title: Foraging behaviours of translocated takahē (Porphyrio hochstetteri) at two contrasting sites, New Zealand

authors: Withers, Adara Tehani Savita

subjects: takahē

abstract: The South Island takahē (Porphyrio hochstetteri) is an endangered ground-dwelling species, endemic to New Zealand. To prevent the species’ extinction, individuals were translocated to protected sites, such as off-shore pest-free islands and pest-fenced, mainland sites. The takahē may be one of the most researched bird species in New Zealand, but there are very few studies on its behavioural habits and ecology at these protected offshore island and mainland sites. 

This study was an investigation of translocated takahē foraging behaviour at two very different sites, Motutapu Island (Hauraki Gulf, Auckland) and Maungatautari mainland site (Waikato region), with two translocated takahē populations (18 vs 6 takahē respectively). In total, 24 takahē were observed at the time of this study. The aims of this research were to determine: (1) how takahē foraging behaviour differed between pasture and other habitats on Motutapu Island and at Maungatautari, (2) how other habitat elements (incl. vegetation cover, water, roads, tracks) affected foraging behaviour, and (3) if habitat restoration may assist takahē establishment. This study was conducted in reference to future successional habitat changes on Motutapu Island, as it is subject to active re-vegetation of native trees and shrubs. Similarly, Maungatautari is not actively maintaining the pastoral grassland sites between forest edge and the pest-proof fence. Therefore, without management, natural forest successions of these sites are likely to decrease food availability for takahē in the future. 

Plant species eaten by takahē were identified during field observations. Foraging behaviour was categorised into three main behaviours: (1) cutting for grass-blades, (2) tillering for grass meristems (leaf base, leaf blade discarded) and (3) stripping (grass seeds). A multinomial regression analysis, with confidence intervals of 95% level confidence, determined the odds of a takahē behaviour occurring according to various habitat variables. Foraging behaviours were found to differ according to the percentages of vegetation cover. On Motutapu Island, the main findings were that takahē favoured tillering grass meristems at sites where a high percentage of shrubland was available rather than at sites with high tree cover (vegetation >6 m) or with a high percentage of open grassland. In contrast, stripping seeds was favoured at sites with high tree cover and/or at restoration planting sites. Qualitative behavioural data from Maungatautari showed that takahē foraged primarily on pastoral grassland species, obtained primarily between the fence and the forest.   

Nesting and breeding observations were also made during incubation and chick-rearing. Only one chick reached juvenile-adult stage at Motutapu Island, compared to two chicks at Maungatautari. I identified nest material and nest cover plant species used by takahē (native and exotics- sedges/flax/shrubs/native long grass) during the breeding season and present a plant list based on qualitative fieldwork. Extensive pastoral grasslands on Motutapu Island are now being restored into forested areas, but wetland and native grassland restoration should be another priority for takahē habitat management. Similarly, the Maungatautari Ecological Island Trust (MEIT) may have to control the natural succession of the forest at the edge of the pest-proof fence. Overall, adding native species in pastoral grassland takahē territories at Motutapu Island and Maungautari will be necessary for the future well-being of these translocated takahē. This study has shown that analysing takahē foraging behaviours can help conservation management to improve habitat restoration and subsequent breeding success.

text: Foraging behaviours of translocated takahē (Porphyrio hochstetteri) at two contrasting sites, New Zealand The South Island takahē (Porphyrio hochstetteri) is an endangered ground-dwelling species, endemic to New Zealand. To prevent the species’ extinction, individuals were translocated to protected sites, such as off-shore pest-free islands and pest-fenced, mainland sites. The takahē may be one of the most researched bird species in New Zealand, but there are very few studies on its behavioural habits and ecology at these protected offshore island and mainland sites. 

This study was an investigation of translocated takahē foraging behaviour at two very different sites, Motutapu Island (Hauraki Gulf, Auckland) and Maungatautari mainland site (Waikato region), with two translocated takahē populations (18 vs 6 takahē respectively). In total, 24 takahē were observed at the time of this study. The aims of this research were to determine: (1) how takahē foraging behaviour differed between pasture and other habitats on Motutapu Island and at Maungatautari, (2) how other habitat elements (incl. vegetation cover, water, roads, tracks) affected foraging behaviour, and (3) if habitat restoration may assist takahē establishment. This study was conducted in reference to future successional habitat changes on Motutapu Island, as it is subject to active re-vegetation of native trees and shrubs. Similarly, Maungatautari is not actively maintaining the pastoral grassland sites between forest edge and the pest-proof fence. Therefore, without management, natural forest successions of these sites are likely to decrease food availability for takahē in the future. 

