http://www.snopes.com/photos/tsunami/creature.asp
seems that they are real, but as several people mentioned, they've got nothing to do with the Tsunami.
Also, I don't think the water that washed up on Sumatra ea. would be the water at the bottom near the epicentre... Wouldn't make sense to me, that water just pushed other water around, isn't that how waves work in essence? So that means it's water from the shallow part that really flooded those lands?