New study shows risk climate change poses to Wytham great tits

The researchers of the great tit research programme at Wytham Woods have been investigating how the birds depend on the winter supply of moth caterpillars – a key source of food for the parents trying to raise chicks. 

The scientists have built a model that links climate change to food availability.  Their findings are not encouraging for the future of the birds of the Woods. Climate change means spring is starting earlier in the year, which causes the caterpillars to hatch earlier and forces the great tits to bring their yearly activities forward as well, to avoid missing the caterpillars, which they rely on to provide food for their chicks. 

The problem is that there’s a limit to how quickly the birds can adapt by starting their breeding year earlier, and eventually they are likely to get so far out of sync with the seasons that they miss the annual bounty of moth caterpillars. At that point, the model shows that their populations could collapse. 

The research drew on the work of generations of naturalists studying the Woods – great tit monitoring started in 1960 and has continued ever since, producing a unique and invaluable long-term dataset that scientists are still discovering new uses for. 

To find out more, consult the full paper which is available online.