Coastal citizen science monitoring and suggested conservation strategy: ghost crab survey at Suao Dakenggu, Taiwan

Beaches provide a buffer zone between the sea and the land, which mitigates the impact of natural hazards on waterfront residents. In this study, the beach at the Dakenggu community in Suao Township, Yilan, was used as a long-term monitoring site for ghost crabs. The survey was conducted by researchers in collaboration with local residents, which can be considered community-based citizen science. In collaboration, researchers and residents conducted monthly surveys. The findings showed that Ocypode sinensis was a dominant species on the Dakenggu beach. Juvenile O. sinensis were more abundant in the spring (April) and the summer (July–September). Except in September, no sex predominance was observed in other months, which may be related to the breeding period of the crabs. As far as other data are concerned, O. sinensis females were significantly larger than males, and O. sinensis occurrences exhibited a significant positive correlation with temperature and a significant negative correlation with relative humidity when weather data for the survey days were analyzed. Multiple studies have shown that the ghost crab population is highly affected by offroad vehicle use on the beach. As a result, local residents can use the findings of this study to develop corresponding conservation strategies, such as permitting off-road vehicle use only in the winter (November–February) and planting coastal plants as natural barriers to prevent vehicles from destroying ghost crab habitat. Long-term environmental monitoring through community-based citizen science can document changes in the local environment, and such information can be the basis for increased community resilience to face the challenges posed by environmental change.