By Kiersten McKinley
Assistance from private land owners helped create a record breeding season for the nationally critical threatened kakī/black stilt this year, but not before giving DOC’s Twizel staff the run around.
Each year rangers collect kakī eggs from the wild, and up to six captive pairs, for safe incubation at the Captive Breeding Centre in Twizel.
Last spring, when it came time to find nests in the normal riverbed and wetland sites, staff couldn’t find many. Either the population had declined or they had nested elsewhere. Luckily it was the latter: A particular rainy start to the season saw many wet areas and ponds form on private land. These made attractive nesting sites for this threatened wading bird.
“We put the word out that we needed help to locate adult breeding pairs and got a fantastic response. We had one farmer who rang up to say he had found four eggs and he’d wait until we picked them up before moving his sheep into the paddock,” said Biodiversity Ranger Simone Cleland.
“Another farmer spotted a likely nest from the seat of his tractor. He called up straight away so that we could rescue the eggs and he could carry on working!”
“The farmers I dealt with were very in-tune with their environment and knew exactly what birds they were looking at,” said Biodiversity Ranger Cody Thyne.
“Some people have trouble distinguishing kakī from pied stilts or even oystercatchers, but these farmers were extremely observant and reliable informants.”
It wasn’t only farmers that responded to DOC’s request for help. Sam Staley, the caretaker stationed at Lake Tekapo Military Camp, rang up on several occasions during the season to report the location of juvenile kakī.
Soon the eggs were rolling in; 172 all up, and that put extra pressure on Aviculturist Liz Brown and her team at the captive rearing centre.
“We managed to successfully incubate and hatch 134 chicks, of which 125 survived to fledge – well up on our previous best of 111,” says Liz.
Nearly half of all the wild eggs collected over summer came from eight high country stations in the Mackenzie and Waitaki basins. And, while we’ve always had good ongoing communication with these landowners, the cooperation this season has been excellent and we hope to maintain and develop this relationship in the future.
31 of the chicks were released near Tekapo in January, as the capacity of the aviaries to hold birds had been reached. The remainder of the young kakī will be held over winter and released in August this year. If they can survive the first few years then rangers may be collecting their eggs in the future too.