Invasion Impact and Biotic Resistance by Invertebrate Communities

10.26686/wgtn.17003371 ◽

2021 ◽

Author(s):

◽

Habteab Tsegai Habtom

Keyword(s):

Invasive Species ◽

New Zealand ◽

Walking Speed ◽

Biotic Resistance ◽

Interactive Effect ◽

Effect Of Temperature ◽

Beetle Species ◽

Resident Species ◽

Argentine Ants ◽

Arthropod Species

Invasive species have been recognized as one of the greatest threats to global biodiversity and can have dire economic consequences. Yet rates of invasion are increasing due to the fast and growing network of transportation across the globe. The establishment, spread and impact of invasive species are affected by environmental conditions as well as resident species. Species respond differently to the same abiotic factors and different native species can respond either positively or negatively to invasion. The interaction between invasive and resident species, as well as the effect of temperature on invasive species, has gained much attention. The synergistic effect of suboptimal temperature and biotic resistance could have a much stronger limiting or controlling effect on invasive species than either factor alone. Linepithema humile (Argentine ants) are invasive species originally from a Mediterranean climate, but successfully spreading into extra range habitats. The establishment and spread of these ants in temperate New Zealand represents an ideal model system for studying invasion biology in terms of temperature limits and biotic resistance effects. I investigated the changing distribution of the invasive species the Argentine ants over multiple years at five sites in New Zealand. To test whether their rate of spread corresponds with microclimate I investigated their fine-scare distribution patterns and evaluated the number of generations they may develop seasonally and annually in different microhabitat types. I also evaluated their impact on other arthropod species. I conducted a laboratory experiment to evaluate the effect of temperature on their aggression towards other species, walking speed, and foraging abundance. Similarly, I tested the effect of biotic resistance from other ant species (Monomorium antarcticum and Prolasius advenus) with varying colony sizes. I investigated whether there was any interactive effect of temperature and biotic resistance on the Argentine ants. The distribution of Argentine ants had declined across many invasion fronts over the past 7-8 years. They were more likely to be found in concrete, short grass and sandy habitats, which provide warm microsites. Degree-day calculations predicted that they could develop between 2.5 to 3 generations in each of the above microhabitats per year in urban and rural sites while they were predicted to be unable to develop one generation under tree habitats. In tall grass microhabitats they were predicted to develop between 1-1.5 generations per year. The Argentine ants were hypothesised to adversely affect many other arthropod species. Richness and abundance of resident beetle species were negatively correlated with the invasion of the Argentine ants. Areas invaded by the Argentine ants were also associated with a greater number of exotic beetle species, which may imply secondary invasion. Laboratory experiments showed that lowering temperatures below 17°C negatively affected the Argentine ants‟ walking speed, foraging abundance, aggression and their resource control. A high colony size of M. antarcticum (the competing ant species) affected the foraging success of Argentine ants, and the effect was stronger when coupled with unsuitable temperature (17°C and below). Therefore, Argentine ants are weak competitors at low temperature levels. The results of my thesis underline the importance of biotic and abiotic resistances, their interactive effect as well as the effect of the Argentine ants on other species. Based on climatic considerations and the habitat preferences of resident species it may be possible to predict future spread of the Argentine ants. More importantly, knowledge of microhabitat preferences and biotic resistance may help future control measures against Argentine ants based on management of vegetation structure and microhabitat availability.