Plant species eaten by takahē were identified during field observations. Foraging behaviour was categorised into three main behaviours: (1) cutting for grass-blades, (2) tillering for grass meristems (leaf base, leaf blade discarded) and (3) stripping (grass seeds). A multinomial regression analysis, with confidence intervals of 95% level confidence, determined the odds of a takahē behaviour occurring according to various habitat variables. Foraging behaviours were found to differ according to the percentages of vegetation cover. On Motutapu Island, the main findings were that takahē favoured tillering grass meristems at sites where a high percentage of shrubland was available rather than at sites with high tree cover (vegetation >6 m) or with a high percentage of open grassland. In contrast, stripping seeds was favoured at sites with high tree cover and/or at restoration planting sites. Qualitative behavioural data from Maungatautari showed that takahē foraged primarily on pastoral grassland species, obtained primarily between the fence and the forest.   

Nesting and breeding observations were also made during incubation and chick-rearing. Only one chick reached juvenile-adult stage at Motutapu Island, compared to two chicks at Maungatautari. I identified nest material and nest cover plant species used by takahē (native and exotics- sedges/flax/shrubs/native long grass) during the breeding season and present a plant list based on qualitative fieldwork. Extensive pastoral grasslands on Motutapu Island are now being restored into forested areas, but wetland and native grassland restoration should be another priority for takahē habitat management. Similarly, the Maungatautari Ecological Island Trust (MEIT) may have to control the natural succession of the forest at the edge of the pest-proof fence. Overall, adding native species in pastoral grassland takahē territories at Motutapu Island and Maungautari will be necessary for the future well-being of these translocated takahē. This study has shown that analysing takahē foraging behaviours can help conservation management to improve habitat restoration and subsequent breeding success.

year: 2014

title: Ecology of vascular epiphytes in urban forests with special reference to the shrub epiphyte Griselinia lucida

authors: Bryan, Catherine Louise

subjects: Epiphyte

abstract: This research investigated the ecology of vascular epiphytes and vines in the Waikato region of the North Island, and the water relations of the shrub hemiepiphyte Griselinia lucida. The main goal was to develop robust recommendations for the inclusion of epiphytic species in urban forest restoration projects. To achieve this, three broad questions were addressed: 1. How are vascular epiphytes and vines distributed throughout the nonurban and urban areas of the Waikato region, and how does this compare to other North Island areas? 2. Why are some epiphyte and vine species absent from urban Hamilton and what opportunities exist for their inclusion in restoration projects? 3. How does Griselinia lucida respond to desiccation stress and how does this compare to its congener G. littoralis? To investigate questions one and two, an ecological survey of the epiphyte communities on host trees in Waikato (n=649) and Taranaki (n=101) was conducted, alongside canopy microclimate monitoring in five Waikato sites. Results show that epiphyte and vine populations in Hamilton City forests represent only 55.2 % of the total Waikato species pool, and have a very low average of 0.8 epiphyte species per host. In contrast, the urban forests of Taranaki support 87.9 % of the local species pool and have an average of 5.5 species per host tree. The low diversity and abundance in urban Waikato can be primarily attributed to the alteration of canopy microclimates by edge effects. Mean temperature and vapour pressure deficits in Waikato were 1.9 °C and 1.1 kPa (respectively) higher in the canopy of small urban patches than the larger, nonurban forests. These warmer and drier conditions are speculated to be interrupting species accumulation and community formation processes. This phenomenom is not as pronounced in Taranaki which has larger trees and higher rainfall. Epiphyte diversity and abundance was also found to be associated with seed dispersal distances and the size, bark type, and architecture of host trees. To link the microclimate findings with physiological limitations of epiphytes and to address question three, a desiccation tolerance experiment was conducted on the shrub hemiepiphyte Griselinia lucida. Moderate and severe levels of desiccation stress were applied to seedlings of G. lucida and its terrestrial congener, G. littoralis. Both species endured over two months of drought with negligible mortality. In G. lucida, stomatal conductance reduced to zero, and leaf bulk elastic modulus reduced from 8.09 (±0.51) MPa in the control group to 3.66 (±0.61) MPa under severe stress. When compared to G. littoralis, G. lucida exhibited a more acute response to stress and recovered faster with rewatering. However, the overall response of each species was similar and both species can be classified as desiccation postponers. To summarise and combine the findings of this research with existing information on Griselinia lucida, a contribution to the New Zealand Biological Flora Series for this species is presented. Recommendations for the inclusion of epiphytes in restoration projects are presented. Reintroductions should use epiphyte and vine species that are appropriate for the conditions of the target forest, and focus on large host trees in relatively humid microclimates.

