They're not recognizing it as food. It's not enough to thaw them (but make sure they are completely thawed), but they need to be warm. Remember, they have heat pits. I've heard it suggested to warm with a hair dryer or sit on a heating pad. That didn't work for me as through trial and error I discovered my little guy needed it hot - 108 degrees to be exact. He would only take if they prey was 108 degrees, but I had to make it dance on the tongs and then let it drop to the ground. When it hit the ground he struck. Then I learned he would take it straight from the tongs if it was 114 . Picky fella! I warmed his up by sitting on top of his light for a bit and measured with my temp gun. After awhile, he no longer cares that it's that hot. I still warm it up on the light, but now he recognizes it as food.
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