Estimating the number of whales entering trade using DNA profiling and capture-recapture analysis of market products

Surveys of commercial markets combined with molecular taxonomy (i.e. molecular monitoring) provide a means to detect products from illegal, unregulated and/or unreported (IUU) exploitation, including the sale of fisheries bycatch and wild meat (bushmeat). Capture-recapture analyses of market products using DNA profiling have the potential to estimate the total number of individuals entering the market. However, these analyses are not directly analogous to those of living individuals because a 'market individual' does not die suddenly but, instead, remains available for a time in decreasing quantities, rather like the exponential decay of a radioactive isotope. Here we use mitochondrial DNA (mtDNA) sequences and microsatellite genotypes to individually identify products from North Pacific minke whales (Balaenoptera acutorostrata ssp.) purchased in 12 surveys of markets in the Republic of (South) Korea from 1999 to 2003. By applying a novel capture-recapture model with a decay rate parameter to the 205 unique DNA profiles found among 289 products, we estimated that the total number of whales entering trade across the five-year survey period was 827 (SE, 164; CV, 0.20) and that the average 'half-life' of products from an individual whale on the market was 1.82 months (SE, 0.24; CV, 0.13). Our estimate of whales in trade (reflecting the true numbers killed) was significantly greater than the officially reported bycatch of 458 whales for this period. This unregulated exploitation has serious implications for the survival of this genetically distinct coastal population. Although our capture-recapture model was developed for specific application to the Korean whale-meat markets, the exponential decay function could be modified to improve the estimates of trade in other wildmeat or fisheries markets or abundance of living populations by noninvasive genotyping.     

Incomplete reporting of whale, dolphin and porpoise 'bycatch' revealed by molecular monitoring of Korean markets

We report the results of molecular monitoring of 'whalemeat' markets in the Republic of (South) Korea based on nine systematic surveys from February 2003 to February 2005. As Korea has no programme of commercial or scientific whaling and there is a closure on the hunting of dolphins and porpoises, the only legal source of these products was assumed to be incidental fisheries mortalities ('bycatch') as reported by the government to the International Whaling Commission. Species identification of 357 products using mitochondrial DNA control region or cytochrome b sequences and the web-based programme DNA-surveillance revealed three species of baleen whales (North Pacific minke, common form Bryde's and humpback), three species of beaked whales (Cuvier's, Stejneger's and Blainville's), seven species of dolphins (short-finned pilot, false killer and killer whales; Risso's, bottlenose, common and Pacific white-sided dolphins) and two species of porpoises (harbour and finless). Comparison of market products with official records revealed a number of discrepancies. Of the eight species identified on the markets in 2003, three were not reported in official records for that year. Of the 11 species identified in 2004, five were not reported as bycatch, although one species, a humpback whale, was reported as 'stranded'. We also found significant inconsistencies in the expected frequencies of products from most species, including a large over-representation of finless porpoises and false killer whales. We suggest ways in which market surveys could be improved to provide better information on the magnitude of fisheries bycatch and other illegal, unregulated and unreported (IUU) exploitation of wildlife.     

Forensic genetic identification of sturgeon caviars traveling in world trade

Caviar is among the world’s most valuable wildlife products. Exploitation of sturgeon and paddlefish for the caviar trade has severely reduced abundance, and harvest of most species is regulated under CITES. International trade requires that importing nations verify the species source of caviars they receive; the US domestic trade has no such requirement. We report the results of forensic species identifications of US caviar imports from 1998 to 2008 and of US domestic market caviars from 1997 to 1998. Twelve species were identified overall and species origins were mislabeled three times as often among US domestic market caviars (14.7 %) as among imports (4.9 %). Industry practices associated with the re-packaging of caviars for domestic markets and re-export from intermediate countries have created opportunities for the co-mingling of legitimate caviars with those from illegal, unreported and unregulated sources.     

