Bird control solutions based on population

Feed: birds find certain areas particularly promising for finding food.
Breeding: birds use these areas for nesting that are protected from weather and predators.

Populations are defined by the level of infestation:

low population = individual birds occasionally roost.
The populated areas are usually high up on a building and thus exposed to the weather. Birds only roost for a short time, relatively insignificant soiling.  

Recommended control systems:
Stainless steel spikes, stainless steel wire systems, Bird Slides, predator cry systems, acoustic pressure systems, predator decoys
Medium population = the same birds remain permanently
The areas are used as vantage points to survey the feeding possibilities. Often the birds are only there at certain times of day (e.g. when a delivery of goods arrives or a feeder comes).
Heavy soiling.

Recommended control systems:
Stainless steel spikes, netting, stainless steel wire systems, introduction of predators, electrical systems, Bird Slides, predator cry systems, acoustic pressure systems, decoys
Heavy population = the birds nest in protected areas of the building
These areas are protected from the weather and predators and are very important for the birds. The animals have often hatched here.
Very heavy soiling. Nests and eggs are found.

Recommended control systems:
Stainless steel spikes, netting, electrical systems, introduction of predators, bird traps and pigeon houses, acoustic pressure systems, flying robots, visual solutions

A population is not static and can change depending on success in finding food and nesting. The number of animals in an area has nothing to do with the population. Two birds breeding in a nest can indicate a heavy population. One hundred birds waiting for feeding on a roof can be a medium population.  

Often it is not possible to directly categorise the degree of infestation. It is often necessary in practice to graduate the levels.