25 research outputs found
Kōura (Paranephrops planifrons) populations in the Te Arawa lakes: An ecological assessment using the traditional Māori tau kōura harvesting method and recommendations for sustainable management
Freshwater crayfish are amongst the most influential of biota in many aquatic systems. They have various ecological functions, acting as shredders, detritivores and predators which in turn influence other macroinvertebrate fauna. Furthermore, freshwater crayfish are increasingly used as indicator species because of the important role they play in aquatic ecosystems and their iconic and heritage values. Kōura or freshwater crayfish (Paranephrops planifrons White) are endemic to New Zealand where they are an important component of freshwater ecosystems and a source of food for freshwater fish and humans. This study was undertaken to gain a better understanding of kōura populations in the Te Arawa lakes by quantifying relative kōura abundance and distribution and assessing the effects of environmental factors on kōura populations. In addition, basic biological information on sex ratios, breeding and moulting was collected as a basis for setting regulations and management policies for the sustainable management of kōura in the Te Arawa lakes.
Historically, kōura were an important food for the indigenous Māori people, particularly in the central North Island (CNI) lakes where large numbers were harvested for consumption and trading. Today, kōura are considered a ‘taonga’ species and support important customary fisheries in some CNI lakes (Rotomā, Rotoiti, Tarawera, and Taupō) where large populations of kōura still exist. Nevertheless, there is considerable anecdotal evidence of declines in populations of kōura in the Te Arawa lakes district since European settlement. A number of environmental factors have been implicated in this decline, including introductions of exotic fish and plant species as well as reduced concentrations of dissolved oxygen in the bottom waters of lakes due to eutrophication.
Although the ecology of stream-dwelling P. planifrons is well studied in New Zealand, there is limited published biological information on kōura in lakes. The lack of quantitative information on kōura abundance and ecology makes it difficult for iwi (Māori tribes) and government agencies to manage lake dwelling kōura populations. Until recently the main reason for the lack of quantitative information on lake kōura was the absence of suitable representative sampling methods. In a preliminary study of kōura sampling methods in the Te Arawa lakes, it was found that conventional sampling methods, baited traps, SCUBA and underwater video camera surveys had a number of disadvantages. Trapping was found to be highly biased towards large individuals and complicated by reductions in bait quality with time and changes in natural food abundance. SCUBA and underwater video camera surveys are also biased towards large individuals and are strongly dependent on underwater visibility. Given the disadvantages of these conventional kōura assessment methods, a traditional Māori harvesting method, the tau kōura, was adapted for the monitoring of lake kōura populations. The tau kōura captured large numbers and a wide size range (6 – 50 mm Orbit Carapace Length, OCL) of kōura in both shallow (5 m mean depth) and moderately deep water (10 – 17 m depth) in Ōkere Arm and Te Ākau, Lake Rotoiti, respectively. This method also distinguished differences in size structure and biomass between sites and provided information on sex ratios, egg-bearing and moulting. The development of the tau kōura thus enabled research and monitoring of lake kōura populations that may have not previously been representatively sampled and have generally been little studied in New Zealand despite their ecological and cultural significance.
The tau kōura was used to examine population dynamics of kōura, along a eutrophication gradient in seven Te Arawa lakes, in April, July and November 2009. Mean catch per unit effort (CPUE) and depth distribution of kōura were influenced by the combined effects of lake bed sediments, lake morphology, and hypolimnetic conditions related to trophic state. Although limited by the number of lakes that I was able to characterise, my data indicates that lake bed substrate (median sediment particle size) had a stronger influence on population characteristics than the level of enrichment/primary production as indexed by chlorophyll a (Chl-a). Nevertheless, the negative correlations between kōura abundance, with sediment carbon to nitrogen ratio (C/N), and the positive correlation between abundance and Chl-a, suggest that lake productivity does influence kōura. This component of the study indicates that eutrophication has reduced available kōura habitat in the Te Arawa lakes, particularly those that are sheltered, steep-sided and have fine lake bed sediments (with the Rotomahana mud tephra being particularly important). Lake bed substrate composition represented by sediment particle size is therefore a key factor to consider when selecting tau kōura sites for research, monitoring, restoration and harvesting, and when estimating kōura stocks in lakes. I concluded that measures to improve water quality in the Te Arawa lakes should benefit kōura populations by increasing the amount of oxygenated habitat available in the summer and autumn.
