Necrow-philia: Study reveals crows attempt sex with dead birds
Crows have long been known to pay special attention to their dead, often assembling around the body and screeching alarm calls in rowdy gatherings that are commonly referred to as ‘funerals.’
But, every so often, it seems these rituals cross the line into truly bizarre territory.
A team of researchers studying how crows behave in the presence of death have discovered that some birds don’t simply interact with the body – they try to have sex with it.
Kaeli Swift and colleagues at the University of Washington have been studying crows’ behavior for years, helping to unlock some of the secrets behind their unusual death ceremonies.
The team previously hypothesized that crows may surround their dead and make a ruckus as a way to warn others about potential dangers in the area.
But in April 2015, they saw something that left even the seasoned researchers in disbelief.
After noticing a dead crow placed beneath a cherry tree – and neglecting to sound the typical alarm calls – a lone crow ‘drooped its wings, erected its tail’ and began ‘approaching in full strut.’
‘A quick hop, and the live crow mounts our dead one, thrashing in that unmistakable manner’ of copulation, Swift explains in a blog post titled, ‘Putting the “crow” in necrophilia.’
The scene was quickly interrupted by the arrival of another bird, who began making the usual alarm calls and brought on ‘a more typical mobbing scene,’ the researcher explains. For the experts though, the brief exchange spurred a deeper investigation. The casual
observer may not recognize a crow’s mating attempt; the birds use vents beneath their tails to copulate, as opposed to penetrative sex, according to The Atlantic.
But, the researcher told The Atlantic, the bird was ‘thrashing about awkwardly,’ in a clear effort to try and obtain the correct position with the facedown corpse. Following the first sighting, the team carried out experiments with a total of 309 individual pairs of crows, using different stimuli to gauge the motivations behind their behaviour.
This included an unfamiliar dead adult crow, an unfamiliar dead juvenile crow, and a dead pigeon dead squirrel. And, they found that the crows ‘sometimes touch, attack, and even copulate with dead crows,’ according to Swift.
Most often the crows touched the pigeons and squirrels, which were presented as possible food items. In nearly a quarter of cases, however, they were seen to touch the dead crows in some way. ‘We saw that these behaviour could be exploratory, aggressive and in rare cases even sexual (about 4% of crow presentations resulted in attempted copulations), with the latter two behaviours being biased towards the beginning of the breeding season,’ Swift writes. Sexual behavior was commonly linked with the onset of the breeding season.
The team also ran experiments using a life-like crow mount and a dead crow to assess their responses, and concluded the issue ‘doesn’t seem to be that they think it’s alive.’
Given the rarity of the necrophilic encounters, and the fact that these were often coupled with aggression, the researchers suspect some crows essentially get confused by dead birds during the breeding season.