title: Assessment of injury to New Zealand native fish by boat electrofishing

authors: de Villiers, Joshua

subjects: Electrofishing

abstract: This study investigated the survival, incidence and severity of injuries and physiological reactions to stress caused by boat electrofishing in comparison with standard netting techniques in three New Zealand native fish species. Shortfin eel (Anguilla australis), grey mullet (Mugil cephalus) and common smelt (Retropinna retropinna) were captured from the Waikato River and its surrounding lakes with standardised boat electrofishing techniques (60-Hz pulsed direct current, 45-60% of range with the 0-500-V peak voltage machine setting, 3-4 Amps root mean square output). Fish were captured in water of 133-154 μScm─1 ambient conductivity at 18-21oC. Capture techniques used for comparison were fyke netting for eels, gill netting for grey mullet and beach seine netting for smelt.
Survival was assessed in eels that held for 30 days after capture and smelt that were held for 30 min after capture. Several different methods were used to assess the incidence and severity of injuries. External examinations were used to assess branding and abrasions, and internal injuries were assessed by radiographic imaging and bilateral filleting to reveal haemorrhaging and spinal damage. Finally, physiological stress was determined by an analysis of haematocrit and haemoglobin concentration and an analysis of blood plasma ions (sodium, potassium, magnesium and calcium).
Survival over 30 days of shortfin eels captured by electrofishing (92% for Lake Areare eels and 96% for Lake Rotongaro eels) was similar to that for fyke netting (92% for Lake Areare and 88% for Lake Rotongaro). Two eels appeared to have died from fungal infections as no haemorrhaging or spinal injuries were apparent among the mortalities. External examinations revealed that no abrasions or branding occurred in eels captured by electrofishing; however, abrasions occurred in eels captured by fyke netting (24% for Lake Areare eels and 16% for Lake Rotongaro eels).
Rates of internal haemorrhaging immediately after electrofishing were inconsistent (0% in Lake Areare and 28% in Lake Rotongaro); in Lake Rotongaro, this was significantly greater than those captured by fyke netting, in which only 8% had haemorrhages. No haemorrhaging was observed in eels after 30 days from Lake Areare. Haemorrhages from electrofishing in our study appeared to heal within the 30-day holding period, as the incidence of haemorrhaging in Rotongaro eels reduced from 28% at capture to only 4% after 30 days in captivity. Rates of spinal injury in eels captured by electrofishing was also variable (12% in Lake Areare eels and 8% in Lake Rotongaro eels), compared to the rate of spinal injury in eels captured by fyke netting (0% in Lake Areare eels and 4% in Lake Rotongaro eels). The upper rate of haemorrhaging that we found for electrofishing in shortfin eels (28%) was similar to injury rates for electrofished American eels (25%), but our rates of spinal damage (8-12%) were much lower than for American eels (60%).
In grey mullet, there was no significant difference (P > 0.101) in the occurrence of haemorrhages or spinal injuries between the two capture methods. However, physiological stress from electrofishing caused a significantly (t = 2.37, P = 0.02) reduced sodium ion concentration (139.38 ± 13.24 mM) compared to that of gill netting (149.06 ± 15.58 mM). Electrofishing also caused a significantly (t = 4.61, P < 0.001) lower concentration of haemoglobin (86.55 ± 9.21 g L-1) compared to that of grey mullet captured by gill netting (108.81 ± 23.86 g L-1). However, there were no significant differences between capture methods for the other blood plasma constituents tested (haematocrit and the blood plasma ions sodium, potassium, magnesium and calcium).
Survival was high in smelt captured by both electrofishing (94.8%, n = 1217) and by seine netting (92.9%, n = 1271), with no statistically significant difference between the two fishing methods (t = −1.021, P = 0.320). In a subsample of smelt analysed for injuries (n = 40 for each method), external injuries were observed in 15% (n = 6) of smelt captured by electrofishing and in 20% (n = 8) of smelt captured by seine netting. No haemorrhages were detected in smelt for either of the capture methods and there was no significant difference (G = 0.215, P = 0.642) in the rate of spinal injuries in smelt captured by electrofishing (10%, n = 4) or by seine netting (5%, n = 2).
These results suggest that boat electrofishing as practiced in New Zealand is in the long term generally no more harmful to shortfin eels, grey mullet, and common smelt than other comparable capture sampling techniques. Exceptions to this
conclusion were increased haemorrhaging in electrofished shortfin eels, from which they recovered within 30 days, and reduced sodium and haemoglobin concentrations in electrofished grey mullet, which are signs of physiological stress. All fishing methods examined caused some level of injury, stress, or mortality in the three species studied. Netting techniques (fyke net, gill netting, and seine netting) that are commonly used will also cause harm and these techniques are currently used far more widely than boat electrofishing.

