Lucy takes one top off herself and Bunya & Ethel kinda' bully off another together. Ethel knows if she sticks close, she can get in for a treat after the other two do (sometimes before).
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| This happens about 13 seconds in - all 3 chewing together in the same pose. |
After they open the first two tops, Lucy looks like she's trying to figure a way to get around Ethel and Bunya and get to the third. However, she gets discouraged and hops back into their pen for a drink of water. When Lucy is not actively seeking treats, Bunya must figure there's none to be had.
But after Bunya and Lucy leave, Ethel knows there're more treats. She just does not quite know the combination. She scratches and nudges until she gets it. Her persistence is rewarded -- she gets all the treats in that last one for herself (if you want to jump ahead, start at about 1 min 33 sec).