Great Tits are Thriving in Warm English Spring

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Note: a friend of mine in England sent me this story earlier today, and said that from the title alone, it was likely the best news he had heard all day. With tongue firmly planted in cheek I agree with him, and did indeed find it to be a fascinating article. Enjoy.

Researchers have discovered that great tits are laying eggs earlier this spring than normal, and attribute this to an earlier abundance of their main food supply, caterpillars. They also point out that the same species in the Netherlands has not adapted to the change as well as their English counterparts, and are trying to understand why.

The research uses a long record of great tits in a breeding site at Wytham Woods near Oxford, where observations began in 1947.

"We think it’s the longest running population study of wild animals anywhere in the world where animals are marked (ringed)," said Ben Sheldon of Oxford University, who led the new research.

"The population contains about 400 breeding pairs, and they produce between them 2,000 or more offspring each year - so over the course of the study about 80,000 birds have been ringed and studied," he told BBC News.

The current work used records going back only to 1961, when a standard methodology was adopted.

Great tits today are laying their eggs about two weeks earlier this year than their ancestors 47 years ago. During the two-week period after hatching, tit chicks consume massive numbers of caterpillars from the winter moth, making the timing of hatching a pressing matter for their survival, as the caterpillars are only available for a short period of time. According to Oxoford University Professor Ben Sheldon, "Great tits have eight or nine babies in a brood, and each of them will eat about 70 caterpillars a day.

The chicks reach full growth within their first two weeks of life.