Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

What are we talking about? Sika deer (Cervus nippon): a bibliometric network analysis.

Abstract

The introduction of alien species represents the second most dramatic cause of biodiversity loss all over the world as they may negatively affect the genetic diversity of native species and represent a major problem to both conservation strategies, and functionality of the ecosystems. In the last centuries, sika deer (Cervus nippon) have been widely spread from their native areal (China, Japan, Viet Nam, Korea, Taiwan and Russia) across most continents and they are nowadays considered one of the most invasive existing mammal species. In this study, we jointly used two software tools (VOSviewer and CiteSpace) to quantitatively review and investigate the global scientific literature on the sika deer. We reviewed and analysed the patterns and trends in global scientific literature on the species, performing co-authorship and co-occurrence analyses and creating relative network maps. The results showed a high and constant productivity of Japan, followed by China and USA, with China having an increase in production over the last years. Keywords as "hybridization" and "introgression" figured among the most frequently investigated topics, suggesting genetics as an important field of research, followed by the impacts of the species on the vegetation. Out of the species native range, the most productive country was the UK, followed by Germany and Czech Republic, with similar preferences for the topic of "hybridization" and "introgression". In addition, we investigated the presence of keywords that experienced an abrupt increase in number of citations (i.e. "citation burst") across the sika deer scientific literature. The analysis confirmed the previously described trends, highlighting the importance of genetic studies applied to the native fauna. We concluded that the scientific production trends on sika deer follow different and defined research flows according to the area of investigation. In addition, it is possible to notice that countries with the biggest or most invasive populations are also the most prolific. Lastly, this study highlighted the usefulness of integrating different methodologies and approaches to investigate topics in scientific literature through the support of informatics tools.