is destroying rooks nests and shooting them in April illegal

I have had recent telephone calls from very upset residents of our village.

In our villages church grave yard we have a rookery, but apparently last week someone was in the church yard shooting the rooks and destroying the nests with a large pole.

I presume he was asked by the church to do this as surley he would not do it by his own valition.

I wanted to know therefore if this is illegal and also shooting in what is a place where the public go?

If it is illegal what course ok action should residents take?