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The widespread collapse of an invasive species: Argentine ants ( Linepithema humile ) in New Zealand

Biology Letters ◽

10.1098/rsbl.2011.1014 ◽

2011 ◽

Vol 8 (3) ◽

pp. 430-433 ◽

Cited By ~ 34

Author(s):

Meghan Cooling ◽

Stephen Hartley ◽

Dalice A. Sim ◽

Philip J. Lester

Keyword(s):

Climate Change ◽

Invasive Species ◽

New Zealand ◽

Argentine Ant ◽

Environmental Costs ◽

Argentine Ants ◽

Ant Communities ◽

Mean Survival Time ◽

Colony Collapse ◽

Increasing Temperature

Synergies between invasive species and climate change are widely considered to be a major biodiversity threat. However, invasive species are also hypothesized to be susceptible to population collapse, as we demonstrate for a globally important invasive species in New Zealand. We observed Argentine ant populations to have collapsed in 40 per cent of surveyed sites. Populations had a mean survival time of 14.1 years (95% CI = 12.9–15.3 years). Resident ant communities had recovered or partly recovered after their collapse. Our models suggest that climate change will delay colony collapse, as increasing temperature and decreasing rainfall significantly increased their longevity, but only by a few years. Economic and environmental costs of invasive species may be small if populations collapse on their own accord.

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The interface between invasive species science and legal regulation, using Hymenopteran species and their pathogens as a model system

10.26686/wgtn.17131952.v1 ◽

2021 ◽

Author(s):

◽

Evan Brenton-Rule

Keyword(s):

Invasive Species ◽

New Zealand ◽

Biological Invasions ◽

Honey Bee ◽

Legal Regulation ◽

Argentine Ants ◽

Deformed Wing Virus ◽

Introduced Range ◽

The Impact ◽

Bee Virus

Biological invasions are one of the major causes of biodiversity decline on the planet. The key driver of the global movement of invasive species is international trade. As a response to trade driven invasive species risk, international and domestic regulations have been promulgated with the goal of managing the spread and impact of non-native species. My aims in this thesis were twofold. First, my goal was to review a subset of international and domestic regulations with a view to commenting on their fitness for purpose and suggesting potential improvements. Second, I used the example of non-native and invasive Hymenoptera, as well as their pathogens, to illustrate the risks posed by invasive species and gaps in their management. In order to assess international and domestic regulations, I reviewed the World Trade Organization’s (WTO) Agreement on Sanitary and Phytosanitary Measures, as well as associated disputes. I argue that the WTO’s regulatory system does, for the most part, allow domestic regulators to manage invasive species risk as they see fit. Subsequently, the focus of the thesis narrows to investigate New Zealand’s pre- and post-border regime managing invasive species. I argue that New Zealand’s pre-border approach represents international best practice, but the post-border management of species is fragmented. The power to manage invasive species has been delegated to sub-national and regional bodies, which typically approach invasive species management in different ways. This variation has led to regulatory inconsistencies in pests managed and funding allocated. There appears to be a substantial lack of planning in some spaces, such as the risk of aquatic invasions. I make recommendations to ameliorate these inconsistencies. My second aim involved the study of non-native and invasive Hymenoptera in New Zealand, as well as the pathogens they carry, in order to illustrate the risks posed by invasive species and gaps in their management. I show that the globally widespread invasive Argentine ant (Linepithema humile) may play a role in the pathogen dynamics and mortality of honey bee hives where the species occur sympatrically. Hives in the presence of Argentine ants suffered significantly higher mortality rates relative to hives without ants and always had higher levels of a honey bee pathogen Deformed wing virus. I demonstrate that honey bee pathogens are found in a range of invasive Hymenoptera in New Zealand. I amplify entire genomes of the honey bee virus Kashmir bee virus (KBV) from three species of non-native or invasive Hymenoptera (Argentine ants, common wasps and honey bees). I show that there is KBV strain variability within and between regions, but more between regions. Further, I demonstrate the result that as sampled KBV sequence length increases, so too does sampled diversity. These results highlight how ‘an’ invasive species is typically not alone: they carry a range of diseases that are almost always not considered in international and regional management plans. Patterns of non-native Hymenoptera carrying honey bee diseases were not restricted to New Zealand. I used mitochondrial DNA to find the likely origin of invasive populations of the globally distributed invasive German wasp. I demonstrate that German wasps show reduced genetic diversity in the invaded range compared to the native range. Populations in the introduced range are likely to have arrived from different source populations. In some regions there were likely multiple introductions. Other regions are genetically homogenous and represent potential areas for use of gene drive technologies. All four different honey bee pathogens assayed for were found in German wasp populations worldwide. These results highlight how the introduction of one exotic species likely brings a range of pathogens. This example of pathogens in Hymenoptera is likely to be true for nearly all non-native introductions. Many of the impacts of biological invasions, such as predation and competition, are relatively obvious and are frequently studied. However some, such as the impact of pathogens, are unseen and poorly understood. Legal regulation is often a post-hoc response implemented once a problem has already arisen. At a global level regulatory regimes operate relatively effectively. As the focus becomes more granular, such as the case of pathogens of Hymenoptera, fewer controls exists. This thesis helps to reduce uncertainty in this area as well as makes recommendations as to how these risks may be managed.

