Feral pigeons, having adapted so well to urban living, are generally regarded as pests in cities. Most of us probably barely notice them, so ubiquitous are they. Pigeons, however, are more intelligent than you might think – they pass the mirror self-recognition test, for instance, putting them in the same category as apes, dolphins and elephants. They can recognise human faces, identify objects and can distinguish between Monet and Picasso paintings (mind you, honeybees have also been trained to do the latter so perhaps it’s not as impressive a skill …).
Pigeons’ ability to find their way home has been exploited by humans since Roman times. Reuter’s News Agency was established in the mid-1800’s with a flock of 45 pigeons – by using the birds Reuter could send news from Aachen to Brussels more speedily than by train. Second World War bomber crews often carried a pair of pigeons which could be released carrying a message giving their position in the event they were shot down. “Operation Columba” was another war initiative that used pigeons, dropped on small parachutes over occupied Europe, to collect intelligence and spread misinformation.
In the 1970’s and 1980’s pigeons were trained by the US Coast Guard to spot people lost at sea. Three pigeons were carried in an observation bubble below a helicopter, and each could look out of two windows. The birds would alert to red, yellow or orange objects in the water and would peck at a switch in their compartment. If two birds alerted, a light would flash in the cockpit and the human crew would then focus their search area. During training, the pigeons spotted the test targets 90% of the time while the humans noticed the objects less than half the time.
In recent years pigeons have been trained to detect cancers from biopsy images. Individually they achieved a success rate of around 85% but when the birds’ results were combined the accuracy shot up to 99%, as good as a trained pathologist.
It seems there is nothing they can’t turn their little bird brains to!