This started in March 2017 as a possum trapping project in order to maintain and enhance the mistletoe in the Lake Ōhau beech forests and remnants. The beech forests around Lake Ōhau contain nationally and internationally significant mistletoe populations of scarlet mistletoe (Peraxilla colensoi), red mistletoe (Peraxilla tetrapetala) and yellow mistletoe (Alepis flavida).
All three of these species are ranked as ‘Declining’ according to the Conservation Status of New Zealand’s Indigenous Vascular Plants (de Lange et al 2012).
The Lake Ōhau area is recognised by DOC as one of the highest ranked South Island priority areas for mistletoe conservation.
Stage 1 of the project focuses possum trapping effort on the public conservation land between Parsons Creek and Freehold Creek on the western shore of Lake Ōhau.
Stage 2 of the project started in May 2023 with the installation of traps to catch mustelids (stoats, weasels and ferrets), rats, hedgehogs, cats and mice. The focus on these animal pest species is to ensure the birds and insects that pollinate the mistletoe are protected from predation.
Project Status: Possum Trapping Permit approved by DOC on 9 March 2017. Trapping permit for animal pest species listed above approved by DOC in April and August 2023.
Current activity: Installation of 80 “Trapinator” possum traps in April 2017 and more traps added in early 2020 and in 2022 -104 trapinator traps.
26 DOC150 and 26 DOC250 traps installed in May/June/July 2023 – each with a mouse trap.
Reporting: Numbers of possums caught per month (Table 1) and results of two-yearly monitoring of identified mistletoe plants. Number of other animal pest species caught per month (Table 2).
Table 1: number of possums caught per month
| Month | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
| January | – | 8 | 2 | 3 | 6 | 6 | 3 | |
| February | – | 1 | 8 | 5 | 7 | 6 | 4 | |
| March | – | 21 | 8* | 4 | 16 | 3 | 3 | |
| April | 12 | – | 6 | # | 0 | 5 | 1 | 1 |
| May | 22 | – | 6 | # | 5 | 3 | 3 | 12 |
| June | 11 | – | 5 | 9# | 9 | 1 | 4 | 1 |
| July | 12 | – | 3 | 3 | 8 | 2 | 2 | 3 |
| August | 6 | – | 5 | 9 | 7~ | 7 | 8 | 7 |
| September | 2 | – | 3 | 5 | 7 | 1 | 4 | 2 |
| October | – | – | 3 | ^ | 2 | 0 | 4 | 4 |
| November | – | 7 | 3 | 1 | 3 | 3 | – | 2 |
| December | – | 12 | 4 | 3 | 4 | 3 | 10 | |
| Total | 65 | 19 | 68 | 48 | 57 | 54 | 51 | 42 |
– trapping suspended September 2017 to October 2018 because of TB Free poisoning operation in trapping area.
* traps checked to 10 March 2020
# traps not checked in late March, April, May and June with covid-19 restrictions, 9 possums found when traps checked at end of June 2020.
^ traps not checked in October, after 4 October 2020 wildfire
~ traps not checked from 18 August due to covid-19 restrictions
Table 2: number of other animal pest species caught per month
| Month | 2024 | |||||||
| mouse | rat | unspecified* | ferret | stoat | weasel | hedgehog | feral cat | |
| January | 10 | 4 | 2 | 1 | 10 | |||
| February | 25 | 14 | 2 | 3 | ||||
| March | 28 | 6 | 3 | 9 | 4 | |||
| April | 49 | 3 | 4 | 1 | 7 | 3 | ||
| May | 12 | 1 | 1 | 3 | 2 | |||
| June | 43 | 2 | 1 | |||||
| July | 23 | 1 | 3 | 1 | 1 | |||
| August | 20 | 1 | 1 | |||||
| September | 4 | 1 | 1 | |||||
| October | 11 | 1 | 1 | 4 | ||||
| November | 6 | 1 | 1 | 1 | ||||
| December | ||||||||
| Totals | 231 | 4 | 24 | 18 | 6 | 2 | 40 | 9 |
| Month | 2023 | |||||||
| mouse | rat | unspecified* | ferret | stoat | weasel | hedgehog | feral cat | |
| January | ||||||||
| February | ||||||||
| March | ||||||||
| April | ||||||||
| May | 1 | 5 | 1 | 1 | ||||
| June | 8 | |||||||
| July | 20 | 4 | 1 | |||||
| August | 37 | 13 | 1 | 1 | 1 | |||
| September | 26 | 2 | 9 | 1 | 1 | 4 | ||
| October | 26 | 1 | 4 | 1 | 8 | |||
| November | 21 | 1 | 11 | 4 | ||||
| December | 35 | 4 | 27 | 1 | 1 | 25 | 1 | |
| Totals | 173 | 9 | 68 | 8 | 2 | 4 | 42 | 2 |
