title: Consumption of submerged aquatic macrophytes by rudd (scardinius erythrophthalmus L.) in New Zealand

authors: Lake, Michael D.

subjects: aquatic macrophytes

abstract: In experiments in New Zealand, rudd (Scardinius erythrophthalmus L.) of 108–277mm fork length (FL) ate a wide range of native and introduced submerged aquatic macrophytes in captivity and in the field. Rudd consumed the native charophytes Chara globularis Thuill., Chara fibrosa Ag. ex Bruz., and Nitella spp., the native macrophytes Potamogeton ochreatus Raoul. and Myriophyllum propinquum A. Cunn., and the introduced macrophytes Elodea canadensis Michx., Egeria densa Planch., Lagarosiphon major L., and Ceratophyllum demersum L. Rudd consistently consumed the Nitella spp. and Potamogeton ochreatus before Ceratophyllum demersum. From the results of experiments in tanks and in the field, we found the order of highest to lowest palatability was: Nitella spp. > Potamogeton ochreatus > Elodea canadensis> Chara globularis = Chara fibrosa> Egeria densa = Lagarosiphon major > Myriophyllum propinquum > Ceratophyllum demersum. The order of consumption was subject to some variation with season, especially for Egeria densa, Lagarosiphon major, and Myriophyllum propinquum. Rudd
consumed up to 20% of their body weight per day of Egeria densa in spring, and 22% of their body weight per day of Nitella spp. in summer. Consumption rates were considerably lower in winter than in summer. The results of our field trial suggested that the order of consumption also applies in the field and that rudd are having a profound impact on vulnerable native aquatic plant communities in New Zealand. Nitella spp. and Potamogeton ochreatus are likely to be selectively eaten, and herbivory by rudd might prevent the re-establishment of these species in
restoration efforts.

text: Consumption of submerged aquatic macrophytes by rudd (scardinius erythrophthalmus L.) in New Zealand In experiments in New Zealand, rudd (Scardinius erythrophthalmus L.) of 108–277mm fork length (FL) ate a wide range of native and introduced submerged aquatic macrophytes in captivity and in the field. Rudd consumed the native charophytes Chara globularis Thuill., Chara fibrosa Ag. ex Bruz., and Nitella spp., the native macrophytes Potamogeton ochreatus Raoul. and Myriophyllum propinquum A. Cunn., and the introduced macrophytes Elodea canadensis Michx., Egeria densa Planch., Lagarosiphon major L., and Ceratophyllum demersum L. Rudd consistently consumed the Nitella spp. and Potamogeton ochreatus before Ceratophyllum demersum. From the results of experiments in tanks and in the field, we found the order of highest to lowest palatability was: Nitella spp. > Potamogeton ochreatus > Elodea canadensis> Chara globularis = Chara fibrosa> Egeria densa = Lagarosiphon major > Myriophyllum propinquum > Ceratophyllum demersum. The order of consumption was subject to some variation with season, especially for Egeria densa, Lagarosiphon major, and Myriophyllum propinquum. Rudd
consumed up to 20% of their body weight per day of Egeria densa in spring, and 22% of their body weight per day of Nitella spp. in summer. Consumption rates were considerably lower in winter than in summer. The results of our field trial suggested that the order of consumption also applies in the field and that rudd are having a profound impact on vulnerable native aquatic plant communities in New Zealand. Nitella spp. and Potamogeton ochreatus are likely to be selectively eaten, and herbivory by rudd might prevent the re-establishment of these species in
restoration efforts.

year: 2002

title: Violent and prosocial music: Evidence for the impact of lyrics and musical tone on aggressive thoughts, feelings, and behaviors

authors: Warburton, WA

subjects: aggression

abstract: Although there is a large research base on the psychological impacts of violent and prosocial visual media, there is little research addressing the impacts of violent and prosocial music, and which facets of the music have the greatest impact. Four experiments tested the impact of lyrics and/or musical tone on aggressive and prosocial behavior, and on underlying psychological processes, using purpose-built songs to avoid the effect of music-related confounds. In study one, where mildly aggressive, overtly aggressive and violent lyrics were compared to neutral lyrics, any level of lyrical aggression caused an increase in behavioral aggression, which plateaued for all three aggression conditions. Violent lyrics were better recalled than other lyrics one week later. In studies two-three no significant effects of lyrics, or of aggressive versus nonaggressive musical tone, were found on aggressive or prosocial behavior. In terms of internal states, violent lyrics increased hostility/hostile cognitions in all studies, and negatively impacted affective state in three studies. Prosocial lyrics decreased hostility/hostile cognitions in three studies, but always in tandem with another factor. Aggressive musical tone increased physiological arousal in two studies and increased negative affect in one. In study four those who listened to violent lyrics drove more aggressively on a simulated drive that included triggers for aggression. Overall, violent lyrics consistently elicited hostility/hostile cognitions and negative affect, but these did not always translate to aggressive behavior. Violent music seems more likely to elicit behavioral aggression when there are aggression triggers and a clear way to aggress. Implications are discussed.

