The breeding season for toroa at Otago's Pukekura/Taiaroa Head was the most successful on record. Photo / 123rf
By RNZ
The breeding season for toroa – the northern royal albatross – has been the most successful on record at the Otago colony, the Department of Conservation says.
Toroa are one of the largest seabirds in the world, with wingspans up to 3m, and DoC classifies them as “nationally vulnerable”, meaning they are at risk of extinction in the medium term.
While the species also breeds on islands in the remote Chatham Islands archipelago, Otago’s Pukekura/Taiaroa Head is its only mainland breeding colony and the site has been adapted to protect them, even to the extent of installing sprinklers to help cool them down from rising temperatures in the summer.
This year, 38 toroa chicks were successfully raised by birds at the colony and have fledged – grown strong enough to fly – and left the colony, said DoC albatross ranger Sharyn Broni. The next most successful seasons were last year and the year before, when 33 chicks fledged each year.
Albatrosses are capable of flying incredible distances and, after leaving their nests, young albatrosses fly all the way to South America.
While the last of this season’s chicks have just left this week, Broni said trackers attached to some of them showed they were already most of the way across the Pacific.
This year, the Pukekura/Taiaroa Head colony hosted more than 80 breeding pairs of toroa, and Broni said the increase in fledged chicks was due to success hatching eggs in an incubator to keep heat and flies away from them.
“It’s been a fantastic season at Pukekura,” he said. “The weather has been great, with slightly cooler temperatures over summer, so there haven’t been overheating or flystrike issues, which is better for both the birds and rangers.
“The chicks have also needed less supplementary feeding than in past years, which suggests there was plenty of food available for the parents. We even found a 2kg eel next to one nest, which a parent had brought back!
“There were several chicks, however, which lost one or both parents, and required a lot of support from the rangers to ensure they were a healthy weight prior to fledging.”
This was the 10th year the colony ran a round-the-clock livestream, called ‘Royal Cam’, with lenses trained on one chick, as it grew from an egg to a fledging, and millions of views from people all around the world. The stream has ended for the season now, but highlight reels can still be viewed.
“Kaewa, as this year’s Royal Cam chick was named, left the colony on September 17 and is living up to her name, which means to travel or roam,” Bronis said. “Her tracker shows she has flown more than 2800km across the Pacific Ocean.”
However, despite fledging and growing strong enough to leave the nest, one of this year’s clutch had already met a young death.
“Unfortunately, one chick took off successfully, but was found dead at a local beach several days later. We don’t know what the cause was.
“It’s sad, but it’s natural that not all the chicks will be successful, once they leave the colony.”
Sadly, despite the bumper crop of Otago fledglings this year, the toroa population still faces significant pressures, Broni said.
“It’s not such good news for the wider population.
“About 99% of the toroa population breeds on small islands in the Chatham Islands and this is a species that faces a range of threats in the wild.
“One way you can help toroa... is by picking up rubbish, because toroa will mistake plastic in the ocean for food, which can be fatal for the adult or the chick, if rubbish is regurgitated to them.”
Plastics have been found in Otago toroa nests, marking several close calls for chicks, and last year, a chick from the colony died, after plastic blocked its intestinal tract.
The Pukekura/Taiaroa Head colony is run by Te Poari a Pukekura, a partnership between DoC, Te Rūnanga o Ōtākou, Korako Karetai Trust and Dunedin City Council.
Te Poari a Pukekura chair Bill Karaitiana said the iwi had strong, longstanding links to the area, which was a place generations past were born and educated.
“The challenge for Te Poari a Pukekura is to build the body of knowledge about the ocean, the land, and the flora and fauna. The purpose of this process is to better understand the toroa as an indicator of the mauri [life force] of its ecosystem.
“The Department of Conservation has made inroads into gathering this data. Overall, the increase in the health and population of the toroa is a great result, and supported by underlying principles of wairua, whakapapa and mauri.”