Hihi conservation is currently overseen by the New Zealand Department of Conservation www.doc.govt.nz with active management moving more toward independent conservation organizations (see links below) and with an overseeing body (Hihi Recovery Group) with representatives from government, iwi, independent conservation groups and scientists.
Conservation management of the sole remnant population (Hauturu Is.) has been minimal apart from establishing and continuing to trial protocols to monitor the population’s size and demography. Instead, management has focused on establishing additional populations of hihi at other sites by translocation of wild caught hihi from Hauturu and more recently of juveniles and adults from Tiritiri Matangi. To date there have been 20 translocations of wild caught birds to a total of eight sites. In addition, the New Zealand Department of Conservation has maintained a captive breeding facility with small numbers of hihi www.mtbruce.org.nz that are sometimes released into wild populations.
Early attempts to establish hihi on additional islands were done entirely from a species-recovery perspective. Habitat quality was carefully considered, and islands were chosen based on their diversity and abundance of nectar – and fruit-producing species. Based on these considerations, a total of 9 translocations were made to Hen, Cuvier and Kapiti islands from 1980 to 1992. These reintroductions failed to result in self-sustaining populations. Although there was little monitoring on Hen and Cuvier islands, the available information suggested that hihi bred well, at least initially, but nevertheless declined to extinction. More intense monitoring on Kapiti Island led to the hypothesis that an insufficient year-round supply of nectar and food was responsible.
Following this, Hihi were released onto Mokoia Island (1994) and Tiritiri Matangi Island (1995 & 1996) www.tiritirimatangi.org.nz. Tiritiri Matangi already had populations of tui and bellbird (dominant to hihi at food sites), whereas bellbird were absent from Mokoia. Neither island was deemed to have a high probability of maintaining a self-sustaining population of hihi. However, the programs were useful for determining what management was necessary to maintain a viable hihi population and what level of restoration was required to support a self-sustaining population in the long term. Both populations have been intensively monitored. The Mokoia population was predicted to quickly decline to extinction if management (supplementary feeding and nest mite control) were stopped and even with such management there was uncertainty in continued viability. Therefore, all remaining hihi (10) were caught and moved from Mokoia in 2002. In contrast, with continued supplementary feeding and nest management on Tiritiri Matangi, the population is doing well. The hihi translocation to Tiritiri Matangi was part of a restoration plan that included planting a wide variety of nectar – and fruit-producing species in the decade prior to hihi arrival. As these plantings mature we are hopeful that supplementary feeding can be discontinued and allow this population to reach the above mentioned acid test of maintaining self-sustaining populations of hihi, tui and bellbird.
The productivity of hihi on Tiritiri Matangi has been so great that Tiritiri Matangi birds have been the source for translocations to three sites on the main North Island of New Zealand. Transfers to Karori Wildlife Sanctuary (2005), the Ark in the Park project of the Waitakere Ranges (2007 & 2008)www.arkinthepark.org.nz and to Mt Maungatautari (2009 & 2010) Mt Maungatautari mark the first time hihi have been on the mainland of New Zealand since the 1880’s. These sites are managed as mammalian pest-reduced ‘mainland islands’, and differ from the island populations in that dispersal away from these protected areas is possible. These populations are being followed with much interest with the hope that hihi remain within these areas to successfully survive and breed. These most recent translocations were also developed to test how to best combine this style of translocation management with maintaining the genetic integrity of both current and establishing populations. For example, the translocation to Mt Maungatautari in 2009 mixed a majority of birds from Tiritiri Matangi with a smaller number from Hauturu. Keep an eye out on this site for developments!
Text by: John G Ewen & Rose Thorogood