Dragons of the Third Age

[Halbarad]

The 'cold-drakes' of the Grey Mountains are even more myaterious. There is firstly the fact that we don't know what a cold-drake was; was it a dragon that breathed freezing air instead of burning?

"Cold" refers to a dragon or drake that was not firebreathing, rather than a cold-breathing dragon.

Also:

"550-597. The dates of 'the last war of the Elder Days' were changed to 545-587, and after the last words of the original entry the following was added: 'Ancalagon is cast down by Earendil and all save two of the Dragons are destroyed.'" (HoME XI, 3, V)

I don't think that this above reference means that all save two of all of the dragons in their various forms were destroyed, rather that all save two of the great dragons were. Lesser dragons or drakes that could (arguably) breed with the two survivors may not have been included by Tolkien in this, not being 'true' dragons or whatnot. Following this line of argument further, you could argue that any offspring would have been of a much lesser stature, but still dragon enough for the people of ME to call them dragons, if not the author himself. Statements of characters are not necesarily the voice of the author speaking (I forget the correct terminology for this).

Did dragons even breed? Were they all created? I'm just thinking about the mechanical dragons here- still dragons by definition but unlikely that they ever bred. this would explain why all references were to male dragons.