Academics fear for New Zealand's declining sea lion population after discovering a rare breed of sea lion was "rapidly" driven to extinction after contact with humans on the Chatham Islands, in the 17th century.
An international research team, led by Otago University scientists, proved a new type of sea lion existed 650km east of New Zealand's mainland, but was wiped out 200 years after Polynesian settlement of the island in about 1650.
The study indicated that any hunting rate greater than one sea lion killed by one person a year was enough to wipe out an entire population in 200 years, and the study added to growing evidence that undetected bycatch may be behind the declining sea lion levels in New Zealand.
"Sea lions were not able to withstand even low levels of sustained hunting pressure," said Dr Justin Maxwell, an Otago archaeologist.
"Undetected bycatch may still be driving the decline," said associate professor Bruce Roberston, an Otago sea lion biologist. "Something the Government's recently released sea lion threat management plan (TMP) dismisses."