Search publications, data, projects and authors
Reunion overseas: introduced wild boars and cultivated orange trees interact in the Brazilian Atlantic Forest




[EN] Introduction: Little is known concerning novel interactions between species that typically interact in their native range but, as a consequence of human activity, are also interacting out of their original distribution under new ecological conditions. Objective: We investigate the interaction between the orange tree and wild boar, both of which share Asian origins and have been introduced to the Americas (i.e. the overseas). Methods: Specifically, we assessed whether i) wild boars consume orange (Citrus sinensis) fruits and seeds in orchards adjacent to a remnant of the Atlantic Forest of Brazil, ii) the orange seeds are viable after passing through boar's digestive tract and iii) whether the orange tree may naturalise in the forest remnant assisted by wild boars. Results: Our camera surveys indicated that wild boar was by far the most frequent consumer of orange fruits (40.5 % of camera trap-days). A considerable proportion of sown orange seeds extracted from fresh boar feces emerged seedlings (27.8 %, N = 386) under controlled greenhouse conditions. Further, 37.6 % of sown seeds (N = 500) in the forest remnant emerged seedlings in July 2015; however, after similar to 4 years (March 2019) only 9 seedlings survived (i.e. 4.8 %, N = 188). Finally, 52 sweet orange seedlings were found during surveys within the forest remnant which is intensively used by wild boars. This study indicates a high potential of boars to act as effective seed dispersers of the sweet orange. However, harsh competition with native vegetation and the incidence of lethal diseases, which quickly kill sweet orange trees under non-agricultural conditions, could seriously limit orange tree establishment in the forest. Conclusions: Our results have important implications not only because the wild boar could be a vector of potential invasive species, but also because they disperse seeds of some native species (e.g. the queen palm, Syagrus romanzofiana) in defaunated forests, where large native seed dispersers are missing; thus, wild boars could exert critical ecological functions lost due to human activity. We sincerely thank A. Tachibana for allowing us to work at Fazenda Cambuhy Agricola and to his staff for helping to perform our field experiments. We thank Fundecitrus for funding and technical support. Eugene Schupp and three anonymous reviewers provided numerous comments and suggestions which greatly improved an earlier draft. JMF was funded by a Portuguese FCT grant (IF/00728/2013). Peris, JE.; Malara, TM.; Borges, R.; Falconi, JR.; Peña, L.; Fedriani, JM. (2019). Reunion overseas: introduced wild boars and cultivated orange trees interact in the Brazilian Atlantic Forest. Revista de Biología Tropical. International Journal of Tropical Biology and Conservation (Online). 67(4):901-912. https://doi.org/10.15517/RBT.V67I4.35862

Report a bug

Under construction

We're in Beta!

The GoTriple platform is still in Beta and we keep adding new features everyday. Check the project's website to see what's new and subscribe to our Mailing List.