Invasive species are ecologically and economically highly destructive. Early detection of these organisms and tracking of their spread after establishment is crucial to mitigating their impact. However, trained experts cannot monitor for the hundreds of invasive species in all potential establishment and spread areas. Monitoring can be increased through citizen science programs that encourage reporting sightings of invasive species through online platforms like websites and phone apps. Some of these efforts are explicitly about invasive species whereas others are broad biodiversity programs. Understanding the traits of organisms that people report in these websites and apps may help outreach coordinators better allocate their resources towards encouraging the use of the platforms most likely to be effective for their organisms of focus. We tested if physical, behavioral, and natural history traits of invasive species influence if and on which platforms organisms are reported. We collected 60,752 reports by the general public of invasive species (20 invertebrates, 14 vertebrates, and 29 plants) east of the Mississippi in the United States from 2008-2018 from the two most widely used citizen science biodiversity databases (EDDMaps and iNaturalist) and categorized them with 18 classes of traits (e.g. habitat, “flashy” appearance, size, etc.).
Results/Conclusions
We identified traits that impact reports of invasive species by the general public. For example, we found that more invasive species that are terrestrial, behave in a “flashy” manner, or are plants were reported but did not find any relationships between the number of reports and “flashy” appearance, density, or activity time. All of the traits we examined were significantly related to number of reports on the two platforms. Of particular note, invertebrates and vertebrates were reported significantly more on iNaturalist but plants were reported equally on iNaturalist and EDDMaps, aquatic organisms were reported significantly more on EDDMaps than iNaturalist but terrestrial organisms were reported equally frequently on both platforms, and crepuscular and diurnal organisms were reported more frequently on iNaturalist but nocturnal organisms were reported more frequently on EDDMaps. Our results may help invasive species educators tailor their reporting messaging according to the characteristics of their organisms of focus. Our results may also help make predictions about the utility of recruiting the general public for help monitoring for future invaders based on their physical, behavioral, and natural history traits.