Faking your own death in the bird world

[chrisjpainter]

Some unusual research going on here. It suggests some birds use collections of specifically loose, white feathers to simulate a predator attack to stop other birds stealing nest sites.

Birds fake their own death to protect their nests | Natural History Museum (nhm.ac.uk)

The team found nests that were being used by the builders, but had loose down feathers collected in them. They weren't bound up in the nest matrix, so were otherwise useless, but still retained.

Scientists tested motives behind this with different coloured feathers and just white squares (to rule out it being just colour related). Nest squatters took much longer to move in with collected loose white feathers than anything else. In a third of cases, they refused to go in at all. The theory being that collected white feathers look like down feathers plucked after a bird murder.

The species involved in there test were cavity nesters: Blue tits, tree swallows and pied flycatchers.

[Rookandrabbit]

Fascinating I always thought it was for insulation just shows how intelligent animals can be, thanks for sharing,

[chrisjpainter]

21 minutes ago, Rookandrabbit said:

Fascinating I always thought it was for insulation just shows how intelligent animals can be, thanks for sharing,

I think it depends how they're being used. If they're woven into the nest, then they will be insulating as air is trapped and warmed, but crucially retained. But if the feathers are loose, then the trapped air is all too easily replaced by cold air, so they have no insulating properties, so are essentially just taking up nest space - or providing homes for fungal spores or parasites, neither of which would be good for a nest. Most nest builders are fastidious about cleanliness, so the scientists were looking for an explanation as to why some birds kept loose and specifically white feathers. 

[steve s×s]

On 19/11/2021 at 10:54, chrisjpainter said:

Some unusual research going on here. It suggests some birds use collections of specifically loose, white feathers to simulate a predator attack to stop other birds stealing nest sites.

Birds fake their own death to protect their nests | Natural History Museum (nhm.ac.uk)

The team found nests that were being used by the builders, but had loose down feathers collected in them. They weren't bound up in the nest matrix, so were otherwise useless, but still retained.

Scientists tested motives behind this with different coloured feathers and just white squares (to rule out it being just colour related). Nest squatters took much longer to move in with collected loose white feathers than anything else. In a third of cases, they refused to go in at all. The theory being that collected white feathers look like down feathers plucked after a bird murder.

The species involved in there test were cavity nesters: Blue tits, tree swallows and pied flycatchers.

Would this not just attract predators, iam just a simple country boy not a scientist 

[chrisjpainter]

On 03/12/2021 at 17:41, steve s×s said:

Would this not just attract predators, iam just a simple country boy not a scientist 

You raise an interesting point. My guess is that it wouldn't necessarily make a big impact for predators. The three species picked are cavity nesters, so the predators will be exploratory predators, not ones that are cruising opportunists. So, the feathers won't be immediately obvious unless the predator was already in the nest, so either a bit irrelevant if the bird's on the nest or, from the predator's point  of view, it'll look like they were too late and there's no food left - especially in the absence of blood. Also, these are small species and prey for small predators. There is a tendency for small predators to be nervous of prey that was killed by an unknown predator, as they could find themselves on the menu too - or at least killed to remove competition.