Detection Of Incursions Research Articles

Systematic review of the impact of restrictive wildlife trade measures on conservation of iconic species in southern Africa.

Trade restrictions are often advocated and implemented as measures to protect wild species threatened by overexploitation. However, in some instances, their efficacy has been questioned, notably by governments in the southern African (SADC) region, which tend to favor a sustainable use approach to wildlife management. We conducted a systematic review of published literature guided by the PRISMA process to examine the effectiveness of trade restrictions and directly related control measures in addressing threats to species conservation in the SADC region, with a focus on elephants (Loxodonta sp.), rhinoceroses (Ceratotherium simum, Diceros bicornis), lions (Panthera leo), and pangolins (Manis sp.). We focused in particular on the direct conservation impact of trade restrictions at species or population level, indirect conservation impact at human behavior or attitude level, and socioeconomic impact on rural livelihoods and well-being and on national economies. Research on these topics was uneven and focused strongly on the effects of trade restrictions and law enforcement on crime-related behavior. Research gaps include socioeconomic impacts of trade restrictions, including effects of international restrictions on local livelihoods and consequent secondary conservation impacts, and evaluations of attempts to disrupt criminal networks. Based on the reviewed impact evidence, the effectiveness of international trade restrictions depends on a range of fully aligned measures in countries of origin, transit, and consumption. For example, our results suggest positive ecological short-term but negative or unknown long-term socioeconomic impacts of domestic restrictions. Based on these findings, key policy requirements include more nuanced approaches to incorporate a range of appropriate measures in range, transit, and consumer countries, that focus on capacity development for early detection and apprehension of incursions inside protected areas; measures for constructive engagement with relevant local communities outside protected areas; and future research to improve understanding of the socioeconomic contribution of wildlife.

Oral Fluids for the Early Detection of Classical Swine Fever in Commercial Level Pig Pens.

The early detection of classical swine fever (CSF) remains a key challenge, especially when outbreaks are caused by moderate and low-virulent CSF virus (CSFV) strains. Oral fluid is a reliable and cost-effective sample type that is regularly surveilled for endemic diseases in commercial pig herds in North America. Here, we explored the possibility of utilizing oral fluids for the early detection of CSFV incursions in commercial-size pig pens using two independent experiments. In the first experiment, a seeder pig infected with the moderately-virulent CSFV Pinillos strain was used, and in the second experiment, a seeder pig infected with the highly-virulent CSFV Koslov strain was used. Pen-based oral fluid samples were collected daily and individual samples (whole blood, swabs) every other day. All samples were tested by a CSFV-specific real-time RT-PCR assay. CSFV genomic material was detected in oral fluids on the seventh and fourth day post-introduction of the seeder pig into the pen, in the first and second experiments, respectively. In both experiments, oral fluids tested positive before the contact pigs developed viremia, and with no apparent sick pigs in the pen. These results indicate that pen-based oral fluids are a reliable and convenient sample type for the early detection of CSF, and therefore, can be used to supplement the ongoing CSF surveillance activities in North America.

Citizen science delivers high-value biosecurity surveillance and reporting capability

Context Early surveillance and the detection of incursions of species of biosecurity concern are a crucial component of an effective biosecurity system. Citizen science represents an opportunity to engage communities in biosecurity, and to provide mechanisms for citizen scientists to contribute to both monitoring the spread of species already present in country, and reporting new incursions. Aims To present an example of how citizen science is being used for environmental biosecurity surveillance in Australia and showcase the value of large data services such as the Atlas of Living Australia (ALA), as a connector between citizen science and management. Methods We detail how the alert email system was set up, using a bespoke solution implemented in the R programming language. The system works by querying the ALA database for species that match lists provided by management authorities. Alerts can be sent out at national, state/territory and local government scales, as well as defined spatial areas such as national park estates. Key results Twelve months in, the top source for alerts comes from iNaturalist (a popular global biodiversity citizen-science platform), with other contributions from a set of biodiversity-reporting applications. Over a 12-month period, the alerts service has provided notifications for over 150 species, including the first public record of an invasive species in Australia. Conclusions Systems such as the Biosecurity Alerts Service, provide impact through the connection between communities and decision-making. Implications Our findings showed how the advancement of citizen science is interconnected with the advancement of research infrastructure and will ultimately lead to greater scientific and management value of citizen-science data.