text: Violent and prosocial music: Evidence for the impact of lyrics and musical tone on aggressive thoughts, feelings, and behaviors Although there is a large research base on the psychological impacts of violent and prosocial visual media, there is little research addressing the impacts of violent and prosocial music, and which facets of the music have the greatest impact. Four experiments tested the impact of lyrics and/or musical tone on aggressive and prosocial behavior, and on underlying psychological processes, using purpose-built songs to avoid the effect of music-related confounds. In study one, where mildly aggressive, overtly aggressive and violent lyrics were compared to neutral lyrics, any level of lyrical aggression caused an increase in behavioral aggression, which plateaued for all three aggression conditions. Violent lyrics were better recalled than other lyrics one week later. In studies two-three no significant effects of lyrics, or of aggressive versus nonaggressive musical tone, were found on aggressive or prosocial behavior. In terms of internal states, violent lyrics increased hostility/hostile cognitions in all studies, and negatively impacted affective state in three studies. Prosocial lyrics decreased hostility/hostile cognitions in three studies, but always in tandem with another factor. Aggressive musical tone increased physiological arousal in two studies and increased negative affect in one. In study four those who listened to violent lyrics drove more aggressively on a simulated drive that included triggers for aggression. Overall, violent lyrics consistently elicited hostility/hostile cognitions and negative affect, but these did not always translate to aggressive behavior. Violent music seems more likely to elicit behavioral aggression when there are aggression triggers and a clear way to aggress. Implications are discussed.

year: 2024

title: Indigenous Psychology in Aotearoa: Realising Māori Aspirations

authors: Levy, Michelle Patricia

subjects: Maori

abstract: Indigenous psychology in Aotearoa positions the aspirations of Māori as central.  The aim of this thesis is to describe and contribute to the development of a psychological discipline which is relevant and of benefit for Māori communities.  Part One sets the scene in Aotearoa, examining the relationship between Māori development and psychology.  Part Two explores the indigenous psychology literature base, identifying strategies which may be relevant to Aotearoa.  The key themes of context, critical mass, and mechanisms to support indigenous psychology development are identified as being relevant to Aotearoa.  Part Three explores indigenous psychology development in Aotearoa.  Data from a range of sources is qualitatively analysed to develop five themes which describe the current status of Māori development in psychology, the importance of the critical mass and the notion of collective responsibility.  Part Four, drawing from the analysis in Parts One, Two and Three, identifies 'reaching the point of irreversible change' as the next phase of indigenous psychology development in Aotearoa.  This is the point at which indigenous psychology development becomes self-sustaining.  

The point at which irreversible change occurs is when: Māori knowledge bases are a legitimate part of psychology in Aotearoa; resistance to the legitimacy of Māori knowledge bases in psychology is not a characteristic of our landscape; environments supportive of indigenous psychology development are commonplace; and responsibility for contributing to indigenous psychology development is shared among and sustained by the collective capacity of the Leaders and Producers.  Consolidation, the process by which multiple and interrelated pathways are connected to form a unified whole, is fundamental to reaching the point of irreversible change.  An original interactional framework for consolidation is proposed.  This framework is based on two key consolidating mechanisms: a working description of Kaupapa Māori Psychologies; and a Kaupapa Māori Psychologies Research and Training Centre.  Psychologies relevant and of benefit to Māori communities which contribute to the realisation of Māori aspirations are the cornerstones, with all elements of the framework leading back into this fundamental foundation.

text: Indigenous Psychology in Aotearoa: Realising Māori Aspirations Indigenous psychology in Aotearoa positions the aspirations of Māori as central.  The aim of this thesis is to describe and contribute to the development of a psychological discipline which is relevant and of benefit for Māori communities.  Part One sets the scene in Aotearoa, examining the relationship between Māori development and psychology.  Part Two explores the indigenous psychology literature base, identifying strategies which may be relevant to Aotearoa.  The key themes of context, critical mass, and mechanisms to support indigenous psychology development are identified as being relevant to Aotearoa.  Part Three explores indigenous psychology development in Aotearoa.  Data from a range of sources is qualitatively analysed to develop five themes which describe the current status of Māori development in psychology, the importance of the critical mass and the notion of collective responsibility.  Part Four, drawing from the analysis in Parts One, Two and Three, identifies 'reaching the point of irreversible change' as the next phase of indigenous psychology development in Aotearoa.  This is the point at which indigenous psychology development becomes self-sustaining.  

The point at which irreversible change occurs is when: Māori knowledge bases are a legitimate part of psychology in Aotearoa; resistance to the legitimacy of Māori knowledge bases in psychology is not a characteristic of our landscape; environments supportive of indigenous psychology development are commonplace; and responsibility for contributing to indigenous psychology development is shared among and sustained by the collective capacity of the Leaders and Producers.  Consolidation, the process by which multiple and interrelated pathways are connected to form a unified whole, is fundamental to reaching the point of irreversible change.  An original interactional framework for consolidation is proposed.  This framework is based on two key consolidating mechanisms: a working description of Kaupapa Māori Psychologies; and a Kaupapa Māori Psychologies Research and Training Centre.  Psychologies relevant and of benefit to Māori communities which contribute to the realisation of Māori aspirations are the cornerstones, with all elements of the framework leading back into this fundamental foundation.

year: 2007