title: Life history analysis of chinook salmon (Oncorhynchus tshawytscha) from lakes Mapourika and Paringa, West Coast, South Island, New Zealand, by otolith microchemistry

authors: Hicks, Brendan J.

abstract: Otolith microchemistry is an established technique for determining fish migrations between the sea and freshwater. The aim of our study was to determine life history patterns of chinook salmon collected from rivers and lake tributaries along the West Coast of the South Island, New Zealand using otolith microchemistry. Specifically, we compared relative concentrations of barium and strontium in salmon otoliths as a proxy of fresh and seawater migration and related this to individual fish ages. Using this approach, fish migrations between the sea and freshwater are often determined by changing patterns in strontium (Sr) and barium (Ba) concentrations across the otolith growth axis. Time spent in the sea is characterised by high relative strontium and low barium concentrations, whereas freshwater phases have relatively higher barium and low strontium concentrations. When fish move from the sea to freshwater or vice versa a pronounced change in relative concentrations is usually seen.
Ten chinook salmon were collected as carcasses or by fishing from the Hokitika and Taramakau rivers, Lake Mapourika and its tributary, MacDonalds Creek, and Lake Paringa and its tributary, Windbag Stream. A previous preliminary report investigated otoliths from 11 salmon captured in tributaries of lakes Mapourika and Paringa during 2008. This study showed lower ⁸⁷Sr/⁸⁶Sr ratios (0.707-0.709) that were interpreted as freshwater residence and higher ratios (0.710-0.712) that suggested sea residence. This approach uses strontium isotopic ratios instead of Sr and Ba elemental concentrations to determine freshwater and marine occupancy. Ratios of ⁸⁸Sr/V (vanadium) were also examined, and showed a reciprocal relationship to ratios of ⁸⁷Sr/⁸⁶Sr. All 11 otoliths examined from 2008 showed freshwater rearing followed by a period of marine residence of varying length.
Chinook salmon in our study showed a wide variety of life histories, and microchemical analysis of the otoliths partly confirmed the presumed life history of each salmon. The freshwater phase was evident from strontium concentrations, expressed as ⁸⁶Sr/⁴³Ca x 1000, of between 100 and 400 and variable barium concentrations of between 2 to 8 expressed as ¹³⁷Ba/⁴³Ca x 1000. The marine phase was characterised by high strontium concentrations of 500 to 900, with low barium concentrations, generally less than 2. Five individuals from the Hokitika and Taramakau rivers, MacDonalds Creek (L. Mapourika), and Windbag Stream (L. Paringa) exhibited normal chinook salmon life histories with early rearing in freshwater followed by an extensive period of growth to adulthood in the sea. Most salmon from MacDonalds Creek showed extensive freshwater residence, and two of these were lakelocked, with exclusively freshwater residence. A further two fish collected in May 2012 from MacDonalds Creek had lived most of their life in freshwater but showed evidence of a brief period in the sea late in life at ages 2 and 3 year respectively. Curiously, one fish from MacDonalds Creek had apparently entered a marine environment, possibly an estuary, just before its recovery as a carcass.

