Spotted flycatcher the cuckoo, but became so good at recognising the intruder's eggs that it ceased to be victimised. A contrast to this is the dunnock, which appears to be a recent cuckoo host, since it does not show any egg discrimination. A study conducted at two different locations in southern England found that one third of nests were predated. The Eurasian jay ("Garrulus glandarius") was the most common aerial predator, consuming both eggs and chicks. The domestic cat ("Felis catus") predated a small fraction of the nests. Spotted flycatcher The spotted flycatcher ("Muscicapa striata") is a small passerine bird in the
Common raven Common raven The common raven ("Corvus corax"), also known as the northern raven, is a large all-black passerine bird. Found across the Northern Hemisphere, it is the most widely distributed of all corvids. There are at least eight subspecies with little variation in appearance, although recent research has demonstrated significant genetic differences among populations from various regions. It is one of the two largest corvids, alongside the thick-billed raven, and is possibly the heaviest passerine bird; at maturity, the common raven averages in length and in mass. Common ravens can live up to 21 years in the wild, a lifespan