To keep birds from eating grass seeds, place deterrents such as plastic owls and rubber snakes, use noise devices to scare the birds, and cover the top of the seeds with a thin layer of straw. Slowly remove the straw using a rake after germination of the seeds.
Change the positions of deterrents once or twice a week so the birds do not get used to them. Another effective deterrent is a shiny helium balloon tied to a big rock. Additionally, try hanging tin cans or wind chimes to a pole or the branches of a tree.
Brightly colored flags and pinwheels are also effective garden ornaments that can frighten birds. Anything that moves and features bright colors potentially drives away birds. If the deterrents do not work, the next step is to bury the seeds around one-fourth inch below the soil, and then pat them with a shovel.
Use a straw mulch mixture to cover the seeds, and keep them away from the sight of birds. Most birds do not eat straw, although some usually get a few pieces of straw for building nests. If these methods fail, use a plastic tarp to cover the seeds and the ground. Do not use this technique during summer as the heat of plastic tends to hamper the growth of seeds.