What we tweet about invasive species: Expanding discourse on Japanese knotweed

Background/Question/Methods

Understanding public perceptions of invasive species is important in structuring effective management plans, ensuring adequate conservation funding, and overall cultural control of invasive species. Experts in invasive species may provide education, but public discourse stemming from education and personal lived experiences with these invasive species ultimately determines public perceptions. Effective monitoring of public perceptions and discourse can come from social media. The goal of this study was to dissect the discourse surrounding invasive species in general by using discourse on Japanese knotweed as a particular example to highlight the domains in which society talks about invasive species.Over the summer of 2020, about 3,500 tweets mentioning “knotweed“ were scraped from twitter. These tweets were first cleaned to remove punctuation and meaningless words, and word counts determined the most common words in the dataset. Then, sentiment analysis was run using the NRC sentiment lexicon to assign scores to the data set for different emotional categories (e.g. fear, positive, anger etc). Each tweet was then analyzed for the use of metaphor within each tweet, and thematic analysis coded each tweet into a variety of groups based on how the tweeter engaged in discourse about the plant.

Results/Conclusions

Sentiment Analysis showed that tweets about knotweed are generally negative. There were also differences between original tweets and retweeted tweets in sentiment: with higher ratings for anger and fear in the retweets when compared to positive words. The thematic analysis showed the expansion of dialogue about introduced species into new domains, including active discussions about human wellness and nature appreciation. Tweeters were discussing knotweed in domains completely unrelated to invasive species, often using it as a metaphor for other societal issues that arise quickly and are difficult to manage. This metaphorical domain also extended into xenophobic discourse, with introduced plants being used to justify the exclusion of minorities. Expansion of talk about knotweed focusing on appreciation of the plant and its uses shows a societal desire to move past a strict discourse of eradication and towards management that maximizes societal benefit. The use of invasive plants in xenophobic discourse highlights how negative language used to educate the public can be amplified in societal discourse to be ultimately harmful to not just effective management, but also to minority groups. Future work expands analysis to the full twitter repository to look for temporal and species level trends in invasive species discourse.