Kōura support important customary fisheries for iwi in some Te Arawa lakes, particularly Rotoiti, Rotomā and Tarawera. However, until recently, there was limited published biological information to provide a basis for fisheries regulations. This knowledge gap has resulted in the adoption of conservative fisheries regulations and management policies by the fishery managers, the Te Arawa Lakes Trust (TALT) and Ministry of Primary Industries (MPI). A further objective of the research was therefore to examine the biological traits of lake kōura and to consider implications of these traits on the current fishing regulations and sustainable management of kōura populations in the Te Arawa lakes.
From a review of past literature and the research findings from this study, it can be concluded that kōura populations in the Te Arawa lakes are currently not over-exploited due mostly to a low number participating in harvesting (almost exclusively Te Arawa) and because commercial harvesting is prohibited. However, the TALT wishes to encourage the revitalisation of traditional fishing practices (e.g., tau kōura) while adhering to the principles of kaitiakitanga ‒ the sustainable protection of resources. The establishment of sustainable management policies and regulations adheres to the principles of kaitiakitanga.
A number of management changes arising from the information collected in this study are suggested to protect and enhance the kōura fishery in the future. These are (1) set a slot limit with minimum size limit of 28 mm OCL and a maximum size limit of 39 mm OCL, (2) prohibit the taking of egg-bearing females, (3) limit deep-water harvest methods to the use of the tau kōura, and (4) implementing a tau kōura harvest season beginning on 1 December and ending on 31 March. These measures will protect breeding females if they are captured and the closed season will allow the majority of females to breed and release their young prior to fishing activity. Improving water quality (and thus increasing available kōura habitat) and preventing the introduction of predatory fish species such as eels (Anguilla spp.), catfish (Ameiurus nebulosus), and perch (Perca fluviatilis), that are efficient predators of kōura, are of the utmost importance in ensuring the sustainability of kōura populations in the Te Arawa lakes
M\=aori algorithmic sovereignty: idea, principles, and use
Due to the emergence of data-driven technologies in Aotearoa New Zealand that
use M\=aori data, there is a need for values-based frameworks to guide thinking
around balancing the tension between the opportunities these create, and the
inherent risks that these technologies can impose. Algorithms can be framed as
a particular use of data, therefore data frameworks that currently exist can be
extended to include algorithms. M\=aori data sovereignty principles are
well-known and are used by researchers and government agencies to guide the
culturally appropriate use of M\=aori data. Extending these principles to fit
the context of algorithms, and re-working the underlying sub-principles to
address issues related to responsible algorithms from a M\=aori perspective
leads to the M\=aori algorithmic sovereignty principles. We define this idea,
present the updated principles and subprinciples, and highlight how these can
be used to decolonise algorithms currently in use, and argue that these ideas
could potentially be used to developed Indigenised algorithms
Benefit sharing: Why inclusive provenance metadata matter
Fair and equitable benefit sharing of genetic resources is an expectation of the Nagoya Protocol. Although the Nagoya Protocol does not yet formally apply to Digital Sequence Information (“DSI”), discussions are currently underway regarding to include such data through ongoing Convention on Biological Diversity (“CBD”) negotiations. While Indigenous Peoples and Local Communities (“IPLC”) expect the value generated from genomic data to be subject to benefit sharing arrangements, a range of views are currently being expressed by Nation States, IPLC and other stakeholders. The use of DSI gives rise to unique considerations, creating a gray area as to how it should be considered under the Nagoya Protocol’s Access and Benefit Sharing (“ABS”) principles. One way for benefit sharing to be enhanced is through the connection of data to proper provenance information. A significant development is the use of digital labeling systems to ensure that the origin of samples is appropriately disclosed. The Traditional Knowledge and Biocultural Labels initiative offers a practical option for data provided to genomic databases. In particular, the BioCultural Labels (“BC Labels”) are a mechanism for Indigenous communities to identify and maintain provenance, origin and authority over biocultural material and data generated from Indigenous land and waters held in research, cultural institutions and data repositories. This form of cultural metadata adds value to the research endeavor and the creation of Indigenous fields within databases adds transparency and accountability to the research environment
Earthquake Mitigation Solutions for Collections - Experience from New Zealand’s National Museum
The Museum of New Zealand Te Papa Tongarewa, on the Wellington waterfront, has been developing its earthquake resilience since it was first built. The reclaimed land was compacted before building started and the building was built on base isolators (steel, rubber and lead shock absorbers) which help the building move with earthquakes, dissipating energy. Since building completion, there has been a steady implementation of earthquake mitigation systems.