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Bacterial diversity and viral discovery in the invasive Argentine ant (Linepithema humile)

10.26686/wgtn.17014649.v1 ◽

2021 ◽

Author(s):

◽

Alexandra Sébastien

Keyword(s):

Biological Control ◽

Invasive Species ◽

Population Dynamics ◽

New Zealand ◽

Bacterial Diversity ◽

Linepithema Humile ◽

Argentine Ant ◽

Invasive Ants ◽

Argentine Ants ◽

Species Population

Invasive species can lead to major economic and ecological issues. For this reason, biological controls are being developed in order to help with invasive species population management. Pathogenic bacteria and viruses offer good biological control opportunities as both micro-organisms have played a role in natural population declines. However, beneficial bacteria and viruses associated with the targeted invasive species may interfere with biological controls, by protecting their hosts from infections. Previous knowledge on both pathogenic and beneficial bacteria and viruses present in invasive species may then support the development of an active and efficient biological control. The Argentine ant, Linepithema humile, is a South American invasive ant species that has successfully spread over five continents. The ants were introduced to New Zealand after a complex invasion path, from Argentina their home range to Europe, then to Australia and finally to New Zealand. In their new environments, invasive Argentine ants affect species diversity and can cause agricultural losses. In the absence of any biological controls, the Argentine ant population is controlled by chemical sprays and poison baits. Management of these invasive ants in New Zealand is estimated to cost NZ$ 60 million a year. The Argentine ant population in New Zealand was reported to have unexpectedly declined. It was hypothesised that pathogens were the cause of this population collapse. In this study, bacteria and viruses present in the invasive ants were investigated using 454 sequencing and Illumina sequencing for future developments of possible biological controls for the Argentine ants, and a better understanding of the observed population decline in New Zealand. Bacterial diversity present in Argentine ants either declined or diminished along the invasion pathway. At the same time, the invasive ants maintained a core of nine bacteria genera, including Lactobacillus and Gluconobacter, two bacterial genera with members known for their beneficial associations with honey bees. The presence of these core bacteria may have participated in the success of Argentine ants in their new environments. In the laboratory, the use of ampicillin and gentamicin antibiotics on the ants increased bacterial diversity present in the ants. Furthermore, ampicillin, kanamycin and spectinomycin antibiotic treatments increased ant survival but did not affect the ant fitness or intra-species aggressiveness. Only spectinomycin treated ants presented a higher level of inter-species aggressiveness. Bacterial diversity may play an important role in the ant health and at length population dynamics. Finally, Argentine ants are the hosts of two viruses: the Deformed wing virus (DWV) involved in colony collapse disorder in honey bees, and Linepithema humile virus 1 (LHUV-1), a new virus related to DWV. Both viruses actively replicate within the ants, indicating a possible reservoir role of the ants. However, the effects of the viruses on the ants are not yet known. Further viral infection in the laboratory under different stress conditions and / or antibiotic treatment will give an insight in the role played by these viruses in the observed population collapse of Argentine ants in New Zealand. LHUV-1 may offer a possibility in the development of the first biological control for Argentine ants, depending on its specificity and its effects. This dissertation provides a first insight in the core bacteria as well as potential harmful viruses present in Argentine ants. These bacteria and viruses may play a role in the ant population dynamics. Invasive species may co-introduce harmful pathogens with them, and participate to the spread of local ones. The pathogens may affect both invasive ants and native species population dynamics.

