title: Investigating the socio-economic impacts of the introduced Asian paddle crab, Charybdis japonica, on New Zealand’s native paddle crab fishery

authors: Weaver, Shannon Jaine

subjects: Invasive species

abstract: Despite the body of scientific research that exists on Charybdis japonica since it’s discovery in New Zealand in 2000, an investigation into the socio-economic impacts this introduced species may have was lacking. This study focuses on the potential socio-economic impacts from C. japonica on NZ’s native paddle crab (Ovalipes catharus) fishery. Charybdis japonica has spread steadily throughout the North Island of NZ, predominantly in an area that coincides with the main commercial fishing area for O. catharus (federally managed and defined as ‘PAD1’). Fishers perceptions of change and impacts in the fishery were investigated across the commercial and recreational sectors within this focus area. Qualitative, semi-structured interviews with commercial crab fishers covered three main areas: (1) background information on the O. catharus fishery, (2) perceptions of change in the fishery, (3) knowledge of C. japonica and perceived impact. Surveys with recreational fishers also covered these areas, with additional questions on their perceptions of the value of certain coastal environmental aspects (i.e., safety, cleanliness, biodiversity). 

Commercial fisheries catch data for the five main O. catharus fishing regions was also analysed to assess if a significant change in catch rates pre- and post- the arrival of C. japonica in NZ had occurred. Results showed significant changes in PAD1, PAD7 and PAD8 fisheries management areas. Given C. japonica has not yet been found in PAD7 and PAD8, catch rate changes within these three areas are likely due to other unmeasured variables. Commercial fishers predominantly suggested C. japonica had not yet had an observable impact on the O. catharus fishery. Recreational fishers that participated in this study had only had a short-term exposure to the fishery (the majority had started fishing for crabs less than a year ago), thus they had limited perceptions of change within the fishery. Commercial and recreational fishers were also tested on their ability to accurately identify the two crab species. Both sectors accurately identified O. catharus 95% of the time and C. japonica 55% of the time from a series of four images, with no statistically significant difference in accuracy between the two sectors. 
Despite some evidence of self-reported awareness of C. japonica in this study, further sustained public education to enable identification of this introduced species is needed if the public are to be incorporated into the management of this species. Commercial fishers highlighted the potential impact C. japonica may have on the flatfish fishery, an area requiring further investigation. Further research on the impacts C. japonica could have on other species of ecological, social, cultural and economic importance in NZ is required.

text: Investigating the socio-economic impacts of the introduced Asian paddle crab, Charybdis japonica, on New Zealand’s native paddle crab fishery Despite the body of scientific research that exists on Charybdis japonica since it’s discovery in New Zealand in 2000, an investigation into the socio-economic impacts this introduced species may have was lacking. This study focuses on the potential socio-economic impacts from C. japonica on NZ’s native paddle crab (Ovalipes catharus) fishery. Charybdis japonica has spread steadily throughout the North Island of NZ, predominantly in an area that coincides with the main commercial fishing area for O. catharus (federally managed and defined as ‘PAD1’). Fishers perceptions of change and impacts in the fishery were investigated across the commercial and recreational sectors within this focus area. Qualitative, semi-structured interviews with commercial crab fishers covered three main areas: (1) background information on the O. catharus fishery, (2) perceptions of change in the fishery, (3) knowledge of C. japonica and perceived impact. Surveys with recreational fishers also covered these areas, with additional questions on their perceptions of the value of certain coastal environmental aspects (i.e., safety, cleanliness, biodiversity). 

Commercial fisheries catch data for the five main O. catharus fishing regions was also analysed to assess if a significant change in catch rates pre- and post- the arrival of C. japonica in NZ had occurred. Results showed significant changes in PAD1, PAD7 and PAD8 fisheries management areas. Given C. japonica has not yet been found in PAD7 and PAD8, catch rate changes within these three areas are likely due to other unmeasured variables. Commercial fishers predominantly suggested C. japonica had not yet had an observable impact on the O. catharus fishery. Recreational fishers that participated in this study had only had a short-term exposure to the fishery (the majority had started fishing for crabs less than a year ago), thus they had limited perceptions of change within the fishery. Commercial and recreational fishers were also tested on their ability to accurately identify the two crab species. Both sectors accurately identified O. catharus 95% of the time and C. japonica 55% of the time from a series of four images, with no statistically significant difference in accuracy between the two sectors. 
Despite some evidence of self-reported awareness of C. japonica in this study, further sustained public education to enable identification of this introduced species is needed if the public are to be incorporated into the management of this species. Commercial fishers highlighted the potential impact C. japonica may have on the flatfish fishery, an area requiring further investigation. Further research on the impacts C. japonica could have on other species of ecological, social, cultural and economic importance in NZ is required.

