Displaying items by tag: Matuku

First recorded booming within the DU Wairio wetland

The spring 2022 survey report compiled by Shane Cotter, a contractor engaged by GWRC.

John Cheyne of Wetlands Works led annual spring surveys for Australasian bittern (matuku, Botaurus poiciloptilus) and spotless crake (pūweto, Zapornia tabuensis) at selected wetlands within Wairarapa Moana between 2012 and 2021. In 2022, John passed this responsibility to me. I conducted the annual spring (October-November) 2022 survey using the same methodology as in previous years so continued comparisons could be made of the annual results.

This year’s survey focused on the core wetlands (Boggy Pond, Matthew’s Lagoon and Wairio wetland) and the northern wetlands (Barton’s Lagoon, Tauherenikau delta, Simmond’s Lagoon, JK Donald Block). Only booming male matuku are surveyed because females are much less vocal and therefore very difficult to detect and monitor. This booming call is associated with males attempting to attract females for breeding. Pūweto were also surveyed at Boggy Pond and Matthew’s Lagoon.

In the 2022 survey, 11 booming male matuku were located at the core wetlands and 12 in the northern wetlands. This is an increase in previous years and a record number at both locations. At the core wetlands, numbers have remained relatively stable at 8-9 birds since 2014 while at the northern wetlands, annual numbers of male matuku has varied between 3-9 birds. Overall, the combined number of booming male matuku at the core and northern wetlands has steadily increased from 10 in 2016, to 16 in 2018, to 18 in 2020, and now 23 birds in 2022. In addition to the 23 male matuku heard booming during the 2022 survey, three other birds were seen, one in Matthew’s Lagoon near Boggy Pond and two in Wairio wetland.

At Boggy Pond, nine pūweto were located, the most in Boggy Pond since 2018 and significantly up on the single individual in 2021. At Matthew’s Lagoon, none were recorded during the kayak survey which has been a regular result there since 2014. While undertaking the matuku survey, four other pūweto were heard calling independently, not in response to playback calls. Two were calling in Matthew’s Lagoon close to each other while at two locations within Wairio wetland, one individual was heard calling. I believe there are more pūweto present than recorded during the pūweto surveys. They have just moved to different areas of the wetland complex outside the pūweto survey routes seeking more suitable habitat.

On-going predator trapping with the regular servicing of traps is essential as several predators were seen dead in traps within days of the traps being serviced and rebaited with fresh bait by the trapping contractor at the core wetlands. These included a weasel and several rats. All traps observed were well set up and maintained, and had good vegetation clearance.

Follow the 'read more' link to view the survey report.

Ducks Unlimited NZ AGM (23 July 2016)

Emma Williams has continued working on the bittern project assisted by me and other volunteers. 

Key points are:

1. Emma graduated with her Doctorate  Degree at Massey University which was based on bittern research. A huge thank you to DU for helping fund a major part of her work to learn more about this iconic critically threatened species.
2. A total of 10 male bitterns (six 2014 and four 2015) were captured at Lake Whatuma and transmitters attached. Of these 10 birds, nine left the lake over summer with one bird remaining on the lake. The bird that remained on the lake was found dead in late April in raupo and cause of death unknown. Four of the birds have returned to the lake in July and one other is being monitored at a  wetland 10kms away. In spite of extensive  searching the location of the remaining four birds is unknown, but it is most likely they will return to the lake in time for spring like birds did last year. The DU funded transmitters have contributed significantly to our much increased knowledge of this secretive bird.
3. Emma travelled to Christchurch earlier this year to place transmitters on two bittern chicks that had been found abandoned not far from Travis wetland on the outskirts of Christchurch. These have been monitored by local people. One bird is still alive near the mouth of the Waimakariri River north of Christchurch and the other was found dead in mid May near the mouth of the Opihi River over 100kms south of Christchurch. This bird was examined and appeared to have died of starvation which is not uncommon overseas with bittern. Very interesting results plotting the movement of this juvenile bird and proves that bittern can move considerable distances.
4. We held a very successful meeting on April 6 for the local Waipukurau community, landowners and Iwi to up-date them on the bittern project. Over 50 people attended and DU received well deserved acknowledgment for their significant contribution to the project.
5. Emma has done no further school talks in the Wairarapa but will complete others this spring organised jointly between her and Gill Lundie. She has spoken to a number of schools in Hawke’s Bay. Emma continues to provide written articles for Flight.
6. Bittern are a species under severe threat from wetland loss, predation, poor food supply and human disturbance. Population trends are negative. The Department of Conservation operate a conservation threat classification system of bittern and last month bittern were upgraded to the highest level of Nationally Critical Threatened Species. Kakapo and takahe  share the same ranking which highlights  the plight of this iconic wetland bird.
7. It is important that DU continue to support  the bittern conservation programme and encourage others (DOC, Forest & Bird) to commit to the preparation of a national bittern recovery plan.
8. In 2015 DU Directors agreed to support the bittern project to the level of $25,000 to enable Emma Williams to continue her research work and purchase transmitters. Expenditure to date is (Emma Williams $7322) and (transmitters $9211.25). The remaining $8467 will be utilised this coming spring/summer.

John Cheyne

Coordinator Project Bittern (Matuku)