title: The application of elemental fingerprinting techniques to identify population connectivity using austrovenus stutchburyi recruits

authors: Niemand, Clarisse

subjects: elemental fingerprinting

abstract: The density, distribution and dynamics of benthic bivalve populations are believed to be largely determined by the planktonic larval phase of the life history. As the hard parts of larvae, such as the prodissoconch (larval shell), develop and grow, ambient environmental conditions are recorded as chemical signatures (elemental fingerprints). If the chemical signals of reference sites are known, the larval signatures can be matched to reference sites, hereby reconstructing the origin of the larvae. The collection and identification of larval bivalves is extremely difficult, however, previous studies have shown that the prodissoconch is retained into the juvenile phase, thus enabling juveniles to maintain a record of the larval movement. Before elemental fingerprinting can be used as a larval tracking tool, site specific signatures must be evident in the shells. As a precursor study to test the application of elemental fingerprinting to track bivalve larvae, the presence of spatial variability in shell signatures as well as the scale at which these variations occurred, were established for New Zealand conditions. Furthermore, temporal stability of the shell signatures was explored, as temporal stability is crucial if the signals of shells collected at one time are to be used as predictors of unknown samples collected at a different time.
The venerid bivalve Austrovenus stutchburyi is a common and widespread constituent of New Zealand estuarine communities and were therefore selected as the study species. The chemical signatures of entire Austrovenus stutchburyi shells were examined to determine the inter-site spatial differences in elemental fingerprints of shells and also to characterise the temporal stability of the signatures. Furthermore, shells were ablated at two reference points (the prodissoconch and most recently formed shell material) to determine the intra-shell variation in the chemical signatures. Juvenile individuals were collected from 19 sites in the North Island of New Zealand as part of the whole shell spatial study. One site (in Tauranga Harbour) was examined for the temporal study, whilst four sites were used to compare intra-shell chemical variation. Whole shells were digested and analysed as solution based samples using inductively coupled
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ABSTRACT
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plasma-mass spectrometry (ICP-MS) for the spatial and temporal studies, and by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) for the point ablation intra-shell variation study.
Results showed that shell concentrations were sufficiently different to yield a classification success of 68% over 19 sites, however the classification success markedly increased as the number of sites included in the analysis decreased (e.g. 12 sites = 75%, 10 sites = 84%, 5 sites = 90%, 3 sites = 95%). Shells were successfully classified across all of the spatial scales that were tested (approximately 10 km to 1150 km). Temporal stability in chemical signatures was observed over a 44 day period. The chemical signatures were not correlated with ambient temperature or salinity, however more vigorous sampling is needed to accurately assess the relationship between shell elemental incorporation and environmental conditions. Intra-shell variation was also observed for some of the shells analysed from two of the four sites. These results were promising and indicated that there may be chemical variations between the larval shells and the more recently formed shell material, thus suggesting the possibility of external recruitment.
The results from this study emphasised the potential for the application of elemental fingerprinting techniques to track and better understand the larval transport and population connectivity for New Zealand invertebrate species, however more research is required before elemental fingerprinting can effectively be applied to New Zealand invertebrate species. With a fundamental understanding of the origin of bivalve recruits, restoration efforts following estuarine disturbance events can be effectively employed.

text: The application of elemental fingerprinting techniques to identify population connectivity using austrovenus stutchburyi recruits The density, distribution and dynamics of benthic bivalve populations are believed to be largely determined by the planktonic larval phase of the life history. As the hard parts of larvae, such as the prodissoconch (larval shell), develop and grow, ambient environmental conditions are recorded as chemical signatures (elemental fingerprints). If the chemical signals of reference sites are known, the larval signatures can be matched to reference sites, hereby reconstructing the origin of the larvae. The collection and identification of larval bivalves is extremely difficult, however, previous studies have shown that the prodissoconch is retained into the juvenile phase, thus enabling juveniles to maintain a record of the larval movement. Before elemental fingerprinting can be used as a larval tracking tool, site specific signatures must be evident in the shells. As a precursor study to test the application of elemental fingerprinting to track bivalve larvae, the presence of spatial variability in shell signatures as well as the scale at which these variations occurred, were established for New Zealand conditions. Furthermore, temporal stability of the shell signatures was explored, as temporal stability is crucial if the signals of shells collected at one time are to be used as predictors of unknown samples collected at a different time.
The venerid bivalve Austrovenus stutchburyi is a common and widespread constituent of New Zealand estuarine communities and were therefore selected as the study species. The chemical signatures of entire Austrovenus stutchburyi shells were examined to determine the inter-site spatial differences in elemental fingerprints of shells and also to characterise the temporal stability of the signatures. Furthermore, shells were ablated at two reference points (the prodissoconch and most recently formed shell material) to determine the intra-shell variation in the chemical signatures. Juvenile individuals were collected from 19 sites in the North Island of New Zealand as part of the whole shell spatial study. One site (in Tauranga Harbour) was examined for the temporal study, whilst four sites were used to compare intra-shell chemical variation. Whole shells were digested and analysed as solution based samples using inductively coupled
ii
ABSTRACT
iii
plasma-mass spectrometry (ICP-MS) for the spatial and temporal studies, and by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) for the point ablation intra-shell variation study.
Results showed that shell concentrations were sufficiently different to yield a classification success of 68% over 19 sites, however the classification success markedly increased as the number of sites included in the analysis decreased (e.g. 12 sites = 75%, 10 sites = 84%, 5 sites = 90%, 3 sites = 95%). Shells were successfully classified across all of the spatial scales that were tested (approximately 10 km to 1150 km). Temporal stability in chemical signatures was observed over a 44 day period. The chemical signatures were not correlated with ambient temperature or salinity, however more vigorous sampling is needed to accurately assess the relationship between shell elemental incorporation and environmental conditions. Intra-shell variation was also observed for some of the shells analysed from two of the four sites. These results were promising and indicated that there may be chemical variations between the larval shells and the more recently formed shell material, thus suggesting the possibility of external recruitment.
The results from this study emphasised the potential for the application of elemental fingerprinting techniques to track and better understand the larval transport and population connectivity for New Zealand invertebrate species, however more research is required before elemental fingerprinting can effectively be applied to New Zealand invertebrate species. With a fundamental understanding of the origin of bivalve recruits, restoration efforts following estuarine disturbance events can be effectively employed.

