Dave supports biodiversity programmes anywhere between Auckland and the Auckland Islands, but specialises in the Chatham Islands and penguins.
Using a band or ring has been vital to the monitoring and conservation of birds for more than 100 years. Yellow-eyed penguins were first fitted with leg bands as part of a landmark population study by schoolteacher-biologist Lance Richdale in the 1930’s.
Unfortunately, leg bands proved to be difficult to read and also caused some injuries so, by the late 1950’s, flipper bands became the standard for marking penguins.
The current banding programme for yellow-eyed’s started in the 1970’s and has enabled the monitoring of penguin survival (to a ripe old age of 24 years) and allowed researchers to know the age and history of the individuals at the focus of their research.
Flipper bands are not without problems. They decrease the underwater efficiency of the bird and, particularly if poorly fitted or maintained, can cause feather wear and injury. Alternatives to bands have been explored and one under investigation at the moment is the use RFID tags of the same type used in dogs and cats. While safe and long-lasting, they do have the downside of requiring electronic readers to find out if a bird is marked and who it is.
Whichever method used, it is important to ensure that those applying the tag are doing so correctly in order to minimise the risk to the bird and maximise what we learn as a result. Penguin chicks get tagged just before they go to sea and I recently took the opportunity to join DOC staff, Yellow-eyed Penguin Trust and Massey University Veterinary students and oversee the tagging of this season’s batch of chicks on the Otago Peninsula.
Assisted by volunteers willing to crawl through flax, gorse and nettle, we visited several sites, going to nests found earlier in the season, before locating and capturing the chicks. Bags are used to restrain the birds while they get weighed, measured and tagged before being released back at their nest site. The weight tells us how good the food supply is (5-6 kg is the normal range) and measuring the head and feet of the chicks gives us an indication of the sex – the males are slightly larger.
Also along for a day was Jeff Corwin of “Animal Planet” fame, filming for the third series of “Ocean Mysteries”. Jeff, trailed by his camera crew, enthusastically crawled through the shrubbery, helping capture and measure chicks. Later in the day he assisted researcher Dr Thomas Mattern with the retrieval and deployment of GPS/dive loggers attached to the parents of some of the chicks we tagged as part of a long-term project looking at where the birds feed.
The opportunity to assist with this work, and spend a few days on the beautiful Otago Peninsula in no less than spectacular weather, was very much worth the being stung by nettle, scratched by gorse, bitten, beaten and pooped on by penguins.
Since my visit some 57 adult yellow-eyed penguins on the Otago Peninsula have died suddenly, possibly due to a marine biotoxin. Birds found dead on the beach have been identified by their tag, enabling rangers to locate the nest and keep a close eye on their almost-fledged chicks. Understanding how the penguins encountered the bio-toxin will be helped by the GPS and dive logger data.