text: Life history analysis of chinook salmon (Oncorhynchus tshawytscha) from lakes Mapourika and Paringa, West Coast, South Island, New Zealand, by otolith microchemistry Otolith microchemistry is an established technique for determining fish migrations between the sea and freshwater. The aim of our study was to determine life history patterns of chinook salmon collected from rivers and lake tributaries along the West Coast of the South Island, New Zealand using otolith microchemistry. Specifically, we compared relative concentrations of barium and strontium in salmon otoliths as a proxy of fresh and seawater migration and related this to individual fish ages. Using this approach, fish migrations between the sea and freshwater are often determined by changing patterns in strontium (Sr) and barium (Ba) concentrations across the otolith growth axis. Time spent in the sea is characterised by high relative strontium and low barium concentrations, whereas freshwater phases have relatively higher barium and low strontium concentrations. When fish move from the sea to freshwater or vice versa a pronounced change in relative concentrations is usually seen.
Ten chinook salmon were collected as carcasses or by fishing from the Hokitika and Taramakau rivers, Lake Mapourika and its tributary, MacDonalds Creek, and Lake Paringa and its tributary, Windbag Stream. A previous preliminary report investigated otoliths from 11 salmon captured in tributaries of lakes Mapourika and Paringa during 2008. This study showed lower ⁸⁷Sr/⁸⁶Sr ratios (0.707-0.709) that were interpreted as freshwater residence and higher ratios (0.710-0.712) that suggested sea residence. This approach uses strontium isotopic ratios instead of Sr and Ba elemental concentrations to determine freshwater and marine occupancy. Ratios of ⁸⁸Sr/V (vanadium) were also examined, and showed a reciprocal relationship to ratios of ⁸⁷Sr/⁸⁶Sr. All 11 otoliths examined from 2008 showed freshwater rearing followed by a period of marine residence of varying length.
Chinook salmon in our study showed a wide variety of life histories, and microchemical analysis of the otoliths partly confirmed the presumed life history of each salmon. The freshwater phase was evident from strontium concentrations, expressed as ⁸⁶Sr/⁴³Ca x 1000, of between 100 and 400 and variable barium concentrations of between 2 to 8 expressed as ¹³⁷Ba/⁴³Ca x 1000. The marine phase was characterised by high strontium concentrations of 500 to 900, with low barium concentrations, generally less than 2. Five individuals from the Hokitika and Taramakau rivers, MacDonalds Creek (L. Mapourika), and Windbag Stream (L. Paringa) exhibited normal chinook salmon life histories with early rearing in freshwater followed by an extensive period of growth to adulthood in the sea. Most salmon from MacDonalds Creek showed extensive freshwater residence, and two of these were lakelocked, with exclusively freshwater residence. A further two fish collected in May 2012 from MacDonalds Creek had lived most of their life in freshwater but showed evidence of a brief period in the sea late in life at ages 2 and 3 year respectively. Curiously, one fish from MacDonalds Creek had apparently entered a marine environment, possibly an estuary, just before its recovery as a carcass.

year: 2013

title: Synthesis and characterisation of low-cost biopolymeric/mineral composite systems and evaluation of their potential application for heavy metal removal