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Interactive effect of climate warming and nitrogen deposition may shift the dynamics of native and invasive species

Journal of Plant Ecology ◽

10.1093/jpe/rtaa071 ◽

2020 ◽

Author(s):

Guang-Qian Ren ◽

Chris B Zou ◽

Ling-Yun Wan ◽

Jacob H Johnson ◽

Jian Li ◽

...

Keyword(s):

Invasive Species ◽

Climate Warming ◽

Native Species ◽

Interactive Effect ◽

N Deposition ◽

Effect Of Temperature ◽

N Availability ◽

N Addition ◽

Artemisia Argyi ◽

Species Dynamics

Abstract Aims Projections of invasive species expansion under a warmer world often do not explicitly consider the concurring nitrogen (N) deposition. It remains largely unknown how the convoluted effect of climate warming and N deposition will shift the native and invasive species dynamics. Here, we hypothesize that the concurring increases in N and temperature would promote growth of invasive species greater than that of native species. Methods A controlled greenhouse experiment was conducted to quantify the growth response of an invasive species (Solidago canadensis L.) and a co-existing native species (Artemisia argyi Levl. et Van) under the effects of climate warming, N deposition and their interactions. Important Findings Due to the strong positive effect of N addition, the interactive effect of temperature increase and N addition resulted in an overall significant increase in growth of both invasive and native species, demonstrating that these manipulations may make microhabitats more favorable to plant growth. However, the relative increases in biomass, height and diameter of invasive S. canadensis were significantly lower than those of native A. argyi. This suggests that the vegetative growth superiority of invasive S. canadensis over the native species A. argyi is reduced by the enhanced N availability in the warmer world. Therefore, the inclusion of N deposition may mitigate the projection of invasive species S. canadensis expansion under climate warming.

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The interface between invasive species science and legal regulation, using Hymenopteran species and their pathogens as a model system

10.26686/wgtn.17131952 ◽

2021 ◽

Author(s):

◽

Evan Brenton-Rule

Keyword(s):

