About 30 years ago myself & a relative were asked to deal with problem rooks in the grounds of a country house hotel,the rookery was in a stand of pine trees & was well established,growing year upon year until it got too big to ignore,the noise & the amount of cr#p being constantly splattered all over the buildings & guests vehicles got to a level where it was affecting business so action had to be taken,our first outing was in time for the branchers,a good majority of them were dealt with using air rifles,afterwards,any that had made it back into the nests & quite a number of adult birds circling above the trees were dealt with using a Marlin goose gun & Baikal Record cartridges!,the rookery was considerably reduced in size by the end of the day,pollarding trees with a shotgun,sore on the neck & shoulder but bloody effective! 🤣🤣🤣