A male sea lion on has died of exhaustion after a marathon mating session at an zoo in Germany. The mammal, named Mike who was originally from California, was already a father of 12. He passed away yesterday after an extended session with the females at the park in Nuremberg proved too much for his heart. Mike - described as 'good-natured' by the zoo - had mated repeatedly with females Farah, Tiffy and Soda.