Blue Tit Populations Closely Linked To Numbers Of Moth Caterpillars

The critical importance of moth caterpillars numbers to the population size of a common insect-eating garden bird, the blue tit, were highlighted in a new study

A Blue Tit, Cyanistes caeruleus, feeding one of her nestlings. GETTY

It’s not news that insects and other invertebrates are essential to the ongoing survival of many bird species, but not all ‘bugs’ are created equal. For example, some birds rely on specific species of invertebrates to trigger and support their annual breeding cycle.

A study was just published that reports that the population dynamics of the blue tit, Cyanistes caeruleus, a common garden songbird in Europe, are influenced by the abundance of moths — a core component of their breeding diet. Basically, when moths are abundant, blue tit populations increase the next spring and summer, suggesting that moth abundance directly affects this bird population. But which moth species are the most important dietary components for blue tits?