Potential (residual) loss and damage may result from the erosive effects of using plastics and coral stones as filling materials for raising floors, making the islands vulnerable in the long term. Historically, Batasan and, to some extent, Ubay have used coral stones to reclaim land where new families could build their new homes. Coral mining was thus done gradually, as the communities’ populations grew organically. However, after the earthquake, many households (especially from Batasan) concurrently mined corals from the reefs to elevate their floors (Jamero et al. 2017). Thus, while raising floors using coral stones may have short-term merits, its negative effects may prove far greater in the long term. In this sense, coral mining can be considered as a maladaptive strategy (Jamero et al. 2017).

Using coral stones to elevate floors has been a practice in the case study areas. Particuarly for Batasan, alternative building materials are not available hence people resort to using coral stones. It appears to be a knowledge passed down from one generation to another. They also do not receive technical assistance on alternative solutions so they continue with such practices.

Using coral stones to elevate floors has been a practice in the case study areas to reclaim land for housing purposes. After the earthquake in Bohol in 2013, coral mining became more rampant practice to raise floors. Residents have also started using plastic waste as foundations for their new houses or as filling materials for their elevated floors.

Excessive coral mining destroys the reefs, which serve as natural barriers against high waves, and reduces the sediment budget necessary for enabling the natural adaptation of islands to changing environmental conditions (Webb and Kench 2010). However, residents justified coral mining by arguing that they are only harvesting dead corals, not knowing that under the right conditions these can still potentially serve as settlements for coral recruits (Vermeij et al. 2009). Thus, while raising floors using coral stones may have short-term merits, its negative effects may prove far greater in the long term. In this sense, coral mining can be considered as a maladaptive strategy (Jamero et al. 2017). A survey of a mined reef section in Batasan revealed a live hard coral cover of less than 10%, with a further 30% of dead coral with algae, indicating that the area is already severely degraded (Jamero et al. 2017). When plastics are not properly trapped due to poor construction techniques, they can easily find their way into the marine environment especially during the passage of destructive typhoons. Plastics can harm marine animals primarily through entanglement and ingestion (Derraik 2002).

• Jamero, M.L., Onuki, M., Esteban, M. and Tan, N., 2018. Community-based adaptation in low-lying islands in the Philippines: challenges and lessons learned. Regional Environmental Change, 18(8), pp.2249-2260. https://doi.org/10.1007/s10113-018-1332-8 https://doi.org/10.1007/s10113-018-1332-8

• Atterms, M. S., T. Thaler, E. Genovese and S. Fuchs. 2019. Implementation of property-level flood risk adaptation (PLFRA) measures: Choices and decisions. WIREs Water https://doi.org/10.1002/wat2.1404