Individual-based modelling of moth dispersal to improve biosecurity incursion response

1. Some biosecurity systems aimed at reducing the impacts of invasive alien species that employ sentinel trapping systems to detect the presence of unwanted organisms. Once detected, the next challenge is to locate the source population of the invasive species. Tools that can direct search efforts towards the most likely sources of a trapped invasive alien species can improve the chance of rapidly delimiting and eradicating the local population and may help to identify the original introduction pathway. Ground-based detection and delimitation surveys can be very expensive, and methods to focus search efforts to those areas most likely to contain the target organisms can make these efforts more effective and efficient. 2. An individual-based semi-mechanistic model was developed to simulate the spatio-temporal dispersal patterns of an invasive moth. The model combines appetitive and pheromone anemotaxis behaviours in response towind, temperature and pheromone conditions. The modelwas trained using data from a series ofmark-release-recapture experiments on painted applemoth Teia anartoides. 3. The model was used to create hindcast simulations by reversing the time course of environmental conditions. The ability of the model to encompass the release location was evaluated using individual trap locations as starting points for the hindcast simulations. 4. The hindcast modelling generated a pattern of moth flights that successfully encompassed the origin from 86%of trap locations, representing 95%of the 1464 recaptures observed in the mark- release-recapture experiments. 5. Comparing the guided search area defined using the hindcast model with the area of a simple point-diffusion search strategy revealed an optimized search strategy that combined searching a circle of 1 km radius around the trap followed by the area indicated by hindcast model predictions. 6. Synthesis and applications. Incorporating this novel moth dispersal model into biosecurity sentinel systems will allow incursion managers to direct search effort for the proximal source of the incursion towards those areas most likely to contain a local infestation. Such targeted effort should reduce the costs and time taken to detect the proximal source of an incursion. (Résumé d'auteur

Distribution and ecology of Garidella nigellastrum L. : application to its conservation

Garidella nigellastrum L., espèce messicole rare et protégée des champs de céréales est confrontée à un déclin récent et à un isolement des populations spontanées. Le Parc du Luberon et le Conservatoire d’espaces naturels de PACA (CEN PACA, ex-CEEP), en partenariat avec l’Institut méditerranéen de biodiversité et d’écologie marine et continentale (IMBE, ex-IMEP), veulent agir sur sa conservation en multipliant les populations in situ. Le succès de l’introduction dépend de la diversité génétique potentiellement contenue dans la banque de graines et des traits de vie de l’espèce, mais également de la prise en compte de sa dynamique spatiale. Une carte de distribution a été réalisée à partir de la littérature et des herbiers pour la région Provence-Alpes-Côte d’Azur (PACA). L’utilisation d’une technique de modélisation bioclimatique montre que la majeure partie du territoire du Parc du Luberon et plus généralement l’ouest de la Provence, apparaît favorable à sa présence ou à sa réinstallation. G. nigellastrum ne forme pas de banque de graines persistante. Dans un échantillonnage systématique de 29 kg de sol, seules 4 graines ont été retrouvées. Ceci peut être relié à une instabilité au niveau de la population et à de nombreuses extinctions en France. L’étude du cortège associé à cette espèce, à l’échelle intrapopulationnelle, n’a pas révélé de différences floristiques fortes reliées à son abondance. Nos résultats permettent de favoriser le transfert de graines comme technique de (re-)introduction. Cependant, les prélèvements doivent être limités afin de ne pas mettre en péril les deux dernières populations françaises,Garidella nigellastrum L., a rare and protected annual plant of cereal fields is faced with a recent decline and isolation of large spontaneous populations. The Parc du Luberon and the CEN PACA, in partnership with the IMBE, want to act on its conservation by multiplying in situ populations. Since the successful introduction of an annual plants depends on many factors such as genetic diversity, existence of a persistent seed bank, reproductive and vegetative traits of the species and our knowledge about its history and distribution. A distribution map was compiled from literature and herbarium accounts for the PACA region, France. We used bioclimatic modeling techniques to produce a map of suitable areas for G. nigellastrum populations. It appears that the majority of the Parc du Luberon as well as large parts of Western Provence, are suitable for the presence or its relocation. G. nigellastrum does not form a persistent seed bank in the soil. In a systematic sample of 29 kg of soil, only four dead seeds have been found. This may be related to its instability on the population level and the high number of recent extinction events for populations in France. The study of the flora associated with this species at the intra-population scale has not revealed significant floristic differences related to its abundance. Our findings suggest that the transfer of wheat seeding material can be a promising tool for (re-)introductions. However, seed sampling must be limited in order not to jeopardize the last two populations in the wild

WOODIV, a database of occurrences, functional traits, and phylogenetic data for all Euro-Mediterranean trees

Trees play a key role in the structure and function of many ecosystems worldwide. In the Mediterranean Basin, forests cover approximately 22% of the total land area hosting a large number of endemics (46 species). Despite its particularities and vulnerability, the biodiversity of Mediterranean trees is not well known at the taxonomic, spatial, functional, and genetic levels required for conservation applications. The WOODIV database fills this gap by providing reliable occurrences, four functional traits (plant height, seed mass, wood density, and specific leaf area), and sequences from three DNA-regions (rbcL, matK, and trnH-psbA), together with modelled occurrences and a phylogeny for all 210 Euro-Mediterranean tree species. We compiled, homogenized, and verified occurrence data from sparse datasets and collated them on an INSPIRE-compliant 10 × 10 km grid. We also gathered functional trait and genetic data, filling existing gaps where possible. The WOODIV database can benefit macroecological studies in the fields of conservation, biogeography, and community ecology.Labex OT-Med n ANR-11-LABX-006