Invasions, Plagues, and Epidemics: The Atlas of Living Australia’s deep dive into biosecurity

Early detection of new incursions of species of biosecurity concern is crucial to protecting Australia’s environment, agriculture, and cultural heritage. As Australia’s largest biodiversity data repository, the Atlas of Living Australia (ALA) is often the first platform where new species incursions are recorded. The ALA holds records of more than 2,380 exotic species and over 1.9 million occurrences of pests, weeds, and diseases—many of which are reported though citizen science. However, until recently there has been no systematic mechanism for notifying relevant biosecurity authorities of potential biosecurity threats. To address this, the ALA partnered with the (Australian) Commonwealth Department of Agriculture, Fisheries and Forestry to develop the Biosecurity Alerts System. Two years on, the project has demonstrated the benefits of biosecurity alerts, but significant barriers exist as we now work to expand this system to State and Territory biosecurity agencies, and seek new sources of biosecurity data. In our presentation, we discuss a brief history of invasive alien species in Australia, the Biosecurity Alerts System, and how we are approaching issues with taxonomy, data standards, and cultural sensitivities in aggregating biosecurity data. We conclude by detailing our progress in expanding the alerts system and tackling systemic issues to help elevate Australia’s biosecurity system.

An integrative approach to assess non‐native iguana presence on Saba and Montserrat: Are we losing all native Iguana populations in the Lesser Antilles?

AbstractInvasive alien species are among the main drivers of the ongoing sixth mass extinction wave, especially affecting island populations. Although the Caribbean is well‐known for its high species richness and endemism, also for reptiles, equally important is the regional contribution of non‐native species to island biodiversity. The Lesser Antilles encompass high genetic diversity in Iguana, though most native populations either have gone extinct or are declining following competitive hybridization with invasive non‐native green iguanas. Here, we assessed non‐native presence in two poorly‐studied native melanistic Iguana iguana populations using available genetic tools and explored utilizing size‐dependent body measurements to discriminate between native and non‐native iguanas. Genetic samples from Saba and Montserrat were genotyped across 17 microsatellite loci with STRUCTURE, and multivariate analyses indicating non‐native iguana presence only on Saba. This was corroborated by mtDNA and nDNA sequences, highlighting a non‐native origin in Central America and the ABC islands. We identified preliminary evidence suggestive of hybridization. Morphological variation among size‐dependent characteristics showed that non‐native iguanas have significantly larger subtympanic plates than native iguanas. Non‐native individuals also differed in scalation and coloration patterns. Overall, our findings demonstrate the need for continuous monitoring of non‐native iguanas within remaining native Iguana populations in the Lesser Antilles, as those not directly threatened by non‐native green iguanas are restricted to only 8.7% of the historic range. Although genetic data allow for the identification of non‐native or hybrid iguana presence, this field‐to‐lab workflow is time‐consuming. Rapid in‐situ identification of non‐native individuals is crucial for conservation management. In addition to patterns of scalation and coloration, we have highlighted the utility of size‐dependent variables for rapid diagnosis. We urge regional partners to build morphometric databases for native Iguana populations allowing the quick detection of future incursions of non‐native green iguanas and the rapid implementation of effective countermeasures during the early phase of invasion.

Do we need to mine social media data to detect exotic vertebrate-pest introductions?