Back to the future: natural history and the way forward in modern fungal ecology

The growing power and increasing availability of molecular tools for identifying fungi in environmental samples has revolutionized the way that fungal ecologists work. As a result, more people from around the globe have jumped into the fungal community sequencing endeavor. Paradoxically, as these extensive datasets accumulate we are often at a loss for interpretation due to the lack of basic autecology and natural history information for most fungi. As a result we are in danger of learning less and about more and more. I suggest that one way forward in fungal ecology is through a modern version of fungal natural history, with a focus on holistic understanding of individual species and ecosystems, but driven by modern genomic and molecular tools. By combining the extensive data generated through environmental sequencing with an intensive, molecular-based natural history we can create a synergy that will propel fungal ecology forward.     

Global-scale genetic identification of hammerhead sharks: Application to assessment of the international fin trade and law enforcement

The future status of sharks is an issue of widespread conservation concern due to declines in many species in the face of high levels of exploitation to satisfy market demands for products, especially fins. Substantial declines in the large-bodied hammerhead sharks, Sphyrna lewini, S. mokarran and S. zygaena, even in regions where some management occurs, indicate that informed conservation measures are warranted for these circumglobally distributed species. Despite the importance of assessing shark catch and trade on a species-specific basis to detect potential overexploitation of individual species, achieving this goal for hammerheads has proven elusive due to difficulties in identification of their products. Here, we present the development and application of a diagnostic, streamlined, five-primer multiplex polymerase chain reaction assay utilizing species-specific primers based on nuclear ribosomal ITS2 for the three hammerhead species throughout their global distribution. Application of this assay to investigations of the fin market confirmed the presence of hammerhead fins in the international trade. A study of the world’s largest fin market in Hong Kong revealed a high concordance between specific Chinese-name trade categories and fins from these three species (“Bai Chun” with S. lewini, “Gui Chun” with S. zygaena and “Gu Pian” with S.␣mokarran), and clear species preferences. This concordance information allows the use of market records for monitoring species-specific trends in trade and exploitation rates. The assay is also proving useful for identification of shark body parts in U.S. fisheries law-enforcement activities. Screening of morphologically identified “ S. lewini” from globally distributed areas using this assay with subsequent whole ITS2 sequencing suggests a cryptic species closely related to S. lewini occurs off the SE USA coast.     

Wild orchid tuber collection in Iran: a wake-up call for conservation

Wild orchids are traditionally harvested as Salep and used in traditional medicine and ice-cream production in Iran. Recently however, illegal harvest of wild orchids for export appears to have grown. This study aimed to: (1) determine the diversity of harvested wild orchid species and their collection sites in Iran; and (2) study the current harvest status and trade chain and volume to estimate the total orchid plant extraction from natural populations. Field surveys of collectors and market surveys of traders were conducted to establish the diversity of collected species, to identify harvest hotspots, and to document harvesting and trade volumes. Sixteen species and subspecies from 7 genera of Orchidaceae are collected for their tubers. Based on estimates from the 2013 April to June harvest season more than 24.5 tons of fresh tubers were collected from three districts in Golestan province alone. It is estimated that this amount of tuber requires the lethal destructive harvesting of 5.5 –6.1 million orchids, with a market value of 320,000 USD. In the Tehran Bazar Salep trade during May–July 2013 was 1.9 tons of dried tubers, with estimated retail value of 310,000 USD. Current orchid collection practices in Iran, which have soared in recent years due to international demand, do not seem sustainable as all tubers are collected destructively. To preserve orchid populations, in the longterm, establishment of specific Orchid Conservation Areas and introduction of sustainable production practices, could alleviate harvesting pressure. In the midterm, development of a DNA barcoding-based molecular identification system could help to monitor and control illegal trade. In the near term, effective implementation of collection bans in excessively harvested areas and strengthening of current regulations are necessary to avoid the catastrophic effects of harvesting on orchid populations, as has been observed in Turkey.     