The effects of climate data precision on fitting and projecting species niche models

International audienc

Unexpected response of the seagrass Posidonia oceanica to a warm-water episode in the North Western Mediterranean Sea

International audienceThe response of Posidonia oceanica (Linnaeus) Delile to the warm-water episode of summer 1999 was studied by means of the technique of lepidochronology. Study sites include three sites affected by the mass mortality event of benthic invertebrates and one not affected. The results showed a significant decline in some parameters (number of leaves and/or rhizome growth) for the three sites affected by the mass mortality event for the year following the warm-water episode (1999-2000). A similar decline was not observed for the unaffected site. The fact that high temperatures could have a negative impact on deep Posidonia oceanica near its cold limit of distribution is an unexpected result. To cite this article: N

The current and future potential geographical distribution of the oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae)

International audienceThe oriental fruit fly, Bactrocera dorsalis (Hendel), is a major pest throughoutSouth East Asia and in a number of Pacific Islands. As a result of their widespreaddistribution, pest status, invasive ability and potential impact on market access,B. dorsalis and many other fruit fly species are considered major threats to manycountries. CLIMEXTM was used to model the potential global distribution ofB. dorsalis under current and future climate scenarios. Under current climaticconditions, its projected potential distribution includes much of the tropics andsubtropics and extends into warm temperate areas such as southern MediterraneanEurope. The model projects optimal climatic conditions for B. dorsalis in thesouth-eastern USA, where the principle range-limiting factor is likely to be coldstress. As a result of climate change, the potential global range for B. dorsalis isprojected to extend further polewards as cold stress boundaries recede. However,the potential range contracts in areas where precipitation is projected to decreasesubstantially. The significant increases in the potential distribution of B. dorsalisprojected under the climate change scenarios suggest that the World TradeOrganization should allow biosecurity authorities to consider the effects of climatechange when undertaking pest risk assessments. One of the most significant areasof uncertainty in climate change concerns the greenhouse gas emissions scenarios.Results are provided that span the range of standard Intergovernmental Panel onClimate Change scenarios. The impact on the projected distribution of B. dorsalis isstriking, but affects the relative abundance of the fly within the total suitable rangemore than the total area of climatically suitable habitat

Brown bear den characteristics and selection in eastern Transylvania, Romania

International audienceDens are important for species that need to survive and reproduce during harsh winters. Brown bears (Ursus arctos) in Romania, listed by the European Union as a population of concern, use dens for several months each year. To date, few quantitative assessments of denning habitat have been carried out for this population or others in Europe. In 2008-2013 and 2015-2017, we used local knowledge and telemetry data from brown bears fitted with GPS collars to identify 115 winter dens and eight open ground nests used by bears in eastern Transylvania, Romania. We located most dens in mountainous areas (64%) and fewer in foothills (36%). Den entrances in mountainous areas were significantly narrower than entrances in foothills, likely due to the need for reduced thermal loss during more severe winters at higher elevations. We selected seven habitat characteristics (abiotic and biotic) and human-related covariates associated with known locations of dens and open nests to identify potential brown bear denning habitat using maximum entropy modeling. We found that terrain ruggedness was the single most important factor when predicting bear denning habitat. The habitat map derived from this study can be used in the future to safeguard bear denning areas from potential human disturbances

Species Distribution 2.0: An Accurate Time- and Cost-Effective Method of Prospection Using Street View Imagery

International audienceSpecies occurrence data provide crucial information for biodiversity studies in the current context of global environmental changes. Such studies often rely on a limited number of occurrence data collected in the field and on pseudo-absences arbitrarily chosen within the study area, which reduces the value of these studies. To overcome this issue, we propose an alternative method of prospection using geo-located street view imagery (SVI). Following a standardised protocol of virtual prospection using both vertical (aerial photographs) and horizontal (SVI) perceptions, we have surveyed 1097 randomly selected cells across Spain (0.1x0.1 degree, i.e. 20% of Spain) for the presence of Arundo donax L. (Poaceae). In total we have detected A. donax in 345 cells, thus substantially expanding beyond the now two-centuries-old field-derived record, which described A. donax only 216 cells. Among the field occurrence cells, 81.1% were confirmed by SVI prospection to be consistent with species presence. In addition, we recorded, by SVI prospection, 752 absences, i.e. cells where A. donax was considered absent. We have also compared the outcomes of climatic niche modeling based on SVI data against those based on field data. Using generalized linear models fitted with bioclimatic predictors, we have found SVI data to provide far more compelling results in terms of niche modeling than does field data as classically used in SDM. This original, cost-and time-effective method provides the means to accurately locate highly visible taxa, reinforce absence data, and predict species distribution without long and expensive in situ prospection. At this time, the majority of available SVI data is restricted to human-disturbed environments that have road networks. However, SVI is becoming increasingly available in natural areas, which means the technique has considerable potential to become an important factor in future biodiversity studies

Does coverage matter at mesoscale within a Posidonia oceanica seagrass meadow?

International audienc