Ranger, Catherine Stewart, reports on the tawaki season at Gorge River…
The aim of the monitoring: Tawaki nests were monitored for survival/failure due to predation and to assess general chick growth and apparent health as an indication of food supply and marine conditions.
Method: 27 nests were checked 6 times between 20/8/2024 and 28/10/2024 at intervals of 10 to 18 days. 9 of these nests were also monitored with Little Acorn trail cameras.
An additional 15 nests known from previous years were checked on 20/8/2024.
2 lured cameras were baited with cooked meat in a fine metal mesh ball inside a tin can wired to a tree approx. 1m above the ground, early and late in the season.
Results for the season
Results throughout the season were limited due to camera and battery failure. The cameras have reached the end of their life and we have been fortunate to secure a grant for new cameras in time for the 2025 season. There was some difficulty getting batteries recharged (relying on solar power in this remote location) in the time between nest visits.
Nest checks
All birds were sitting on eggs by 20 August.
Of the additional 15 old nests, none showed any sign of having been used.
There was no sign of hatching on 28 August. All eggs were hatched by September 22nd. Chicks appeared well fed throughout the season and appeared to grow at an average rate. Just two chicks were seen during the nest checks at the end of October, suggesting two successful nests in addition to those with cameras present.
24 of 27 nests with sitting birds on 20 August had at least one egg present.
Nest cameras
Of the nine camera-monitored nests, two had healthy chicks to the middle of October and four to the end of October/early November.
One (late) nest had two healthy chicks present close to the end of the guard phase on 10 October. Due to camera failure, there was no further sight of them in the next 18 days and the nest appeared empty and abandoned after 28 October.
Two nests appeared to have failed by mid-September, one after a stoat visit.
Lured Cameras
Results in September and early October were haphazard with camera and battery failure.
Two new Bushnell Trail cameras donated to the Trust were deployed on 27 October. Several possums and rats were seen near the bait. Four stoats were seen early in December.
Conclusions
It was average season, i.e. not seeing two chicks but with most nests raising one chick. There were low numbers of stoats and there also appeared to be plenty of food around, looking at the chicks, and that was confirmed by The Tawaki Trust.
Heading into year 12 now, the aim will be to maintain continuity of data with the added benefit of new cameras.
Catherine Stewart, West Coast Penguin Trust, Autumn 2024
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!
