I have fishing line dangling from a few of my hanging feeders as a House Sparrow deterrent. Otherwise the beasts empty my feeders in just a few days. For whatever reason fishing line terrifies House Sparrows but not the other birds.
One day I noticed a Baltimore Oriole flitting around the feeders yanking on various strands of fishing wire. It’s unusual for me to see orioles in my yard this time of year. And it’s also a bit late in the season for one to be looking for nesting material, so the behavior was a bit odd.
Soon a second oriole showed up and it also joined in the yanking game.
The line is quite strong (and slippery) once knotted so the birds were having a time of it. They eventually got frustrated and flew off.
Just in case they returned and wanted something easier to grab, I went to the garage and cut a few loose strands of fishing line which I intended to attach to one of my bird feeder poles with a strip of Velcro. I hoped to sneak it out there before they returned, but as I was walking toward the feeder, I startled both birds and they took off for good.
I’m still not sure what they were up to.