authors: Zia, Zahida

subjects: Water treatment

abstract: Heavy metal pollution and waste management are two major environmental problems faced in the world today. Anthropogenic sources of heavy metals, especially effluent from industries, are serious environmental and health concerns by polluting surface and ground waters. Similarly, on a global scale, thousands of tonnes of industrial and agricultural waste are discarded into the environment annually. There are several conventional methods to treat industrial effluents, including reverse osmosis, oxidation, filtration, flotation, chemical precipitation, ion exchange resins and adsorption. Among them, adsorption and ion exchange are known to be effective mechanisms for removing heavy metal pollution, especially if low-cost materials can be used. 
This thesis was a study into materials that can be used to remove heavy metals from water using low-cost feedstock materials. The synthesis of low-cost composite matrices from agricultural and industrial by-products and low-cost organic and mineral sources was carried out. The feedstock materials being considered include chitosan (generated from industrial seafood waste), coir fibre (an agricultural by-product), spent coffee grounds (a by-product from coffee machines), hydroxyapatite (from bovine bone), and naturally sourced aluminosilicate minerals such as zeolite. 
The novel composite adsorbents were prepared using commercially sourced HAp and bovine sourced HAp, with two types of adsorbents being synthesized, including two- and three-component composites. Standard synthetic methods such as precipitation were developed to synthesize these materials, followed by characterization of their structural, physical, and chemical properties (by using FTIR, TGA, SEM, EDX and XRD). 
The synthesized materials were then evaluated for their ability to remove metal ions from solutions of heavy metals using single-metal ion type and two-metal ion type solution systems, using the model ion solutions, with quantification of their removal efficiency. It was followed by experimentation using the synthesized adsorbents for metal ion removal in complex systems such as an industrial input stream solution system obtained from a local timber treatment company. 
Two-component composites were considered as control composites to compare the removal efficiency of the three-component composites against.  The heavy metal removal experiments were conducted under a range of experimental conditions (e.g., pH, sorbent dose, initial metal ion concentration, time of contact). Of the four metal ion systems considered in this study (Cd²⁺, Pb²⁺, Cu²⁺ and Cr as chromate ions), Pb²⁺ ion removal by the composites was found to be the highest in single-metal and two-metal ion type solution systems, while chromate ion removal was found to be the lowest. The bovine bone-based hydroxyapatite (bHAp) composites were more efficient at removing the metal cations than composites formed from a commercially sourced hydroxyapatite (cHAp). 
In industrial input stream solution systems (containing Cu, Cr and As), the Cu²⁺ ion removal was the highest, which aligned with the observations recorded in the single and two-metal ion type solution systems. Arsenate ion was removed to a higher extent than chromate ion using the three-component composites, while the removal of chromate ion was found to be higher than arsenate ion when using the two-component composites (i.e., the control system). 
The project also aimed to elucidate the removal mechanisms of these synthesized composite materials by using appropriate adsorption and kinetic models. The adsorption of metal ions exhibited a range of adsorption behaviours as both the models (Langmuir and Freundlich) were found to fit most of the data recorded in different adsorption systems studied. The pseudo-second-order model was found to be the best fitted to describe the kinetics of heavy metal ion adsorption in all the composite adsorbent systems studied, in single-metal ion type and two-metal ion type solution systems. The ion-exchange mechanism was considered as one of the dominant mechanisms for the removal of cations (in single-metal and two-metal ion type solution systems) and arsenate ions (in industrial input stream solution systems) along with other adsorption mechanisms.  In contrast, electrostatic attractions were considered to be the dominant mechanism of removal for chromate ions.

text: Synthesis and characterisation of low-cost biopolymeric/mineral composite systems and evaluation of their potential application for heavy metal removal Heavy metal pollution and waste management are two major environmental problems faced in the world today. Anthropogenic sources of heavy metals, especially effluent from industries, are serious environmental and health concerns by polluting surface and ground waters. Similarly, on a global scale, thousands of tonnes of industrial and agricultural waste are discarded into the environment annually. There are several conventional methods to treat industrial effluents, including reverse osmosis, oxidation, filtration, flotation, chemical precipitation, ion exchange resins and adsorption. Among them, adsorption and ion exchange are known to be effective mechanisms for removing heavy metal pollution, especially if low-cost materials can be used. 
This thesis was a study into materials that can be used to remove heavy metals from water using low-cost feedstock materials. The synthesis of low-cost composite matrices from agricultural and industrial by-products and low-cost organic and mineral sources was carried out. The feedstock materials being considered include chitosan (generated from industrial seafood waste), coir fibre (an agricultural by-product), spent coffee grounds (a by-product from coffee machines), hydroxyapatite (from bovine bone), and naturally sourced aluminosilicate minerals such as zeolite. 
The novel composite adsorbents were prepared using commercially sourced HAp and bovine sourced HAp, with two types of adsorbents being synthesized, including two- and three-component composites. Standard synthetic methods such as precipitation were developed to synthesize these materials, followed by characterization of their structural, physical, and chemical properties (by using FTIR, TGA, SEM, EDX and XRD). 
The synthesized materials were then evaluated for their ability to remove metal ions from solutions of heavy metals using single-metal ion type and two-metal ion type solution systems, using the model ion solutions, with quantification of their removal efficiency. It was followed by experimentation using the synthesized adsorbents for metal ion removal in complex systems such as an industrial input stream solution system obtained from a local timber treatment company. 
Two-component composites were considered as control composites to compare the removal efficiency of the three-component composites against.  The heavy metal removal experiments were conducted under a range of experimental conditions (e.g., pH, sorbent dose, initial metal ion concentration, time of contact). Of the four metal ion systems considered in this study (Cd²⁺, Pb²⁺, Cu²⁺ and Cr as chromate ions), Pb²⁺ ion removal by the composites was found to be the highest in single-metal and two-metal ion type solution systems, while chromate ion removal was found to be the lowest. The bovine bone-based hydroxyapatite (bHAp) composites were more efficient at removing the metal cations than composites formed from a commercially sourced hydroxyapatite (cHAp). 
In industrial input stream solution systems (containing Cu, Cr and As), the Cu²⁺ ion removal was the highest, which aligned with the observations recorded in the single and two-metal ion type solution systems. Arsenate ion was removed to a higher extent than chromate ion using the three-component composites, while the removal of chromate ion was found to be higher than arsenate ion when using the two-component composites (i.e., the control system). 
The project also aimed to elucidate the removal mechanisms of these synthesized composite materials by using appropriate adsorption and kinetic models. The adsorption of metal ions exhibited a range of adsorption behaviours as both the models (Langmuir and Freundlich) were found to fit most of the data recorded in different adsorption systems studied. The pseudo-second-order model was found to be the best fitted to describe the kinetics of heavy metal ion adsorption in all the composite adsorbent systems studied, in single-metal ion type and two-metal ion type solution systems. The ion-exchange mechanism was considered as one of the dominant mechanisms for the removal of cations (in single-metal and two-metal ion type solution systems) and arsenate ions (in industrial input stream solution systems) along with other adsorption mechanisms.  In contrast, electrostatic attractions were considered to be the dominant mechanism of removal for chromate ions.

