If you are aware of pigeons that have died trapped in netting please don't let their death be in vain. Take a photo if you can and write a letter of complaint to the RSPCA, to the local police, to the Council Environmental Health enforcement officer and to those responsible for the netting. The more we write, the more we complain, the more hope there is that organisations will replace their netting or remove it (according to the Pigeon Control Advisory Service - PiCAS - 'Netting should never be repaired due to the fact that the integrity of the system is based on tension – if netting is repaired a weak point is created that will quickly fail and allow birds to gain access. Netting installations must be replaced when damaged.').
If one case was successfully pursued by the RSPCA people would start being more responsible and fewer birds would die this terrible death!