Fill your bird feeders and top up your fat ball dispensers, it’s time for the RSPB’s Big Garden Bird Watch again. This weekend the nation will spend an hour watching the birds in our gardens and parks, jotting down what we see. Last year half a million of us saw over eight and a half million birds. This morning I made a cup of tea, drew a chair up to the window and decided to have a dummy run ahead of the official count. As though guessing what I was up to, the first birds to appear were house sparrows, last year’s most common sighting. With gusto they set about the sunflower hearts. Less than a minute later, last year’s bronze medallist showed – the blackbird’s yellow beak flickered in the winter hedge like a flame. Not to be outdone, a loud bickering