Tag Archives: sealions

Our Far South: from shipwrecks to high seas

Becalmed in Carnley Harbour. Photo Anton van Helden, copyright Te Papa

I awoke to find that the boat had moved over night to the bottom end of the Auckland Islands, into Carnley harbour, with Adams island to our south. Adams island is home to Gibson’s wandering albatross – DNA research is currently being carried out to determine if Gibson’s Albatross is distinct from other wandering albatross species.

We had incredibly calm weather and took a zodiac ride up one of the arms of the misty harbour to visit what was left of the wreck of the Grafton. One of the great tales of survival of early sailing in the our sub-Antarctic seas. The five men aboard set about extending one of their life dingies, they had to even make their own nails! they made a sturdy little craft to take three of them back to New Zealand in search of help for the two men left behind.

Wreck of the Grafton. Photo Anton van Helden, copyright Te Papa.

Now what is left of the Grafton is used primarily as a sealion hangout.

Our investigations on the rocky shore revealed something that surprised me, a spider living in the intertidal zone! I hope that when I get back to Te Papa that my photo will be enough to help Phil Sirvid identify it.

We spent the morning looking at areas within Carnley Harbour, including an area where rata trees were once cut down by the crew of a German merchant vessel at the start of World War Two. They used the wood as fuel to enable their vessel to reach Chile.

Adams Island in fog, Carnley Harbour. Photo Anton van Helden, copyright Te Papa

“Figure of Eight” Island is home to the most southern breeding site for NZ sealions in the Auckland group. Unlike sealions at Sandy Bay on Enderby Island these sealions breed  in the bush on this small flat islet.

It has been a calm sailing so far, and so there has been a chance to give lectures and have debates. The primary one today being about the NZ sealion and their interactions with the commercial fishery for arrow squid. Lots of things may be influencing the decline of the this sealion population, however it seems clear that fisheries are unlikely to be completely blameless in this. Female NZ sealions, have to work very hard to get the food they need to be able to keep themselves in good condition and to pass that on to their dependent pups. The squid fishery coincides with the exact time when female sealions are foraging hardest to meet the demands of supplying milk to their pups. NZ sealion is the only sealion in the world where the survival of females is less than that of males: it is mostly female sealions that historicaly have been caught as by-catch in the squid fishery. Which surely can not help when a population like this is affected by other influences like disease outbreaks and even normal levels of predation.

Sealion Exclusion Devices (SLEDs) have been put in the trawl nets of the fishery. There is much debate about the chances of a sealion surviving being thrown out of a net at 200m depth. the fishing industry claims that they are now not catching any sealions, but perhaps these SLEDs are just removing the evidence of mortality from their catch.

I have been keeping a look out for Whales…you can only see them if you look!

Heading south. Image WWF.

After lunch we set sail out in to the wilds of the Southern Ocean on our way further south to Macquarie Island. I am greatly looking forward to seeing the elephant seals at Macquarie.

Our far South: Return to Enderby

 
 
 
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Sandy Bay, Enderby Is 1995. Photo Anton van Helden, Copyright Te Papa

I visited Enderby in 1995 as part of the DOC Sealion project. The project is still going today. Sadly the most noticeable thing on my return was the much smaller numbers of sealions and pups.

It is very saddening to hear from Louise Chilvers (DOC’s sealion biologist) that the population has decreased by 50% in the last 12 years alone. In part because of disease epidemics, but probably also because of other factors such as fishing and climate change which may be having an impact on these remarkable animals.

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Sea lion pup suckling. Photo Anton van helden. Copyright Te Papa.

New Zealand sealions Phocarctos hookeri, are the deepest diving eared seals in the world. They have been recorded to dive to depths in excess of 700m. They are sadly, now the rarest sealion in the world, with a population of only about 10,000 animals.

 

The island vegetation has recovered however. After the removal of cattle, rabbits and all other mammalian pest species the undergrowth in the southern Rata forests and the tussock fields that ring the island have bounced back vigourously.

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Southern Royal albatross, Auckland Islands. Photo Anton van Helden, copyright Te Papa.

The yellow-eyed penguins seem to be doing well, which is heartening.

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Yelloweyed penguin. Photo Anton van Helden. Copyright Te Papa.

One Southern Right whale was seen, a reminder that in the winter months they come into Port Ross in the Auckland Islands to calve. At nearly 18m these animals feed on tiny swarming crustaceans called Copepods that they sieve through the water with their long baleen.

Right whale, Port Ross, Auckland islands. Image WWF.

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Louise Chilvers and Anton van Helden, Enderby Island.

The Te Papa Fish team will be coming down here in the next week or so to investigate the animals that live deep down in the waters around the island.

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