The EcoQuest Education Foundation (www.ecoquest.co.nz) operates a centre for field studies in ecology, resource management and environmental policy. In partnership with the Department for Natural Resources, University of New Hampshire, EcoQuest offers semester programmes for university students. As part of the semester, students carry out a research project, which has scientific and/or societal relevance.

EcoQuest students have been involved with the Maungatautari Ecological Island since its inception, and contributed locally to research and field studies. Currently, EcoQuest is conducting baseline ecological monitoring and surveys developed on Maungatautari and Mt Pirongia (a reference site) to be able to assess the response of native species and communities to the future eradication of mammalian pests in the Maungatautari Scenic Reserve. EcoQuest is focusing on birds and invertebrates on Maungatautari and Mt Pirongia, and has also conducted extensive Hochstetter’s frog surveys over Maungatautari in the past two years. These studies have been developed by Dr Matt Baber (EcoQuest Research Director) and Ria Brejaart (EcoQuest Director) in collaboration with MEIT.

Bird Research

Four students (Kathryn Daly, Whitney Schultz, Dhyana Miller, and Laura LaFleur) and Wendy Hare (an EcoQuest field leader and experienced birder), conducted research to investigate native bird communities on Maungatautari and Mt Pirongia (which served as a reference site). The students focused on native avian bioindicators (tui, bellbird, grey warbler, fantails, North Island tomtits, and kereru) as these species are relatively abundant on the two mountains, play an important ecological role, and are known to respond to mammalian pest eradication. As such, this assemblage is considered useful in determining the response of pest eradication on native species.

A total of 50 bird monitoring stations were established on each mountain to ensure a diversity of habitats was represented. At each monitoring station, we recorded the number of individuals of each bioindicator species over a 5 minute period, as well as any species of special concern (e.g., rifleman). Our results suggest that there were both similarities and differences in bioindicator assemblages between the two mountains. Most notably, the relative abundance of tui was significantly higher on Maungatautari, whereas the relative abundance of keruru was significantly lower on Maungatautari compared to Mt Pirongia. This study provides useful pre-eradication baseline data on bird communities on Maungatautari and we will continue this monitoring in the long-term so that we can detect relative population changes of these species in response to the eradication of mammals on Maungatautari.

Mike Stanley and Dan Melnick (two of our students) joined forces with EcoQuest field leader John Longden (an experienced Maungatautari frog searcher). Their aim was to further assess the spatial distribution of Hochstetter’s frogs on Maungatautari, and to estimate the population size. Despite 6 intensive field days their search efforts yielded only 7 frogs, bringing the total number of frogs found in EcoQuest surveys (since May 2005) to 27. The population appears confined to 120 ha area on the south and southeastern side of the mountain. The results of this study indicate that the minimum number of native frogs likely to occur on the mountain is approximately 1000. Estimates were based on such factors as the linear distance of stream habitat in the area where frogs are known to occur, the proportion of suitable stream habitat, and the detection probability (probability of finding individual frogs). The figure of 1000 frogs is considered a minimum because this estimate does not take into account th e probability that frogs will occur in stream habitat classified as non-suitable or in surrounding terrestrial habitat (where they are known to occur). Formal search sites have been established so that we can detect large-scale changes in abundance, and spatial distribution in response to the eradication of mammalian pests. We also conducted brief searches for Hochstetter’s frogs on Mt Pirongia and for Archey’s frogs on Maungatautari but we were unsuccessful on both accounts.

Invertebrate Research

With help from Dr Peter Maddison (EcoQuest Associate and expert entomologist), four students (Jennifer Kulgren, Aaron Webb, Lori Neil, Meghan Spratt, and Tracy Durnell) tackled invertebrate research. This study was a continuation of research on ground dwelling invertebrates with a focus on beetles (Coleoptera). Invertebrates are important in the ecosystem in that they comprise over 95% of non-microbial biodiversity, provide essential ecosystem services, include all trophic groups, and are a major food source for many organisms.

We collected invertebrates over a one month period (Mid October – Mid November 2005) from 120 pitfall traps (72 on Maungatautari and 48 on Mt. Pirongia). We recorded over 1500 beetles from 25 family groups. The most common family groups were Carabidae (ground beetles), Scarabaeidae (dung beetles), Leididae (small carrion beetles), Curculionidae (weevils), and Staphylinidae (rove beetles). Mean Coleoptera richness and total abundance was similar between the two mountains, although species composition differed. On both mountains, richness and abundance tended to be higher in lowland areas and composition also differed. We also found little differences between pitfall traps set inside versus outside the pest-proof enclosure. There are several possible explanations for this: more sampling effort might be needed to detect differences; not enough time has elapsed since the eradication of pests inside the enclosures for significant differences to occur; or invertebrate species that were sensitive to the eradication of mammalian pests have already been extirpated (i.e., only taxa that are able to coexist in the presence of mammalian pests remain on the mountain). This study commenced in November 2004, and has been repeated twice yearly (April and November). We plan to double the current sampling effort duration (to two months periods twice a year) and continue indefinitely so that we can determine long-term changes in invertebrate community structure.