From: Graeme Backhurst <graeme.backhurst@gmail.com>
Date: 2014-10-17 11:11
Subject: Re: scale of decline of UK migratory birds wintering in Africa
A letter in the August 2014 British Birds 107: 484 from the Rev T. W Gladwin makes a very good point. His letter, entitled Decline in swift populations [in the UK], ends as follows:
"The continuing decrease in insect food availability is surely just as, if not more, important [as a decrease in the number of available nest sites]. When visiting the UK, several of my correspondents from East Africa and France, making comparisons with their local populations, have strongly suggested that the largest cause of declining Swift and other migrant bird populations is not abroad but here in Britain. My response to doubters is to ask: 'When did you last have to wash dead insects off the windscreen of your car?'"
It's commonly believed that the widespread use of insecticides by farmers in the UK has caused, believe it or not, a great reduction in insects and may well be the main reason why so many insectivorous birds have also declined dramatically.
It's also worth pointing out that virtually no British-bred birds come to Kenya.
Graeme Backhurst