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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Invasive Species and Pollinator Health » Research » Publications at this Location » Publication #398156
Research Project: Integrated Weed Management and Restoration Strategies to Protect Water Resources and Aquatic and Wetland Ecosystems of the Far Western U.S.

Location: Invasive Species and Pollinator Health

Title: What distribution models of alligator weed in its native and invaded ranges tell us about its invasion story and biological control

Author
item SÁNCHEZ-RESTREPO, ANDRÉS - Fuedei
item RECHE, VANINA - Universidad De La Plata
item CABRERA, NORA - Universidad De La Plata
item PAN, XIAOYUN - Fudan University
item Pratt, Paul
item SOSA, ALEJANDRO - Fuedei

Submitted to: Entomologia Experimentalis et Applicata
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/22/2023
Publication Date: 11/15/2023
Citation: Sánchez-Restrepo, A.F., Reche, V.A., Cabrera, N., Pan, X., Pratt, P.D., Sosa, A. 2023. What distribution models of alligator weed in its native and invaded ranges tell us about its invasion story and biological control. Entomologia Experimentalis et Applicata. 171(12):1009–1018. https://doi.org/10.1111/eea.13353.
DOI: https://doi.org/10.1111/eea.13353

Interpretive Summary: Ecological niche models of species occurrence have gained interest in biological control programs to improve efficiency, reduce risks, and to inform when and how control agents may be released and/or surveyed. Alligator weed, Alternanthera philoxeroides (Mart.) Griseb. (Amaranthaceae), is an amphibious aquatic plant native to southern South America that has invaded several countries around the world. In this study our aim was to quantify the current and model future alligator weed geographical distributions in its introduced range (USA, the country where biological control of the weed was first implemented), and its native range in South America. Additionally, we modeled current and potential distribution of its biological control agent Agasicles hygrophila Selman & Vogt (Coleoptera: Chrysomelidae) released in the USA in 1964, and other potential biological control agents including the flea beetles, Disonycha argentinensis Jacoby and Systena sp. A total of 19438 occurrence records of alligator weed, 253 for A. hygrophila, 48 for D. argentinesis, and 19 Systena sp. were compiled. Niche models predict future alligator weed distributions will expand, particularly in northern regions of South America. However, the models of flea beetles A. hygrophila, D. argentinensis and Systena sp., did not predict geographic range expansion; on the contrary, the future scenarios are similar to current distributions.

Technical Abstract: Ecological niche models of species occurrence have gained interest in biological control programs to improve efficiency, reduce risks, and to inform when and how control agents may be released and/or surveyed. Alligator weed, Alternanthera philoxeroides (Mart.) Griseb. (Amaranthaceae), is an amphibious aquatic plant native to southern South America that has invaded several countries around the world. In this study our aim was to quantify the current and model future alligator weed geographical distributions in its introduced range (USA, the country where biological control of the weed was first implemented), and its native range in South America. Additionally, we modeled current and potential distribution of its biological control agent Agasicles hygrophila Selman & Vogt (Coleoptera: Chrysomelidae) released in the USA in 1964, and other potential biological control agents including the flea beetles, Disonycha argentinensis Jacoby and Systena sp. A total of 19438 occurrence records of alligator weed, 253 for A. hygrophila, 48 for D. argentinesis, and 19 Systena sp. were compiled. Niche models predict future alligator weed distributions will expand, particularly in northern regions of South America. However, the models of flea beetles A. hygrophila, D. argentinensis and Systena sp., did not predict geographic range expansion; on the contrary, the future scenarios are similar to current distributions.