Step 6: Performance Indicators
To manage a fishery, we need to know how it is doing with respect to fishery management goals; in other words, we need performance indicators (PIs) that can be measured. Ideally, several PIs will be identified that can be evaluated with independent data streams (for example, fishing mortality and Spawning Potential Ratio (SPR) calculated from length composition of the catch, plus MPA density ratio calculated from visual census data) so that they can be used to corroborate each other and reduce uncertainty about the status of the fishery.
Once a set of PIs have been selected that can tell us how we’re doing at meeting our goals, we’ll identify appropriate Reference Points (RPs) against which to compare them (Step 7), determine some Harvest Control Rules (HCRs) to dictate our choices once our PI measurements come in (Step 8), and then select and conduct the appropriate assessments to confidently measure those PIs given the data we have available (Step 9).
Selecting PIs in a Multi-Species Fishery
If you are using management baskets to help avoid serial depletion in a multispecies fishery, from this point in the FISHE process onward only the representative species from each basket will be examined. This means that extreme care must be taken when selecting Performance Indicators (PIs) (as well as corresponding Reference Points – Step 7), and when interpreting the results of the assessments (Step 9 and 10).
After PIs have been selected based on goals and data available, ask yourself if trends in the data for the representative species on each PI are likely to characterize/ represent trends for the other species in the basket. In other words, will the various factors (e.g. fishing rate, gear used, etc.) influence all species in the basket in the same way the influence the representative species? Or is there some characteristic of the other species that makes it different, such that a given PI result will not mean the same thing as it does for the representative species? It may be necessary to consult with scientists, the fishermen, or other system experts to find answers to these questions.
If you determine that PI values for the representative species may not reflect changes for all species in the basket, it may be necessary to pick a different, or a second, representative species, or to select an alternate PI to assess. Alternatively, the same representative species and PI can be used, but Reference Points can be set at levels that are appropriate for the most vulnerable species in the basket. See Step 7 for more information.
Here are some examples of performance indicators for specific goals:
|Sustainable yields||Fishing mortality rate (F), Spawning Potential Ratio (SPR), % of the catch that is mature|
|Strong fishery profits||Catch Per Unit Effort (CPUE)|
|Healthy stocks and ecosystems||MPA Density Ratio|
For step-by-step guidance on choosing the appropriate PIs for your fishery, see the Guidance document for choosing PIs, identifying RPs, and defining HCRs in the downloadable workbook, and linked on this page.