title: Hydrodynamic modelling of Lake Whangape and Lake Waahi

authors: Jones, Hannah Frances Emily

abstract: The University of Waikato was contracted by Waikato Regional Council to develop hydrodynamic models for Lake Whangape and Lake Waahi. The models are intended to provide a basis for future water quality modelling to inform the restoration of habitat for native fish and the management of pest fish populations. Lakes Whangape and Waahi are shallow, highly eutrophic lakes in the lower Waikato River basin. They contain significant populations of native fish species, such as īnanga (Galaxias maculatus), longfinned and shortfinned eel (Anguilla dieffenbachia and Anguilla australis). They also contain a number of exotic pest fish, such as mosquito fish (Gambusia affinis), koi carp (Cyprinus carpio) and goldfish (Carassius auratus), that can contribute significantly to water quality problems. For both lakes, bathymetry was combined with LiDAR (Light Detection and Ranging) data to create a topographic- bathymetric Digital Elevation Map (EDM) that provided the basis for the hydrodynamic model grids and may also be used for GIS modelling of potential fish habitat. The DEMs revealed the presence of stopbanks around both lakes that appear to restrict floodplain habitat significantly. Hydrodynamic models for Lakes Whangape and Waahi were developed using available measured or synthesised data. While there was insufficient data available for formal model calibration and validation, year-long model simulations were analysed to ensure that seasonal variability in water levels and temperature were represented. The model used, Delft3D-FLOW, is open-source, developed by Deltares (The Netherlands), and can be coupled to open-source ecological and water quality models (e.g. Delft-WAQ), thus enabling future water quality modelling applications.

text: Hydrodynamic modelling of Lake Whangape and Lake Waahi The University of Waikato was contracted by Waikato Regional Council to develop hydrodynamic models for Lake Whangape and Lake Waahi. The models are intended to provide a basis for future water quality modelling to inform the restoration of habitat for native fish and the management of pest fish populations. Lakes Whangape and Waahi are shallow, highly eutrophic lakes in the lower Waikato River basin. They contain significant populations of native fish species, such as īnanga (Galaxias maculatus), longfinned and shortfinned eel (Anguilla dieffenbachia and Anguilla australis). They also contain a number of exotic pest fish, such as mosquito fish (Gambusia affinis), koi carp (Cyprinus carpio) and goldfish (Carassius auratus), that can contribute significantly to water quality problems. For both lakes, bathymetry was combined with LiDAR (Light Detection and Ranging) data to create a topographic- bathymetric Digital Elevation Map (EDM) that provided the basis for the hydrodynamic model grids and may also be used for GIS modelling of potential fish habitat. The DEMs revealed the presence of stopbanks around both lakes that appear to restrict floodplain habitat significantly. Hydrodynamic models for Lakes Whangape and Waahi were developed using available measured or synthesised data. While there was insufficient data available for formal model calibration and validation, year-long model simulations were analysed to ensure that seasonal variability in water levels and temperature were represented. The model used, Delft3D-FLOW, is open-source, developed by Deltares (The Netherlands), and can be coupled to open-source ecological and water quality models (e.g. Delft-WAQ), thus enabling future water quality modelling applications.

year: 2014

title: Grass carp and incidental invaders from aquaculture: a study of impacts on zooplankton communities and invader origins

authors: Branford, Suzanne Nicola

subjects: Biological Invasions

abstract: The movement of fish from aquaculture facilities has led to invasions of non-native species globally, including of ‘hitch-hiking’ species, resulting in impacts on the composition of communities in recipient ecosystems. This thesis employs both community scale analysis and sensitive molecular techniques to assess the effects of grass carp translocations on zooplankton communities and to determine the origins of an incidental non-native invader. 

In the first component, I tested the effects of grass carp translocations from aquaculture facilities on ponds in the Auckland region, New Zealand. Zooplankton community composition was quantified in 34 ponds that had been subject to grass carp release and 31 which had no grass carp introductions. A significant difference in zooplankton community composition was observed between ponds that had received grass carp translocations and those that had not. Differences in zooplankton community composition between ponds with and without carp releases were attributable to: 1) the establishment of zooplankton originating from aquaculture ponds, including non-native species; and 2) the effects of grass carp activity, through habitat modification. Effective measures to curb the proliferation of non-native taxa within aquaculture facilities, and to mitigate the unintentional movement of non-native taxa with translocations from these facilities, are required to reduce future introductions.

In the second component of this thesis I used a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene to more precisely identify the origins of invasions of freshwater calanoid copepod Skistodiaptomus pallidus (Herrick 1879). This was applied to populations sampled from within New Zealand, which have been linked to the release of fish from aquaculture facilities, and to populations found in Germany, which have possible links to a shipping vector. The S. pallidus COI sequences placed both the New Zealand and German specimens with those from the most easterly regions of the USA (e.g., New York, Virginia and Georgia). However, several haplotypes were found to be divergent between the New Zealand and German populations, indicating the exact sources of the introductions were likely different for each country. German sequences had greater haplotype diversity than those from New Zealand, supporting the suggestions of a shipping related vector of introduction to Germany. Both German and New Zealand populations contained haplotypes that were closely related to North American sequence records. However, further sampling of the native range will be required to determine the exact origin of the non-indigenous S. pallidus populations. With this additional information it may also be possible to determine more precisely the vectors of introduction. 

