tails. Their baleful expressions provoked the urge to tantalise; just the gentlest of taps on the glass sent them into a frenzy of convulsions, down to the bottom of the jar. Some had progressed to the next stage, becoming comma-shaped pupae whose breathing tubes resembled devilish little horns on their head. They hung tail-down, tumbling as they dived, reacting even more violently than the larvae.

One – darker than the rest – floated immobile at the surface, tail outstretched. Ten minutes later it was still there, but now a head and feathery antennae had appeared above the water. It seemed to shiver and then a thorax and legs appeared, then the pupa's tail became transparent as the mosquito's abdomen slid out. There was a pause, as if the insect was bracing itself for a final effort before making the transition from water to air. It extended long slender legs, positioned its feet on the water surface, and with one smooth motion stood, loaded with menace, needle-sharp proboscis extended like a dagger.

For now it would feed on plant juices but next spring, if it survives the spiders' webs of autumn and the rigours of winter, it will need a blood meal before laying eggs; probably not from me though, for these are culicine mosquitoes whose victims are usually birds.