DEAR Mr Freethy, I thought that you would be interested in a phenomena we have in our school grounds.

In the spring of 1999 two of our resident crows produced one white offspring. It stayed with its parents until the breeding season of 2000 and since then has been seen by one of our staff in the Chatburn quarry area.

However, this spring what do we get but two white crows. They are still with their parents feeding happily and have no trouble from other birds.

We watched them from fledglings and they are not albino but have black bills and feet. Obviously some sort of a genetic rarity but we have noticed other crows with pale flight feathers as well.

WIN FRANKLAND, Director of Studies, Moorland School, Clitheroe. RON'S REPLY A FEW years ago albinos and partial albinos were regarded as a rarity. They are still far from common and the fact that there are more sightings these days probably means that more people enjoy natural history as a hobby and therefore there are more observers to spot these things.

The study of genetics is advancing rapidly and it would be a useful study for some university worker to examine the problems associated not only with albinum but also with other colour variants.

Around the Chatburn area for example there are a number of all black rabbits. These are referred to as the melanistic form and there is not enough information about the genetics of these forms.

In our spy column I would be interested to have information about albinos and melanistic creatures. A couple of years ago the Evening Telegraph covered a story of an all white house sparrow.

Finally, I will let Win Frankland know that I intend to visit the Moorland school. Perhaps some of the students there can help me to produce a bird survey of the area.