In an opinion piece earlier this month, Wanganui tramper and conservationist David Scoullar took a gloomy view of the future for bird populations in Whanganui National Park and surrounding areas. Jim Campbell, acting area manager for the Department of Conservation Whanganui Area, responds.
Dave Scoullar, in his Conservation Comment, comments on the scale of the challenge to protect and restore bird populations in Whanganui National Park and surrounding areas. While grateful to Dave for highlighting this challenge, I'd like to update readers on some of the successes.
Dave identifies the vision set for the park in the management plan and contrasts that vision with the status of various threatened species as at 2005, but a lot has happened since then. Dave notes the Kia Wharite project that partners DoC, Horizons Regional Council, iwi and landowners are implementing over about 180,000ha as the one bright spot. It's easily the largest biodiversity restoration project in New Zealand and, as one of its outcomes, is helping give effect to the vision summarised in the management plan.
Within the park about 60,000ha of the total 74,000ha are included in the Kia Wharite project and predatory pests (possums, rats and stoats) in these areas are controlled with tri-annual applications of 1080-laced baits. About half of this area is also subject to intensive goat control. Elsewhere in the Kia Wharite project area a mix of pest control activities includes possum control, goat control, predator trapping and fencing funded to varying degrees by the partners and other key supporters, such as Genesis Energy.
The two key indicator species, kiwi and whio, show positive trends. A massive amount of data from kiwi call count recorders is being analysed but call rates of more than 6 per hour from some sites is not uncommon and, over three years, kiwi were heard from all 72 sites where automatic recorders were deployed. For whio on the Manganui-o-te-Ao, which is the site with the longest history of monitoring and predator trapping, the number of pairs of ducks has steadily increased over the past decade, and similar success is being achieved on adjacent rivers through the hard work of many individuals and organisations. Within the park we have observed increasing numbers of whio on rivers such as the Mangapurua and others subject to the 1080 treatments. We hope that, over time, whio will repopulate all of the suitable waters within the 60,000ha treatment area.
Equally exciting in the national park is the frequency of reports we receive from staff and others of the recovery of forest bird populations within our predator control area. Flocks of kereru and whitehead, a commonness of tui and bellbird, an ubiquity of robins, tomtit and rifleman and relatively frequent reports of long-tailed cuckoo, falcon and kaka are all pointers to an optimistic future for these populations in this area.
Of course, there is much more to do, and we continue to look for resources that might enable us or others to achieve similar success in the rest of the park and adjoining areas such as the Waitotara Conservation Area. In the meantime, we hope Dave gets a chance, on his next trip into the park, to appreciate the birdlife. Believe it or not, we've had complaints that the dawn chorus stops people getting a decent sleep-in while they're in the park!