ORCID Profile
0000-0001-5402-0611
Current Organisations
Manaaki Whenua - Landcare Research
,
University of Adelaide
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Publisher: Pensoft Publishers
Date: 05-08-2020
DOI: 10.3897/NEOBIOTA.59.52022
Abstract: Invasive Alien Species (IAS) threaten bio ersity, ecosystem functions and services, modify landscapes and impose costs to national economies. Management efforts are underway globally to reduce these impacts, but little attention has been paid to optimising the use of the scarce available resources when IAS are impossible to eradicate, and therefore population reduction and containment of their advance are the only feasible solutions. CONTAIN, a three-year multinational project involving partners from Argentina, Brazil, Chile and the UK, started in 2019. It develops and tests, via case study ex les, a decision-making toolbox for managing different problematic IAS over large spatial extents. Given that vast areas are invaded, spatial prioritisation of management is necessary, often based on sparse data. In turn, these characteristics imply the need to make the best decisions possible under likely heavy uncertainty. Our decision-support toolbox will integrate the following components: (i) the relevant environmental, social, cultural, and economic impacts, including their spatial distribution (ii) the spatio-temporal dynamics of the target IAS (focusing on dispersal and population recovery) (iii) the relationship between the abundance of the IAS and its impacts (iv) economic methods to estimate both benefits and costs to inform the spatial prioritisation of cost-effective interventions. To ensure that our approach is relevant for different contexts in Latin America, we are working with model species having contrasting modes of dispersal, which have large environmental and/or economic impacts, and for which data already exist (invasive pines, privet, wasps, and American mink). We will also model plausible scenarios for data-poor pine and grass species, which impact local people in Argentina, Brazil and Chile. We seek the most effective strategic management actions supported by empirical data on the species’ population dynamics and dispersal that underpin reinvasion, and on intervention costs in a spatial context. Our toolbox serves to identify key uncertainties driving the systems, and especially to highlight gaps where new data would most effectively reduce uncertainty on the best course of action. The problems we are tackling are complex, and we are embedding them in a process of co-operative adaptive management, so that both researchers and managers continually improve their effectiveness by confronting different models to data. Our project is also building research capacity in Latin America by sharing knowledge/information between countries and disciplines (i.e., biological, social and economic), by training early-career researchers through research visits, through our continuous collaboration with other researchers and by training and engaging stakeholders via workshops. Finally, all these activities will establish an international network of researchers, managers and decision-makers. We expect that our lessons learned will be of use in other regions of the world where complex and inherently context-specific realities shape how societies deal with IAS.
Publisher: CSIRO Publishing
Date: 04-11-2021
DOI: 10.1071/PC21057
Abstract: Context Illegal wildlife trade (IWT) is a leading concern for conservation and biosecurity agencies globally, and involves multiple source, transit, and destination countries smuggling species on a transnational scale. The contribution of non-range countries for driving demand in IWT is often overlooked. Aims We analysed the dynamics (source, type and quantity) of bear seizures in Australia and New Zealand to gain a deeper understanding of the IWT, and to raise awareness among enforcement agencies for mitigating the international smuggling of bear parts and derivatives, and reducing the global threat to bears from illegal exploitation. Methods We collated biosecurity and conservation enforcement agency records of CITES seizures from Australia and New Zealand. All of the seizures were declared for ‘personal use’. Key results We report on 781 seizures of bear parts and derivatives in Australia and New Zealand from 33 countries over the past decade. The majority of seizures were medicinal (gall bladder and bile) products, but also included a range of body parts, hunting trophies and meat. China was the source of the greatest number of seizures, however, 32 additional source and transit countries/territories (from Asia, Europe, Americas, Middle East and Africa) were also involved in the seizures of bear parts and their derivatives. Conclusions The widespread trade of bears is an ex le of the far-reaching consequences commercial use can have on threatened species. Australia and New Zealand have no native bear species, and yet are frequently involved in wildlife seizures, and illegal bear trade continues to be an enforcement issue. Implications IWT has a detrimental impact on the conservation of bears. Conservation research in non-range countries needs to be conducted to determine the demand and threats from IWT, and to increase collaborative strategies to counter transnational smuggling.
Publisher: Wiley
Date: 09-2010
DOI: 10.2981/09-025
Abstract: The American mink Neovison vison is a widely distributed species in Spain, for which important basic ecological data are lacking. We studied mink den site selection in a location in central Spain during the winter of 2008/09 using snow‐tracking and direct observation. Dens were located more frequently in tree roots (51.9% N = 79) inside emergent vegetation (15.2%) and on human‐created enbankments (15.2%). Human buildings and burrows were scarcely used ( 10%). The logistic regressions we carried out supported that minks used secondary river beds for shelter more often than their availability in the environment should predict. These secondary areas are characterised by their low width and the frequent presence of small streams (of 1m width). In rough terms, this pattern could be a way of avoiding potential interactions with other animals sharing the same habitat, and also for thermoregulation while resting. On the basis of the wide habitat niche, ecosystem management as a measure of mink control appears to be ineffective.
