Inconspicuous Hermit? Conservation Management Implications from a Decade of Online Wildlife Trade Trends for Land Hermit Crabs

Wildlife trade poses a significant challenge to biodiversity conservation, yet invertebrate species often receive less attention. In this study, we focused on land hermit crabs to analyze 10 years of data from Japan's largest online selling platform, alongside public interest trends. Our findings reveal that a total of five species and 6,862 individuals were sold over the past decade. Notably, the number of individuals sold annually and the total revenue significantly increased, correlating with Google Trends data, which suggests rising popularity and demand. The price of these crabs may reflect consumer preferences and potential impacts on species conservation. Our analysis shows that body size, species, and the number of individuals per sale influence price. Additionally, while price is also affected by coloration in certain species and body sizes, no clear pattern was observed. A significant trend we identified is the increase in the proportion of small-sized crabs sold, alongside a decrease in large and extra-large sizes, which could indicate over-fishing. The selling season peaked during the summer, with a small number of sellers accounting for a large share of sales, most of whom were based in Okinawa. This study offers valuable insights for policymakers, including the need to manage catch volumes and sizes, collaborate with local stakeholders, and re-evaluate selling certifications. Importantly, it provides the first evidence of long-term trade in land hermit crabs, offering critical information for the conservation of these popular exotic invertebrates globally.