Step 7. Performance Indicators and Reference Points
Performance Indicators (PIs):
Three Performance Indicators have been identified to monitor and assess the status of each representative species of the four fish baskets for this hypothetical nearshore multispecies tropical reef fish fishery:
- MPA Density Ratio,
- Total Catch from the previous season, and
- Fishing Mortality (F).
These PIs were identified during a stakeholder working group that included representatives from the government, fishing community and the tourist industry. These stakeholders examined the data available (total catch, length frequency data from the catch and recent fishery independent monitoring) and selected measurable metrics that could help them track progress toward their fishery management goals. The three selected PIs were chosen because they are feasible to collect data on and to work with, because they provide information about the status the fishery on both individual and multispecies levels, and because they represent two different data streams which allows stakeholders to gain a more complete understanding of the fishery and to reduce uncertainty associated with any one data stream.
Reference Points (RPs):
Determining the appropriate Reference Points for any Performance Indicators will depend on previous trends in existing data, as well as best practices from the literature. These data should be analyzed, and the results discussed by a relevant group of stakeholders and scientists in order to determine the best target and limit RPs. Stakeholders in our case study decided to use a three year running average to determine the appropriate RPs for both the MPA Density Ratio and Total Catch PIs in order to incorporate natural stochasticity in fish populations. They drew their RPs for the Fishing Mortality rate (F) from the literature.
Performance Indicators with Target and Limit Reference Points:
Performance Indicators |
Target Reference Point |
Limit Reference Point |
Data Source |
Justification |
MPA density ratio |
> 0.6 target species |
< 0.4 target species |
Fishery Independent Underwater Survey |
Fish and invertebrates, that are habitat associated, not a good indicator for highly mobile targets. |
Total catch from the, previous season |
Increase in Total Landing |
Rapidly Decreasing Total, Landings, previous year or in comparison to running average |
Catch Trends |
All targets that do not, have high selectivity of habitat stratification. |
Fishing mortality |
F/M <1 (F is fishing, mortality, M is natural mortality) |
F=2M |
Length frequency of the, catch |
When sampling is, stratified across the fishery, can provide an estimate of abundance. |