Chair Report 2019
Welcome everyone to this AGM. The Ashley-Rakahuri Rivercare Group was formed in 1999 and became an Incorporated Society in 2005. This report is largely an adaptation of the summary from our 15th annual report for the 2018-19 season, which is just about completed.
Activities were focussed on management to assist the feeding and breeding of the threatened species in the river, particularly the wrybill (ngutupare), black-billed gull (tarapuka) and black-fronted tern (tarapirohe). To this end, the main actions undertaken involve habitat management (mainly weed control), monitoring bird populations and breeding success, predator control, restricting 4WD access to the river during the breeding season, and improving awareness by the public and river management decision-makers.
The Group’s finances are in good shape. We are now mostly self-funded, with finances coming from a trap making and selling project, donations and a sponsorship via Karikaas Natural Dairy Products Ltd – plus grants for larger specialist projects (such as weed clearing and video making) from DOC, ECan and its Waimakariri Zone Committee, and the Rata Foundation.
Habitat enhancement. The impact of weeds has changed considerably over recent years. After their increase between 2014 and early 2017 causing a major loss of clear gravel areas (essential for bird breeding), large floods over the 2017 winter increased clean shingle areas from around 30ha to over 250ha. However, these clear areas are now being reinvaded. So past weed clearing efforts have been continued, with a bulldozer used to rip and blade 10ha in July 2018, but weed regrowth over the subsequent summer was significant. Over this past winter, a trial using a tractor-mounted ripper was initiated, with early results indicating that this may lead to a more cost-effective and environmentally friendly means of maintaining weed control in the future.
Bird surveys. Although the bird population trend up to 2014 was a positive rising one, it reversed (declined) in the following 2 years – most likely associated with increased weed invasions. However, the survey figures for November 2017 and 2018 indicate that this decline in bird populations has stopped. Wrybill survey numbers (20) were the second-highest ever. Black-fronted terns and S. Is pied oystercatchers were also more frequent than usual, but numbers of banded dotterels and pied stilts were down on last season and the long-term average. Black-billed gull survey numbers were low but did not include a large colony of over 2000 birds which arrived after the survey date.
Monitoring of breeding birds. At least eight pairs of wrybill took up territories in the study area in 2018-19 – the same number as in the previous two seasons. A minimum of 6 chicks were fledged by six pairs, for a productivity of 0.75 chicks fledged per pair. Such productivity is above the previous season (0.63) and close to the long-term average of 0.79. Black-fronted tern breeding attempts remain fickle, with many nests abandoned, often for unknown reasons. As in the previous year, 70-80 pairs built nests, but productivity was only 0.25, well below the long-term average of 0.41. For the second time in 5 years, a black-billed gull colony returned to the riverbed. The first attempt by over 2000 birds below the SH1 bridge was flooded out, but the colony re-established at the Smarts site. This colony was closely monitored, mainly by aerial bird counts using a drone. Approximately 700 nests resulted in 450-500 chicks fledging, for a productivity of between 0.64 – 0.71. This is well above the long-term riverbed average of 0.32. Breeding productivity of other species was not recorded, but signs of success were noted at many sites.
Predator control. The number of trap-nights during the 2018/19 summer breeding season was 33,742 – the highest since regular trapping started in 2004, and 36% more than in the previous season. The overall summer catch rate was 0.41 per 100 trap nights, close to the previous season’s rate of 0.44, and well below the long-term average of 0.86. The main reason for this decline over the long period is due to fewer hedgehogs being caught. The outstanding feature of the summer period was the large increase in rat catch – 43 compared with 9 in the previous period. Weasel catch also was considerably larger – the reasons for both increases are unknown. The overall winter catch rate was 0.73 per 100 trap nights – the highest recorded since winter trapping began in 2014. It is mainly due to the large increase in rats and weasels caught. Moves are underway to increase trap numbers to cover the entire 21km riverbed margin on both banks, raising the total number of traps from the current 242 to close to 500. Rats will be specifically targeted by the deployment of poison bait tunnels, and colonies of breeding birds will be protected by a surrounding grid network of traps. Over the past year, the Waikuku Estuary Trapping Group has been managing over 100 traps around the estuary. The trap catch rate was 0.63 – close to the riverbed average of 0.59. As in the riverbed, the most notable feature was the high numbers of rats and weasels caught.
Meetings / members and awareness / education. The group has 45 members and 103 recipients of regular update emails. During the 2018/19 season, the Group held four meetings, with attendance numbering between 15-18. The Group also has an 8-person Management Committee for decision-making and funding approval of small tasks requiring immediate attention. Over the past year, many opportunities have been taken to ensure that the public were kept aware of the Group’s activities. Fifteen articles appeared in local papers. Powerpoint presentations were given to six schools, plus presentations were given to the Waimakariri Zone Committee, local scouts and four service clubs. An interview was given to the local radio ‘Compass FM’ and from October through to February the Rangiora cinema showed a ‘screen vista’ about the Group prior to every film showing. A regular email update was sent out during the breeding season. The Group’s 20-minute documentary/ video ‘Rakahuri Rescue’ was launched in the Rangiora Town Hall on March 21. It has been well received throughout the country, with some seeing it as a ‘benchmark’ record of a successful community group in action. A definite highlight of the past year, was the Group’s winning of the Australasian Wildlife Management Society’s ‘’Practical Management Award’ for 2018. We were invited to accept this award and present a talk at the annual conference of the Society, held in Hobart during December. Other highlight talks were given at the launch of the ‘Year of the Wrybill’ event at Miranda, south Auckland (March 10), and the BRaid-organised braided river seminar on June 26. Karikaas Natural Dairy Products Ltd in Loburn now uses our name, plus images of riverbed birds, on their premier cheese packages, in return for which we get a percentage of profits. Our website was upgraded and managed by Sonny Whitelaw, while Steve Attwood ran our Facebook page (https://www.facebook.com/ashleyrivercare). Relative to the latter, Steve records ‘a record performance across the board’. Both social media outlets are vital as they serve as our ‘shop window’. The Group remained closely associated with staff from DOC, the Waimakariri District Council and local Zone Committee, Environment Canterbury (ECan) and the Ashley-Rakahuri Regional Park – plus contributed actively to the running of BRaid Inc, a group which aims to improve the ecological welfare of all braided rivers in Canterbury.
Conclusion. Relative to the future success of rare and endangered shorebird species breeding in the Ashley-Rakahuri river, bird populations and breeding success increased significantly from 2000 – 2014, but then declined through the subsequent 2 years – due primarily to a major increase in weed-infested areas. Over the past 2 years, much effort has gone into artificial weed removal and increasing predator trapping. It appears that the bird population decline has been arrested. The major challenges now involve maintaining adequate weed control, further improving predator control (particularly relative to climbing numbers of rats and weasels), and maintaining the interest and involvement of the local community and major decision-makers in bird management on the Ashley-Rakahuri River.
Last but never least, my heartfelt thanks go to all members of the Group for the work they have put in over the past year. I don’t like picking out individuals, but there are some I must mention: Joan Miles for her work as Secretary, Sue Mardon for her excellent work as Treasurer, Peter Whitehead for his organisation of the trapping teams, Geoff Swailes for all our trap making, and Grant Davey for his mapping and record-keeping skills. Steve Attwood also deserves special mention for his willing help and success in the promotion area. Ongoing thanks are always due to the likes of ECan and their Regional Park staff, the Waimak DC and DOC. We might be the body which makes passionate pleas on behalf of the public, but without their professional support, it would be very hard to make meaningful progress.
Nick Ledgard
ARRG Chair
August, 2019
