Trophy description - Shoot down all the pigeon squadrons.

Trophy - Bronze

You will unlock this trophy in Act VI, Curtain II. Towards the end of the level you will be climbing up the clock tower. At two locations will be a bird house which you need to investigate with Pikarina by pressing R2. A flock of pigeons will remove from each and fly around for a little bit. You must quickly shoot them down by pressing R2 on them with Pikarina. There are 5 pigeons in the first bird house, and 10 in the second. You leave it too long they will disappear so spam R2 as soon as they start flying. the trophy will unlock once you have shot down the last of the pigeons.

See the video below by Wozamil for the exact locations of the bird houses and the pigeons.