text: Assessment of injury to New Zealand native fish by boat electrofishing This study investigated the survival, incidence and severity of injuries and physiological reactions to stress caused by boat electrofishing in comparison with standard netting techniques in three New Zealand native fish species. Shortfin eel (Anguilla australis), grey mullet (Mugil cephalus) and common smelt (Retropinna retropinna) were captured from the Waikato River and its surrounding lakes with standardised boat electrofishing techniques (60-Hz pulsed direct current, 45-60% of range with the 0-500-V peak voltage machine setting, 3-4 Amps root mean square output). Fish were captured in water of 133-154 μScm─1 ambient conductivity at 18-21oC. Capture techniques used for comparison were fyke netting for eels, gill netting for grey mullet and beach seine netting for smelt.
Survival was assessed in eels that held for 30 days after capture and smelt that were held for 30 min after capture. Several different methods were used to assess the incidence and severity of injuries. External examinations were used to assess branding and abrasions, and internal injuries were assessed by radiographic imaging and bilateral filleting to reveal haemorrhaging and spinal damage. Finally, physiological stress was determined by an analysis of haematocrit and haemoglobin concentration and an analysis of blood plasma ions (sodium, potassium, magnesium and calcium).
Survival over 30 days of shortfin eels captured by electrofishing (92% for Lake Areare eels and 96% for Lake Rotongaro eels) was similar to that for fyke netting (92% for Lake Areare and 88% for Lake Rotongaro). Two eels appeared to have died from fungal infections as no haemorrhaging or spinal injuries were apparent among the mortalities. External examinations revealed that no abrasions or branding occurred in eels captured by electrofishing; however, abrasions occurred in eels captured by fyke netting (24% for Lake Areare eels and 16% for Lake Rotongaro eels).
Rates of internal haemorrhaging immediately after electrofishing were inconsistent (0% in Lake Areare and 28% in Lake Rotongaro); in Lake Rotongaro, this was significantly greater than those captured by fyke netting, in which only 8% had haemorrhages. No haemorrhaging was observed in eels after 30 days from Lake Areare. Haemorrhages from electrofishing in our study appeared to heal within the 30-day holding period, as the incidence of haemorrhaging in Rotongaro eels reduced from 28% at capture to only 4% after 30 days in captivity. Rates of spinal injury in eels captured by electrofishing was also variable (12% in Lake Areare eels and 8% in Lake Rotongaro eels), compared to the rate of spinal injury in eels captured by fyke netting (0% in Lake Areare eels and 4% in Lake Rotongaro eels). The upper rate of haemorrhaging that we found for electrofishing in shortfin eels (28%) was similar to injury rates for electrofished American eels (25%), but our rates of spinal damage (8-12%) were much lower than for American eels (60%).
In grey mullet, there was no significant difference (P > 0.101) in the occurrence of haemorrhages or spinal injuries between the two capture methods. However, physiological stress from electrofishing caused a significantly (t = 2.37, P = 0.02) reduced sodium ion concentration (139.38 ± 13.24 mM) compared to that of gill netting (149.06 ± 15.58 mM). Electrofishing also caused a significantly (t = 4.61, P < 0.001) lower concentration of haemoglobin (86.55 ± 9.21 g L-1) compared to that of grey mullet captured by gill netting (108.81 ± 23.86 g L-1). However, there were no significant differences between capture methods for the other blood plasma constituents tested (haematocrit and the blood plasma ions sodium, potassium, magnesium and calcium).
Survival was high in smelt captured by both electrofishing (94.8%, n = 1217) and by seine netting (92.9%, n = 1271), with no statistically significant difference between the two fishing methods (t = −1.021, P = 0.320). In a subsample of smelt analysed for injuries (n = 40 for each method), external injuries were observed in 15% (n = 6) of smelt captured by electrofishing and in 20% (n = 8) of smelt captured by seine netting. No haemorrhages were detected in smelt for either of the capture methods and there was no significant difference (G = 0.215, P = 0.642) in the rate of spinal injuries in smelt captured by electrofishing (10%, n = 4) or by seine netting (5%, n = 2).
These results suggest that boat electrofishing as practiced in New Zealand is in the long term generally no more harmful to shortfin eels, grey mullet, and common smelt than other comparable capture sampling techniques. Exceptions to this
conclusion were increased haemorrhaging in electrofished shortfin eels, from which they recovered within 30 days, and reduced sodium and haemoglobin concentrations in electrofished grey mullet, which are signs of physiological stress. All fishing methods examined caused some level of injury, stress, or mortality in the three species studied. Netting techniques (fyke net, gill netting, and seine netting) that are commonly used will also cause harm and these techniques are currently used far more widely than boat electrofishing.

year: 2013

title: Vicarious learning in SME internationalization: A systematic review and thematic synthesis

authors: Perera, Shanika Rangani

subjects: vicarious learning

abstract: Vicarious learning helps small and medium-sized enterprises (SMEs) acquire foreign market knowledge by observing and interpreting other firms’ actions and outcomes in international markets. We searched Scopus, ProQuest, and EBSCOhost (2000–2025) and retained 27 studies (2007–2025). The synthesis organizes prior studies into four analytically derived categories that summarize how vicarious learning is conceptualized and operationalized in SME internationalization research: (T1) peer performance benchmarking, (T2) imitation and leader-following, (T3) institutional mimetic pressures, and (T4) network-, cluster-, and advisor-enabled vicarious learning. Across themes, a subset of studies suggests that absorptive capacity may condition whether external experience is recognized, assimilated, and exploited, although direct tests remain uneven and in some cases the contingency is inferred rather than explicitly tested. We translate these insights into an organizing framework and a future agenda on boundary conditions, measurement, and multi-level designs, positioning the review as mechanism clarification that imposes conceptual order on a fragmented literature, rather than as field-level consolidation.