Since 2010, New Zealand has experienced a series of strong earthquakes - Christchurch (2010-2011), Seddon (2013), and Kaikoura (2016). These sequences have instilled a perception that we are experiencing an extremely active geological period in New Zealand. And the last two events, in 2013 and 2016, had the greatest impact on the Wellington urban area. But earthquakes in New Zealand are constant. These more noticable events act as a test of earthquake resilience and motivate custodians to review current systems.
The first wave of most recent Te Papa investment to improve earthquake resilience occurred during 2012, after the Christchurch earthquakes. Since then, there has been a continuation of more focused solutions throughout Te Papa collection stores. A range of mitigation solutions were found for various containers and objects. We bolted, strapped, fastened and netted our way towards better collection storage. Practices around earthquake mitigation became part of our everyday collection management culture.
The work has been a collaboration between collection staff in order to discover the most creative and workable solutions, and these were transferred across collection areas. We will showcase some of our solutions, the elegant and not so elegant, and discuss lessons learnt
Earthquake Mitigation Solutions for Collections - Experience from New Zealand’s National Museum
The Museum of New Zealand Te Papa Tongarewa, on the Wellington waterfront, has been developing its earthquake resilience since it was first built. The reclaimed land was compacted before building started and the building was built on base isolators (steel, rubber and lead shock absorbers) which help the building move with earthquakes, dissipating energy. Since building completion, there has been a steady implementation of earthquake mitigation systems.
Since 2010, New Zealand has experienced a series of strong earthquakes - Christchurch (2010-2011), Seddon (2013), and Kaikoura (2016). These sequences have instilled a perception that we are experiencing an extremely active geological period in New Zealand. And the last two events, in 2013 and 2016, had the greatest impact on the Wellington urban area. But earthquakes in New Zealand are constant. These more noticable events act as a test of earthquake resilience and motivate custodians to review current systems.
The first wave of most recent Te Papa investment to improve earthquake resilience occurred during 2012, after the Christchurch earthquakes. Since then, there has been a continuation of more focused solutions throughout Te Papa collection stores. A range of mitigation solutions were found for various containers and objects. We bolted, strapped, fastened and netted our way towards better collection storage. Practices around earthquake mitigation became part of our everyday collection management culture.
The work has been a collaboration between collection staff in order to discover the most creative and workable solutions, and these were transferred across collection areas. We will showcase some of our solutions, the elegant and not so elegant, and discuss lessons learnt
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Matahina Power Station elver catch and transfer programme 1996/97
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Managers of Australasian Herbarium Collections (MAHC): A MARK of Curation Excellence
Managers of Australasian Herbarium Collections (MAHC) is a sub-committee of the Council of Heads of Australasian Herbaria (CHAH) and provides advice and recommendations pertaining to the management of herbarium collections. It was formed in 2009 based initially on Australian herbaria, and later incorporated New Zealand herbaria. MAHC currently has 18 member institutions representing both government funded, and university based herbaria, and includes both the largest (National Herbarium of Victoria - MEL) and smallest collections (Macquarie University - MQU) in the region. The group meets in person annually, and holds regular conference phone calls throughout the year.
MAHC has proved itself to be a very cohesive committee, despite time, sizing, staffing, and funding differences. It prides itself in being inclusive, cooperative, collegiate, collaborative and supportive. It has a strong mentor approach toward early career collections managers or those new to collections management. The group has a healthy forward planning outlook, developing, promoting and implementing collections management policy, recommendations, guidelines and standards. This cohesion has resulted in a toolkit of resources that are freely available and strives for a unified world class best practice herbarium curation. Some of these universally agreed tools include templates, biosecurity documents, disaster mitigation and preparation for Nagoya Protocol implementation for Australia and New Zealand.
MAHC supports new international initiatives and manages the day to day running of programmes such as the Global Plants Initiative project imaging all vascular type specimens housed in Australasia. MAHC collaborates with CHAH and the data sub-committee, HISCOM (Herbarium Information Systems Committee), for continued improvements in sharing digital data and specimens via the Australasian Virtual Herbarium (AVH https://avh.chah.org.au/) and Atlas of Living Australia (ALA https://www.ala.org.au/) services.
This talk will use examples to highlight the effectiveness and success of a unified group in: developing standard practice in curation, incorporating improved curation procedures, and its ability to be agile, responding to incidents at an international level