Original Research Article Host-parasite interaction augments climate change effect in an avian brood parasite, the lesser cuckoo Cuculus poliocephalus

摘要

Avian brood parasites such as Cuculus cuckoos are recognized to be affected more severely by the adverse effect of climate change owing to close host-parasite relationships. However, the spatial effect of climate change has rarely been assessed in the avian brood parasite-host system. To test this effect, we predicted the distribution shift of an avian brood parasite, the lesser cuckoo Cuculus poliocephalus and its announced 12 host species according to climate change scenarios. Using species occurrence data (presence-only) and environmental variables obtained from publicly available databases, we developed species distribution models under the current and future climate conditions and then compared how much their ranges and the overlap between the cuckoo and hosts are predicted to change owing to climate change. The amount of suitable habitats for the lesser cuckoo and for most host species was predicted to decrease, all the while the ranges generally shifted northward. Climate change also decreased the amount of overlap between the lesser cuckoo and its hosts. This is a mechanism that may significantly shrink the realised range of the lesser cuckoo and should therefore be taken into account in range projections. These results provide evidence that climate change affects cuckoos not only through altered abiotic factors but also because cuckoos and hosts could react differently to such changes, jeopardizing the ability of parasites to track their climate envelope.