year: 2022

title: Tapuwaekiwi tapuaeharuru taiharuru te Whakatōhea toheraoa: Connecting to my iwi and reclamation of identity through endurance running grounded in iwi narratives and tikanga/culture.

authors: Helyar-Magill, Nicholas

abstract: This thesis explores the intersection of endurance, whakapapa, and cultural reconnection through the lens of ultra-marathon running and Te Whakatōhea tīpuna pūrākau. By weaving together personal narratives, historical contexts, and contemporary athletic practices, this research examines the role of endurance sports as a pathway for cultural revitalisation and identity reclamation among Māori athletes.
Endurance is a fundamental characteristic of Te Whakatōhea, embodied not only in the physical feats of long-distance running but also in the iwi's historical resilience through colonisation, raupatu, and cultural disconnection. This research positions ultra-marathon running as both a metaphor and a mechanism for reclaiming whakapapa, fostering well-being, and strengthening the connection between Māori athletes and te ao Māori. Drawing upon Kaupapa Māori methodology, qualitative research methods, and tikanga Māori principles, this research seeks to decolonise endurance sports by embedding iwi narratives, tikanga, and mana whenua engagement into the sport of ultra-running.
A central aim of this research is to develop a culturally grounded framework that integrates Te Whakatōhea pūrākau and tikanga into ultra-marathon events. This framework envisions a race that traverses ancestral pathways, acknowledges the whenua and mana whenua, and fosters a culturally safe environment for Māori athletes. The research questions driving this thesis examine the historical endurance of Te Whakatōhea, the impact of colonisation on Māori participation in endurance sports, and the potential for tikanga to be embedded in ultra-marathon events.
The findings of this research reveal that endurance is deeply woven into the whakapapa of Te Whakatōhea and that ultra-marathon running serves as a powerful means of reconnecting with iwi identity, whenua, and te ao Māori. Through interviews with Māori endurance athletes and an exploration of iwi narratives, this research highlights the transformative potential of culturally embedded endurance sports. Furthermore, the research identifies barriers to Māori participation in ultra-marathons, including historical disenfranchisement from traditional athletic spaces and the predominance of Pākehā worldviews in endurance sports. Addressing these barriers, this thesis proposes a tikanga-based model that seeks to attract greater Māori
participation by integrating kaupapa Māori principles into the design, organisation, and execution of ultra-marathon events.
This research is also a personal journey of endurance and reconnection, reflecting on my own whakapapa as a descendant of Te Whakatōhea and an ultra-marathon runner. Raised outside of the iwi rohe, my path of reclaiming identity through sport mirrors the broader themes of cultural endurance and revitalisation explored in this thesis. By engaging with iwi histories, participating in kaupapa Māori spaces, and embedding tikanga into my athletic practice, I have sought to bridge the gap between past and present, creating a future where Māori endurance athletes can thrive within a culturally affirming space.
Ultimately, this thesis contributes to the growing discourse on Indigenous endurance sports, cultural resilience, and decolonial approaches to athletic participation. It affirms that ultra-marathon running, when grounded in whakapapa and tikanga, has the potential to serve as a tool for cultural reconnection, healing, and identity reclamation for Māori athletes and Te Whakatōhea whānau.

