Imagine you are one of the shop owner in this plaza. Then you pay loads of money to control the pigeons and pigeon droppings. Then you ask a Pigeon pest control company to install the ADVANCED spiking system.
After few months, you will see the deterrent system worked around your shop.
Then somebody (like myself) comes along and show you this shot!

Bird Spikes Introduction
Anti-Roosting Bird Spikes prevent pigeons from perching on your property without hurting them. Defender, pigeon spikes are the industry standard method of protecting your property. Pigeon deterrent spikes are recommended by the RSPB (Royal Society for the Protection of Birds) and PICAS (The Pigeon Control AdvisoryService).
This professional quality pigeon deterrent system is now available, direct to the public, in mail order DIY packs and comes with a wonderful free instructional DVD.
Pigeon spikes are simply glued on to any window, pipe or ledge where pigeons sit; the dense pattern of the protruding pins make it impossible for pigeons to land – moving them elsewhere without hurting them. Both the steel and plastic pigeon spike systems are virtually invisible once installed and provide the ultimate pigeon deterrent.