Hello,
Like most reptiles dropping the tail is a Defense Mechanism. The tail should grow back without a problem, but it may not look exactly the same as before he dropped it. Just make sure the diet is good and plenty of calcium to prevent MBD. Joan Jav917
Here is a link for you: http://www.repticzone.com//forums/WaterDragons/index.html
Veterinary Technician
I am Vet Tech. for 30+yrs. who works with all animals. I do alot of rescue work with small animals.