The Trust’s local tawaki rangers monitored nests at three sites in South Westland during the 2020 tawaki breeding season, Knight’s Point, Jackson Head West and Gorge River, to establish breeding success. Monitoring discontinued when chicks left the nest to creche. Crèche areas were checked for signs of predation. Many of these nests also had trail cameras set up to observe breeding success and predator activity and the final sets of images are being analysed through the Jobs 4 Nature programme. More details to follow once all the data is in.
The additional effort to monitor predators during the 2020 breeding season was because it followed a beech mast (massive seedfall event) and it was expected we would see many early chick deaths due to stoat predation, as was observed in the 2016 season. This did not eventuate. It is difficult to measure subtleties of the beech mast (timing and local severity), and the subsequent increases in mouse, rat and stoat populations. Despite this year’s findings, the dynamic forest change led by a beech mast is still present as a threat to all forest dwellers, including tawaki chicks. We hope to learn more once the imagery from the three colonies has been fully analysed and reviewed.
Summary of breeding success, noting that, unless food is unusually abundant or very scarce, and assuming no predation, one chick is usually raised per nest.
| Site | Nests monitored | Chicks seen at nest – pre crèching | Breeding success to crèching | Predator / disturbers filmed | Predation events at nest | Predation at creche seen |
| Knight’s Point | 14 | 14 | 1 | Possum; rat | 0 | 0 |
| Jackson Head West | 25 | 22 | 0.88 | Possum; rat; deer; stoat | 0 | 0 |
| Gorge River | 24 | 20 | 0.83 | Possum; rat; deer | 0 | 0 |
While materials were chosen that would stand up to the harsh coastal conditions, those same coastal conditions are conducive to plant growth! Occasional checks of the fences have been carried out by volunteers and rangers so that any maintenance needs can be identified and remedied. The never-ending need for maintenance is managing the vegetation that can grow through the fence, for example gorse, blackberry and hydrangea, pushing it to breaking point in places, or flop over causing damage from the weight of rank grass, rushes and weeds such as montbretia.
Volunteers recently spent a few hours tidying up the main fence along Woodpecker Bay north of Punakaiki so a big shout out to them - thank you Fiona, Jony, Reef, Katrina, Mandy, Marty, Teresa and Deb! Flax had been pressing down on the fence, but now the fence has been freed up by these wonderful volunteers - and they picked up a fair bit of rubbish too.
Volunteer Natassja Savidge has offered to check and help maintain the Hokitika penguin protection fence and joined Ranger Lucy Waller and Manager Inger Perkins in May to inspect the length of the fence. Some minor issues were found but the main finding was the extent of the vegetation growth that was damaging the fence in places. Big thanks to Natassja!
