Pied Flycatcher. The Cheat. David Cookson
The Pied Flycatcher (PF) is a bird I've become more familiar with over the past three years, in particular at Barbondale where there has been an upturn in its status and where this year has seen the best breeding season I know of, though the species at this location I'm not fully historically in tune with.
With the successes came the failures at Barbondale and its the latter I'm just as interested in as the former. There are rarely any definitive answers as to why a nest should fail, bad weather, food shortage, nest predation of many kinds including adults taken by predators. But one puzzle to the mystery interests me more than any other, that of the males engagement in polygamy.
The male PF is something of a love rat, handsome yet devious in his ways, he takes up a territory, sings his song to attract a mate who soon takes him on as a suitable partner for the family to be. Before you know it eggs are laid and the female begins to incubate whilst he keeps busy bringing in periodic food offerings to keep her strength up. But its all a sham, he's stopped singing and bringing in the food, and shes looking around to see where he is, but its all fruitless, hes gone and she's left to take on the exhaustive task of being a single parent.
The male PF has been known to have up to three females in a breeding season, and certainly - though it may only be a small element of the males - regularly have two. But the PF's are not alone in this two-timing behaviour, a couple of other well known examples are those of the Dunnock and Swallow whose engagement in this behaviour is an open secret carried out within a commune or colony, but with the PF male, his second partner is probably in some other far corner of the wood, whilst the first one is carrying on the struggle to bring up the young single handed as will his second one in due course.
Pied Flycatcher. The Cheated. Brian Rafferty
So whilst the male PF will always be seen as a smart bird, smart in appearance whilst smart at being a devious two-timing cheat who leaves the female to get on with bringing up the young on her own - failing to do so on occasions - making him a major contributor to nest failure of which - as claimed at the top of the post - there were some at Barbondale this year.