text: Tapuwaekiwi tapuaeharuru taiharuru te Whakatōhea toheraoa: Connecting to my iwi and reclamation of identity through endurance running grounded in iwi narratives and tikanga/culture. This thesis explores the intersection of endurance, whakapapa, and cultural reconnection through the lens of ultra-marathon running and Te Whakatōhea tīpuna pūrākau. By weaving together personal narratives, historical contexts, and contemporary athletic practices, this research examines the role of endurance sports as a pathway for cultural revitalisation and identity reclamation among Māori athletes.
Endurance is a fundamental characteristic of Te Whakatōhea, embodied not only in the physical feats of long-distance running but also in the iwi's historical resilience through colonisation, raupatu, and cultural disconnection. This research positions ultra-marathon running as both a metaphor and a mechanism for reclaiming whakapapa, fostering well-being, and strengthening the connection between Māori athletes and te ao Māori. Drawing upon Kaupapa Māori methodology, qualitative research methods, and tikanga Māori principles, this research seeks to decolonise endurance sports by embedding iwi narratives, tikanga, and mana whenua engagement into the sport of ultra-running.
A central aim of this research is to develop a culturally grounded framework that integrates Te Whakatōhea pūrākau and tikanga into ultra-marathon events. This framework envisions a race that traverses ancestral pathways, acknowledges the whenua and mana whenua, and fosters a culturally safe environment for Māori athletes. The research questions driving this thesis examine the historical endurance of Te Whakatōhea, the impact of colonisation on Māori participation in endurance sports, and the potential for tikanga to be embedded in ultra-marathon events.
The findings of this research reveal that endurance is deeply woven into the whakapapa of Te Whakatōhea and that ultra-marathon running serves as a powerful means of reconnecting with iwi identity, whenua, and te ao Māori. Through interviews with Māori endurance athletes and an exploration of iwi narratives, this research highlights the transformative potential of culturally embedded endurance sports. Furthermore, the research identifies barriers to Māori participation in ultra-marathons, including historical disenfranchisement from traditional athletic spaces and the predominance of Pākehā worldviews in endurance sports. Addressing these barriers, this thesis proposes a tikanga-based model that seeks to attract greater Māori
participation by integrating kaupapa Māori principles into the design, organisation, and execution of ultra-marathon events.
This research is also a personal journey of endurance and reconnection, reflecting on my own whakapapa as a descendant of Te Whakatōhea and an ultra-marathon runner. Raised outside of the iwi rohe, my path of reclaiming identity through sport mirrors the broader themes of cultural endurance and revitalisation explored in this thesis. By engaging with iwi histories, participating in kaupapa Māori spaces, and embedding tikanga into my athletic practice, I have sought to bridge the gap between past and present, creating a future where Māori endurance athletes can thrive within a culturally affirming space.
Ultimately, this thesis contributes to the growing discourse on Indigenous endurance sports, cultural resilience, and decolonial approaches to athletic participation. It affirms that ultra-marathon running, when grounded in whakapapa and tikanga, has the potential to serve as a tool for cultural reconnection, healing, and identity reclamation for Māori athletes and Te Whakatōhea whānau.

year: 2024