I was just at marypole mount which is teeming with piggies. I dispersed some startling fecundity powder and didn't see anything until I moused-over the ground below and a text box told me there was meat, grain, etc. I was able to click and pick it up from there, it just wasn't visible.
edit: I wasn't able to pick up everything. When I hover over the remaining meats and messy fry-ups I'm unable to click them to pick them up.
i.imgur.com/TvgrP.jpg