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Whenever we put a finger up to the tank he follows it around "waving" his front feet at it. He brings them together at his face and shakes them. It's funny and strange, but I am wondering, is this a sign of aggression, or playfulness? Do you think it bothers him?

[youtube]http://www.youtube.com/watch?v=d7s-XATbxSI[/youtube]

It's called fluttering. Sometimes it's part of a mating ritual (males only) or the start of a territorial issue.

What do you mean by "issue"? Is it something that could get worse? He was doing it before we put him in the new tank, and only when you show one finger. He will follow your hand around without doing it.

No, it's fine unless you have another turtle. If that were the case, then you need to keep a close eye on him.

As long as you have only the one turtle there's nothing to worry about. In your case my guess would be it's simply a dominance/aggression display. The turtle interprets your finger as an interloper who needs to be shown who's boss in the aquarium. Your hand is much bigger and the turtle interprets your hand as boss, hence no display.

Do you handle your turtle much? My experience has been that the more frequently you handle your turtle and s/he gets accustomed your hand and accepts it as something non-threatening. He associates your hand with eating or being petted and talked to. All very pleasant associations. Feeding in a separate container each day is an excellent opportunity to handle your turtle. It also helps keep the main tank clean, since the turtle will also poop in the feeding container. That gives you the additional opportunity to rinse the turtle after eating/pooping, ie more handling, more talking, etc.

If you treat your turtle like a pet, not just a curiosity on display in a tank of water, he will interact with you like a pet and not just a wild animal who fears you.