title: Canine (Canis familiaris) scent detection of invasive brown bullhead catfish (Ameiurus nebulosus) in water samples, and the effects of sample preservation

authors: Denby, Renee

abstract: Brown bullhead catfish (Ameiurus nebulosus) are an invasive freshwater fish widely recognised as a threat to New Zealand’s aquatic ecosystems. Early detection of new incursions increases the chances of eradication or control, but current survey methods such as netting and electrofishing are expensive and time consuming when fish are at low abundances. Domestic dogs (Canis familiaris) have previously demonstrated the ability to detect the presence of catfish in laboratory water samples, while discriminating against non-target species. The aim of this research was to investigate whether scent detection dogs could plausibly be employed in aquatic biosecurity programmes. The first experiment used a probe design to determine the scent-detection limits for catfish biomass under laboratory conditions. Water samples taken from tanks containing a standard catfish biomass concentration of 15.5 g/L (equivalent to 38,700 kg/ha) were assessed by the dogs and progressively diluted following the successful attainment of identification and discrimination criteria. All three participating dogs were able to detect the presence of catfish at biomass concentrations ≤12.6 kg/ha, with one dog achieving 4.6 kg/ha. Concurrently, the dogs were also able to successfully discriminate against a goldfish (Carassius auratus) distractor scent indicating that they are able to distinguish specific species of fish in the environment. The effects of sample preservation on dogs’ ability to identify and discriminate target scents have rarely been investigated. In practice, field samples from the environment would likely necessitate the preservation of samples prior to assessment by dogs. A second study used a repeated-measures reversal design to investigate dogs’ abilities to detect catfish at a standard biomass concentration of 310 kg/ha which had been refrigerated or frozen for up to 1-week. No statistically significant difference in hit rates between unpreserved (baseline 1: 93%, baseline 2: 98%), refrigerated (97%), and frozen (96%) samples was apparent; (F(3, 6) = 2.061502, p = 0.2069). These results indicate that dogs are capable of detecting and discriminating the scent of catfish at biomass concentrations typical of many freshwater ecosystems in the Waikato region. Further, limited periods of freezing or refrigeration appear to have no significant effect on the scent-detection abilities of dogs. Future research needs to be conducted with field samples from lakes and could explore the effects of preservation on low biomass concentrations. The results from this study are promising for the potential future employment of scent detection dogs in aquatic biosecurity monitoring.

text: Canine (Canis familiaris) scent detection of invasive brown bullhead catfish (Ameiurus nebulosus) in water samples, and the effects of sample preservation Brown bullhead catfish (Ameiurus nebulosus) are an invasive freshwater fish widely recognised as a threat to New Zealand’s aquatic ecosystems. Early detection of new incursions increases the chances of eradication or control, but current survey methods such as netting and electrofishing are expensive and time consuming when fish are at low abundances. Domestic dogs (Canis familiaris) have previously demonstrated the ability to detect the presence of catfish in laboratory water samples, while discriminating against non-target species. The aim of this research was to investigate whether scent detection dogs could plausibly be employed in aquatic biosecurity programmes. The first experiment used a probe design to determine the scent-detection limits for catfish biomass under laboratory conditions. Water samples taken from tanks containing a standard catfish biomass concentration of 15.5 g/L (equivalent to 38,700 kg/ha) were assessed by the dogs and progressively diluted following the successful attainment of identification and discrimination criteria. All three participating dogs were able to detect the presence of catfish at biomass concentrations ≤12.6 kg/ha, with one dog achieving 4.6 kg/ha. Concurrently, the dogs were also able to successfully discriminate against a goldfish (Carassius auratus) distractor scent indicating that they are able to distinguish specific species of fish in the environment. The effects of sample preservation on dogs’ ability to identify and discriminate target scents have rarely been investigated. In practice, field samples from the environment would likely necessitate the preservation of samples prior to assessment by dogs. A second study used a repeated-measures reversal design to investigate dogs’ abilities to detect catfish at a standard biomass concentration of 310 kg/ha which had been refrigerated or frozen for up to 1-week. No statistically significant difference in hit rates between unpreserved (baseline 1: 93%, baseline 2: 98%), refrigerated (97%), and frozen (96%) samples was apparent; (F(3, 6) = 2.061502, p = 0.2069). These results indicate that dogs are capable of detecting and discriminating the scent of catfish at biomass concentrations typical of many freshwater ecosystems in the Waikato region. Further, limited periods of freezing or refrigeration appear to have no significant effect on the scent-detection abilities of dogs. Future research needs to be conducted with field samples from lakes and could explore the effects of preservation on low biomass concentrations. The results from this study are promising for the potential future employment of scent detection dogs in aquatic biosecurity monitoring.