Predicted decline of protected whales based on molecular genetic monitoring of Japanese and Korean markets

We present a two-tiered analysis of molecular genetic variation in order to determine the origins of whale' products purchased from retail markets in Japan and the Republic of (South) Korea during 1993-1999. This approach combined phylogenetic analysis of mitochondrial DNA sequences for identification of protected species with a statistical comparison of intraspecific haplotype frequencies for distinguishing regional subpopulations or 'stocks' hunted for scientific research by the Japanese and killed incidentally in coastal fisheries by the Koreans. The phylogenetic identification of 655 products included eight species or subspecies of baleen whales, sperm whales, a pygmy sperm whale, two species of beaked whales, porpoises, killer whales and numerous species of dolphins as well as domestic sheep and horses. Six of the baleen whale species (the fin, sei, common-form and small-form Bryde's, blue or blue/fin hybrid, and humpback) and the sperm whale are protected by international agreements dating back to at least 1989 for all species and 1966 for some species. We compared the haplotype frequencies from the Japanese market sample to those reported from scientific hunting in the western North Pacific stock for products derived from the exploited North Pacific minke whale. The market sample differed significantly from the scientific catch (p < 0.001), showing a greater than expected frequency of haplotypes characteristic of the protected Sea of Japan stock. We used a 'mixed-stock' analysis and maximum-likelihood methods to estimate that 31% (95% confidence interval 19-43%) of the market for this species originated from the Sea of Japan stock. The source of these products was assumed to be undocumented 'incidental takes' from fisheries' by-catch, although we cannot exclude the possibility of illegal hunting or smuggling. The demographic impact of this undocumented exploitation was evaluated using the model of population dynamics adopted by the Scientific Committee of the International Whaling Commission. For the range of exploitation consistent with the market sample, this protected stock was predicted to decline towards extinction over the next few decades. These results confirmed the power of molecular methods in monitoring retail markets and pointed to the inadequacy of the current moratorium for ensuring the recovery of protected species. More importantly, the integration of genetic evidence with a model of population dynamics identified an urgent need for actions to limit undocumented exploitation of a 'protected' stock of whales.     

Characterization of the pelagic shark‐fin trade in north‐central Chile by genetic identification and trader surveys

Shark fins have become a highly valued commodity with the major Asian fin‐trade centres supplied from global sources, including Chile. With growing concerns about the resilience of shark populations to heavy fishing pressure, there is a need for better information on shark landings to aid management efforts. In the widespread absence of shark landing records especially by species, monitoring the fin trade has been proposed as a way to assess species exploitation levels. Here, the first species assessment of the Chilean shark‐fin trade was provided. The goals of this study were to (1) determine the species composition and relative species proportion of sharks utilized in the fin trade, (2) determine the relationship between fin trader market names and species and (3) assess trader accuracy in identifying shark fin species based on fin photographs. Fins were analysed from two different fin drying facilities (n = 654) (secaderos) and two fin‐storage warehouses (n = 251). In contrast to official government landing records that only document four species in the landings, molecular species identification of the fins demonstrated that at least 10 pelagic shark species are present in the north‐central Chilean shark fin trade: Alopias superciliosus, Alopias vulpinus, Carcharhinus obscurus, Galeorhinus galeus, Isurus oxyrinchus, Isurus paucus, Lamna nasus, Prionace glauca, Sphyrna lewini, Sphyrna zygaena. The species composition of the fins from the secaderos was P. glauca (83·9%), I. oxyrinchus (13·6%), L. nasus (1·7%) and A. superciliosus (0·2%). There was generally good agreement between market names and single shark species for the trade categories ‘Azulejo’, ‘Tiburon’, ‘Tintorera’, ‘Cola de zorro’ and ‘Martillo’. In contrast, the market category ‘Carcharhinus’ consisted of a mixture of at least five species. The molecular results also identified two species (S. lewini and I. paucus) not previously recorded in Chilean waters. The fin identification survey given to nine regional traders demonstrated that they were highly accurate in recognizing pictures of fins from P. glauca and I. oxyrinchus. The overall strong concordance between market categories and fins from single species and the trader accuracy in survey fin identification suggests that monitoring the Chilean fin trade by market names will provide a reasonably accurate picture of the volume of sharks landed by species.     

