Thanks to the efforts of the Pomona Island Charitable Trust the island’s Haast tokoeka kiwi are kept safe from predators.Continue Reading...
Museum of New Zealand Te Papa Tongarewa marine mammal expert Anton van Helden’s interest was sparked just before Christmas when I sent him photos of a dead beaked whale washed up south of Haast. From the photos he couldn’t be sure what species it was, but had a hunch that it was something quite rare and special. So my colleague Neil Freer and I headed out to get a skin sample to send up to Auckland University for DNA testing.
The excitement was tinged with sadness, as a local fishing crew at Jackson Bay had tried and failed to save this whale a couple of days before it turned up dead. Early morning on Friday 25th November they spotted a small whale stranded on the rocks in a pool of blood and managed to re-float it. Then on Sunday the Haast school principal Liz Hawker sent this photo of a dog investigating a carcass on the Waiatoto spit.
In order to keep the carcass from disappearing into the Tasman Sea local councillor and farmer Kerry Eggling was enlisted to move it up into the scrub, where it was laid on a sheet of filter cloth to catch any small bones. Then we left it to decompose while we waited for news of the species ID from scientists Rochelle Constantine and Emma Carroll at Auckland University.
Stages of decomposition
Over the next few weeks this 1.4 tonne mass of blubber gradually disintegrated into a pile of bones and gloop.
Then after Christmas we got the news that it was indeed a female True’s beaked whale, a species never before seen in New Zealand or Pacific Ocean waters.
The True’s Beaked Whale is named after F.W. True of the US National Museum, who first scientifically described this species in 1913. Until now, True’s beaked whale was known only from about 20 dead animals and a handful of live sightings, in the southern Indian Ocean and the North Atlantic Ocean.
Beaked whales (known to Maori as hakura) are a group of deep-diving whales that usually live out in the open ocean. They are often hard to see at sea because they spend very little time at the surface and usually stay away from the coast. They mostly feed on squid, but also eat fish, using in-built sonar to find their prey in the dark waters of the deep ocean. Before it died, this True’s Beaked Whale was probably feeding in the deep underwater canyons that come close in to the South Westland coast.
The only teeth these whales have are two tusks at the tip of their lower jaw. Only in the males do these tusks poke out from their gums, and they are probably used to attract females as well as to battle other males. The tusks are not visible in females.
It was important to preserve such a rare find to improve our understanding of these elusive creatures, so DOC marine technical support officer Don Neale, skilled whale dissector Ramari Stewart and Te Runanga o Makaawhio representative Nathanieal Scott all gave up their Waitangi day holiday to recover the skeleton for Te Papa museum.
Ramari carries a lot of experience with the tikanga (practices) and matauranga maori (traditional knowledge) of whale strandings. A lot of the tikanga behind the work helps to ensure the safety of the kaimahi (workers) and a successful result.
The tikanga includes setting out “clean” and “dirty” areas on the site so that the sometimes hazardous paru (muck) is confined to a small area and as few of the kaimahi as necessary.
This was absolutely essential, as the filter sheet hadn’t worked as well as hoped to drain away bodily fluids and the carcass was still pretty gloopy and very, very stinky. Ramari warned that anaerobic bacteria in the carcass can be very hazardous.
Ramari insisted this pool of rotting flesh was the nastiest she had worked with. Even worse than recovering bones from pickled whales buried for up to 15 years! The paru made it very hard to sift out the more delicate bones like small flipper fragments.
When she got into collecting flipper bones from the muck just below the rib cage Ramari was a bit puzzled to find some small bones that didn’t seem to belong. Then all of a sudden we heard her exclaim “now I know what’s going on!” These tiny bones didn’t belong to the dead female after all, we realised that two of these rare True’s beaked whales had perished on the Waiatoto spit. The adult female had been pregnant when she died.
While we were working Ramari called the whale Niho Ngore alluding to the female True’s lack of teeth. Te Runanga o Makaawhio will officially name her at a later date.
Cleaning up the skeleton will take a few more months yet, but when she’s ready Niho Ngore and her baby will be sent with a blessing from Te Runanga o Makaawhio to rest in the nation’s precious collections of biological and cultural treasures at Te Papa Tongarewa. There they will be available for scientists and visitors to find out more about this rare animal and its place in the world’s oceans.
