Fair Trade USA Data-Limited Stock Assessment Decision Tree

Transcription

1 Fair Trade USA Data-Limited Stock Assessment Decision Tree January 31, 2014 Introduction This stock assessment decision tree may be used to determine which data-limited stock assessment methodology is most appropriate for your fishery. It also outlines the appropriate follow-up actions and Fair Trade USA (FTUSA) certification requirements based on the status of the stock. This document should not be used for stocks with sufficient data to conduct a formal stock assessment. In such cases, a formal stock assessment should be conducted as outlined by FAO standards 1. Directions 1. Determine which species category you are assessing: a) Is the species classified as Endangered, Threatened, or Protected (ETP)? If so, use Decision Tree 1 on page 3 (see RM BD 1 of the FTUSA Capture Fisheries Standard). Boxes outlined in blue pertain to ETP species. b) Is the species classified as Major Main Retained 2, Main Retained 3, or Minor Retained 4? If so, use the appropriate Decision Tree on pages 4 and 5. All Retained species must be assessed annually (see RM OF 1 of the FTUSA Capture Fisheries Standard). Boxes outlined in green pertain to Table 1. Boxes outlined in orange pertain to the c) Is the species classified as Main Bycatch 5 or Minor Bycatch 6? If so, use the appropriate Decision Tree on pages 6 or 7. All Bycatch species must be assessed annually (see RM OF 2 of the FTUSA Capture Fisheries Standard). Boxes outlined in orange pertain to the FTUSA Productivity & Susceptibility Analysis 2. For Major Main Retained and Main Retained species, if sufficient data exist, conduct data-limited stock assessments to analyze at least three performance indicators (see Table 1). a) If three of three performance indicators show a positive trajectory: Continue to maintain responsible fishing practices to ensure the stock status remains stable. Continue to gather data as outlined in the FTUSA Capture Fisheries Standard. b) If two of three performance indicators show a positive trajectory: The Market Access Provider (MAP)/Fisher Association (FA) must include in the Fishery Management Plan a strategy to reduce fishing pressure and improve the performance indicators within six years. Continue to gather data as outlined in the FTUSA Capture Fisheries Standard. c) If only one of three performance indicators shows a positive trajectory: The fishery cannot be certified. 1 FAO (2003). Fish Stock Assessment Manual. FAO Fisheries Technical Paper, Retrieved from 2 Major Main Retained Species: >25% of any one species landed, in two consecutive years. Species in this category may NOT be classified as ETP species. 3 Main Retained Species: >10% of any one species landed. Species in this category may NOT be classified as ETP species. 4 Minor Retained Species: <10% of any one species landed. Species in this category may be classified as ETP species. 5 Main Bycatch Species: >10% of any one species discarded. Species in this category may NOT be classified as ETP species. 6 Minor Bycatch Species: <10% of any one species discarded. Species in this category may be classified as ETP species. 1

2 3. For Minor Retained species, if sufficient data exist, conduct data-limited stock assessments to analyze at least three performance indicators (see Table 1). a) If three of three performance indicators show a positive trajectory: Continue to maintain responsible fishing practices to ensure the stock status remains stable. Continue to gather data as outlined in the FTUSA Capture Fisheries Standard. b) If two of three performance indicators show a positive trajectory: The Market Access Provider (MAP)/Fisher Association (FA) must include in the Fishery Management Plan a strategy to reduce fishing pressure and improve the performance indicators within six years. Continue to gather data as outlined in the FTUSA Capture Fisheries Standard. c) If only one of three performance indicators shows a positive trajectory: The Market Access Provider (MAP)/Fisher Association (FA) must include in the Fishery Management Plan a strategy to reduce fishing pressure and improve the performance indicators within six years. Continue to gather data as outlined in the FTUSA Capture Fisheries Standard. 4. If sufficient data for Major Main Retained, Main Retained, or Minor Retained species do not exist, conduct a using the FTUSA Productivity & Susceptibility Analysis Worksheet to determine total vulnerability to overfishing. Follow-up actions are outlined in the Decision Trees on pages 4 and 5. References Babcock, E. A. and MacCall, A. D. (2011). How useful is the ratio of fish density outside versus inside no-take marine reserves as a metric for fishery management control rules? Canadian Journal of Fisheries and Aquatic Sciences, 68, Froese, R. (2004). Keep it simple: three indicators to deal with overfishing. Fish and Fisheries, 5,

3 Table 1: Stock Assessment Performance Indicator Trajectories Stock Assessment Performance Indicator Positive Trajectory Negative Trajectory Density Ratio Fished Area/Unfished Area (Babcock and MacCall, 2011) Fishing Mortality All fish > 0.8 Mature fish > 0.6 Fishing mortality < Natural mortality All fish < 0.8 Mature fish < 0.6 Fishing mortality > Natural mortality Spawning Potential Ratio (SPR) SPR > 40% SPR < 40% Percentage of Mature Fish in Catch (Froese, 2004) Percentage of Fish Caught at Optimal Length (Froese, 2004) Percentage of Megaspawners in Catch (Froese, 2004) > 90% < 90% > 90% < 90% < 10% > 10% Change in Average Length Abundance (Catch/Effort) Change in Catch-Per-Unit-Effort (CPUE) Avg. length is staying the same or increasing Abundance is staying the same or increasing CPUE is increasing over time Questions to consider when analyzing the performance indicators: 1. Are the length-based indicators consistent with each other? 2. Are the length-based indicators consistent with a non length-based indicator? See References for primary literature. Avg. length is decreasing Abundance is decreasing CPUE is decreasing over time Decision Tree 1: Endangered, Threatened, or Protected (ETP) Species Endangered, Threatened, or Protected (ETP) Species All ETP species listed under RM IN 1.2, regardless of percentage caught or landed. Are ETP species caught or landed in the fishery? Do they fall under any of the following categories: Major Main Retained Species, Main Retained Species, or Main Bycatch Species? The fishery cannot be certified. The fishery must reduce retention and/or discards of individual ETP species to <10% to be eligible for certification. MAP and FA must include in the Fishery Management Plan a strategy to ensure all ETP laws are adhered to and retention and/or bycatch of ETP species does not increase. 3

4 Decision Tree 2: Major Main Retained and Main Retained Species Major Main Retained Species and Main Retained Species May not be classified as ETP species. census data for this Do you have length data from the catch Do you have catchper-unit effort (CPUE) data census data inside and outside enforced notake areas? Do you have catch records for this Use Table 1 to determine if the CPUE performance indicator is showing a positive or negative trajectory. Calculate a fish density ratio, by dividing the density in the fished area/density in the unfished area. Use Table 1 to determine if the performance indicator is Create a catch curve to calculate fishing mortality (F), Spawning Potential Ratio (SPR), the three Froese Sustainability Indicator, and/or change in average length over time. Use Table 1 to determine if the performance indicators are showing a positive or Calculate annual abundance by dividing catch/effort. Use Table 1 to determine if the performance indicator is < >2 Continue to maintain responsible fishing practices to ensure vulnerability does not increase. Continue to gather fishery data. The MAP and FA must include in the Fishery Management Plan a strategy to reduce the total to <1.8 within six years. If vulnerability cannot be reduced to <1.8 due to biological characteristics of the species, vulnerability must decrease to its lowest possible score. The fishery cannot be certified. The fishery must reduce fishing pressure to decrease total vulnerability to <2 to be eligible for certification. 4

5 Decision Tree 3: Minor Retained Species Minor Retained Species May be classified as ETP species. census data for this Do you have length data from the catch Do you have catchper-unit effort (CPUE) data census data inside and outside enforced notake areas? Do you have catch records for this Use Table 1 to determine if the CPUE performance indicator is showing a positive or negative trajectory. Calculate a fish density ratio, by dividing the density in the fished area/density in the unfished area. Use Table 1 to determine if the performance indicator is Create a catch curve to calculate fishing mortality (F), Spawning Potential Ratio (SPR), the three Froese Sustainability Indicator, and/or change in average length over time. Use Table 1 to determine if the performance indicators are showing a positive or Calculate annual abundance by dividing catch/effort. Use Table 1 to determine if the performance indicator is < >2 Continue to maintain responsible fishing practices to ensure vulnerability does not increase. Continue to gather fishery data. The MAP and FA must include in the Fishery Management Plan a strategy to reduce the total to <1.8 within six years. If vulnerability cannot be reduced to <1.8 due to biological characteristics of the species, vulnerability must decrease to its lowest possible score. The MAP and FA must include in the Fishery Management Plan a strategy to reduce the total to <1.8 within six years. If vulnerability cannot be reduced to <1.8 due to biological characteristics of the species, vulnerability must decrease to its lowest possible score. 5

6 Decision Tree 4: Main Bycatch Species Main Bycatch Species May not be classified as ETP species. <1.8 Continue to maintain responsible fishing practices to ensure vulnerability does not increase The MAP and FA must include in the Fishery Management Plan a strategy to reduce bycatch of this species to <10% within six years. >2 The fishery cannot be certified. The fishery must reduce bycatch of this species to <10% to be eligible for certification. 6

7 Decision Tree 5: Minor Bycatch Species Minor Bycatch Species May be classified as ETP species. <1.8 Continue to maintain responsible fishing practices to ensure vulnerability does not increase The MAP and FA must include in the Fishery Management Plan a strategy to ensure fishing pressure on this species does not increase. >2 The MAP and FA must include in the Fishery Management Plan a strategy to ensure fishing pressure on this species does not increase. 7