Wildlife Trade and Human Health in Lao PDR: An Assessment of the Zoonotic Disease Risk in Markets

Although the majority of emerging infectious diseases can be linked to wildlife sources, most pathogen spillover events to people could likely be avoided if transmission was better understood and practices adjusted to mitigate risk. Wildlife trade can facilitate zoonotic disease transmission and represents a threat to human health and economies in Asia, highlighted by the 2003 SARS coronavirus outbreak, where a Chinese wildlife market facilitated pathogen transmission. Additionally, wildlife trade poses a serious threat to biodiversity. Therefore, the combined impacts of Asian wildlife trade, sometimes termed bush meat trade, on public health and biodiversity need assessing. From 2010 to 2013, observational data were collected in Lao PDR from markets selling wildlife, including information on volume, form, species and price of wildlife; market biosafety and visitor origin. The potential for traded wildlife to host zoonotic diseases that pose a serious threat to human health was then evaluated at seven markets identified as having high volumes of trade. At the seven markets, during 21 observational surveys, 1,937 alive or fresh dead mammals (approximately 1,009 kg) were observed for sale, including mammals from 12 taxonomic families previously documented to be capable of hosting 36 zoonotic pathogens. In these seven markets, the combination of high wildlife volumes, high risk taxa for zoonoses and poor biosafety increases the potential for pathogen presence and transmission. To examine the potential conservation impact of trade in markets, we assessed the status of 33,752 animals observed during 375 visits to 93 markets, under the Lao PDR Wildlife and Aquatic Law. We observed 6,452 animals listed by Lao PDR as near extinct or threatened with extinction. The combined risks of wildlife trade in Lao PDR to human health and biodiversity highlight the need for a multi-sector approach to effectively protect public health, economic interests and biodiversity.     

Native seed trade of herbaceous species for restoration: a European policy perspective with global implications

With the need to meet ambitious restoration targets, an improved native seed sector for the production of herbaceous species with a practical and supportive policy framework is recognized. We evaluated the current “ready‐made” policy frameworks in Europe regarding the native seed supply of herbaceous species and found them to be, generally, unsatisfactory for both producers and users. Initially, such policies were designed for fodder seed and relate to distinctness, uniformity, and stability, traits that do not reflect the genetic heterogeneity of native species required for ecological restoration. Until recently, more suitable certification standards were designed to multiply fodder seed for preservation of the natural environment; however, due to the disparateness of the seed market in Europe, this policy is rarely practical and fails to encompass all herbaceous native species often resulting in unregulated seed sales. We recommend a new or adapted native seed policy constructed through a participatory or bottom‐up approach and supported through the formation of widely based trade associations. Such a policy could stimulate the native seed trade with concomitant impacts on the speed of improving ecosystem services.     

Collection and trade of wild-harvested orchids in Nepal

Background

Wild orchids are illegally harvested and traded in Nepal for use in local traditional medicine, horticulture, and international trade. This study aims to: 1) identify the diversity of species of wild orchids in trade in Nepal; 2) study the chain of commercialization from collector to client and/or export; 3) map traditional knowledge and medicinal use of orchids; and 4) integrate the collected data to propose a more sustainable approach to orchid conservation in Nepal.

Methods

Trade, species diversity, and traditional use of wild-harvested orchids were documented during field surveys of markets and through interviews. Trade volumes and approximate income were estimated based on surveys and current market prices. Orchid material samples were identified to species level using a combination of morphology and DNA barcoding.

Results

Orchid trade is a long tradition, and illegal export to China, India and Hong Kong is rife. Estimates show that 9.4 tons of wild orchids were illegally traded from the study sites during 2008/2009. A total of 60 species of wild orchids were reported to be used in traditional medicinal practices to cure at least 38 different ailments, including energizers, aphrodisiacs and treatments of burnt skin, fractured or dislocated bones, headaches, fever and wounds. DNA barcoding successfully identified orchid material to species level that remained sterile after culturing.

Conclusions

Collection of wild orchids was found to be widespread in Nepal, but illegal trade is threatening many species in the wild. Establishment of small-scale sustainable orchid breeding enterprises could be a valuable alternative for the production of medicinal orchids for local communities. Critically endangered species should be placed on CITES Appendix I to provide extra protection to those species. DNA barcoding is an effective method for species identification and monitoring of illegal cross-border trade.

     

Identification of aphid species (Hemiptera: Aphididae: Aphidinae) using a rapid polymerase chain reaction restriction fragment length polymorphism method based on the cytochrome oxidase subunit I gene

Abstract  The identification of immature aphids is often difficult or impossible. This can be a problem when there is a need for a rapid and accurate diagnosis of any aphid life stage, such as for quarantine inspections and horticultural surveys. A polymerase chain reaction restriction fragment length polymorphism technique is described on the mitochondrial cytochrome oxidase subunit I (COI) gene to develop a molecular identification key for immature aphids from Victoria, Australia. The restriction enzymes HpyCH4 IV, Dra I, Hinf I, Taq I and Ssp I characterised 26 haplotypes that corresponded to 25 aphid species commonly found in southern Australian aphid surveys, including the currant-lettuce aphid Nasonovia ribis-nigri (Mosley) that has recently invaded Australia, presumably from New Zealand. Overseas specimens of Aulacorthum solani (Kaltenbach) and N. ribis-nigri showed no significant sequence difference when compared with their Australian counterparts. The COI gene provides a useful marker for diagnostic aphid surveys.     

A novel multiplex PCR assay for the identification of Indian crocodiles

Illegal hunting has been a major threat for the survival of wildlife fauna, including the three crocodile species that India harbours: Crocodylus palustris, Crocodylus porosus and Gavialis gangeticus. Although law prevents trade on these species, illicit hunting for trade continues to threaten the survival of these endangered species; conservation strategies therefore require a rapid molecular identification technique for Indian crocodiles. A multiplex polymerase chain reaction (PCR) assay with species-specific primers, considered as one of the most effective molecular techniques, is described herein. The primers were designed to yield species-specific sized amplicons. The assay discriminates the three Indian crocodile species unambiguously within a short time period using only simple agarose gel electrophoresis. We recommend this multiplex PCR assay to be used in the identification of Indian crocodile species.     

Identification of the shark species Rhizoprionodon lalandii and R. porosus (Elasmobranchii, Carcharhinidae) by multiplex PCR and PCR-RFLP techniques

Rhizoprionodon lalandii and R. porosus are widely distributed along the Atlantic coast of the Americas, living close to coastal areas and therefore frequently captured by seaboard fisheries. However, morphological identification of species in this genus is very difficult, especially when sharks have their heads and fins removed, making information about fishing, trading, and the evaluation of fishery effects on species conservation very difficult. This study's main objective is to develop molecular tools to identify these species using multiplex polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism techniques. Both techniques result in good low-cost markers and may be very useful in future studies about the exploitation of these species.     

Species and hybrid identification of sturgeon caviar: a new molecular approach to detect illegal trade

Overexploitation of wild populations due to the high economic value of caviar has driven sturgeons to near extinction. The high prices commanded by caviar on world markets have made it a magnet for illegal and fraudulent caviar trade, often involving low‐value farmed caviar being sold as top‐quality caviar. We present a new molecular approach for the identification of pure sturgeon species and hybrids that are among the most commercialized species in Europe and North America. Our test is based on the discovery of species‐specific single nucleotide polymorphisms (SNPs) in the ribosomal protein S7, supplemented with the Vimentin gene and the mitochondrial D‐loop. Test validations performed in 702 specimens of target and nontarget sturgeon species demonstrated a 100% identification success for Acipenser naccarii, A. fulvescens, A. stellatus, A. sinensis and A. transmontanus. In addition to species identification, our approach allows the identification of Bester and AL hybrids, two of the most economically important hybrids in the world, with 80% and 100% success, respectively. Moreover, the approach has the potential to identify many other existing sturgeon hybrids. The development of a standardized sturgeon identification tool will directly benefit trade law enforcement, providing the tools to monitor and regulate the legal trade of caviar and protect sturgeon stocks from illicit producers and traders, hence contributing to safeguarding this group of heavily threatened species.     

