i have been picking them up periodically for days. i just picked another one up.
any sort of vermin would jump on a sunflower seed. rats, mice, roaches, whatever. the fact that i can spill sunflower seeds on the ground and still pick them up a week or two later tells me there's nothing living in my kitchen, thankfully.
i did spend some time sealing the kitchen up as my first priority, because i knew to. there were certainly roach sacs under the fridge, although i have not seen a single one since i moved in. but that might be what the mouse is eating.
so, i'm going to focus on just sealing up the laundry first and going from there.