title: Environmentally Sustainable Aquaculture: An Eco-Physical Perspective

authors: Longdill, Peter C.

subjects: Bay of Plenty

abstract: The New Zealand aquaculture industry during the late 1990s and early 2000s experienced a significant and sustained period of growth.  Greenshell mussels (Perna canaliculus) are proving to be a popular and valuable cultured species, with large domestic and international markets.  Traditionally, these bivalves have been farmed within enclosed embayments and on relatively small scales (~3 Ha).  The recent expansion of the industry coupled with the near saturation of existing 'traditional' sites and new culture technologies has led the industry toward alternate environments, notably exposed offshore sites.  Initial proposals within the Bay of Plenty have included multiple farms of ~4500 Ha each.  This novel approach to shellfish culture created uncertainty with respect to potential environmental impacts, cumulative effects, and sustainable carrying capacities within these exposed open-coast locations.  In zoning for Aquaculture Management Areas (AMAs), environmental managers must be informed of each of these aspects to ensure the rational and sustainable use of the coastal-marine space.

The overall goal of this study is to determine the potential for environmentally sustainable large-scale offshore mussel culture within the Bay of Plenty marine environment.  The long term sustainability of aquaculture development on an open coast is a function of many influences which can vary in both time and space.  The benthic environments of the Bay of Plenty exhibit great variability in their ability to assimilate waste inputs from suspended mussel culture; a direct function of the variability in sedimentary environments and benthic habitats within the region.  Specifically, silty sediments with low natural organic contents, generally found between 40 and 100 m depths are the most suitable locations for sustainable mussel aquaculture from an environmental impact perspective.  Both observations and model predictions indicate productivity potential within the region to be greatest within neritic zones of the western Bay of Plenty.  Local wind forcing is the predominant mechanism forcing local shelf currents.  Current meter data and numerical modelling tests from this study indicate that local winds explain the majority of water current variability on the shelf, generate the delivery of new nutrients to the shelf through upwelling, and hence create the variability in productivity potential.  Complicating the AMA zoning process for environmental managers, however, are existing uses of, and societal values toward, the coastal-marine environment.  GIS planning tools have been shown to be effective at minimising conflicts and maximising sustainability potential through informed site selection.  Within the Bay of Plenty, these preferential sites are located on the mid-shelf (60-80 m depths) offshore from Pukehina, Matata, and Whakatane.  

This study shows that the simulated cumulative lower trophic-level depletion impacts of two large (~5000 Ha) proposed offshore mussel farms vary seasonally as a result of subtle changes in ecosystem dynamics and mussel feeding patterns.  At proposed stocking densities, largest relative impacts are expected during autumn and winter, when relative phytoplankton biomass is low and growth rates slow.  During spring, while absolute impacts are greater than those during autumn/winter, greater phytoplankton-zooplankton biomass and faster growth rates result in quicker recovery times and reduced 'depletion halo' extents.  Year-long predicted impacts are below those applied as 'acceptable limits of change', both within New Zealand and internationally, indicative of the ecological carrying capacity.

text: Environmentally Sustainable Aquaculture: An Eco-Physical Perspective The New Zealand aquaculture industry during the late 1990s and early 2000s experienced a significant and sustained period of growth.  Greenshell mussels (Perna canaliculus) are proving to be a popular and valuable cultured species, with large domestic and international markets.  Traditionally, these bivalves have been farmed within enclosed embayments and on relatively small scales (~3 Ha).  The recent expansion of the industry coupled with the near saturation of existing 'traditional' sites and new culture technologies has led the industry toward alternate environments, notably exposed offshore sites.  Initial proposals within the Bay of Plenty have included multiple farms of ~4500 Ha each.  This novel approach to shellfish culture created uncertainty with respect to potential environmental impacts, cumulative effects, and sustainable carrying capacities within these exposed open-coast locations.  In zoning for Aquaculture Management Areas (AMAs), environmental managers must be informed of each of these aspects to ensure the rational and sustainable use of the coastal-marine space.

The overall goal of this study is to determine the potential for environmentally sustainable large-scale offshore mussel culture within the Bay of Plenty marine environment.  The long term sustainability of aquaculture development on an open coast is a function of many influences which can vary in both time and space.  The benthic environments of the Bay of Plenty exhibit great variability in their ability to assimilate waste inputs from suspended mussel culture; a direct function of the variability in sedimentary environments and benthic habitats within the region.  Specifically, silty sediments with low natural organic contents, generally found between 40 and 100 m depths are the most suitable locations for sustainable mussel aquaculture from an environmental impact perspective.  Both observations and model predictions indicate productivity potential within the region to be greatest within neritic zones of the western Bay of Plenty.  Local wind forcing is the predominant mechanism forcing local shelf currents.  Current meter data and numerical modelling tests from this study indicate that local winds explain the majority of water current variability on the shelf, generate the delivery of new nutrients to the shelf through upwelling, and hence create the variability in productivity potential.  Complicating the AMA zoning process for environmental managers, however, are existing uses of, and societal values toward, the coastal-marine environment.  GIS planning tools have been shown to be effective at minimising conflicts and maximising sustainability potential through informed site selection.  Within the Bay of Plenty, these preferential sites are located on the mid-shelf (60-80 m depths) offshore from Pukehina, Matata, and Whakatane.  