year: 2009

title: Transformations: Anthropology, Art and the Quilt

authors: Wanigasekera, Gwenda Dorothy

subjects: Anthropology

abstract: Drawing on both anthropological and quilt literature, this thesis shows the many different ways that made objects are thought about by different groups of people.  Awareness of these differences permits a new perspective of 'Western' art and object making.  This awareness allows a space in which to consider the importance of the process of making.

Quiltmaking provides an interesting case study.  This thesis therefore describes the field of quiltmaking activity that exists in New Zealand at the present time.  This genre, as it is practised today, had its beginnings in the revival that began in this country during the 1970's.  This study will show that the main impetus of this revival did not draw on known traditions in New Zealand, but rather on a largely imported tradition that had developed in the United States of America.

Ideas about the status of quilts as art objects, comes from a mixture of influences.  The tradition of quiltmaking in the United States was already a strong one and had been through a number of revivals.  Aspects of this traditional culture influenced quiltmakers in New Zealand. Simultaneously, there was an equally strong sense of the quilt as an art object in New Zealand.  However, art entrepreneurs in the United States certainly were part of the transformation of the quilt into an art object in that country.  Their strategies of discourse and display drew on contemporary artworld ideologies and ultimately this valuation affected which quilts could be seen as 'art' in New Zealand.

Through the use of participant observation, interviews and a questionnaire, the content of this study will show the many different ways that New Zealand quiltmakers work, their aims and goals for the quilts they make, and the ways these quilts are perceived by other quilters and the wider public.  Some areas that have resulted in conflict and misunderstandings are discussed. As in any such group, conflicts and misunderstandings arise from the existence of different ways of valuing aspects of cultural activities.

NB Unlike the hard copy of this thesis the colour plates in this electronic version are placed together between the chapters and the appendices.

text: Transformations: Anthropology, Art and the Quilt Drawing on both anthropological and quilt literature, this thesis shows the many different ways that made objects are thought about by different groups of people.  Awareness of these differences permits a new perspective of 'Western' art and object making.  This awareness allows a space in which to consider the importance of the process of making.

Quiltmaking provides an interesting case study.  This thesis therefore describes the field of quiltmaking activity that exists in New Zealand at the present time.  This genre, as it is practised today, had its beginnings in the revival that began in this country during the 1970's.  This study will show that the main impetus of this revival did not draw on known traditions in New Zealand, but rather on a largely imported tradition that had developed in the United States of America.

Ideas about the status of quilts as art objects, comes from a mixture of influences.  The tradition of quiltmaking in the United States was already a strong one and had been through a number of revivals.  Aspects of this traditional culture influenced quiltmakers in New Zealand. Simultaneously, there was an equally strong sense of the quilt as an art object in New Zealand.  However, art entrepreneurs in the United States certainly were part of the transformation of the quilt into an art object in that country.  Their strategies of discourse and display drew on contemporary artworld ideologies and ultimately this valuation affected which quilts could be seen as 'art' in New Zealand.

Through the use of participant observation, interviews and a questionnaire, the content of this study will show the many different ways that New Zealand quiltmakers work, their aims and goals for the quilts they make, and the ways these quilts are perceived by other quilters and the wider public.  Some areas that have resulted in conflict and misunderstandings are discussed. As in any such group, conflicts and misunderstandings arise from the existence of different ways of valuing aspects of cultural activities.

NB Unlike the hard copy of this thesis the colour plates in this electronic version are placed together between the chapters and the appendices.

year: 2006

title: Report on the bicultural symposium at conference

authors: Masters-Awatere, Bridgette

subjects: Maori

abstract: Kia ora koutou. I decided to submit the current paper as a way to say thank you to the large group of people in attendance at the bicultural stream at the national conference in late August that was held at Waikato University. It was their continued presence and participation that served as a catalyst and motivator for this paper. I'm conscious that while there was a large number of people in the symposium, there were other streams occurring at the same time, so I thought giving an overview of the success of the symposium would be a good way to let people know who the symposium went. However, before talking specifically about the symposium, I'd like to give mention to other events of the day...

text: Report on the bicultural symposium at conference Kia ora koutou. I decided to submit the current paper as a way to say thank you to the large group of people in attendance at the bicultural stream at the national conference in late August that was held at Waikato University. It was their continued presence and participation that served as a catalyst and motivator for this paper. I'm conscious that while there was a large number of people in the symposium, there were other streams occurring at the same time, so I thought giving an overview of the success of the symposium would be a good way to let people know who the symposium went. However, before talking specifically about the symposium, I'd like to give mention to other events of the day...

year: 2007