Low Hihi numbers at Ark in the Park are disappointing, but in spite of that many lessons for the survival of the species have already been learned.

Our ongoing monitoring efforts have unfortunately detected only very low numbers of hihi in the Ark area this summer with 5 males present. One female (from the 2008 release) who reproduced successfully last year was also observed initially. – but then  has not been seen anymore  lately.  Such fall in the numbers compared to last year  when there were 19 adults, 13 nests and more than 25 fledglings , is extremely  disappointing, but similar events have happened at other sites where hihi re-introductions been started in the past.  With reintroductions in general (various species) it is not unusual that several attempts are required before an ongoing  population establishes itself.   The reintroduction of hihi to the Ark in the Park was always known to have an experimental element to it – the Ark is the only site with hihi where a predator controlled site is surrounded by good hihi habitat  that is not predator controlled and that may act as a sink to “lure” hihi away. This is very different from hihi on offshore islands or even hihi in areas of good bush surrounded by farmland of suburbs;    As such the Ark is a testing site for the overall national efforts under the guidance of the hihi recovery group, and the reintroduction efforts into the Ark, even when they are disappointing to us such as the ones this year, allow everyone  to learn  valuable lessons for the overall long term survival of hihi in New Zealand.

There will not be a top-up translocation to the Ark at the end of summer this season, because with limited numbers of hihi available each year, the national priorities of the hihi recovery group were to make those available to Maungatautiri and Kapiti instead.  We are hopeful that the individual male hihi which have been surviving very well so far (two are from the 2007 release for instance), will still be around next year, when a new translocation attempt to the Ark is hoped for.  For this reason, we want to continue to provide them with sugar water in the existing feeders as it is a likely a factor in continued attracting of some of those individuals to the territories they have. 

The low numbers this season, in spite of a successful breeding season last year  are probably due to a combination of:
•	Female exhaustion (one female last year e.g.  had one failed nesting attempt and then 3 successful attempts resulting in at least 11 fledglings, after which she was observed in a much “worn out” state.  
•	High feral cat numbers in the Ark  at the end of last season (Robin were also  badly affected last year). Especially fledgling and juvenile hihi may have been impacted.  This issue  has  been addressed in the present season by being able to deploy kill traps as well as life traps.
•	Unusually cold October 2009 temperatures
•	Dispersal away from  the Ark area with predator control 
•	Stochasticity associated with low numbers (this simply means that with small numbers, random events may also cause the numbers to go down drastically without  a particular ecological “cause” – simply through statistical flukes).

Things that we have already  learned from the Ark re-introduction include:
•	Hard release (where birds are not kept in an aviary first) provide a better chance of long term survival than soft releases.
•	Of the 5 males observed this season 2 are from the February 2007 release (hence in their 3d  simmer season in the Ark), 2 from the 2008 release (in their summer breeding season), and one unbanded, presumed fledged last year.   This confirms that  hihi can survive several years in the Ark habitat.
•	We also know of at least a few hihi that are likely around outside the Ark. At least one pair of hihi can be considered as confirmed to the SW and observations also suggest hihi presence in a few other areas outside the Ark.    Moreover, one of the males from 2008 release  who had a successful breeding season last year and has been observed again this season alternates between Ark and a site on Kitewaho road (2.5 km) away and outside the Ark -  and has done so successfully for almost two years. This confirms  that individuals can survive outside the pest controlled area and that  individuals that disperse outside the core area can also come back, and hence should not always be considered “lost” to the population
•	Hihi at Ark in the Park all used natural nest cavities in kauri, which hadn’t been recorded ever before. They were also recorded  using a wider range of natural foods, including from plant species not previously recorded for hihi. 
•	Hole breeding introduced species such as rosella or mynah can cause disturbance to nesting hihi, and they need to be managed at least near the nest sites.
•	This is consistent with the prediction  that if a population can be established, it is likely to be eventually self sufficient - not requiring ongoing management with nest boxes or artificial food and  trying to get the  establishment of a new population through repeated translocation attempts   hence remains a worthwhile effort for the long term survival of hihi as a species.