oooh question for you. Over here, when we plant carrots and parsnips and even bean, we were advised by the oldies to use something called "Insectes du sol" to prevent the grains being eaten by insects in the ground before things even rose to the surface. We poohoo'ed the idea the first year, and nothing came up, so we replanted EVERYTHING with it a month later and had bumper crops, so now always use it.
Given that EVERYTHING (except salmon, I found) is cheaper in England, we thought we'd buy similar in England, but found nothing... lots to make your green lawns better, but nothing to stop beasties eating the seeds.
Can I presume you too simply place your seeds into the rut without any defence?!!