City Birds Are Angrier Than Rural Birds
Well, what do you know, city life turns birds into a**holes. JUST LIKE HUMANS!
No need to head to the movie theatre or download the video game app: Angry Birds can be found right in your backyard this summer–if you live in the suburbs, that is.
Virginia Tech researchers recently found that birds that live in suburban areas exhibit significantly higher levels of territorial aggression than their country counterparts. Once things get a little crowded, the drama dials up. “A possible reason for this is that these birds have less space but better resources to defend,” said Scott Davies of the College of Science. “Living near humans provides better food and shelter, but it also means more competition for these limited resources.”
Along with fellow scientist Kendra Sewall, Davies measured territorial aggression in sparrows at three rural and three urban sites. In these settings, the researchers played a recording of a male song sparrow and observed how the territory-holding birds responded to a simulated intrusion from a neighbour.
Urban and suburban birds showed a higher level of aggression: they approached and remained near the speaker, flapped their wings furiously, engaged in loud singing and then began to produce ‘soft song’ – a term that researchers use to describe the quiet, garbled noise that a bird makes, which is predictive of an impending attack.
Though rural birds still responded to a song intrusion, they did not respond as vigorously. The suburban birds were more territorial, showing that their increased aggression persisted throughout a breeding season.
Human population expansion can be both good and bad for the nature around us. Though many animals avoid habitats that are impacted by humans, some species can adjust and live in suburban and urban habitats. Some even thrive because we are there. But it doesn’t stop them getting all hot under the collar at each other.
Testosterone and population density are the usual predictors for aggression, but can this be compared to the human population? Perhaps. The world population is projected to reach 9.6 billion by 2050, according to the United Nations, increasing by more than 2 billion people. So we should really find out what we need to be ready for. If urban birds are more aggressive in defending their territories, will humans be the same? We will all end up having punch-ups with our neighbours? It’s hard to know. But back to the birds, we need to understand widespread behavioural differences between various species of urban and rural bird populations to get an idea of how urbanisation will affect their survival and diversity in the future.
Says Sewall, “Suburban sprawl is a primary form of human habitat change and though many species can survive in our backyards, their behaviour and physiology may change to cope with shifts in resources and with new disturbances.”
It looks like every species will have to learn to cope with humans and their breeding. Will we all be angry humans as the world population dials up a notch? Perhaps. Let’s get on that colonisation of Mars thing. ASAP.
You might also like
ShareYes, cat owners, it is true. There is now a robot that cleans up cat poop. You get all the fun of being a cat owner without having to touch
Share We have a lot of horsey folk that read the Almanac. And now, you will be glad to know that what you are telling everyone about your horse (that