Collectively, the two research chapters provide a broader understanding of invasion processes and the effects of grass carp translocations on the zooplankton communities within recipient ponds in New Zealand. My research has immediate application in the re-evaluation of fish translocation management practises and impacts.

text: Grass carp and incidental invaders from aquaculture: a study of impacts on zooplankton communities and invader origins The movement of fish from aquaculture facilities has led to invasions of non-native species globally, including of ‘hitch-hiking’ species, resulting in impacts on the composition of communities in recipient ecosystems. This thesis employs both community scale analysis and sensitive molecular techniques to assess the effects of grass carp translocations on zooplankton communities and to determine the origins of an incidental non-native invader. 

In the first component, I tested the effects of grass carp translocations from aquaculture facilities on ponds in the Auckland region, New Zealand. Zooplankton community composition was quantified in 34 ponds that had been subject to grass carp release and 31 which had no grass carp introductions. A significant difference in zooplankton community composition was observed between ponds that had received grass carp translocations and those that had not. Differences in zooplankton community composition between ponds with and without carp releases were attributable to: 1) the establishment of zooplankton originating from aquaculture ponds, including non-native species; and 2) the effects of grass carp activity, through habitat modification. Effective measures to curb the proliferation of non-native taxa within aquaculture facilities, and to mitigate the unintentional movement of non-native taxa with translocations from these facilities, are required to reduce future introductions.

In the second component of this thesis I used a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene to more precisely identify the origins of invasions of freshwater calanoid copepod Skistodiaptomus pallidus (Herrick 1879). This was applied to populations sampled from within New Zealand, which have been linked to the release of fish from aquaculture facilities, and to populations found in Germany, which have possible links to a shipping vector. The S. pallidus COI sequences placed both the New Zealand and German specimens with those from the most easterly regions of the USA (e.g., New York, Virginia and Georgia). However, several haplotypes were found to be divergent between the New Zealand and German populations, indicating the exact sources of the introductions were likely different for each country. German sequences had greater haplotype diversity than those from New Zealand, supporting the suggestions of a shipping related vector of introduction to Germany. Both German and New Zealand populations contained haplotypes that were closely related to North American sequence records. However, further sampling of the native range will be required to determine the exact origin of the non-indigenous S. pallidus populations. With this additional information it may also be possible to determine more precisely the vectors of introduction. 

Collectively, the two research chapters provide a broader understanding of invasion processes and the effects of grass carp translocations on the zooplankton communities within recipient ponds in New Zealand. My research has immediate application in the re-evaluation of fish translocation management practises and impacts.

year: 2016

title: E Toru Ngā Reo: A Case Study of a Spanish Language Programme in a Kura Kaupapa Māori

authors: Flavell, William

subjects: Kaupapa Maori Research

abstract: Learning Languages is a new area in the 2007 New Zealand Curriculum.  However there have not been many studies in this subject.  Kura Kaupapa Māori, established in 1985 in New Zealand with over 6,000 students currently attending, have English language programmes (Hill, 2010), however few, if any, studies of the teaching of other languages have been conducted.  The purpose of this study was to describe and evaluate an additional international language programme at a Kura Kaupapa Māori.

This qualitative case study describes the views of the Principal, five teachers, five students and three parents of a Kura Kaupapa Māori about an additional Spanish language programme. The primary means of gathering data was through individual semi-structured interviews.  Interviews were used to collect data in the areas of identifying the attitudes of the participants towards learning an additional international language, the perceived benefits, if any, of learning an additional international language and if there is a relationship between the learning of an  additional international language, and Kaupapa Māori.  The narrative data was transcribed, coded and categorised into four themes related to the research questions.  

 The success of this Spanish language programme can be understood in terms of several factors such as whānau support, programme leadership, quality teachers, international excursions and positive attitudes to foreign language learning.  

These findings will contribute to literature concerning additional language learning programmes, specifically those based in indigenous language immersion settings and they will also provide useful information and ideas which other Kura Kaupapa Māori can take advantage of when implementing additional international language learning programmes.

text: E Toru Ngā Reo: A Case Study of a Spanish Language Programme in a Kura Kaupapa Māori Learning Languages is a new area in the 2007 New Zealand Curriculum.  However there have not been many studies in this subject.  Kura Kaupapa Māori, established in 1985 in New Zealand with over 6,000 students currently attending, have English language programmes (Hill, 2010), however few, if any, studies of the teaching of other languages have been conducted.  The purpose of this study was to describe and evaluate an additional international language programme at a Kura Kaupapa Māori.

This qualitative case study describes the views of the Principal, five teachers, five students and three parents of a Kura Kaupapa Māori about an additional Spanish language programme. The primary means of gathering data was through individual semi-structured interviews.  Interviews were used to collect data in the areas of identifying the attitudes of the participants towards learning an additional international language, the perceived benefits, if any, of learning an additional international language and if there is a relationship between the learning of an  additional international language, and Kaupapa Māori.  The narrative data was transcribed, coded and categorised into four themes related to the research questions.  

 The success of this Spanish language programme can be understood in terms of several factors such as whānau support, programme leadership, quality teachers, international excursions and positive attitudes to foreign language learning.  

These findings will contribute to literature concerning additional language learning programmes, specifically those based in indigenous language immersion settings and they will also provide useful information and ideas which other Kura Kaupapa Māori can take advantage of when implementing additional international language learning programmes.

year: 2012