Te Papa’s curator of terrestrial vertebrates Dr Colin Miskelly tells the sixth part of the unfolding story of the emperor penguin that went where none had gone before (at least in the age of digital media). Colin is a member of the committee advising on the care and rehabilitation of the bird, and told the first five parts of its story in Te Papa blogs posted between 23 June and 22 July.
It’s time to go! After nearly two months in care, a decision has been made on how the emperor penguin will be returned to subantarctic waters. After a satellite tag has been glued to his lower back, he will be placed in a purpose-built crate and loaded on to the NIWA research vessel Tangaroa at its berth in Wellington Harbour, a few kilometres from Wellington Zoo, on 29 August.
The Tangaroa will be undertaking an acoustic survey of southern blue whiting fish stocks in the vicinity of Campbell Island during most of September. Campbell Island is the southernmost of New Zealand’s subantarctic islands; it lies at 52.5 degrees south, approximately 1100 km north of the maximum extent of the Antarctic pack ice. This is at the northern edge of the at-sea range of immature emperor penguins (see blog of 6 July).
During the four or so days that the Tangaroa steams south from Wellington, the penguin will be cared for by Dr Lisa Argilla, veterinary science manager at Wellington Zoo, with assistance from NIWA staff. There will be no room on board for media, and so TV crews will have to say their farewells to the penguin on the wharf on 29 August. The release should be videoed, and we are hoping that Lisa and team will be able to relay the footage via a satellite link.
After his release on about 2 September, we should be able to follow the emperor penguin’s progress on both the Sirtrack and Our Far South websites (see blog of 11 July). I’ll provide URLs in a later blog, once the pages are up and running.
The satellite tag is not a Global Positioning System (GPS) unit. As partially explained on 11 July, the tag works by transmitting a signal every 45 seconds at times of the day when a polar orbiting satellite is passing overhead. In order to get an accurate fix (within a few hundred metres of where the bird is), the satellite needs to pick up four or more signals per pass. If fewer signals are detected, the penguin’s location will be determined with a lower level of accuracy (typically within a few kilometres of the correct position). The Sirtrack team have developed a programme to check the accuracy of the locations, and plot only those that are plausible and sufficiently accurate.
The location data should be accurate enough to tell if the penguin sets foot on any of the island groups in the southern ocean, but not with the level of precision that a more bulky GPS transmitter would provide.
The penguin has been experiencing polar conditions in Wellington, with the heaviest snowfall in decades gracing the city during 14-16 August, only three weeks after the coldest day ever recorded there. While Wellington residents shivered, the cold conditions cooled the small pool in the The Nest Te Kōhanga, the animal hospital at Wellington Zoo, allowing the penguin to have short swims on 25 July, and 14-20 August.
He is in great condition, weighing in at close to 27 kg. Allowing for the sand removed from his stomach and throat, this is about 6 kg more than when he was brought into care. It could be a rude shock for him to return to catching his own food after 2 months of being handfed young salmon!
Previous blogs on this topic:
For later blogs on this bird: