Saddleback transfer Motukawanui Island

Forest and Bird, Volume 16, Issue 4, 1 November 1985, Page 17

Saddleback transfer Motukawanui Island

by Bay of Islands

Maritime Park staff

I n February 1983 a Wildlife Service and Bay of Island Maritime and Historic Park team released 16 rare North Island saddleback on Motukawanui Island in the Cavalli Islands. The question on everyone’s minds was: would the birds adapt and survive in their new environment, or would they succumb to undetected predators? The answer to that question is not yet at hand, although recent results are not encouraging as early ones. The coming

breeding season will be critical to the hopes of everyone who has taken an interest in the release programme. Once widespread in the North and South Islands, the saddleback declined rapidly towards the end of the last century, surviving only on Hen (Taranga) Island and a few islands off Stewart Island. By 1962, Taranga supported the last remaining population of North Island saddleback; the species was staring possible extinction in the face. In response,

the Wildlife Service started a research programme, then gradually transferred the birds onto nine other islands over a number of years. Valuable national asset Meantime, Wildlife and agencies such as the Bay of Islands Maritime and Historic Park have continued to survey islands for rodents and mustelids. It was therefore with some excitement that our park staff confirmed Motukawanui might be free of rodents, except for the relatively innocuous kiore. Newly-discovered predator-free islands are as rare as the endangered species liberated on them. Motukawanui had emerged as a valuable national asset. The Wildlife Service proposed a trial release of saddleback on Motukawanui for February 1983. The team which went to Taranga included Wildlife Service and park staff, as well as members of the public. Excitement of the hunt Mist-netting saddleback amongst the rugged, volcanic features of Taranga is quite an art. It has all the excitement and pumping adrenalin of the hunt, with none of the recriminations of carnage. Some participants, however, are known to suffer from smug satisfaction. Sixteen birds were caught and released, four fewer than the target level. To those involved, this represented the first tangible reward, and the remainder of 1983 was tense and full of speculation.

Then, in February 1984, a routine monitoring team was jubilant to find conclusive proof of breeding. As a consequence, a second release of 30 birds was quickly planned and put into action by the Wildlife Service. Bad luck dogged the second capture programme: first rough seas delayed the start, and then rain set in. Two weeks later a disappointed team left the island with a saddleback catch which barely made double figures. A redeeming feature of an uncomfortable but memorable trip were the seven female birds caught. These would help the initial imbalance of sexes resulting from the first transfer.

Today, at the beginning of the 1985 breeding season, the number of saddleback on Motukawanui are estimated at 20. As yet the reasons for the low population are not apparent, especially since the birds have established well on Tiritiri Matangi in the Hauraki Gulf, an island similar in many respects to Motukawanui. It is managed by the Hauraki Gulf Maritime Park. The co-operation and goodwill of all those involved in the project has been its single most impressive feature. Were it not for the two Government departments, numerous individuals and private organisations assisting the park, saddleback would not be on Motukawanuli.