All calico (tortoiseshell) cats are female??
while the vast majority of calico cats are female, there is the occasional male. However, virtually all of these males are sterile. the calico colour is sex linked. For a cat to be calico it must have two X chromosomes ergo the cat is female. In rare instances however a male calico will be produced. This usually happens because the cat has an extra chromosome. So, instead of him being XY, he is XXY. These cats are known as Kleinfelter males.

* Approximately 1-3,000 calico's are male & out of those only 1-10,000 are fertile.

and yes there are Orange females too! lol