Invasive alien species are responsible for considerable biodiversity loss and environmental damage. Timely detection of new incursions is critical in preventing novel populations establishing. Citizen reports currently account for the majority of alien species detections, arising from the massive observation effort that the physical and digital ‘eyes and ears’ of citizens provide, in combination with crowd-sourced species identification. Because the reporting of alien species sightings is generally not mandatory, there is interest in whether mining social media data via image recognition and/or natural language processing can improve on existing passive citizen surveillance in a cost-effective manner. Here, we illustrate, using examples from Australia, how citizen surveillance for most vertebrate groups appears to currently be effective using existing voluntary reporting mechanisms. Where citizen surveillance is currently ineffective, for reasons of inadequate sampling, data mining of social media feeds will be similarly affected. We argue that mining citizens’ social media data for evidence of invasive alien species needs to demonstrate not only that it will be an improvement on the business as usual case, but also that any gains achieved cannot be achieved by alternative approaches. We highlight the potential role of education in increasing the surveillance effectiveness of citizens for detecting and reporting sightings of alien species. Should data mining of social media platforms be pursued, we note that the scale of the task in terms of the potential number of exotic vertebrate species to be classified is very large. The expected number of false positive classifications would present a considerable workload to process, possibly undermining the efficiency rationale for the use of data mining. Hence, prioritisation is needed, and we illustrate how the number of species to be classified can be reduced considerably. If we are to deploy data mining and analysis of social media data to help with detecting introductions of invasive alien species, we need to conduct it in a manner where it adds value and is trusted.

Epidemiologically-based strategies for the detection of emerging plant pathogens

Emerging pests and pathogens of plants are a major threat to natural and managed ecosystems worldwide. Whilst it is well accepted that surveillance activities are key to both the early detection of new incursions and the ability to identify pest-free areas, the performance of these activities must be evaluated to ensure they are fit for purpose. This requires consideration of the number of potential hosts inspected or tested as well as the epidemiology of the pathogen and the detection method used. In the case of plant pathogens, one particular concern is whether the visual inspection of plant hosts for signs of disease is able to detect the presence of these pathogens at low prevalences, given that it takes time for these symptoms to develop. One such pathogen is the ST53 strain of the vector-borne bacterial pathogen Xylella fastidiosa in olive hosts, which was first identified in southern Italy in 2013. Additionally, X. fastidiosa ST53 in olive has a rapid rate of spread, which could also have important implications for surveillance. In the current study, we evaluate how well visual surveillance would be expected to perform for this pathogen and investigate whether molecular testing of either tree hosts or insect vectors offer feasible alternatives. Our results identify the main constraints to each of these strategies and can be used to inform and improve both current and future surveillance activities.

A pan-coronavirus RT-PCR assay for rapid viral screening of animal, human, and environmental specimens

We examined a collection of 386 animal, 451 human, and 109 archived bioaerosol samples with a new pan-species coronavirus molecular assay. Thirty-eight (4.02%) of 946 specimens yielded evidence of human or animal coronaviruses. Our findings demonstrate the utility of employing the pan-CoV RT-PCR assay in detecting varied coronavirus among human, animal, and environmental specimens. This RT-PCR assay might be employed as a screening diagnostic for early detection of coronaviruses incursions or prepandemic coronavirus emergence in animal or human populations.

Working towards a Co-Ordinated Approach to Invasive Mosquito Detection, Response and Control in the UK.

The United Kingdom (UK) has reported a single detection of the eggs of the invasive mosquito vector Aedes albopictus in each of the three years from 2016 to 2018, all in southeast England. Here, we report the detection of mosquito eggs on three occasions at two sites in London and southeast England in September 2019. Mosquito traps were deployed at 56 sites, in England, Scotland, Wales, and Northern Ireland, as part of a coordinated surveillance programme with local authorities, Edge Hill University, and government departments. Response to each detection was coordinated by Public Health England’s (PHE) local health protection teams, with technical support from PHE’s Medical Entomology group, and control conducted by the respective local authority. Control, including source reduction and larviciding, was conducted within a 300 metre radius of the positive site. The response followed a National Contingency Plan for Invasive Mosquitoes: Detection of Incursions. Although the response to these incidents was rapid and well co-ordinated, recommendations are made to further develop mosquito surveillance and control capability for the UK.

