Took me 3 weeks to figure out why my goldfinches vanished, and now I'm not sure I was right
Back in August I had 6 goldfinches on the nyjer feeder every morning, then one day they were just gone, and it took me 3 weeks of moving the feeder around the yard to realize a neighbor's new outdoor cat was stalking the hedge behind it. I moved everything to the side yard and they came back within 4 days, but here's where I keep going back and forth. Some folks on my local bird page in Dayton say cats aren't the real issue and it's the nyjer going stale in the heat, and honestly I never checked the seed date. So do I trust my own eyes on the cat, or was it moldy seed the whole time? Curious if anyone here has tested one thing at a time instead of changing everything at once like I did.
I used to roll my eyes at the cat blame game, figured it was just an easy excuse when the real problem was dirty feeders. Then my sister in Columbus had the same thing happen with her goldfinches and she set up a cheap trail cam from Harbor Freight, and sure enough there was a tabby sitting in the bushes at 6am every day. Three weeks is a long time to watch, so you probably did see what you saw, and a cat coming back to a spot it already hunted is a hard habit to break. Stale nyjer is real too though, so if you want to be sure, put fresh seed in and leave the feeder where it is for a week before you move anything. That way you test the seed by itself instead of guessing after the fact. My guess is the cat was the big thing and the seed was just along for the ride.