Complex sentence: The rediscovery of the takahē caused great public interest in which the New Zealand government took immediate action in closing off a remote part of the Fiordland National Park to prevent the bird from being bothered.
Split into simpler sentences: The rediscovery of the takahē caused great public interest. The New Zealand government took immediate action by closing off a remote part of Fiordland National Park to prevent the birds from being bothered.