Problem getting worse A Bishop Museum entomologist estimated the number of mature midge maggots at 150 million to 200 million at Kealia in 1998 and noted that some 50 million midges emerged in the first week of December 1997. These alien midges, known as Polypedilum nubifer , have bodies about half an inch long and wingspans about a quarter of an inch wide. The smaller ones go through window screens. The larger ones find their way through cracks in sliding glass doors and breaks in window seals. During the rainy season from January through March, millions of them emerge from muddy waters of nearby Kealia National Wildlife Refuge and begin to swarm in the mornings and at sunset.
Midges feed on dead vegetable matter in the pond.
The large swarms that form tall columns are made up of male midges. Scientists say female midges enter the swarm to find a male. They mate in flight and the female flies away to lay her eggs. The eggs become larvae, or bloodworms, that eventually form shells or pupae. After a period of growth, the shells rise to the surface of the water and split, allowing adult midges to take flight.