year: 2021

title: Topical gradients in plant ecology

authors: Laughlin, Daniel C.

subjects: Community ecology

abstract: Plant ecology spans multiple levels of biological organization and spatio-temporal scales, and over four dozen plant ecology textbooks have been published since Warming's (1895) 'Oecology of Plants.' With increasing emphasis on specialization, students and teachers can feel paralyzed by the vast literature, and as such may lack an adequate appreciation of the history of the field. The objective of this study was to derive a comprehensive set of topics that are covered in plant ecology textbooks, and to ask (1) what are the most important topical gradients among textbooks, and (2) has the emphasis of topics changed over time? The NMS ordination determined that the first gradient represented a clear contrast in emphasis on physiological ecology versus community ecology. The second gradient represented a contrast in emphasis on abiotic environmental factors versus biotic factors. Negative interactions, growth, demography, gas exchange, mineral nutrition, stress, diversity, disturbance, herbivory, paleoecology, ecosystem ecology, pollution, and global change have increased in emphasis over time. The increasing reliance on data and the number of authors per textbook illustrates how the discipline has matured into a rigorous quantitative science that requires a diversity of specializations. These results can be used to inform the development of curricula within a single course or across several years of study, and to assist the development of new and revised textbooks. Plant ecologists need to be familiar with this core set of topics in addition to becoming an expert in a few of them.

text: Topical gradients in plant ecology Plant ecology spans multiple levels of biological organization and spatio-temporal scales, and over four dozen plant ecology textbooks have been published since Warming's (1895) 'Oecology of Plants.' With increasing emphasis on specialization, students and teachers can feel paralyzed by the vast literature, and as such may lack an adequate appreciation of the history of the field. The objective of this study was to derive a comprehensive set of topics that are covered in plant ecology textbooks, and to ask (1) what are the most important topical gradients among textbooks, and (2) has the emphasis of topics changed over time? The NMS ordination determined that the first gradient represented a clear contrast in emphasis on physiological ecology versus community ecology. The second gradient represented a contrast in emphasis on abiotic environmental factors versus biotic factors. Negative interactions, growth, demography, gas exchange, mineral nutrition, stress, diversity, disturbance, herbivory, paleoecology, ecosystem ecology, pollution, and global change have increased in emphasis over time. The increasing reliance on data and the number of authors per textbook illustrates how the discipline has matured into a rigorous quantitative science that requires a diversity of specializations. These results can be used to inform the development of curricula within a single course or across several years of study, and to assist the development of new and revised textbooks. Plant ecologists need to be familiar with this core set of topics in addition to becoming an expert in a few of them.

year: 2012

title: A criterion referenced analysis and evaluation of the processes involved in formulating a Māori language regeneration strategy for Whakamārama marae