Invasive Species ◽

New Zealand ◽

Biological Invasions ◽

Honey Bee ◽

Legal Regulation ◽

Argentine Ants ◽

Deformed Wing Virus ◽

Introduced Range ◽

The Impact ◽

Bee Virus

Biological invasions are one of the major causes of biodiversity decline on the planet. The key driver of the global movement of invasive species is international trade. As a response to trade driven invasive species risk, international and domestic regulations have been promulgated with the goal of managing the spread and impact of non-native species. My aims in this thesis were twofold. First, my goal was to review a subset of international and domestic regulations with a view to commenting on their fitness for purpose and suggesting potential improvements. Second, I used the example of non-native and invasive Hymenoptera, as well as their pathogens, to illustrate the risks posed by invasive species and gaps in their management. In order to assess international and domestic regulations, I reviewed the World Trade Organization’s (WTO) Agreement on Sanitary and Phytosanitary Measures, as well as associated disputes. I argue that the WTO’s regulatory system does, for the most part, allow domestic regulators to manage invasive species risk as they see fit. Subsequently, the focus of the thesis narrows to investigate New Zealand’s pre- and post-border regime managing invasive species. I argue that New Zealand’s pre-border approach represents international best practice, but the post-border management of species is fragmented. The power to manage invasive species has been delegated to sub-national and regional bodies, which typically approach invasive species management in different ways. This variation has led to regulatory inconsistencies in pests managed and funding allocated. There appears to be a substantial lack of planning in some spaces, such as the risk of aquatic invasions. I make recommendations to ameliorate these inconsistencies. My second aim involved the study of non-native and invasive Hymenoptera in New Zealand, as well as the pathogens they carry, in order to illustrate the risks posed by invasive species and gaps in their management. I show that the globally widespread invasive Argentine ant (Linepithema humile) may play a role in the pathogen dynamics and mortality of honey bee hives where the species occur sympatrically. Hives in the presence of Argentine ants suffered significantly higher mortality rates relative to hives without ants and always had higher levels of a honey bee pathogen Deformed wing virus. I demonstrate that honey bee pathogens are found in a range of invasive Hymenoptera in New Zealand. I amplify entire genomes of the honey bee virus Kashmir bee virus (KBV) from three species of non-native or invasive Hymenoptera (Argentine ants, common wasps and honey bees). I show that there is KBV strain variability within and between regions, but more between regions. Further, I demonstrate the result that as sampled KBV sequence length increases, so too does sampled diversity. These results highlight how ‘an’ invasive species is typically not alone: they carry a range of diseases that are almost always not considered in international and regional management plans. Patterns of non-native Hymenoptera carrying honey bee diseases were not restricted to New Zealand. I used mitochondrial DNA to find the likely origin of invasive populations of the globally distributed invasive German wasp. I demonstrate that German wasps show reduced genetic diversity in the invaded range compared to the native range. Populations in the introduced range are likely to have arrived from different source populations. In some regions there were likely multiple introductions. Other regions are genetically homogenous and represent potential areas for use of gene drive technologies. All four different honey bee pathogens assayed for were found in German wasp populations worldwide. These results highlight how the introduction of one exotic species likely brings a range of pathogens. This example of pathogens in Hymenoptera is likely to be true for nearly all non-native introductions. Many of the impacts of biological invasions, such as predation and competition, are relatively obvious and are frequently studied. However some, such as the impact of pathogens, are unseen and poorly understood. Legal regulation is often a post-hoc response implemented once a problem has already arisen. At a global level regulatory regimes operate relatively effectively. As the focus becomes more granular, such as the case of pathogens of Hymenoptera, fewer controls exists. This thesis helps to reduce uncertainty in this area as well as makes recommendations as to how these risks may be managed.

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Variation in the Persistence and Effects of Argentine Ants throughout Their Invaded Range in New Zealand

10.26686/wgtn.16997518.v1 ◽

2021 ◽

Author(s):

◽

Meghan Dawn Cooling

Keyword(s):

Climate Change ◽

Species Richness ◽

New Zealand ◽

Survival Time ◽

Argentine Ant ◽

Maximum Temperature ◽

Argentine Ants ◽

Ant Communities ◽

Arthropod Species ◽

Species Richness And Abundance

Invasive ants are a serious ecological problem around the world. The Argentine ant has had devastating effects on resident ant communities and may negatively impact other invertebrates in its introduced range. First detected in Auckland in 1990, this invader has since spread widely around the country. The effect of Argentine ants on invertebrates in New Zealand was investigated by comparing ground-dwelling arthropod species richness and abundance between and among paired uninvaded and invaded sites in seven cities across this invader's New Zealand range. In order to study density-dependent effects, invaded sites were chosen so as to differ in Argentine ant population density. The effects of rainfall and mean maximum temperature on Argentine ant abundance and the species richness and abundance were also examined. Argentine ant population persistence in New Zealand was examined by re-surveying sites of past infestation across this species range. The influence of climate on population persistence was investigated, and how this effect may vary after climate change. Additionally, the potential of community recovery after invasion was also examined. Epigaeic (above ground foraging) ant species richness and abundance was negatively associated with Argentine ant abundance; however, no discernable impact was found on hypogaeic (below ground foraging) ant species. The effect of Argentine ant abundance on non-ant arthropod species richness and abundance was mixed, with most arthropod orders being unaffected. Diplopoda was negatively influenced by Argentine ant abundance while Hemiptera was positively influenced. Annual rainfall and mean maximum temperature were found to have no effect on Argentine ant abundance or resident ant species richness and abundance, though these variables did help explain the distribution of several non-ant arthropod orders. Argentine ant populations appear to be collapsing in New Zealand. Populations had a mean survival time of 14.1 years (95% CI= 12.9- 15.3 years). Climate change may prolong population survival, as survival time increased with increasing temperature and decreasing rainfall, but only by a few years. Formerly invaded Auckland ant communities were indistinguishable from those that had never been invaded, suggesting ant communities will recover after Argentine ant collapse.

