I've told this story before.
Short version - Quebec City Canada.
Terrible pigeon problem in the old historic tourist part
City attempts to kill off the pigeons.
Animal loonies cry er...fowl.
City capitulates.
Then time goes by, City builds large housing structure for the pigeons.
Feeds them, houses them, cleans the structure, provides nesting material.
Animal loonies applaud City. Pigeons congregate in one spot, but will still flock to tourist parts of town
at their leisure.
Next there are less pigeons.
Year after there are less pigeons.
Animal loonies grow suspicious, but there are no dead pigeons. Food isn't poisonous.
Year after there are no pigeons. Structure is removed by City.
.....City discloses pigeon food laced with birth control.
City wins.