Feeding Male Great Tits Makes Lazy Birds Unwilling To Get Up & Sing for a Mate

Who in her right mind would oppose feeding the birds? An evolutionary biology sexuality expert might, based on news of what happens to male great tits, when their stomachs are full.

Valentin Amrhein of the University of Basel, in Switzerland, asked himself if feeding birds is good for them. His study is small — just 28 male great tits (no kidding) living in the suburbs of Oslo in Spring 2007 and observed at dawn three times, with 16-17 days between observations.

The first observation took place in the absence of supplementary food. Immediately afterwards, a feeder was provided within the observed male’s territory. Half of these feeders were kept filled with food, but half remained empty. Full or empty, each feeder was left in place for 16-17 days, at which time a second observation was made and the feeder was removed. The third and final observation was made 17 days after this. via The Economist

When humans wake up to a bucolic big tit chorus, it sounds like every bird is having a great time. In fact, male birds have to get up early, not having eaten anything all night, and expose themselves to rain, sleet, hail, snow and high winds. The great tits are demonstrating their worthiness to females as breeding mats.

You’ve heard that the early bird gets the worm, but he also gets the girl bird.

Dr. Amrhein thought birds fed extra food would be in the front row of the early morning bird song chorous. Quite the opposite occured. Basically the birds fed extra bird seed became lazy louts, refusing to wake up and sing. The effect was sustained even after the food was removed.

Having become couch potatos, the male big tits expressed little concern that the sun was up and they weren’t singing.

Image T.A. Wilkins/ScienceIt’s not the case that big tits are stupid. National Geographic shared the 2008 news that great tits in the UK have moved their egg-laying schedule forward by two weeks, adjusting for global warming.  We have no words on how this spring’s big tits will handle the coldest winter in about 100 years (also tied to global warming.)

Nor do we know if male great tits with brighter breasts — and stronger sperm — were as lazy as less colorful birds fed the bird seed.