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Variation in the Persistence and Effects of Argentine Ants throughout Their Invaded Range in New Zealand

10.26686/wgtn.16997518 ◽

2021 ◽

Author(s):

◽

Meghan Dawn Cooling

Keyword(s):

Climate Change ◽

Species Richness ◽

New Zealand ◽

Survival Time ◽

Argentine Ant ◽

Maximum Temperature ◽

Argentine Ants ◽

Ant Communities ◽

Arthropod Species ◽

Species Richness And Abundance

Invasive ants are a serious ecological problem around the world. The Argentine ant has had devastating effects on resident ant communities and may negatively impact other invertebrates in its introduced range. First detected in Auckland in 1990, this invader has since spread widely around the country. The effect of Argentine ants on invertebrates in New Zealand was investigated by comparing ground-dwelling arthropod species richness and abundance between and among paired uninvaded and invaded sites in seven cities across this invader's New Zealand range. In order to study density-dependent effects, invaded sites were chosen so as to differ in Argentine ant population density. The effects of rainfall and mean maximum temperature on Argentine ant abundance and the species richness and abundance were also examined. Argentine ant population persistence in New Zealand was examined by re-surveying sites of past infestation across this species range. The influence of climate on population persistence was investigated, and how this effect may vary after climate change. Additionally, the potential of community recovery after invasion was also examined. Epigaeic (above ground foraging) ant species richness and abundance was negatively associated with Argentine ant abundance; however, no discernable impact was found on hypogaeic (below ground foraging) ant species. The effect of Argentine ant abundance on non-ant arthropod species richness and abundance was mixed, with most arthropod orders being unaffected. Diplopoda was negatively influenced by Argentine ant abundance while Hemiptera was positively influenced. Annual rainfall and mean maximum temperature were found to have no effect on Argentine ant abundance or resident ant species richness and abundance, though these variables did help explain the distribution of several non-ant arthropod orders. Argentine ant populations appear to be collapsing in New Zealand. Populations had a mean survival time of 14.1 years (95% CI= 12.9- 15.3 years). Climate change may prolong population survival, as survival time increased with increasing temperature and decreasing rainfall, but only by a few years. Formerly invaded Auckland ant communities were indistinguishable from those that had never been invaded, suggesting ant communities will recover after Argentine ant collapse.

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Bacterial diversity and viral discovery in the invasive Argentine ant (Linepithema humile)

10.26686/wgtn.17014649 ◽

2021 ◽

Author(s):

◽

Alexandra Sébastien

Keyword(s):