Keeping up with introduced marine species at a remote biodiversity hotspot: awareness, training and collaboration across different sectors is key

Despite being a well-recognized issue, the introduction of non-native marine species is an underestimated topic in highly biodiverse developing countries. The Indonesian archipelago sits at the center of the Coral Triangle, extending over several biogeographic regions with unique benthic communities, where the extent of non-native species presence is largely unknown. It is also at the center of maritime traffic between Australasia and Asia, and therefore at risk of introduction of species that are carried on the hulls and ballast water of vessels. In the present study, we aimed to raise awareness on marine biological invasions across the Indonesian archipelago by fostering discussions among scientists, educating science students, generating media articles for the public and actively involving island communities. We also aimed to test the suitability of a range of methods commonly used in bioinvasion research (settlement arrays, DNA barcoding and environmental DNA metabarcoding, vessel surveys) to establish a baseline for biofouling species and potential threats, while developing much needed capacity for monitoring and application to other areas. We recorded 66 different non-coral specimens in the fouling communities of a remote group of islands of the Indonesian archipelago, represented mainly by the taxa Porifera, Tunicata and Mollusca, which are known to include notorious invasive species. None of the identified species was known to be invasive in the region but several were cryptogenic and/or were considered to have a very broad global distribution range that can potentially include part, or all, of the Indonesian archipelago. One species, the ascidian Didemnum molle, was found to quickly settle and spread on available blank substrates. While settlement plates (monitored every 5 months) proved suitable for early detection of potential incursions of these organisms, benthic surveys, DNA barcoding and eDNA metabarcoding provide valuable complementary baseline biodiversity information. A combination of sampling methods is therefore recommended for similar studies in understudied high biodiversity areas. Results from vessel surveys highlights the importance of civil society education in helping prevent bioinvasions. This study represents the first marine biological invasions baseline, awareness and capacity development training carried in the Indonesian archipelago. The lessons taken from the variety of methods explored in a simultaneously scientific and educational setting should prove useful and motivate similar work in other areas of the world.

A novel reassortant clade 2.3.4.4 highly pathogenic avian influenza H5N6 virus identified in South Korea in 2018

Since 2017, clade 2.3.4.4b H5N6 highly pathogenic avian influenza viruses (HPAIVs) have been detected over a broad geographic region, including Eurasia. These viruses have evolved through reassortment with Eurasian low pathogenic avian influenza viruses (LPAIVs), resulting in multiple genotypes. Here, we sequenced the full-length genome of 15 H5N6 HPAIVs collected from wild birds and poultry farms in South Korea from January to March 2018. A comparative phylogenetic analysis was then conducted. Three distinct genotypes were identified in South Korea during 2017/2018, including a novel reassortant genotype, H214. The novel reassortant H5N6 viruses isolated in this study possessed PB2, PA, and NP gene segments of Eurasian LPAIV on a genetic backbone of the H35-like genotype, which was identified in Korea and the Netherlands during 2017. Bayesian molecular clock analysis suggested that the novel reassortant viruses were generated most likely during the fall migration/wintering season of migratory waterfowl in 2017. Considering the continued emergence and spread of clade 2.3.4.4 HPAIV, enhanced surveillance of wild waterfowl is needed for early detection of HPAIV incursions.

Evaluation of Probodelt cone traps for surveillance of Dacinae in New South Wales, Australia

Early detection of Dacinae (Diptera: Tephritidae) incursions is vital for quick and effective management. A key method for early detection is the implementation of trapping networks in risk areas. Australia relies on the use of extensive trapping networks at, and surrounding, major ports and fruit production areas to identity any fruit fly incursions. Therefore, improvements to the trap efficiency of these networks may result in earlier detection of incursions and hence more rapid response times for management and/or eradication. The current Australian standard, the Lynfield trap, is expensive and does not stack readily for transport. Here, we test the effectiveness of a new trap type, the Probodelt cone trap, compared to the Lynfield trap. We ran three separate trials: an experimental trial in an inland orchard and two field trials using the Sydney trapping network. At the orchard site, Lynfield and Probodelt traps had similar capture rates (within 10%) for Bactrocera tryoni. For the Sydney trapping network, no significant differences were found in the number of species caught or trap rates for B. tryoni, Bactrocera cacuminata, Dacus absonifacies, and Dacus aequalis. Thus, the Probodelt cone trap was at least comparable to the Lynfield trap. Given the economic advantages of the Probodelt cone trap (e.g. reduced shipping and storage costs), the use of the Probodelt trap may be preferred over the Lynfield trap.

Cost-effectiveness analysis of One Health surveillance strategies for rabies control

Cost-effectiveness analysis of One Health surveillance strategies for rabies control

Quantifying the hidden costs of imperfect detection for early detection surveillance.

The global spread of pathogens poses an increasing threat to health, ecosystems and agriculture worldwide. As early detection of new incursions is key to effective control, new diagnostic tests that can detect pathogen presence shortly after initial infection hold great potential for detection of infection in individual hosts. However, these tests may be too expensive to be implemented at the sampling intensities required for early detection of a new epidemic at the population level. To evaluate the trade-off between earlier and/or more reliable detection and higher deployment costs, we need to consider the impacts of test performance, test cost and pathogen epidemiology. Regarding test performance, the period before new infections can be first detected and the probability of detecting them are of particular importance. We propose a generic framework that can be easily used to evaluate a variety of different detection methods and identify important characteristics of the pathogen and the detection method to consider when planning early detection surveillance. We demonstrate the application of our method using the plant pathogen Phytophthora ramorum in the UK, and find that visual inspec-tion for this pathogen is a more cost-effective strategy for early detection surveillance than an early detection diagnostic test.This article is part of the theme issue ‘Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control’. This theme issue is linked with the earlier issue ‘Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes’.

PCR-based assay for Mya arenaria detection from marine environmental samples and tracking its invasion in coastal ecosystems

The introduction of invasive species into a new environment is one of the most important factors implicated in loss of native biodiversity. Their early detection is indispensable to efficient control and management response, because after their incursion and establishment the eradication is nearly impossible. The Mediterranean Sea is one of the world´s hotspots of biological invasions and existing monitoring programs are often insufficient for effective surveillance of the established invasive populations or early detection of new incursions. The aim of the current study was to design a specific molecular marker for detecting and monitoring the soft shell clam Mya arenaria, listed among 100 Mediterranean Worst Invasive Species, from environmental samples. The 16S marker was designed in silico and validated in vitro on serial dilutions of M. arenaria DNA and other closely related mollusk species; its performance was also tested on complex environmental samples collected from locations in the Baltic Sea with known established M. arenaria population. The new marker allows amplifying small fragments of 279 bp and detecting as low as 0.00103 ng/μl of M. arenaria DNA with no cross-amplification detected. We suggest the use of this and other species-specific markers for targeted surveillance of invasive species and prompt detection of the prospective incursions. Such monitoring approach has the potential to be adopted by citizen science programs due to its easy implementation, minimal technical skills requirements and reasonable amount of associated expenditures.

Syndromic surveillance for West Nile virus using raptors in rehabilitation

BackgroundWildlife rehabilitation centers routinely gather health-related data from diverse species. Their capability to signal the occurrence of emerging pathogens and improve traditional surveillance remains largely unexplored. This paper assessed the utility for syndromic surveillance of raptors admitted to The Raptor Center (TRC) to signal circulation of West Nile Virus (WNV) in Minnesota between 1990 and 2014. An exhaustive descriptive analysis using grouping time series structures and models of interrupted times series was conducted for indicator subsets.ResultsA total of 13,080 raptors were monitored. The most representative species were red-tailed hawks, great horned owls, Cooper’s hawks, American kestrels and bald eagles. Results indicated that temporal patterns of accessions at the TRC changed distinctively after the incursion of WNV in 2002. The frequency of hawks showing WNV-like signs increased almost 3 times during July and August, suggesting that monitoring of hawks admitted to TRC with WNV-like signs could serve as an indicator of WNV circulation. These findings were also supported by the results of laboratory diagnosis.ConclusionsThis study demonstrates that monitoring of data routinely collected by wildlife rehabilitation centers has the potential to signal the spread of pathogens that may affect wild, domestic animals and humans, thus supporting the early detection of disease incursions in a region and monitoring of disease trends. Ultimately, data collected in rehabilitation centers may provide insights to efficiently allocate financial and human resources on disease prevention and surveillance.

