The implementation of ABT’s Makarora Braided River Bird Invasive Predator Control Strategy commenced this weekend (7-8 April). A team of amazing volunteers helped deploy a number of invasive mammal traps along 15 km of the Makarora River. Trap locations and deployment was informed by previous braided river bird monitoring undertaken during the 2017/2018 survey season and existing information on the movement of invasive mammalian predators (capable of decimating indigenous bird life) such as stoat, rat and hedgehog.
Volunteers keen to help indigenous wildlife included local Makarora residents, members of Makarora School and nearby residents of Lake Hawea.
The day began with loading up of traps on two boats, one a jet boat with an experienced captain Rod Elliott and partner Jos Mclean. Following a jet boat ride to the far side of the river, volunteers were loaded up with traps for particular designated areas and equipped with a GPS. Traps were then securely staked, marked with coloured triangles and numbered to aid future maintenance.
Following a trap setting demonstration and health and safety talk, traps were baited and sett according to recognised best practice.
The installation and maintenance of the Makarora braided river trapping network aims to help control invasive mammalian predator numbers so that endangered braided river birds such as wrybill, black-fronted tern, banded dotterel and black-billed gull can nest and successfully raise their chicks without being predated. In the longer term a noticeable increase in braided river bird restoration is desired.
Further traps are to be deployed and monthly trap maintenance will be ongoing during the non-breeding season with more frequent checks during the bird nesting season (spring/summer). Volunteers welcome!
Thanks go to all our volunteers. ORC. Also, BRaid for DoC 200 trap supply and production, bait donations from Hawea Flat egg suppliers, discounted radios from Hunting and Fishing Central Otago, waratahs from DoC Wanaka and support from Wilkin River Jets and Mt Albert Station.
ABT’s rock wren transect survey monitoring programme for the 2017/2018 survey season includes the Crucible Basin situated within the Siberia Valley. Monitoring surveys aim to provide an updated baseline on threatened species and allow repeatable monitoring for rock wren within the Makarora catchment to help guide appropriate future conservation management in relation to invasive mammalian predators.
A number of rock wren pairs were recorded present within the bolder-field and moraine habitat and evidence of adults foraging invertebrates for nestlings was noted. During rock wren surveys the Crucible Basin was also noted as an important site for kea as well as rock wren. On both survey occasions seven kea were observed, mainly this years juveniles with their characteristic yellow ceres, eyelids and pale crowns. Kea parents were observed feeding young fledglings regurgitated food and a rock bivi frequented by kea was found close to Lake Crucible.
ABT are collaborating with DoC to extend current mammalian trapping efforts for rock wren within the alpine environment of the Makarora catchment.
All kea records in relation to ABT’s survey and monitoring have been forwarded to the Kea Conservation Trust to help inform a national kea database.
Generally our time at Crucible Basin was positive however, we did note an aerial drone trying to film kea and artificial feeding by visitors. These are two national issues where continued awareness raising is crucial for New Zealand’s threatened species. Image below shows a hunkered down kea looking up at the drone buzzing above whilst others disappeared beneath boulder habitat.
The Aspiring Biodiversity Trust are pleased to report the confirmed presence of rock wren at the north branch of the Wilkin River following the undertaking and setting up of a recent (Jan 2018) transect monitoring survey.
Rock wren Xenicus gilviventris is the only true alpine New Zealand bird species and is currently classed as globally endangered under the International Union for the Conservation of Nature (IUCN). Peter Child’s (1980) work was the first comprehensive bird survey of Mt Aspiring National Park for rock wren.
The main threat to this species is predation from invasive mammals such as stoats and rats now known to be present within alpine environments. The results of the survey will help inform and guide existing and future conservation management for rock wren. Monitoring transects will also be repeated in subsequent years to allow more informed decisions to be made in relation to this indigenous alpine specialist.