surplus

What are examples of animal species that there are a surplus number of in zoos in either side of the Atlantic? I'm curious because this is how some zoos get the iconic mega fauna animals or animals that people instantly recognize.

BBC Radio 4 are making a programme on the debate around euthanasia of healthy zoo animals, with a focus on the practice in the UK. They are doing background research at this stage, and are looking to speak with people who would be interested in contributing (anonymously or otherwise) to the...