Publisher: Wiley
Date: 02-2019
DOI: 10.1002/CSP2.11
Publisher: Springer Science and Business Media LLC
Date: 16-06-2017
Publisher: Wiley
Date: 23-12-2015
DOI: 10.1111/GCB.12790
Abstract: Biological invasions are a key component of human‐induced global change. The continuing increase in global wildlife trade has raised concerns about the parallel increase in the number of new invasive species. However, the factors that link the wildlife trade to the biological invasion process are still poorly understood. Moreover, there are analytical challenges in researching the role of global wildlife trade in biological invasions, particularly issues related to the under‐reporting of introduced and established populations in areas with reduced s ling effort. In this work, we use high‐quality data on the international trade in Nearctic turtles (1999–2009) coupled with a statistical modelling framework, which explicitly accounts for detection, to investigate the factors that influence the introduction (release, or escape into the wild) of globally traded Nearctic turtles and the establishment success (self‐sustaining exotic populations) of slider turtles ( Trachemys scripta ), the most frequently traded turtle species. We found that the introduction of a species was influenced by the total number of turtles exported to a jurisdiction and the age at maturity of the species, while the establishment success of slider turtles was best associated with the propagule number (number of release events), and the number of native turtles in the jurisdiction of introduction. These results indicate both a direct and indirect association between the wildlife trade and the introduction of turtles and establishment success of slider turtles, respectively. Our results highlight the existence of gaps in the number of globally recorded introduction events and established populations of slider turtles, although the expected bias is low. We emphasize the importance of researching independently the factors that affect the different stages of the invasion pathway. Critically, we observe that the number of traded in iduals might not always be an adequate proxy for propagule pressure and establishment success.
Publisher: Public Library of Science (PLoS)
Date: 29-12-2021
DOI: 10.1371/JOURNAL.PCBI.1009660
Abstract: Invasive rodent populations pose a threat to bio ersity across the globe. When confronted with these invaders, native species that evolved independently are often defenseless. CRISPR gene drive systems could provide a solution to this problem by spreading transgenes among invaders that induce population collapse, and could be deployed even where traditional control methods are impractical or prohibitively expensive. Here, we develop a high-fidelity model of an island population of invasive rodents that includes three types of suppression gene drive systems. The in idual-based model is spatially explicit, allows for overlapping generations and a fluctuating population size, and includes variables for drive fitness, efficiency, resistance allele formation rate, as well as a variety of ecological parameters. The computational burden of evaluating a model with such a high number of parameters presents a substantial barrier to a comprehensive understanding of its outcome space. We therefore accompany our population model with a meta-model that utilizes supervised machine learning to approximate the outcome space of the underlying model with a high degree of accuracy. This enables us to conduct an exhaustive inquiry of the population model, including variance-based sensitivity analyses using tens of millions of evaluations. Our results suggest that sufficiently capable gene drive systems have the potential to eliminate island populations of rodents under a wide range of demographic assumptions, though only if resistance can be kept to a minimal level. This study highlights the power of supervised machine learning to identify the key parameters and processes that determine the population dynamics of a complex evolutionary system.
Publisher: Cambridge University Press (CUP)
Date: 22-04-2020
DOI: 10.1017/S0376892920000132
Abstract: Alien species are a driver of bio ersity loss, with impacts of different aliens on native species varying considerably. Identifying the contributions of alien species to native species declines could help target management efforts. Globally, seabirds breeding on islands have proven to be highly susceptible to alien species. The breeding colonies of the pink-footed shearwater ( Ardenna creatopus ) are threatened by the negative impacts of alien mammals. We combined breeding monitoring data with a hierarchical model to separate the effects of different alien mammal assemblages on the burrow occupancy and hatching success of the pink-footed shearwater in the Juan Fernández Archipelago, Chile. We show that alien mammals affected the rates of burrow occupancy, but had little effect on hatching success. Rabbits produced the highest negative impacts on burrow occupancy, whereas the effects of other alien mammals were more uncertain. In addition, we found differences in burrow occupancy between islands regardless of their alien mammal assemblages. Managing rabbits will improve the reproductive performance of this shearwater, but research is needed to clarify the mechanisms by which alien mammals affect the shearwaters and to explain why burrow occupancy varies between islands.
