Termites fly

Most termites spend their whole life walking around in the dark, either in tunnels in their food or in nests and tunnels made of mud and faeces.  A few though, get to grow up like normal insects, developing large gossamer wings and waiting about like paratroopers for the big event.  It is quite an event, often the sky seems filled with fluttering termites.

Amazingly, about a third (or so) of the population fly off this way each year and very, very few survive more than a few days after the flight.  Most get eaten.  Some drown. Like paratroops, some land badly or get blown off course.  The lucky ones find a mate and start a new colony.  That's what it is all about.  The termites could just keep expanding as old colonies, or they could bud-off colonies but there is a clear advantage in starting new colonies with healthy, disease and parasite-free young termites.

Flights of most species occur after midday (why?) and some go on into the early evening.  Some termites, like the Formosan Subterranean Termite and some other Coptotermesare attracted to lights, particulary the daylight-like blue tinge of mercury and fluorescent lights.  That's why in Hawaii, the standard street light is a termite-unfriendly yellow (sodium) light.

Flights usually occur in the warmer months (can be all year in the tropics) when the soil is moist, the wind is almost zero and a falling barometric pressure heralds more rain to follow.  These conditions improve the chances of a successful mating flight and for the subsequent starting colonies to have moisture for their early excavations.

Winged termites (called alates) are packed with all the nutrients they need to start a new colony.  That makes them small packets of highly nutritious food. Many animals take advantage of the flights for a good feed.  Birds are usually the first seen, with odd short flight bursts as they take the insects on the wing.  Ants take a huge proportion, usually cleaning them up in the next few days.  Lizards (particularly geckoes and skinks) are quickly attracted and feast openly. 

If you catch a flying alate (fairly easy to do), you'll notice that the abdomen is quite flat, almost cockroach-like.  This is because they are deliberately dehydrated (less mass to lift for flight).  They'll soon swell up if placed on moist paper, just as they would normally while digging in to moist soil or timber.

Termite flights don't usually involve great distances.  It is quite unusual for a flight to provide mating pairs more than a kilometre from the nests and most termites will alight within a few hundred metres.  Being weak fliers they can't fight a wind and so  the stream of emerging termites is often halted abruptly once the wind speed rises.