In today’s economic climate it’s getting harder to achieve all the conservation challenges facing us. DOC’s way forward is in developing relationships with communities and businesses to help achieve our conservation goals. So it’s great when local businesses offer a helping hand.
Here in South Westland the Biodiversity Team got a boost when Local Helicopter operator Michael “Clutch” Glynn of Mountain Helicopters donated over $6000 flying time to threatened species protection. Thanks to Clutch’s generosity we’ve been able to improve our knowledge of a recently discovered population of skinks and unearth some rare land leeches on a coastal rock stack.
Last year DOC Marine expert Don Neale made an unexpected discovery of skinks basking on a small, vegetated rock stack during a survey of islands and stacks along the West Coast Tai Poutini coastline. This was a pretty significant find, as the only other lizards known to live on West Coast islands are the endemic Taumaka skink (Oligosoma taumakae) and gecko (Hoplodactylus “Open Bay Islands gecko”). These are two of the rarest lizard species in New Zealand and they’re only found on Taumaka me Popotai (Open Bay Islands).
The Mountain Helicopters donation gave us a chance to get back this summer with lizard expert Marieke Lettink to find out what species these skinks are. They could be related to the Taumaka skink or the cryptic skink (Oligosoma acrinasum) found on the mainland, or maybe we have found a new species altogether….
Getting out there was a bit hairy, as the stacks are very steep and skinny and we were thankful for the skill and experience of pilot Nathan Healey in depositing and removing us safely.
In a bit of a battle of the sexes Marieke and I, pitted our lizard wrangling skills against the boy’s team, Programme Manager Gareth Hopkins and Ranger Jeff Rawles, on a larger neighbouring rock stack. I have to admit the girls had a head start as we already knew there were skinks on our island.
Mostly we caught the skinks using cage traps baited with tinned pear, but Marieke with her lizarding superhero skills caught a few by hand. We got very excited when the boys radioed to say they’d spotted skinks on their stack too!
Although their home is restricted to 2 very small island stacks the population seems to be doing really well. We saw lots of juvenile skinks as well as the adults, so they’re definitely breeding.
Once a skink was caught we weighed and measured it and took diagnostic photos of scale patterns to get an idea of how this population fits into the skink family tree.
Based on physical appearance these skinks look like they are related to Taumaka skinks. There were some differences though, so we’re waiting for the results from analysis of tail tip DNA samples to see if they are the same species.
Given the thriving skink population and the difficulty of access from the shore it’s likely these islands are predator free. The boys ran rodent tracking tunnels overnight and didn’t detect any mice or rats. This is great news! Vulnerable species like lizards don’t have good prospects on the mainland with mice, rats, stoats, cats etc etc…
There was more excitement to come as we settled down in our precarious camps for the evening. As dusk fell hundreds of fairy prions returned to roost, and as we were probably sitting right on top of their houses they tried to roost in our laps and on our heads! While suffering this feathery onslaught Jeff lifted his pack up to find some leeches underneath.
Most leech species live in fresh or saltwater environments, but some are adapted to life out of the water. Very few land leeches have been discovered in New Zealand and with the single exception of a specimen found under a log in Fiordland they have only been observed on islands (Snares, Solander and Taumaka). The Taumaka leech (Hirudobdella antipodium) is only known to live on Taumaka Island and hasn’t been seen since 1995, despite extensive searches. Weka introduced to the island early last century probably eat the leeches and that’s a worry for the survival of this population.
New Zealand’s land leeches are believed to feed on seabird blood, so it’s not surprising that the boys saw them coming out just as the fairy prions came back to roost. Or that Gareth had a couple crawling over his face after evicting a prion from his bivy bag. New Zealand leeches are a bit of a mystery and it’s exciting to think we might have re-discovered the endangered Taumaka leech.
We don’t tend to have spare money floating around to check out new discoveries, so it’s great that Clutch’s generous donation of helicopter time and Nathan’s awesome flying skills made this out of the ordinary trip possible. When people come together with a common vision of protecting our special species and environments we can achieve fantastic results.
For the record the girls won on skinks caught by 21 skinks to 2!