Molecular taxonomic tools provide more accurate estimates of species richness at less cost than traditional morphology-based taxonomic practices in a vegetation survey

Vegetation surveys are conducted to obtain a catalogue of the plant species that occupy an area of interest, and are used to inform the decisions of policymakers about conservation, development, and remediation efforts. Currently, vegetation surveys rely on traditional morphology-based taxonomic practices to identify collected specimens. By implementing recent advances in molecular taxonomy, it may be possible to improve upon these methods and reduce the associated costs. In this study, we used both morphological and molecular taxonomic methods to sample 337 forest vegetation plots in northeastern Ontario, Canada. DNA barcoding—a molecular taxonomic tool—was used to identify specimens collected in the molecular taxonomic survey. The molecular taxonomic survey identified a mean of 12.4 species per plot and 202 species in total, whereas the morphological taxonomic survey identified a mean of 9.8 species per plot and 142 species in total; both surveys provided identical estimates of community similarity. The morphological taxonomic survey was 37 % more expensive than molecular taxonomic survey, owing largely to the increased time required in the field to collect specimens that flowered at different times. Our results indicate that molecular taxonomic tools are more cost-effective than traditional morphology-based taxonomic practices for species identification in vegetation surveys. Taxonomy underpins all conservation, and the implementation of molecular taxonomic tools for vegetation surveys has promise to lessen the consequences of the taxonomic impediment and increase the effectiveness of conservation efforts.     

Bushmeat and bycatch: the sum of the parts

In many developing countries, the killing of wild animals for commercial purposes (the bushmeat trade) is a significant factor in the reduction of biodiversity, and probably represents a major threat to the survival of many more populations than we know. This includes marine species such as cetaceans, sea turtles and sirenians ("marine bushmeat"), which are often neglected in the discussion of this issue. Estimating the impact of the bushmeat trade anywhere is problematic because even the most thorough visual surveys of meat markets cannot easily translate an observed quantity of butchered products into the number of animals killed. In this issue of Molecular Ecology, Baker et al. provide a powerful new tool for such assessments: molecular identification of commercially available products from a depleted population of minke whales in South Korea is combined with genotyping and novel capture-recapture methods to estimate not only the number of individuals taken, but also the persistence of the resulting products in the marketplace.     

Identification and characterization of Saccharomyces cerevisiae and Saccharomyces paradoxus strains isolated from Croatian vineyards

AIMS: The identification, differentiation and characterization of indigenous Saccharomyces sensu stricto strains isolated from Croatian vineyards and the evaluation of their oenological potential. METHODS AND RESULTS: A total of 47 Saccharomyces sensu stricto strains were isolated from Chardonnay grapes and identified by physiological and molecular genetic methods. By using the standard physiological and biochemical tests, six isolates were identified as Saccharomyces cerevisiae and 41 as Saccharomyces paradoxus. However, PCR-RFLP analyses of the internal transcribed spacer (ITS1) region of the 18S ribosomal DNA identified 12 of the isolates as S.cerevisiae and 35 as S. paradoxus. Fermentation trials in a grape juice medium showed that these isolates ferment vigorously at 18 degrees C and display tolerance to high levels of ethanol. None of these isolates appeared to produce either hydrogen sulphide or killer toxins. CONCLUSION: Saccharomyces paradoxus, possessing potentially important oenological characteristics, occurs in much higher numbers than S. cerevisiae in the indigenous population of Saccharomyces sensu stricto strains in Croatian vineyards. SIGNIFICANCE AND IMPACT OF THE STUDY: This study forms an essential step towards the preservation and exploitation of the hidden oenological potential of the untapped wealth of yeast biodiversity in the Croatian grape-growing regions. The results obtained demonstrate the value of using molecular genetic methods, such as PCR-RFLP analyses, in conjunction with the traditional taxonomic methods based on phenotypic characteristics in such ecotaxonomic surveys. The results also shed some light on the ecology and oenological potential of S.paradoxus, which is considered to be the natural parent species of the domesticated species of the Saccharomyces sensu stricto group.     