This study shows that the simulated cumulative lower trophic-level depletion impacts of two large (~5000 Ha) proposed offshore mussel farms vary seasonally as a result of subtle changes in ecosystem dynamics and mussel feeding patterns.  At proposed stocking densities, largest relative impacts are expected during autumn and winter, when relative phytoplankton biomass is low and growth rates slow.  During spring, while absolute impacts are greater than those during autumn/winter, greater phytoplankton-zooplankton biomass and faster growth rates result in quicker recovery times and reduced 'depletion halo' extents.  Year-long predicted impacts are below those applied as 'acceptable limits of change', both within New Zealand and internationally, indicative of the ecological carrying capacity.

year: 2008

title: Visiting friends and relatives (VFR) in the Bay of Plenty

authors: Cave, Jennifer Barbara Jane

abstract: Tourism Bay of Plenty is interested to know whether local hosts of visiting friends and relatives (VFR) might be encouraged to play a larger part in the tourism economy of the Bay.
This survey of 699 individuals gives a 4-week snapshot of VFR activity in the Bay of Plenty in summer 2016 including Auckland Anniversary and Waitangi Days; and a week at Easter during the Tauranga Jazz Festival.
Issues investigated are: VFR profile, social dynamics which affect participation; activity patterns; the image of the Bay of Plenty; destination management issues that affect image; and the impact that VFR have on the visitor economy.

text: Visiting friends and relatives (VFR) in the Bay of Plenty Tourism Bay of Plenty is interested to know whether local hosts of visiting friends and relatives (VFR) might be encouraged to play a larger part in the tourism economy of the Bay.
This survey of 699 individuals gives a 4-week snapshot of VFR activity in the Bay of Plenty in summer 2016 including Auckland Anniversary and Waitangi Days; and a week at Easter during the Tauranga Jazz Festival.
Issues investigated are: VFR profile, social dynamics which affect participation; activity patterns; the image of the Bay of Plenty; destination management issues that affect image; and the impact that VFR have on the visitor economy.

year: 2016

title: Composition Portfolio

authors: Ulenberg, Phillippa

subjects: composition portfolio

abstract: The music written for this portfolio offers creative answers to some of the challenges facing contemporary New Zealand composition, including multiculturalism.This has involved in-depth research using a variety of methods. Engagement was undertaken with linguists and musicians from Malaysia and Korea, who not only assisted with texts, but also spoke knowledgeably about their cultural traditions and past and present musical genres. The inclusion of Chinese gu-zheng in several of the works was made possible with the assistance given by Chen Xi Yao, an excellent performer who comes from a long lineage of musicians. Attending concerts given by performers of the instruments that have been used in the portfolio was essential to understanding the sounds and uses of the instruments. In addition, on-line sources include many examples of the sounds. Attendance at workshops on Māori taonga pūoro also brought the additional honour, benefits and experience of making and playing the instruments, and the opportunities to meet and work with leading makers and performers of these musical treasures. Sources of Western classical music that have been particularly influential during the writing of the portfolio are orchestral works by Igor Stravinsky, Samuel Barber and Param Vir, and the song cycles of Alban Berg and Benjamin Britten. Luciano Berio’s virtuosic piece for solo bassoon was also instructive. Experiences of composition, reflection and scholarly research underpin the portfolio and have have informed the composition of each work.

text: Composition Portfolio The music written for this portfolio offers creative answers to some of the challenges facing contemporary New Zealand composition, including multiculturalism.This has involved in-depth research using a variety of methods. Engagement was undertaken with linguists and musicians from Malaysia and Korea, who not only assisted with texts, but also spoke knowledgeably about their cultural traditions and past and present musical genres. The inclusion of Chinese gu-zheng in several of the works was made possible with the assistance given by Chen Xi Yao, an excellent performer who comes from a long lineage of musicians. Attending concerts given by performers of the instruments that have been used in the portfolio was essential to understanding the sounds and uses of the instruments. In addition, on-line sources include many examples of the sounds. Attendance at workshops on Māori taonga pūoro also brought the additional honour, benefits and experience of making and playing the instruments, and the opportunities to meet and work with leading makers and performers of these musical treasures. Sources of Western classical music that have been particularly influential during the writing of the portfolio are orchestral works by Igor Stravinsky, Samuel Barber and Param Vir, and the song cycles of Alban Berg and Benjamin Britten. Luciano Berio’s virtuosic piece for solo bassoon was also instructive. Experiences of composition, reflection and scholarly research underpin the portfolio and have have informed the composition of each work.

year: 2011