I started doing the hair dryer trick and it works wonders for the picky/shy feeders. It helps scent the room and gets their mouths watering.
When you dangle the rat by the scruff, be careful not to bump the snake at all as not to scare them away from the food. I've experienced this a few times and ended up refreezing a rat or tossing it to my boa. Leaving the rat in the tub for a few hours doesn't hurt if they don't take initially as well, I have a handful of snakes that never strike and if I leave the rat in the tub for an hour or 2 it disappears.
Also make sure you get the feeder's temp up above 90 degrees. BPs primarily hunt on scent and heat signature and if the rat is below 90 they may not find it appealing at all, even though they seem interested.
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