text: Vicarious learning in SME internationalization: A systematic review and thematic synthesis Vicarious learning helps small and medium-sized enterprises (SMEs) acquire foreign market knowledge by observing and interpreting other firms’ actions and outcomes in international markets. We searched Scopus, ProQuest, and EBSCOhost (2000–2025) and retained 27 studies (2007–2025). The synthesis organizes prior studies into four analytically derived categories that summarize how vicarious learning is conceptualized and operationalized in SME internationalization research: (T1) peer performance benchmarking, (T2) imitation and leader-following, (T3) institutional mimetic pressures, and (T4) network-, cluster-, and advisor-enabled vicarious learning. Across themes, a subset of studies suggests that absorptive capacity may condition whether external experience is recognized, assimilated, and exploited, although direct tests remain uneven and in some cases the contingency is inferred rather than explicitly tested. We translate these insights into an organizing framework and a future agenda on boundary conditions, measurement, and multi-level designs, positioning the review as mechanism clarification that imposes conceptual order on a fragmented literature, rather than as field-level consolidation.

year: 2026

title: Kia matatau ki te reo: Factors influencing the development of proficiency in te reo Māori with adult learners

authors: Rātima, Matiu Tai

subjects: te reo Māori

abstract: This thesis sought to answer the question: what factors help or hinder adult Māori second language learners to become proficient speakers of te reo Māori? I ask this question at a moment in history when te reo, like other indigenous languages, sits on the edge of a precipice in terms of its survival as a living language. Ambivalence and inaction will almost certainly constitute a push towards oblivion. Nothing less than concerted effort can pull te reo back from the brink. But what kind of concerted effort is needed and how can individual learners optimise their efforts to learn te reo?
Te reo must survive because, as Sir James Henare put it, ‘ko te reo te hā o te Māoritanga’, meaning ‘the language is the essence of Māori culture.’ Without te reo the very survival of Māori people as Māori is in doubt. My questions and the thesis occupy a multidisciplinary space, drawing on research from adult second language acquisition, teaching pedagogy and language revitalisation. The thesis makes an original contribution to all three bodies of literature by examining data from a previously untapped source; successful adult Māori language learners. 
I interviewed 17 participants. All highly proficient second language speakers of te reo. All learned te reo as adults.  Adult second language learning of endangered languages is broadly acknowledged in Second Language Acquisition (SLA) as essential to re-establishing Intergenerational Transmission of Language (ITL) in the home to ensure an endangered language is passed on to future generations.
The interview questionnaire was based loosely on 10 help/hinder factors I identified through a review of the literature from the three research fields (adult second language acquisition, teaching pedagogy and language revitalisation). The ten factors identified in the review were; language aptitude, age, learner attitudes and motivation, learning strategies, instruction, agency and anxiety, wairua (the spiritual dimension), demography, language status, and language planning.

text: Kia matatau ki te reo: Factors influencing the development of proficiency in te reo Māori with adult learners This thesis sought to answer the question: what factors help or hinder adult Māori second language learners to become proficient speakers of te reo Māori? I ask this question at a moment in history when te reo, like other indigenous languages, sits on the edge of a precipice in terms of its survival as a living language. Ambivalence and inaction will almost certainly constitute a push towards oblivion. Nothing less than concerted effort can pull te reo back from the brink. But what kind of concerted effort is needed and how can individual learners optimise their efforts to learn te reo?
Te reo must survive because, as Sir James Henare put it, ‘ko te reo te hā o te Māoritanga’, meaning ‘the language is the essence of Māori culture.’ Without te reo the very survival of Māori people as Māori is in doubt. My questions and the thesis occupy a multidisciplinary space, drawing on research from adult second language acquisition, teaching pedagogy and language revitalisation. The thesis makes an original contribution to all three bodies of literature by examining data from a previously untapped source; successful adult Māori language learners. 
I interviewed 17 participants. All highly proficient second language speakers of te reo. All learned te reo as adults.  Adult second language learning of endangered languages is broadly acknowledged in Second Language Acquisition (SLA) as essential to re-establishing Intergenerational Transmission of Language (ITL) in the home to ensure an endangered language is passed on to future generations.
The interview questionnaire was based loosely on 10 help/hinder factors I identified through a review of the literature from the three research fields (adult second language acquisition, teaching pedagogy and language revitalisation). The ten factors identified in the review were; language aptitude, age, learner attitudes and motivation, learning strategies, instruction, agency and anxiety, wairua (the spiritual dimension), demography, language status, and language planning.

year: 2013