First Rain Part II: a Moveable Feast
I am sitting outside in the early morning of a cloudy day, after a long, soaking rain that lasted through the night. Swarms of termites hover over the ground and crawl along the wall. A gecko, normally strictly nocturnal, is dashing from the cover of a window frame to take advantage of this sudden abundance. It seems to know they will be gone soon and this rich feast is too much to ignore, even at the risk of being eaten himself.
Termites are social insects with a caste system. Each colony will have a king and a queen. The queen grows a huge abdomen and pumps out thousands of eggs. The eggs hatch and are divided into workers, soldiers and winged reproductives called alates. The alates have been waiting for the rain.
Termites are essential members of the desert ecosystem. Living underground by the millions, they take the energy and nutrients from dead and decaying vegetable material and redistribute it down into the soil. They do not have a waterproof skin, so they remain underground or build inverted tunnels of chewed cellulose and saliva along the surface of dead grass, sticks and hard surfaces like cement. In this way they search for food without exposing themselves to the dry air. But after a rain, they take advantage of the humidity to spread farther and faster than tunneling would ever allow. Great swarms of alates take to the air, hoping to find a mate and settle on the ground, look for some wood to chew into and start a new colony. Most don’t make it.
The mating swarm of termites is a rich source of food for many desert animals. Bats, dragonflies and birds snatch them from the air. On the ground they are gobbled up by toads, lizards, snakes, mice, skunks, coatis, more birds and a variety of invertebrates such as ant lions, scorpions and spiders. And the timing couldn’t be more perfect.
This sudden burst of available protein and energy will fuel the mad dash that high temperatures, and abundant moisture and sunlight will bring to the desert. For it won’t be long before the ponds dry, the soil bakes hard again, and most life will shut down or go underground until the rains come again, many months from now.