Following a Department of Conservation prosecution, the owner was also required to make a donation to the New Zealand Sea Lion Trust and apologise to the English tourists who saw the incident and reported it to police.
Doc conservation services manager (Coastal Otago) Dave Agnew said Doc investigated the August incident and found the dog was not under sufficient control as it was witnessed chasing the sea lion from the sand dunes into the ocean where it escaped, apparently unharmed, as far as Doc could determine.
Dogs were allowed on Allans Beach, where the incident happened, but were required to be under the control of the owner at all time.
It was the only publicly accessed beach on the peninsula where dogs were allowed. New Zealand sea lions were a ''critically endangered'' species which were making a slow recovery on Otago Peninsula.
Mr Agnew said uncontrolled dogs posed a significant threat to vulnerable wildlife such as penguins, seals and sea lions, so Doc took incidents such as this one very seriously.
''It is very important for dog owners to act responsibly when exercising their pets in areas where these species occur.''
In Dunedin, the self-proclaimed wildlife capital of New Zealand, vulnerable wildlife could be present anywhere along the coast, so dog owners needed to be vigilant, he said.
Doc had investigated two or three incidents involving dogs and wildlife in the past 12 months. Diversion was offered only case by case.
