The structure and function of drumming in the Middle Spotted Woodpecker Dendrocoptes medius

The disputed occurrence of drumming in Middle Spotted Woodpecker Dendrocoptes medius is due to a lack of sufficient, substantive evidence. In order to obtain a more reliable resource for assessing possible use of drumming in this species, breeding pairs were observed close to potential nest holes in south west France over five years. Drumming was heard in two of the six territories identified and sound recordings were made over four breeding seasons. Analysis of the recorded files consisted of counting and measuring intervals between strikes in all instrumental signals consisting of or containing drumrolls. The results showed that a form of drumming was performed but that it was infrequently produced in a discrete roll. It was usually soft and lacked the regularity of pattern found in the territorial drumrolls of other European woodpeckers. There was also a marked lack of consistency in the amplitude of strikes. As an acoustic signal, this study suggests its principal function to be a communication between partners in relation to the location and construction of a nest site.