Q: Is it true that purple martins control mosquitoes? I am presently working in Bangladesh. It is the dry season here and mosquitoes are thick as molasses. I hate to think of the rainy season. This is the kind of foreign aid a poor country could really use: a simple, cheap way to improve public health.
A: I’m sorry but the ability of purple martins to control mosquitoes is a myth. According to the American Ornithologists’ Union, a researcher analyzed more than two hundred stomachs of martins collected from February to September throughout the United States and Canada. He reported no mosquitoes in any of the stomachs. Most of the insects found were beetles, flies and butterflies. It makes sense that a voracious bird would prefer insects with some “meat on their bones” rather than tiny mosquitoes.
The situation with bats is much the same. According to Dr. Robert Corrigan, at Pest Control Technology magazine, bats consume all bugs, not bad bugs. They prefer moths and beetles, not midges and mosquitoes. This doesn’t mean we shouldn’t appreciate both creatures and support their conservation. An effective mosquito repellent is still the best option for you and for the good people of Bangladesh.
“The diet of wild bats has been analyzed by dissecting stomach contents or examining fecal pellets. This research has shown that insectivorous bats are opportunistic feeders and that mosquitoes usually make up a very small percentage of their natural diet. For example, a look at fecal pellets for the little brown bat showed 71% small moths, 16.8% spiders and 1.8% mosquitoes (Whitaker and Lawhead, 1992) while the diet of the big brown bat was dominated by beetles and caddisflies (reviewed in Agosta 2002). Providing houses to enhance bat populations is an admirable activity for conservation purposes but it is not likely to help with a mosquito problem.