Minding the New Zealand Dotterel's business

Forest and Bird, Volume 20, Issue 3, 1 August 1989, Page 30

Minding the New Zealand Dotterel's business

By

Forest and Bird Bay of Plenty Conservation Officer

Ann Graeme,

long the east coast of the North Island from Northland to the Bay of Plenty are many estuaries, large and small. These estuaries characteristically run out to the ocean through a narrow entrance, protected by a sandspit. To the endemic New Zealand dotterel, these spartan sandspits are prime Real Estate, their most favoured breeding sites. They provide bare sand with all round visibility where the bird’s camouflaged eggs lie in the merest scrape of a nest. The sandspit also offers excellent feeding for the parents and chicks. They can forage for sandhoppers on the ocean beach, or when the weather is rough probe the softer sand on the sheltered estuary side. However, this same real estate is also most favoured by holidaymakers. Many of the best dotterel spits now adjoin sprawling bach communities, and the lonely sand is now trampled by children, dogs and dune buggies. Even more remote sandspits are within range of trailbikes and buggies with their companion dogs. This invasion together with natural mortality has led to an alarming lack of breeding success for the NZ dotterel and for the variable oystercatcher which nests with them. The NZ dotterel population is estimated at fewer than 1,300 birds and oystercatcher numbers about 2,000. Both populations are in decline. What can we do to enhance their survival?

Beginnings

In Waikato Forest and Bird began a project to protect the Wharekawa Wildlife Reserve just north of Whangamata on the Coromandel Coast. An area of sandspit was rope-fenced and signposted, and Waikato Forest and Bird financed a warden to "mind" the birds and record the nestings. In previous years no chicks were reared but after two seasons of protection 15 NZ dotterel and nine variable oystercatchers were fledged. The Department of Conservation now maintains and staffs the Wharekawa Spit, and a similar project at Waikawau Bay. Auckland and northern branches have also supported dotterel protection in Northland, particularly in Mangawhai. This ‘88-89 summer Eastern Bay of Plenty Forest and Bird decided to set up a similar bird minder project at Ohope spit. The branch had scarcely any funds at their disposal, and the project would rely entirely on voluntary efforts. While volunteer "minders" were coordinated by chairman John Lees, the setting

up of the project depended on the enthusiasm and initiative of Ohope members Helen and Adrian Harrison. In November 11 hectares of dune and sand spit were fenced using posts lent by. the Whakatane District Council, 1.8 km of red binder twine provided cheaply by a local firm, ice-cream container plastic fence signs and homemade notice boards. Geoff Moon supplied bird photographs, encased in plastic by a Forest and Bird member to incorporate on the notice boards. The Whakatane Council loaned a wooden hut which was towed to the edge of the fenceline and provided essential shelter from sun, wind and rain. An information handout was prepared and 600 copies donated by the Whakatane Council. Both the council and the Whakatane DoC enthusiastically supported the project and provided staff to help put up the fence. It was a big effort, but the monetary cost of $41 was minimal. Best of all, the project was reported in the national newspapers, and reached the local community through the local newspaper where it was front-page news on three occasions. In December an "Open Day" was held and school parties were told about, and shown the project.

Roster of Minders

A roster of "minders" — Forest and Bird members and locals — "minded" the fence particularly in the holiday season, distributing the information sheets and explaining the project to passers-by. What did the project achieve? Because the fenced area was so large it was difficult to accurately assess how many pairs were breeding — an estimated 10 pairs of NZ dotterels, and eight pairs of variable oystercatchers. In December numerous chicks were seen and nine NZ dotterel chicks counted, but the atrocious weather over Christmas and New Year made sightings difficult and probably increased chick mortality. However, by January many small groups of NZ dotterel and variable oystercatchers were together, presumably parents with "teenage" chicks. Other species also benefited in the protected area. Six pairs of banded dotterels nested within the compound and flocks of more than 4,500 godwits and other migrants roosted undisturbed. Had the fence been erected earlier it would have benefited the white-fronted terns which in September had repeatedly tried to nest but had been driven away by motorbikes.