text: Ecology of vascular epiphytes in urban forests with special reference to the shrub epiphyte Griselinia lucida This research investigated the ecology of vascular epiphytes and vines in the Waikato region of the North Island, and the water relations of the shrub hemiepiphyte Griselinia lucida. The main goal was to develop robust recommendations for the inclusion of epiphytic species in urban forest restoration projects. To achieve this, three broad questions were addressed: 1. How are vascular epiphytes and vines distributed throughout the nonurban and urban areas of the Waikato region, and how does this compare to other North Island areas? 2. Why are some epiphyte and vine species absent from urban Hamilton and what opportunities exist for their inclusion in restoration projects? 3. How does Griselinia lucida respond to desiccation stress and how does this compare to its congener G. littoralis? To investigate questions one and two, an ecological survey of the epiphyte communities on host trees in Waikato (n=649) and Taranaki (n=101) was conducted, alongside canopy microclimate monitoring in five Waikato sites. Results show that epiphyte and vine populations in Hamilton City forests represent only 55.2 % of the total Waikato species pool, and have a very low average of 0.8 epiphyte species per host. In contrast, the urban forests of Taranaki support 87.9 % of the local species pool and have an average of 5.5 species per host tree. The low diversity and abundance in urban Waikato can be primarily attributed to the alteration of canopy microclimates by edge effects. Mean temperature and vapour pressure deficits in Waikato were 1.9 °C and 1.1 kPa (respectively) higher in the canopy of small urban patches than the larger, nonurban forests. These warmer and drier conditions are speculated to be interrupting species accumulation and community formation processes. This phenomenom is not as pronounced in Taranaki which has larger trees and higher rainfall. Epiphyte diversity and abundance was also found to be associated with seed dispersal distances and the size, bark type, and architecture of host trees. To link the microclimate findings with physiological limitations of epiphytes and to address question three, a desiccation tolerance experiment was conducted on the shrub hemiepiphyte Griselinia lucida. Moderate and severe levels of desiccation stress were applied to seedlings of G. lucida and its terrestrial congener, G. littoralis. Both species endured over two months of drought with negligible mortality. In G. lucida, stomatal conductance reduced to zero, and leaf bulk elastic modulus reduced from 8.09 (±0.51) MPa in the control group to 3.66 (±0.61) MPa under severe stress. When compared to G. littoralis, G. lucida exhibited a more acute response to stress and recovered faster with rewatering. However, the overall response of each species was similar and both species can be classified as desiccation postponers. To summarise and combine the findings of this research with existing information on Griselinia lucida, a contribution to the New Zealand Biological Flora Series for this species is presented. Recommendations for the inclusion of epiphytes in restoration projects are presented. Reintroductions should use epiphyte and vine species that are appropriate for the conditions of the target forest, and focus on large host trees in relatively humid microclimates.

year: 2011

title: Legal responses to mental health: Is therapeutic jurisprudence the answer – the experience in New Zealand

authors: Toki, Valmaine

abstract: The orthodox understanding of ‘ethics’ encompasses a system of moral principles that define good and bad behavior. When applied to mental health, various jurisdictions, including New Zealand, have codified these principles together with the obligations on health service providers to meet these codified principles and standards. Underpinning this relationship is one of mutual trust where the physician has a responsibility, for example, to secure informed consent prior to any treatment. The existence of this therapeutic relationship can be applied when an offender who presents with a mental illness is subject to the criminal justice system.

text: Legal responses to mental health: Is therapeutic jurisprudence the answer – the experience in New Zealand The orthodox understanding of ‘ethics’ encompasses a system of moral principles that define good and bad behavior. When applied to mental health, various jurisdictions, including New Zealand, have codified these principles together with the obligations on health service providers to meet these codified principles and standards. Underpinning this relationship is one of mutual trust where the physician has a responsibility, for example, to secure informed consent prior to any treatment. The existence of this therapeutic relationship can be applied when an offender who presents with a mental illness is subject to the criminal justice system.

year: 2017