Tordove's Avian Dissuader

You touch the ground at the desired location as you finish the spell. Once the spell is set any time a seed or plant eating bird lands within the spell's area of effect there will be a loud popping sound, or a bang, or the sound of a predatory bird or animal that can be heard by any creature within the spell's area of effect. 

The spell will randomly choose a different sound each time it is triggered. The spell cannot be triggered more often than once every 10 minutes. Most common seed or plant eating birds will be deterred by this sound, however smarter birds may learn that the sound does not pose any danger and ignore it.

The spell will automatically end after one year and a day, but can be cast again in the same spot to continue the effect.

This spell is the work of elven professor of agricultural magic Aelrindel Tordove of the Haven Bay school for the pursuit of agricultural and animal husbandry studies.