We would strongly suggest that you Do Not separate the cob from his current mate. Male swans will go back to the original pen, no matter what. If something were to happen to her, it is doubtful that he will re-pair with another pen. Male swans do not usually re-pair if something happens to their original female mate. Separating the two will cause stress to both which can result in illness, depression and even death.

If you try to introduce another female, he could seriously injure her and even, inadvertently kill her should the injuries be severe.

If the present mate is 19 years of age and still producing cygnets, it means she is healthy and is supposed to be having cygnets. Birds are programmed to have a specific amount of eggs throughout their lives. So, your pen is apparently still within the number of eggs to be produced if she is still having cygnets. Nature and hormones will slow and stop this process when it is time. Healthy swans in a stable safe setting can live for 30 years. So, in this time span, your bird is middle aged.

Again, for the health and well-being of your swan pair, we would suggest that the male and female stay together until their natural demise. The Regal Swan