Not sure how, but it will be some of these guys. Had a lovely dig this afternoon, a light fog set in as the wind died and I was serenaded by a couple of loons. They come down to the coast in the winter as the lakes and ponds freeze up, so nothing unusual about hearing them here, but first time I heard them while clamming...
So are you digging in a mixed bottom?
Most look like them came out of mud but a few look snow white like they were in sand? ?♂️