Whale song recorder floats down to Kapiti
A $7000 device that records blue whale songs has been retrieved off Kapiti Island, after drifting 185km from its Taranaki home.
A six-day recovery mission was launched for the Marine Autonomous Recording Unit (MARU) after it became detached from the seafloor in the South Taranaki Bight.
It was finally recovered by the Kapiti coastguard near ‘‘Hole in the Rock’’, at the north end of Kapiti Island, last Thursday morning.
It was tracked using its inbuilt satellite transmitter, and conditions eventually eased enough for the coastguard to retrieve it.
About the size of a beach ball and weighing about 42 kilograms, it was one of five being used in a joint project involving the Department of Conservation, the Marine Mammal Institute at Oregon State University, and the bioacoustics research programme at Cornell University, New York.
DOC ranger Mike Ogle received a call from Cornell acoustic technician Chris Tessaglia-Hymes to say the hydrophone’s locator had activated, meaning it was on the water’s surface.
‘‘Given the weather, we thought ’This is going to be awkward’ and it certainly was,’’ he said.
The mission was a nail-biter to the end, Ogle said. On Thursday morning the locator suggested the MARU, which consists of a hard drive, protected by a glass sphere and a plastic covering, had smashed on rocks.
However, the device was located a few hundred metres offshore. It has now been taken to DOC’s Takaka office.
The device changed course several times. Initially it looked to be heading to Whanganui, but when Ogle called the coastguard on Wednesday night, it was about 10km off Otaki.
Coastguard spokesman Rob Faulke said the job was unique.
‘‘It’s a one-off really. We do odd things for people sometimes, and this was an odd thing.
‘‘We’re unlikely to be called upon to do something like this again.’’
The project, which began almost a year ago, is to determine how many months of the year blue whales are resident around New Zealand. They are currently classified as migratory by DOC.
The lost device contained about six months of data.
The retrieved audio device from the South Taranaki Bight in a life ring.