authors: Lewis, Roger Brian

subjects: critical success factors

abstract: The quality of the processes involved in language regeneration strategy formation is critical to the creation of an effective language regeneration strategy and this, in turn, is critical to the achievement of successful language regeneration outcomes. The overall aim of this research project was to evaluate, using a range of effectiveness criteria, the processes involved in the creation of a marae-based te reo Māori regeneration strategy in the hope that others involved in similar projects in the future would benefit and in the hope that the Whakamārama whānau will themselves derive benefit from it in reviewing what has already been achieved. In Chapter 1, the background to the research project and its rationale are outlined
and the research questions and research methods are introduced. Chapter 2 provides a critical review of selected literature in the area of strategic planning aspects of language regeneration and relevant aspects of mātauranga Māori. Using an ethnographic approach, the processes and immediate outcomes (in terms of a
survey report and a regeneration plan for Whakamārama marae) of the language regeneration project are outlined in Chapter 3. In Chapter 4, effectiveness criteria are derived on the basis of the literature review in Chapter 2. These include criteria relating to leadership, participation, Kaupapa Māori values, environmental
analysis and outcomes. The criteria are then applied to the analysis and evaluation of the processes and outcomes outlined in Chapter 3 in order to identify their strengths and weaknesses. The overall conclusion is that Whakamārama's
language regeneration activities to date can be regarded as successful in many ways, including the fact that they have resulted in the production of high quality documentation that is widely appreciated by the whānau in the form of a maraebased language survey and a marae-based te reo Māori regeneration plan. Working voluntarily and often under difficult circumstances, core group members demonstrated that they possessed the essential characteristics of commitment,
motivation and determination, in addition to the willingness and ability to use existing skills and knowledge effectively and to develop further skills and knowledge as the project proceeded. Perhaps most important, they developed a caring and effective working culture. However, the weaknesses of the project included a lack of preparation and planning prior to the commencement of the project which resulted in a build up of work at a number of stages. This, in turn, lead to delays in producing outcomes and some loss of momentum. It also led, indirectly, to the views of two or three members of the core group being overrepresented in the reo plan goals. The information and analysis provided here
have relevance to any language community involved in micro-level language regeneration activities of a similar type. It is hoped therefore that this thesis may help others to not only avoid the problems experienced by the Whakamārama whānau but also to benefit from their successes.

text: A criterion referenced analysis and evaluation of the processes involved in formulating a Māori language regeneration strategy for Whakamārama marae The quality of the processes involved in language regeneration strategy formation is critical to the creation of an effective language regeneration strategy and this, in turn, is critical to the achievement of successful language regeneration outcomes. The overall aim of this research project was to evaluate, using a range of effectiveness criteria, the processes involved in the creation of a marae-based te reo Māori regeneration strategy in the hope that others involved in similar projects in the future would benefit and in the hope that the Whakamārama whānau will themselves derive benefit from it in reviewing what has already been achieved. In Chapter 1, the background to the research project and its rationale are outlined
and the research questions and research methods are introduced. Chapter 2 provides a critical review of selected literature in the area of strategic planning aspects of language regeneration and relevant aspects of mātauranga Māori. Using an ethnographic approach, the processes and immediate outcomes (in terms of a
survey report and a regeneration plan for Whakamārama marae) of the language regeneration project are outlined in Chapter 3. In Chapter 4, effectiveness criteria are derived on the basis of the literature review in Chapter 2. These include criteria relating to leadership, participation, Kaupapa Māori values, environmental
analysis and outcomes. The criteria are then applied to the analysis and evaluation of the processes and outcomes outlined in Chapter 3 in order to identify their strengths and weaknesses. The overall conclusion is that Whakamārama's
language regeneration activities to date can be regarded as successful in many ways, including the fact that they have resulted in the production of high quality documentation that is widely appreciated by the whānau in the form of a maraebased language survey and a marae-based te reo Māori regeneration plan. Working voluntarily and often under difficult circumstances, core group members demonstrated that they possessed the essential characteristics of commitment,
motivation and determination, in addition to the willingness and ability to use existing skills and knowledge effectively and to develop further skills and knowledge as the project proceeded. Perhaps most important, they developed a caring and effective working culture. However, the weaknesses of the project included a lack of preparation and planning prior to the commencement of the project which resulted in a build up of work at a number of stages. This, in turn, lead to delays in producing outcomes and some loss of momentum. It also led, indirectly, to the views of two or three members of the core group being overrepresented in the reo plan goals. The information and analysis provided here
have relevance to any language community involved in micro-level language regeneration activities of a similar type. It is hoped therefore that this thesis may help others to not only avoid the problems experienced by the Whakamārama whānau but also to benefit from their successes.

year: 2007