For some Fiordland crested penguins, there's no place like home

Fiordland crested penguin in Milford Sound © Thomas Mattern

NEW ZEALAND – When it comes to exploration and endurance swimming, Fiordland crested penguins at Milford Sound would rather stay at home.

Preliminary results from an investigation of the penguins' behaviour have shown, while West Coast penguins travel up to 100 km from their breeding colonies in search of food, those from Harrison Cove in Milford Sound seldom moved further than 1 km. Only one adventurous bird travelled 9 km to the outer reaches of Milford Sound.

The reason for this – an abundance of available food – could in turn signal a successful breeding season for Fiordland crested penguins, known as Tawaki in Maori, in Milford.

The study was undertaken by the Tawaki Project, a collaboration between the Department of Conservation, University of Otago, Global Penguin Society and West Coast Penguin Trust. With the logistical support of local tourism operator, Southern Discoveries, scientists tracked the foraging movements and diving behaviour of Milford Sound penguins using miniaturised GPS data loggers.

University of Otago scientist Dr Thomas Mattern said, “The Tawaki Project aims to identify sea-based factors that influence the penguins’ foraging and breeding success along the coastlines of South Westland, Fiordland and Stewart Island.”

“It appears the weather phenomenon El Niño has created very unusual oceanic conditions this year which in turn affects tawaki foraging hotspots. The good condition of chicks in Milford Sound point towards a very successful breeding season here, in contrast to comparably low breeding success on the West Coast.”

Local tourism operators have also reported a high number of penguin sightings in Milford Sound this year. This was inadvertently made easier when ten penguins, involved in the Milford Sound study, had their mini GPS loggers fitted using industrial red cloth tape.

“This turned out to be a real asset as it allowed cruise boats and sea kayaking operators to report sightings of birds which substantially augmented the data recorded with the loggers,” Dr Mattern said.

“We are now considering introducing colour coded attachments for next year’s tracking work at Milford Sound. As it turns out, coloured tape opens a whole new way of recording data on penguin distribution – with the help of citizen scientists.”

Fiordland crested penguins are one of three penguin species that breed on the New Zealand mainland. The current population is thought to be between 2500 and 3000 breeding pairs and has been in decline since the 1950s.

Source
Successful breeding season predicted for home-loving penguins [media release], 4 November 2015, Department of Conservation