Which four bird species are major hosts of European cuckoos in Britain?

The four major host species for the European cuckoo (Cuculus canorus) in Britain are:

• Meadow pipits (Anthus pratensis)1
• Reed warblers (Acrocephalus scirpaceus)1
• Pied wagtails (Motacilla alba yarrellii)1
• Dunnocks (Prunella modularis)1

These birds are frequently targeted by the common cuckoo, a brood parasite that relies on other species to raise its young. To improve the success of this parasitism, female cuckoos have evolved to produce eggs that mimic the appearance of their host's eggs. While some hosts, such as the reed warbler, meadow pipit, and pied wagtail, have evolved defenses like egg rejection, others like the dunnock currently show fewer defenses, suggesting they may have been targeted by cuckoos more recently.21