Quick Dips

Caution Urged on Fur Seal Cull

Recent findings about the genetics of New Zealand fur seals [Quick Dips, Oct '95] have prompted a group of scientists to call for caution over calls for culling of the animals.

Research on seal DNA by Drs Geoff Chambers, Scott Baker and Gina Lento of Victoria University's Institute of Molecular Systematics at Victoria University in Wellington indicates the New Zealand fur seal population may consist of two sub-species which are genetically very different, approaching the amount of genetic difference reported for separate species in other animals. They fear that culling could inadvertently reduce the numbers of a relatively rare sub-species.

Further evidence for the existence of two sub-species has come from Australian research showing that there are two different head shapes among the fur seals. The rarer of the two appears to be based on sub-Antarctic Snares Island and is also found on the east and west coasts of New Zealand and, in smaller numbers, around Tasmania.

While the biological picture is not entirely clear, Chambers and his colleagues believe that the two groups of fur seals began mixing after sealing exploitation of the early 1800s reduced the animals to small, isolated populations. Now the two types of fur seals may be hybridising and are difficult to distinguish from appearance alone.

"Despite years of protection, the New Zealand fur seal population is still only moderate in size... Recognising the very real possibility of a rare New Zealand fur seal sub-species, and consequently managing the entire population in respect of genetic differences...would be an exemplary step toward protecting New Zealand's vulnerable biodiversity," says Lento.