Browsing by Author "Roy, Helen E."

Now showing 1 - 6 of 6
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    A Vision for Global Biodiversity Monitoring With Citizen Science
    (2018) Pocock, Michael J. O.; Chandler, Mark; Bonney, Rick; Thornhill, Ian; Albin, Anna; August, Tom; Bachman, Steven; Brown, Peter M. J.; Fernandes Cunha, Davi Gasparini; Grez, Audrey; Jackson, Colin; Peters, Monica; Rabarijaon, Narindra Romer; Roy, Helen E.; Zaviezo Palacios, Tania; Danielsen, Finn
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    Citizen Science and Phytosanitary Surveillance Systems Are Complementary Tools to Follow the Invasion of Harmonia axyridis
    (2023) Grez, Audrey A.; Zaviezo Palacios, Tania; Orellana, Ignacio; Pino, Luna; Roy, Helen E.; Torres, Fernando; Rebolledo, Claudia
    Citizen science is a valuable tool for early detection, distribution, and spread of invasive alien species (IAS). Nevertheless, citizen science initiatives have several potential biases and may be complemented with long-term structured monitoring schemes. We analyzed the spatial-temporal dynamics of the invasion of Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Chile, based upon two citizen sciences databases (WEB and INAT) and one structured monitoring (SAG). We collected 8638 H. axyridis occurrences between 2009 and 2020. WEB had a higher number of records than SAG and INAT, and in all databases, the number of records has increased over time. The three databases showed that the invasion started in central Chile and then spread toward the north and south. The WEB and SAG recorded occurrences in the extreme north and south, whereas INAT concentrated all the occurrences in a more limited area, included in WEB and SAG. Both citizen science initiatives concentrated their records in areas of high human populations whereas SAG records had a more even distribution across regions. At 2020, WEB accounted for 55%, SAG 54%, and INAT 8% of the total area accumulated with H. axyridis, with only 16% of area shared among databases. WEB and INAT obtained most of their records in urban and industrial land cover types, while SAG records were more evenly represented in different land cover types. Our results confirm that combined methods, including citizen science initiatives, national surveillance system, and localized samplings, complement each other in providing knowledge to understand the patterns, processes, and consequences of this invasion.
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    Predators and parasitoids of the harlequin ladybird, harmonia axyridis, in its native range and invaded areas
    (2018) Ceryngier, Piotr; Nedvěd, Oldřich; Grez, Audrey A.; Riddick, Eric W.; Roy, Helen E.; San Martin, Gilles; Steenberg, Tove; Veselý, Petr; Zaviezo Palacios, Tania; Zúñiga Reinoso, Álvaro; Haelewaters, Danny
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    Rapid spread of Harmonia axyridis in Chile and its effects on local coccinellid biodiversity
    (2016) Grez, Audrey A.; Zaviezo Palacios, Tania; Roy, Helen E.; Brown, Peter M. J.; Bizama, Gustavo
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    Scientific and Normative Foundations for the Valuation of Alien-Species Impacts: Thirteen Core Principles
    (2017) Essl, Franz; Hulme Philip E.; Jeschke, Jonathan M.; Keller, Reuben; Pysek, Petr.; Richardson, David M.; Saul, Wolf Christian; Bacher, Sven; Dullinger, Stefan; Estevez Weinstein, Rodrigo Antonio; Kueffer, Christoph; Roy, Helen E.; Seebens, Hanno; Rabitsch, Wolfgang
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    The harlequin ladybird, Harmonia axyridis : global perspectives on invasion history and ecology
    (2016) Roy, Helen E.; Brown, Peter M. J.; Adriaens, Tim; Berkvens, Nick; Borges, Isabel; Clusella-Trullas, Susana; Comont, Richard F.; De Clercq, Patrick; Eschen, René; Zaviezo Palacios, Tania