I have been breeding and keeping coloured canaries for many years
Unfortunately I purchased 8 White Topaz canaries last year and all died except one hen bird.
There was no reason why they died. I even had them in quarantine for one month and they looked very healthy?
However maybe I should have insisted they had been close rung and them I would have known their age
So now I need a cock White Topaz to hopefully start to develop a new line.
(Have a look at my article on line breeding)