year: 2017

title: Thawing permafrost alters nematode populations and soil habitat characteristics in an Antarctic polar desert ecosystem

authors: Smith, T. E.

subjects: cold desert

abstract: Spatial distribution of soil nematode populations in Antarctic terrestrial ecosystems is tightly controlled by environmental factors and thus highly sensitive to changes in soil properties. Increases in the magnitude and frequency of episodic warming events as well as eventual warming trends are likely to result in increased water availability due to glacial melting and permafrost thaw, and may also incite changes in soil physical and chemical characteristics that determine nematode habitat suitability. We hypothesized that climate warming would result in new suitable soil habitats leading to heightened diversity and activity in nematode communities. In order to test this hypothesis, we compared nematode populations in patches of soil wetted by naturally enhanced permafrost thaw versus adjacent soils unaffected by thaw. We found that thaw sites had significantly lower nematode abundances and living to dead ratios, contradicting our hypothesis. We also observed significantly altered soil texture (finer particle size), lower pH and higher salinity in permafrost seeps. These observations suggest that current and future changes in climate may alter soil properties and result in significant changes in nematode population structure, distribution and function.

text: Thawing permafrost alters nematode populations and soil habitat characteristics in an Antarctic polar desert ecosystem Spatial distribution of soil nematode populations in Antarctic terrestrial ecosystems is tightly controlled by environmental factors and thus highly sensitive to changes in soil properties. Increases in the magnitude and frequency of episodic warming events as well as eventual warming trends are likely to result in increased water availability due to glacial melting and permafrost thaw, and may also incite changes in soil physical and chemical characteristics that determine nematode habitat suitability. We hypothesized that climate warming would result in new suitable soil habitats leading to heightened diversity and activity in nematode communities. In order to test this hypothesis, we compared nematode populations in patches of soil wetted by naturally enhanced permafrost thaw versus adjacent soils unaffected by thaw. We found that thaw sites had significantly lower nematode abundances and living to dead ratios, contradicting our hypothesis. We also observed significantly altered soil texture (finer particle size), lower pH and higher salinity in permafrost seeps. These observations suggest that current and future changes in climate may alter soil properties and result in significant changes in nematode population structure, distribution and function.

year: 2012

title: Te Ika Huirua o Te Mate

authors: Maxwell, Te Kahautu

abstract: This composition is a lament to two staesman of the Māori world Apira Mahuika of Ngāti Porou and Tama Huata of Ngāti Kahungunu. Both men were giants in their respective areas, governance, tribal politics cultral revival language revitalisation, Treaty settlements they both died within days of each other. This compostion also talks about how Pākeha law clashes with Māori lore with the James Takamore case where his whanau took his body and returned it to James ancestral home Whakatohea and the widow laid charges to have her husbands remains dug up and returned to Christchuch. I thought it appropriate to protest about this being the Te Matatini World Championship Kapa Haka Competition was held in Christchurch March 2015. This composition was performed by Ōpōtiki Mai Tawhiti.

text: Te Ika Huirua o Te Mate This composition is a lament to two staesman of the Māori world Apira Mahuika of Ngāti Porou and Tama Huata of Ngāti Kahungunu. Both men were giants in their respective areas, governance, tribal politics cultral revival language revitalisation, Treaty settlements they both died within days of each other. This compostion also talks about how Pākeha law clashes with Māori lore with the James Takamore case where his whanau took his body and returned it to James ancestral home Whakatohea and the widow laid charges to have her husbands remains dug up and returned to Christchuch. I thought it appropriate to protest about this being the Te Matatini World Championship Kapa Haka Competition was held in Christchurch March 2015. This composition was performed by Ōpōtiki Mai Tawhiti.

year: 2015-02-12