Letter: Further theories on cuckoo decline
A good answer leads to more questions and two of these need to be answered.
Has the crash in the numbers of the British cuckoo been replicated in the other countries of northern Europe, Denmark, Germany, Sweden, etc? Could the decline of the cuckoo be associated with a decline in the numbers of its hosts – the reed warbler in Norfolk or the sedge warbler in Wester Ross? A shortage of suitable hosts would presumably result in fewer breeding opportunities for the cuckoo.
Walter M Stephen, Edinburgh