A device for deterring bird intrusion to a space includes permanent magnets mounted on a carrier supported at the space to be protected, the carrier being supported to be rotatable so the that by rotation of same, the bird deterring magnetic field established has intensity and/or orientation change, this with employment of a field with induction of abnormally high gauss level, creates a condition highly physiologically discomforting to a bird encountering the field and such much so that the bird leaves the space area and/or its environs.