Publisher: Wiley
Date: 03-02-2014
DOI: 10.1111/DDI.12176
Publisher: Springer Science and Business Media LLC
Date: 2021
Publisher: Springer Science and Business Media LLC
Date: 2011
Publisher: Wiley
Date: 24-02-2022
Abstract: The pet trade is a major driver of both bio ersity loss and the introduction of invasive alien species. Building a comprehensive understanding of the pet trade would improve prediction of conservation and biosecurity threats, with the aim to prevent further negative impacts. We used South Australia’s native wildlife permit reporting system as a data‐rich ex le of a vertebrate pet market, spanning 590 distinct taxa across 105 families of terrestrial vertebrates (mammals, reptiles, birds and hibians). Using a piecewise structural equation modelling (SEM) approach, we tested the influence of 11 a priori variables relating to pets (e.g. species traits), pet owners (e.g. socioeconomic metrics) and regulatory systems (e.g. permit requirements) on the quantities of captive pet keeping, breeding, trading and escapes into the wild. Birds and reptiles with higher annual fecundity were more likely to be kept in captivity and birds with larger adult mass were more likely to be sold. Species with more stringent permit requirements were possessed and escaped, in lower abundances. Pet keeping was weakly correlated with regions of lower human population densities and higher unemployment rates, yet all socioeconomic variables were ultimately poor at explaining trade dynamics. More escapes occurred in regions that possessed larger quantities of pets, further emphasising the role of propagule pressure in the risk of pet escapes. Synthesis and applications . Species traits are a strong determinant of native pet trade dynamics, yet permit systems also play a key role in de‐incentivising undesirable trade practices. While our research highlighted the positive potential of trade regulatory systems, we recommend that consistent permit category criteria are established to reduce trade in threatened species as well as invasive alien species of high biosecurity risk. Implementation of such systems is broadly needed across a greater ersity of wildlife markets and jurisdictions.
Publisher: Wiley
Date: 20-05-2018
DOI: 10.1111/DDI.12777
Publisher: Walter de Gruyter GmbH
Date: 2009
Publisher: Springer Science and Business Media LLC
Date: 15-03-2019
Publisher: Springer Science and Business Media LLC
Date: 29-09-0011
DOI: 10.1007/S00267-021-01541-3
Abstract: Formulating effective management plans for addressing the impacts of invasive non-native species (INNS) requires the definition of clear priorities and tangible targets, and the recognition of the plurality of societal values assigned to these species. These tasks require a multi-disciplinary approach and the involvement of stakeholders. Here, we describe procedures to integrate multiple sources of information to formulate management priorities, targets, and high-level actions for the management of INNS. We follow five good-practice criteria: justified, evidence-informed, actionable, quantifiable, and flexible. We used expert knowledge methods to compile 17 lists of ecological, social, and economic impacts of lodgepole pines ( Pinus contorta ) and American mink ( Neovison vison ) in Chile and Argentina, the privet ( Ligustrum lucidum ) in Argentina, the yellow-jacket wasp ( Vespula germanica ) in Chile, and grasses ( Urochloa brizantha and Urochloa decumbens ) in Brazil. INNS plants caused a greater number of impacts than INNS animals, although more socio-economic impacts were listed for INNS animals than for plants. These impacts were ranked according to their magnitude and level of confidence on the information used for the ranking to prioritise impacts and assign them one of four high-level actions—do nothing, monitor, research, and immediate active management. We showed that it is possible to formulate management priorities, targets, and high-level actions for a variety of INNS and with variable levels of available information. This is vital in a world where the problems caused by INNS continue to increase, and there is a parallel growth in the implementation of management plans to deal with them.
Publisher: Elsevier BV
Date: 2023
DOI: 10.1016/J.JENVMAN.2022.116480
Abstract: Biological invasions produce negative impacts worldwide, causing massive economic costs and ecological impacts. Knowing the relationship between invasive species abundance and the magnitude of their impacts (abundance-impact curves) is critical to designing prevention and management strategies that effectively tackle these impacts. However, different measures of abundance may produce different abundance-impact curves. Woody plants are among the most transformative invaders, especially in grassland ecosystems because of the introduction of hitherto absent life forms. In this study, our first goal was to assess the impact of a woody invader, Pinus contorta (hereafter pine), on native grassland productivity and livestock grazing in Patagonia (Argentina), building abundance-impact curves. Our second goal, was to compare different measure of pine abundance (density, basal area and canopy cover) as predictors of pine's impact on grassland productivity. Our third goal, was to compare abundance-impact curves among the mentioned measures of pine abundance and among different measures of impact: total grassland productivity, palatable productivity and sheep stocking rate (the number of sheep that the grassland can sustainably support). Pine canopy cover, closely followed by basal area, was the measure of abundance that best explained the impact on grassland productivity, but the shape of abundance impact curves differed between measures of abundance. While increases in pine density and basal area always reduced grassland productivity, pine canopy cover below 30% slightly increased grassland productivity and higher values caused an exponential decline. This increase in grassland productivity with low levels of pine canopy cover could be explained by the amelioration of stressful abiotic conditions for grassland species. Different measures of impact, namely total productivity, palatable productivity and sheep stocking rate, drew very similar results. Our abundance-impact curves are key to guide the management of invasive pines because a proper assessment of how many invasive in iduals (per surface unit) are unacceptable, according to environmental or economic impact thresholds, is fundamental to define when to start management actions.
Publisher: Wiley
Date: 02-2019
DOI: 10.1111/CSP2.11
Publisher: Wiley
Date: 10-2023
Publisher: Springer Science and Business Media LLC
Date: 24-05-2013
Publisher: Wiley
Date: 27-10-2016
DOI: 10.1111/CONL.12301
Publisher: Springer Science and Business Media LLC
Date: 02-2013
Publisher: Pensoft Publishers
Date: 14-09-2016
No related grants have been discovered for Pablo García Díaz.