Usually people do not like city birds – they are noisy, walk around asking for food, sometimes they even contribute to littering problem. However, some of them perform an important function as well. For example, crows, as a recent research from the University of Exeter in Cornwall has discovered, help keeping our environment free from rotting carcasses.
It does not seem to be a surprise – everyone in an ecosystem has a role. However, crows are often seen in trash cans and one might wonder how they benefit their environment. Scientists used motion activated cameras in and around Falmouth and the University’s Penryn Campus in Cornwall to see who would take care of rat carcasses that they placed around for the experiment.
It turns out that scavenger crows take care of the most (98%) of these rotting rats, with a little help from foxes, magpies, badgers and herring gulls. This is a very important task to fulfil, because otherwise there would be tons of dead animals around. Just imagine, how many smaller or bigger animals live around you and you will understand that someone has to take care of them after their life comes to an end.
Dr Richard Inger, one of the researchers of the study, said: “It’s a bit grizzly but crows and other scavengers, which are often perceived as pests and generally fairly unloved species, are performing a very valuable service. Without these scavengers dead animals would be scattered around our environment rotting and causing a hygiene hazard”.
There have been problems in places where scavengers disappeared because of some reasons in some places in the world. For examples, vulture population in India plummeted massively in the 1990s. Dead animals were taken care of by feral dogs, whose population grew significantly, which caused a huge increase in cases of rabies.
This study may prove an important point. All animals perform a specific function in the ecosystem and we should respect it and protect it. Next time you frown upon seeing a noisy and dirty crow, remember that it deals with most of rotting carcasses in your streets.