The population fluctuates because of migration, but there has rarely been the concentration of hoopoes as there is at present. There are various theories as to why this is. One is that air current has influenced their migration. Another is that they are simply more visible than usual. Given the hoopoe's diet, which includes caterpillars, the more of the birds there are, there is greater potential control of the processionary caterpillar.
Manolo Suárez, ornithology coordinator for environmentalists GOB, says that the hoopoe migrates to warmer climes when the cold comes in winter but that it remains all year in certain places; Majorca is one of these. He is unsure if birds which have arrived will stay or will fly north when the spring comes.
As for the hoopoe's greater visibility, it is suggested that this is because there is better feeding to be had on the plain of Majorca than in the Tramuntana Mountains. A number of the birds are evident near Albufera in Muro.
