THE recent letter from Chris Maidstone of Caldicot, regarding songbirds is at best misleading. While I respect his right to have a point of view the facts need a greater understanding.

Firstly to have a healthy population of predators such as the sparrow hawk and peregrine you need to have an ample supply of prey items. To state that the numbers of predators is out of control is wrong. When the numbers of prey items have fallen to a point that there is not enough food about then the numbers of predators will also drop.

During the period when DDT was having such a bad effect on peregrines, the generally accepted numbers of successfully breeding peregrines had fallen to less than 100 pairs. Other species at the top of the food chain were suffering similar problems.

It would be expected that the populations of their prey would increase. This was not the case. The populations of many smaller birds have shown a continued decline in their numbers over many decades.

During the years of the population crash peregrines suffered there were calls from some groups that there were too many peregrines and that numbers should be controlled. These groups still would like to see a reduction in the peregrine populations. To what level, I ask as in the 1950-60's they claimed 100 successful pairs were too many. In many places there is illegal poisoning and shooting of peregrines.

Over many years studies before during and after the use of DDT and other pesticides, the tit population in a wood near Oxford showed that despite the changes in sparrow hawk numbers, the numbers of tits successfully breeding was generally limited by suitable breeding sites, i.e. holes in trees or nest boxes. Predators were having little or no overall effect.

During a study of house sparrows living in urban areas, that have suffered a huge decline in their numbers over recent years, it was found that many newly hatched young were dying in the nest box, from possible starvation.

Although house sparrows mainly eat seed when adult, during the early stages of a sparrow's life the adults feed the young small aphids and insects. The study  noted that many gardens have less greenery in them suitable for aphids etc having been laid down to parking areas and patios and along with chemicals designed to kill these "pests" this has reduced the amount of food for young sparrows.

It should be noted that general loss of suitable habitat is the wider cause of not only songbird decline but many other species of wildlife as well.

The delightful tits, sparrows and other birds that delight so many in our gardens when visiting our bird tables are taking advantage of an unnaturally high amount of food resulting in the same high numbers of birds in a small area. It is only to be expected for a predator to take advantage of this unnatural situation. While during the winter the tits and other song bids will delight in the food we put out for them they too are predators eating caterpillars' of delightful butterflies and moths that dance around our gardens in the summer. – Frank Williams, Lords Hill Close, Coleford.