Biological Control ◽

Invasive Species ◽

Population Dynamics ◽

New Zealand ◽

Bacterial Diversity ◽

Linepithema Humile ◽

Argentine Ant ◽

Invasive Ants ◽

Argentine Ants ◽

Species Population

Invasive species can lead to major economic and ecological issues. For this reason, biological controls are being developed in order to help with invasive species population management. Pathogenic bacteria and viruses offer good biological control opportunities as both micro-organisms have played a role in natural population declines. However, beneficial bacteria and viruses associated with the targeted invasive species may interfere with biological controls, by protecting their hosts from infections. Previous knowledge on both pathogenic and beneficial bacteria and viruses present in invasive species may then support the development of an active and efficient biological control. The Argentine ant, Linepithema humile, is a South American invasive ant species that has successfully spread over five continents. The ants were introduced to New Zealand after a complex invasion path, from Argentina their home range to Europe, then to Australia and finally to New Zealand. In their new environments, invasive Argentine ants affect species diversity and can cause agricultural losses. In the absence of any biological controls, the Argentine ant population is controlled by chemical sprays and poison baits. Management of these invasive ants in New Zealand is estimated to cost NZ$ 60 million a year. The Argentine ant population in New Zealand was reported to have unexpectedly declined. It was hypothesised that pathogens were the cause of this population collapse. In this study, bacteria and viruses present in the invasive ants were investigated using 454 sequencing and Illumina sequencing for future developments of possible biological controls for the Argentine ants, and a better understanding of the observed population decline in New Zealand. Bacterial diversity present in Argentine ants either declined or diminished along the invasion pathway. At the same time, the invasive ants maintained a core of nine bacteria genera, including Lactobacillus and Gluconobacter, two bacterial genera with members known for their beneficial associations with honey bees. The presence of these core bacteria may have participated in the success of Argentine ants in their new environments. In the laboratory, the use of ampicillin and gentamicin antibiotics on the ants increased bacterial diversity present in the ants. Furthermore, ampicillin, kanamycin and spectinomycin antibiotic treatments increased ant survival but did not affect the ant fitness or intra-species aggressiveness. Only spectinomycin treated ants presented a higher level of inter-species aggressiveness. Bacterial diversity may play an important role in the ant health and at length population dynamics. Finally, Argentine ants are the hosts of two viruses: the Deformed wing virus (DWV) involved in colony collapse disorder in honey bees, and Linepithema humile virus 1 (LHUV-1), a new virus related to DWV. Both viruses actively replicate within the ants, indicating a possible reservoir role of the ants. However, the effects of the viruses on the ants are not yet known. Further viral infection in the laboratory under different stress conditions and / or antibiotic treatment will give an insight in the role played by these viruses in the observed population collapse of Argentine ants in New Zealand. LHUV-1 may offer a possibility in the development of the first biological control for Argentine ants, depending on its specificity and its effects. This dissertation provides a first insight in the core bacteria as well as potential harmful viruses present in Argentine ants. These bacteria and viruses may play a role in the ant population dynamics. Invasive species may co-introduce harmful pathogens with them, and participate to the spread of local ones. The pathogens may affect both invasive ants and native species population dynamics.

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New Zealand’s Assistance with Invasive Species Management in the Pacific

10.26686/wgtn.16992301 ◽

2021 ◽

Author(s):

◽

Simon Lovatt

Keyword(s):

Invasive Species ◽

New Zealand ◽

International Development ◽

Biodiversity Loss ◽

Well Being ◽

Leadership Role ◽

Invasive Species Management ◽

The Pacific ◽

Species Management ◽

Critical Leadership

Invasive species are one of the biggest threats to development and well-being in the Pacific. They have wide-ranging impacts on economies, the environment, and societies; in addition to causing USD $1.4 trillion of losses each year. Invasive species are also the primary cause of biodiversity loss on islands which could significantly affect the ecosystem services which Pacific Islanders depend on. Every year New Zealand spends NZD $500 million on biosecurity, and Australia has spent AUD $175 million on a single eradication project. In comparison, in the Pacific there are only six people working fulltime on invasive species issues at a regional level and there is limited funding available. This thesis assesses the role of four New Zealand agencies that assist with invasive species management in the Pacific: the International Development Group of the Ministry of Foreign Affairs, the Biosecurity New Zealand division of the Ministry of Agriculture and Forestry, the Department of Conservation, and Landcare Research. Together these agencies provide funding, build capacity, offer technical advice, and occasionally implement projects. While there are important gains to New Zealand in assisting the Pacific with invasive species management, such as a reduced biosecurity threat and learning opportunities for staff, the desire to help the region for its own sake is a major driver. Suggestions for future improvement include having more information on the economic impacts of invasive species in the Pacific, increased coordination between donors, and including invasive species measures in regional trade agreements. It is hoped that New Zealand will continue to play its critical leadership role in invasive species management in the region.

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