Third clutch blurs the line between kiwi breeding seasons
A productive kiwi breeding season (Q4 2022- Q2 2023) in Hawke’s Bay saw a leading conservation trust deliver 96 viable eggs to the National Kiwi Hatchery in Rotorua as part of the national Operation Nest Egg conservation drive, two more than last year’s record.
Kiwi lay eggs in two clutches, typically towards the end of Spring and in late Summer or early Autumn. This season the second clutch was noticeably late and one of the Trust’s kiwi experts, Tamsin Ward-Smith, suspects this may have something to do with Storm Gabrielle and the generally wetter than normal summer.
In another unusual development, three of the Trust’s monitored kiwi had three clutches. One of these birds, Scratch, produced six chicks, the youngest of which hatched on 17 May. Most kiwi are starting to prepare for their first clutches of the new season by then.
“We’re not really sure why there was a third clutch,” Ms Ward-Smith said. “We do know that when conditions are good for kiwi they usually make use of it. It has certainly been significantly wetter and, of course, in the mountainous hinterland our kiwi don’t have to cope with the extreme flooding we’ve seen in the lowlands.”
Juvenile kiwi hatching in forests with no predator protection in place have only a five percent chance of making it to adulthood. The survival rate of crèched kiwi far exceeds this; 79 birds from the 96 eggs (82.3 percent) were returned to the bush after growing to a kilogram in weight in predator-proof enclosures known as kiwi crèches. This is the size they need to be to effectively defend themselves from stoats, one of the worst predators of young kiwi.
The trust uses juvenile kiwi from Maungataniwha eggs to re-stock an adjacent property, Pohokura, mid-way between Taupo and Napier. This supports the long-term goal of the national Kiwi Recovery Plan; to reach 100,000 kiwi by 2030 through growing populations of all kiwi species by at least two percent a year, restoring them to their former distribution and maintaining their genetic diversity.
Chairman Simon Hall said he hoped Pohokura would ultimately help re-populate neighbouring areas with kiwi.
“Just as Maungataniwha can now be the source of kiwi to re-stock Pohokura, so we hope that ultimately Pohokura kiwi will make their way naturally to neighbouring areas such as the Whirinaki Te Pua-a-Tāne Conservation Park, which is also being made safe for them.”
This, along with Maungataniwha, Pohokura, privately-owned Ngatapa Station and the Waipunga Conservation Area, forms a contiguous 100,000 ha swathe of the central North Island where kiwi conservation is a priority.
Mr Hall said the trust’s work with kiwi could not happen without the help and investment from its conservation partners, particularly the Cape Sanctuary, the National Kiwi Hatchery and its funder Ngāi Tahu, the Department of Conservation and Save the Kiwi, the only national charity dedicated to protecting kiwi.
“Kiwi conservation is not just about partnerships, it’s about community,” Mr Hall said. “It’s about friends, neighbours and our volunteers banding together to protect our national icon. Frequently in the dark and the cold and the pouring rain. They do it for love – literally.”
In addition to the Maungataniwha Kiwi Projectthe Trust runs a series of native flora and fauna regeneration projects. These include a drive to increase the wild-grown population of Kakabeak(Clianthus maximus), an extremely rare type of shrub, and there-establishment of native plants and foreston 4,000 hectares currently, or until recently, under pine.
Kiwi expert Tamsin Ward-Smith cradles a young kiwi from the Forest Lifeforce Restoration Trust’s Maungataniwha Kiwi Programme.
Σχόλια