Recent invasion of European red foxes (Vulpes vulpes) on to Fraser Island (K'gari) and South Stradbroke Island

AbstractInvasive predators are globally significant drivers of threatened fauna population decline and extinction, and the early detection of new incursions is critical to the chances of successful predator eradication and fauna conservation. Here, we provide evidence of the recent invasion of European red foxes (Vulpes vulpes) on to two large and internationally significant islands off the southeast coast of Queensland, Australia – Fraser Island (K'gari) and South Stradbroke Island. From camera trap footage collected on Fraser Island since 2009, foxes have now been observed on seven different occasions between 2012 and 2016. Two scats collected on South Stradbroke Island in 2013 and 2014 tested positive for fox DNA (and negative for Canis spp. DNA), with fox presence confirmed by subsequent camera trap footage in 2016. These data confirm the recent incursion of foxes on to these islands and suggest that small populations now exist there. Fraser Island and South Stradbroke Island represent key RAMSAR wetland areas of refuge for populations of multiple threatened fauna that have never been previously been exposed to foxes. Fox impacts on these fauna can only be expected to increase without management intervention to eradicate them before they become widespread.

Comparison of alternatives to passive surveillance to detect foot and mouth disease incursions in Victoria, Australia

This study aimed to evaluate strategies to enhance the early detection of foot and mouth disease incursions in Australia. Two strategies were considered. First, improving the performance of the current passive surveillance system. Second, supplementing the current passive system with active surveillance strategies based on testing animals at saleyards or through bulk milk testing of dairy herds. Simulation modelling estimated the impact of producer education and awareness by either increasing the daily probability that a farmer will report the presence of diseased animals or by reducing the proportion of the herd showing clinical signs required to trigger a disease report. Both increasing the probability of reporting and reducing the proportion of animals showing clinical signs resulted in incremental decreases in the time to detection, the size and the duration of the outbreak. A gold standard system in which all producers reported the presence of disease once 10% of the herd showed clinical signs reduced the median time to detection of the outbreak from 20 to 15days, the duration of the subsequent outbreak from 53 to 42days and the number of infected farms from 46 to 32. Bulk milk testing reduced the median time to detection by two days and the number of infected farms by six but had no impact on the duration of the outbreak. Screening of animals at saleyards provided no improvement over the current passive surveillance system alone while having significant resource issues. It is concluded that the most effective way to achieve early detection of incursions of foot and mouth disease into Victoria, Australia is to invest in improving producer reporting.

Web and Mobile Phone Based Rabies Surveillance System for Humans and Animals in Kilosa District, Tanzania

Rabies has continued to claim human life despite different efforts to controls its transmission cycles between humans and domestic dogs. New developments in ICT have provided an opportunity for increased possibilities for community involvement in rabies surveillance. The main objective of this study was to investigate on approaches and practices to improve the communication of rabies surveillance information at different levels. Specifically, a study was carried to establish the significance of applying human sensor web system. Human sensor web has a potential of strengthening rabies surveillance system and serves as applied research tools for investigating strategic spatially targeted control activities, identifying areas most at risk and early detection of rabies incursions. Web and mobile based rabies surveillance system was developed and piloted as a support tool for the detection, surveillance and control of rabies. Wide application of the developed system will pave way for effective and efficient country-wide sharing of rabies surveillance information.

Raspberry Ketone Trifluoroacetate, a New Attractant for the Queensland Fruit Fly, Bactrocera Tryoni (Froggatt).

Queensland fruit fly, Bactrocera tryoni (Q-fly), is a major pest of horticultural crops in eastern Australia. Lures that attract male Q-fly are important for detection of incursions and outbreaks, monitoring of populations, and control by mass trapping and male annihilation. Cuelure, an analog of naturally occurring raspberry ketone, is the standard Q-fly lure, but it has limited efficacy compared with lures that are available for some other fruit flies such as methyl eugenol for B. dorsalis. Melolure is a more recently developed raspberry ketone analog that has shown better attraction than cuelure in some field studies but not in others. A novel fluorinated analog of raspberry ketone, raspberry ketone trifluoroacetate (RKTA), has been developed as a potential improvement on cuelure and melolure. RKTA placed on laboratory cages containing 2-week-old Q-flies elicited strong behavioral responses from males. Quantification of Q-fly responses in these cages, using digital images to estimate numbers of flies aggregated near different lures, showed RKTA attracted and arrested significantly more flies than did cuelure or melolure. RKTA shows good potential as a new lure for improved surveillance and control of Q-fly.