Table 2. Questions to guide monitoring and research priorities.
Questions arising from current knowledge gaps, and examples of ecological and socio-economic metrics to tailor monitoring to the questions for each stage of a rubble field repair intervention.
| Question | Ecological metrics | Socio-economic metrics |
|---|---|---|
| Before intervention | ||
| What are the reasons for the rubble field? | • Nature and history of acute disturbance (eg cyclones, crown-of-thorns starfish, coral bleaching) | • Human use of the area |
| • History of human impacts | ||
| • Metrics related to chronic stressors (e.g. turbidity, pollution, ongoing destructive fishing) | ||
| Is the rubble field problematic? | • Repeated measurements of percentage cover of rubble compared to live coral and hard carbonate over time | • Value of the area to fisheries and tourism industries? |
| • Importance of intactness and aesthetic appeal? | ||
| • Hydrodynamic properties of the site and rubble movement rates | ||
| • Count and size of coral recruits | ||
| • Fish loss | ||
| • Coral recruit growth and survival | ||
| • Succession of consolidation and its implication on natural recovery dynamics (Percentage cover of encrusting organisms on rubble; spot sampling of whether rubble pieces are bound or not) | ||
| What are the conditions preventing recovery? | • Wave and current data | • Human use of the area |
| • Insufficient coral recruitment | ||
| • Rubble movement that can be tolerated by coral recruits/juveniles | ||
| • Sediment loads | ||
| • Algal cover and herbivore biomass | ||
| • Larval supply | ||
| During intervention | ||
| What will work best? | • Determine ecological objectives and relevant metrics | • Cost and benefit analysis |
| • Socio-economic risk assessment | ||
| • Spatial scale | ||
| • Determine socio-economic objectives and relevant metrics | ||
| • Ecological risk assessment | ||
| During & after intervention | ||
| Is the method appropriate? | • Structural integrity of material over time | • Community/visitor concerns/ support/ benefits |
| • Changes in rubble movement / consolidation rates | ||
| • Traditional Owner/Indigenous concerns/ support/ benefits | ||
| • Monitoring of identified risks (e.g. hitchhiking organisms, microbial communities, introduction of foreign material, marine debris) | ||
| • Introduction and safe storage / isolation of foreign materials | ||
| Is the method working? | • Monitoring tailored to measure metrics relevant to intervention objectives | • Monitoring tailored to measure metrics relevant to intervention objectives |
| • Examples: percent cover of rubble vs. consolidated substratum, coral recruitment and recruit survival, coral cover, structural complexity, fish assemblage structure, abundance and biomass. | ||
| • Examples: aesthetic appeal, tourism and fisheries benefit, cultural significance, community participation | ||
| • Control sites for comparison–both undamaged and unrestored | ||
| • Coral donor source monitoring if corals transplanted or grown | ||