Hello,
The hard white droppings you are seeing is concentrated urates. Normally we see some that are looser and some harder. This is related to kidney issues and the bird may not be drinking enough to make the urates softer. You may want to monitor this very carefully as for changes and make sure the Buderygar is drinking enough. I would like to supply you a site about the differences in droppings and what to watch for. If the drpping seem darker, red or yellow see the Avian Vet immediately.At this point it may be wise to just have an examination if the droppings do not change. Joan
http://www.netpets.org/birds/reference/lafeber/12/interpretation_of_dropping.html
Vet. Tech.
I have worked Dr. Salvatore Zietlin DVM who works with many Avian Species..