The Ashley

Forest and Bird, Volume 18, Issue 3, 1 August 1987, Unnumbered Page

The Ashley

A Riverbed First

New Zealand's first riverbed reserve could be soon a reality if Canterbury’s Ashley River reserve proposal is agreed to. Much time and effort by Wildlife Officer Ken Hughey and Rangiora High School pupils has paved the way for the historic gazettal and provided an example for other areas in the country. Margaret Baker reports.

N: many school pupils would relish the thought of hours spent slashing broom and lupin — but a few in North Canterbury have approached the task with zeal. Spurred on by Wildlife Officer Ken Hughey’s talk on a proposed reserve for part of the Ashley River, Rangiora High School's seventh form biology students set out to make the riverbed a safer place for birds to nest — and for their efforts were awarded a national Young Conservator of the Year award for 1986. Encouraged by their teacher, Barbara Spurr, the pupils worked on their ‘‘conservation experiment" as part of their environmental education syllabus. Their aims were to clear exotic vegetation, which was reducing the size of the nesting area and encouraging predators, and to monitor public use of the proposed reserve. ‘After listening to Ken’s lecture at a Forest and Bird meeting we decided the only thing to do was to get involved," says Keryn Rickerby, the group leader of the project. "I'd never really been interested in birds before — but now I want to do a wildlife course at Lincoln."’ In March, the 20 pupils spent many hours at the riverbed slashing lupins and broom (and sometimes having enforced lessons on river crossing!) They also spent 10 days monitoring the amount and type of traffic using the reserve area, a 5km section of riverbed stretching west from the Rangiora traffic bridge to the Okuku river confluence. Sense of purpose "It was great doing a project that was relevant to here and now, it gave the whole class a real sense of purpose,’ says Keryn."’ Their report concluded that if the braided riverbed birds, particularly the wrybill, were to continue nesting on the Ashley, the vegetation needed to be cleared continually, vehicles should be banned between September and December (the breeding season), and for overall protection the area should be made a reserve. ‘‘Maybe we have saved the lives of only one bird, maybe a family pair — but therefore we have proved that clearing the vegetation is a good method of assisting the various species during the nesting seasons. ‘‘Even if all we have done is give the proposal a higher profile, we hope our work will help convince local authorities of the need for a reserve,"’ says Keryn. Ken Hughey is just as hopeful. ‘Their project has been a big help, it’s shown that the public are becoming more aware of the special value of the Ashley —

and what's even more important is that a wrybill nested in the area they cleared!’’ Ken first proposed the reserve to the North Canterbury Catchment Board in 1984. If accepted, it will become the first river and its habitat in New Zealand to be protected by such a reserve status. ‘The area is of outstanding value to wildlife, and the reserve would mean protection for birds which are fast becoming endangered species." Of these, the wrybill (endemic to New Zealand), is the most threatened. The five known pairs that nest in the reserve area are the only ones found on the Ashley River. There are only about 5000 of the birds in total. The vulnerable black-fronted tern also breeds in the 5km stretch of the Ashley. ‘The Ashley carries a breeding stock of all the main riverbed bird species,’’ says Ken. ‘The reserve is the most critical nesting area for them."’ Other birds that nest there include the

banded dotterel, pied stilt, South Island pied oyster catcher, black-billed gull (the only colony on the river), and pipit. The Caspian tern, black shag, kingfisher, blackbilled gull, welcome swallow, Australian harrier, paradise shelduck, white-faced heron and spur-winged plover also feed and roost in the area. Ken says many of the birds return to exactly the same spot each year to nest. ‘But now some are being frightened off by the intrusion of vegetation, trail bikes and a changing riverbed due to mechanical works — their range for nesting is shrinking." Small chances of survival He says some birds are so few in number that once one pair is frightened off their chances of survival become very small. As the Rangiora students have shown, the threats to the birds can often be minimised easily and effectively. Clearing vegetation leaves the bare shingle the birds prefer for nesting, and removes

predators such as ferrets, which prey on eggs and chicks. Ken believes clearing would also promote Catchment Board aims of keeping a clear flood-way between river control lines. Gravel extraction is another major threat to the birds. If left uncontrolled, as it was in 1983, it can have a severe impact on them. In that season a black-fronted tern colony and a black-billed gull sub-colony deserted the area because of gravel works disrupting the natural riverbed and nesting areas. By creating shallow pools with gently sloping banks, and clearing vegetation from islands, carefully managed work can enhance the birds’ habitat, says Ken. Restricting extraction to between January and August would also reduce the impact. Conflicts exist with the Rangiora District Council over this matter, as the best shingle mixture is found in the reserve area, and the best time to remove it is spring, for use in summer. An agreement was, however, reached after the Wildlife Service pinpointed wrybill nesting areas and directed the council to areas where shingle could safely be removed. Ken would also like to see recreation ° minimised during the nesting season, especially trail biking. Fishing and shooting have had isolated impacts, although in 1983 shooters were caught killing protected black-billed gulls in the area. Swimming and picnicking don’t usually cause much conflict as they begin at the end of December. ‘Good public relations is needed to make people aware of the special status of the area, and the impact their activities have on the birds,’’ says Ken. ‘‘Nobody needs to miss out on their own fun if we work sensibly together."’ Finally, river and flood control works could interfere with nesting, particularly by reducing the width of the riverbed. Provided these works are kept to existing areas, such as below the traffic bridge, Ken believes they should make little impact. The Catchment Board, which controls the reserve’s land tenure and water resources, is presently dealing with submissions to its draft management plan for the Ashley, and is considering the reserve proposal alongside these. The board's resource planner, John Glennie, says a decision should be made in about six months. ‘‘Personally I don’t think there should be too many problems in accommodating the proposal in some form, whether it’s under the Reserves Act or as a special designation,"’ he says. Ken has proposed that the reserve be given a scientific designation, which would offer considerable scope for wildlife habitat in the area, without compromising Catchment Board aims. ‘‘All I want is for the birds to keep coming back, and as long as I'm alive and kicking I'll keep fighting for the reserve — and I think the board knows that," says Ken.