DOG walkers on Whitchurch Down have been warned to be on the alert after a pet was menaced by a small flock of birds this week. Patricia Elson, who lives nearby, was walking her dog, Thomas, on the Downs early in the morning last Wednesday when the birds, believed to be either jackdaws, rooks or crows, swooped down to harrass the animal. Mrs Elson, a pensioner, said she was very concerned for the safety of seven year old Thomas as one bird in particular persistently tried to attack him. She said: 'I haven't experienced anything like it before. The poor dog was running around in all directions to get away but the bird was persistent. At one stage I had to use my hand to shoo it away from the dog. It was quite frightening.' Mrs Elson said she wanted, through the Times, just to warn dog owners to be alert of the danger.