Probably more important than the achievement of a small number of fledglings has been the education and response of the community. Our volunteer "minders" have no powers to order people to respect the flimsily fenced sanctuary. We relied solely on public goodwill, and scarcely ever met opposition, nor was the sanctuary abused. Although the Ohope Spit has long been a Wildlife Reserve where dogs are forbidden, it used to be a popular place to walk the dog. In the early days of the project our requests not to take dogs along the spit surprised many people and annoyed a few. Now people seem to accept the restriction. Similarly the only occasion when the sanctuary was breached by a dune buggy happened within a day of the fence being erected. Since then no dune buggies, dogs or people have deliberately strayed into the protected area.

Instead hundreds of people have taken our leaflet and peered over the fence to see birds of whose existence most people were previously unaware. Their enthusiasm markedly increased after they had walked around the fence. This public goodwill has to be fostered by communication and this is where newspaper publicity, our information sheet, signposts and personal contact were so important. It is not all plain sailing yet. Many natural and man-made hazards still threaten the breeding birds. Stoats infest the Ohope Spit and must be killing many chicks, so constant trapping is required. Even the best "minded" project cannot always be on duty, and at Wharekawa Spit six dotterel chicks were killed by marauding dogs on a single night. The Wharekawa Reserve

also suffered this summer when cyclone winds drove high seas right across the spit, destroying nests and chicks. Perhaps this past season has been an aberration, but if as predicted it is indicative of the increasing tropical storms which may be associated with the greenhouse effect, the higher wider spits like Ohope may in future better reward our efforts of protection, particularly if the sea level rises.

Black-backed Gull Menace

A particular enemy of NZ dotterel chicks is the black-backed gull. These gulls are multiplying quickly because of their ability to exploit a new and growing food source — municipal rubbish tips. The growing colony of more than 1,000 on Matakana Island flourishes at the Tauranga City Dump. They also pick off local dotterel chicks and besiege white-fronted tern colonies in Tauranga Harbour, killing all the chicks in one season. Fishermen report them attacking little blue penguins, petrels and prions. Many ornithologists regard black-backed gulls as a growing pest species which does not warrant the protection it presently enjoys. Philosophy aside, we felt it prudent to discourage a pair of black-backed gulls that attempted to nest in the Ohope sanctuary. Perhaps the most endearing feature of these projects is the reaction of the birds themselves. At Wharekawa Spit after three years of operation the birds appear to recognise the protection of their fenced sanctuary and are becoming accustomed to people passing by. Although outside the fence parents will try to drive or entice watchers away from their feeding chicks, within the fence they are much less aggressive, and the gangly chicks, particularly the variable oystercatcher, will rest only a few metres from the fence. In contrast the birds at Ohope retreat with alarm and decoy behaviour from passersby. However the minders report after only a few months that the birds are becoming less easily disturbed and are more readily observed from the fence. The survival of an increasing number of species is now at the whim of people. In the case of shore-nesting birds, not just money but public sympathy is needed to protect a lifestyle which is becoming increasingly risky. Our Forest and Bird branches can play a vital role in enlisting public understanding and support for the ornithological tangata whenua of the beaches — the NZ dotterel and the variable oystercatcher.

Project Update — June

In March the fence around the Ohope Spit was dismantled and a new sign has been erected, establishing the area as a bird nesting area until spring. Recently 85 NZ dotterels were recorded in a flock on the Spit, probably the largest flock counted in recent years. It seems plausible that these flocks are important social groups where match-making takes place for the coming breeding season. In the flock was a banded bird from Waikawau some 200 km north.

Flocks of banded dotterels, variable oystercatchers and white-fronted terns are also congregating on the Spit with about 200 overwintering godwits. This coming summer, Te Puke Forest and Bird plan to enlist the support of Maketu residents and set up a community project to protect the birds on the Maketu spit. Ohope and Maketu are the major breeding populations of NZ dotterels and variable oystercatchers in the Bay of Plenty, and their protection will significantly improve the chances for these threatened birds.