A trade-based method for modelling supply markets in consequential LCA exemplified with Portland cement and bananas

Purpose

This study proposes a method based on the analysis of trade networks over time for modelling the marginal supply of products in consequential life cycle assessment (LCA). It aims at increasing the geographical granularity of markets, accuracy of transport distances and modes and material losses during transit by creating country-specific markets, instead of region-based supply-origin markets as currently proposed by ecoinvent. It leads to a better consideration of the environmental weight of trade following a change in demand on a local market and may serve as an inspirational basis for future releases of consequential life cycle inventory (LCI) databases.

Methods

The method uses ecoinvent v.3.3 as a support LCI database and two distinct traded products: bananas and grey Portland cement. Each country involved in the trade of a said product has a corresponding market created in the LCI database. The behavior of market to a marginal change in internal demand is modelled after its marginal trading preferences: it can either affect local production, imports, exports or a mix of the first two. Markets are linked to one another based on the linear regression analysis of their historical trade relations. The inventories that follow an increase in demand of 1000 kg of bananas and grey Portland cement are calculated for each market involved in their trade and are environmentally characterized and compared to the generic region-based market datasets provided by ecoinvent to assess the gains in accuracy through a higher geographical granularity. Furthermore, the characterized inventories of the markets for bananas are compared to a parallel scenario where transport distances are kept to a minimum using the shortest path method. It isolates the environmental burden associated to the utility maximization of the demand.

Results and discussion

When comparing the characterized impacts of country-specific markets with the generic ecoinvent market datasets, disparities in results appear. They highlight the importance of transport induced by demand displacement and losses of material during transport, both being the consequences of the extent a given market decides to be supplied directly from producing markets at the margin. These are aspects that may go unaccounted for when using generic regional markets. Second, optimizing transport distances for each market decreases the environmental impacts for most categories by more than 70%.

Conclusions

This study shows there is a need for modelling and understanding market relations to more accurately define the role of trade, supply chain efficiency and import policies in LCA.

     

Disentangling Vector-Borne Transmission Networks: A Universal DNA Barcoding Method to Identify Vertebrate Hosts from Arthropod Bloodmeals

Emerging infectious diseases represent a challenge for global economies and public health. About one fourth of the last pandemics have been originated by the spread of vector-borne pathogens. In this sense, the advent of modern molecular techniques has enhanced our capabilities to understand vector-host interactions and disease ecology. However, host identification protocols have poorly profited of international DNA barcoding initiatives and/or have focused exclusively on a limited array of vector species. Therefore, ascertaining the potential afforded by DNA barcoding tools in other vector-host systems of human and veterinary importance would represent a major advance in tracking pathogen life cycles and hosts. Here, we show the applicability of a novel and efficient molecular method for the identification of the vertebrate host''s DNA contained in the midgut of blood-feeding arthropods. To this end, we designed a eukaryote-universal forward primer and a vertebrate-specific reverse primer to selectively amplify 758 base pairs (bp) of the vertebrate mitochondrial Cytochrome c Oxidase Subunit I (COI) gene. Our method was validated using both extensive sequence surveys from the public domain and Polymerase Chain Reaction (PCR) experiments carried out over specimens from different Classes of vertebrates (Mammalia, Aves, Reptilia and Amphibia) and invertebrate ectoparasites (Arachnida and Insecta). The analysis of mosquito, culicoid, phlebotomie, sucking bugs, and tick bloodmeals revealed up to 40 vertebrate hosts, including 23 avian, 16 mammalian and one reptilian species. Importantly, the inspection and analysis of direct sequencing electropherograms also assisted the resolving of mixed bloodmeals. We therefore provide a universal and high-throughput diagnostic tool for the study of the ecology of haematophagous invertebrates in relation to their vertebrate hosts. Such information is crucial to support the efficient management of initiatives aimed at reducing epidemiologic risks of arthropod vector-borne pathogens, a priority for public health.