First Egg

It's the 75th anniversary of data collection here in Wytham Woods and I'm pleased to say that the first egg has been laid in my round! This long-term study has been crucial to understanding patterns in ecology and evolution, and a nice demonstration of that is the finding of this first egg on March 30th. Climate change has led to warmer temperatures earlier in the spring, meaning earlier emergence of leaves and earlier caterpillars. This means that if breeding birds continued to raise their young at the same time of year, they would miss the peak of caterpillars when compared to the peak of their chicks' energetic needs – a condition known as trophic mismatch. This means that the birds have also had to shift their breeding season earlier. This can be seen clearly across the 75 years of data collection in Wytham, where when the study started in 1947, egg-laying was almost a month later!