Birds and Life in the City
City life can be stressful for people but what about urban Wildlife? Studies are showing that the creatures who make our cities their home are being deeply affected by the lighting and traffic noise.
Birds are Changing their Tune
Biologist Simon Watt has found that urban birds are developing a higher pitched and faster song because they have to cope with traffic noise. This is happening amongst all species and birds are singing more at night because the lighting is confusing them. They don’t know when they are supposed to be sleeping and this is probably causing stress.
Breeding and Hunting Trends
This behaviour is not an example of evolution in progress, it is merely an acclimatisation to the prevailing conditions. In addition, birds are finding it harder to sense the changing seasons as temperatures are higher in the cities. Pigeons are breeding all year-round and that has meant that more falcons are visiting urban areas in search of prey and are using street lighting to enable them to hunt at night.
Looking on the bright side, wild birds have access to as much food as they can eat in our cities due to the number of households which feed them. Our rubbish is also attracting seagulls to areas of dense population. Landfill attracts seagulls to the extent that, at certain times, there are more of these birds inland than can be found around the coast.
There is even a species of mosquito which only exists around the Tube in London and which has evolved to feed on humans, rats and mice. Lovely!
Urban foxes now have access to an unlimited supply of food in urban areas but often live very short lives rather than the seven years that you would expect as so many are hit and killed by cars.
Blackcaps, a species of warbler that live in Europe, used to migrate to Morocco or southern Spain for the winter. But these birds have now started to come to Britain because of the warmth in the cities and the availability food in gardens. Simon Watt has also noted that this species has evolved to boast longer beaks which help them to retrieve nuts from bird feeders!
Our cities are causing behavioural changes and even an evolutionary shift. It is happening all around us but most people probably haven’t noticed the changes. Life in the city can be so fast-paced that commuters simply don’t have the time to think about the wildlife that shares the streets with them. But it is there and it is being affected by almost every aspect of our lives.