About this document
This is a prototype of an automatic report that documents how the user specified the operating model and their various justifications.
Introduction
- Describe the history and current status of the fishery, including fleets, sectors, vessel types and practices/gear by vessel type, landing ports, economics/markets, whether targeted/bycatch, other stocks caught in the fishery.
Coming soon!
- Describe the stock’s ecosystem functions, dependencies, and habitat types.
Coming soon!
- Provide all relevant reference materials, such as assessments, research, and other analysis.
The primary source for specifying this FRAME questionnaire is the 2016 Stock Synthesis assessment conducted by Dr Adam Langley. ://drive.google.com/open?id=1XbRRpJkMcISUY3yCcr_LRVyBShMjj8zwdates for the assessment run from 1950-2015, a total of 66 years.
Fishery Characteristics
Longevity
|
Answered
|
|
Very short-lived (5 < maximum age < 7)
|
|
Short-lived (7 < maximum age < 10)
|
|
Moderate life span (10 < maximum age < 20)
|
|
Moderately long-lived (20 < maximum age < 40)
|
|
Long-lived (40 < maximum age < 80)
|
|
Very long-lived (80 < maximum age < 160)
|
|
Justification
|
|
Mature natural mortality rate is high between 0.4 and 0.8. The current assessment vector for age 2-6+ is 0.552, 0.756, 0.756, 0.596, 0.551. E.g.://drive.google.com/open?id=1ova2OECyfb6DPlg5rPXOspRK7be7_29g
|
Stock depletion
|
Answered
|
|
Crashed (D < 0.05)
|
|
Very depleted (0.05 < D < 0.1)
|
|
Depleted (0.1 < D < 0.15)
|
|
Moderately depleted (0.15 < D < 0.3)
|
|
Healthy (0.3 < D < 0.5)
|
|
Underexploited (0.5 < D)
|
Resilence
|
Answered
|
|
Not resilient (steepness < 0.3)
|
|
Low resilience (0.3 < steepness < 0.5)
|
|
Moderate resilence (0.5 < steepness < 0.7)
|
|
Resilient (0.7 < steepness < 0.9)
|
|
Very Resilient (0.9 < steepness)
|
|
Justification
|
|
The assessment assumes a steepness value of 0.8 (Table 4, page 16)
|
Historical effort pattern
|
Answered
|
|
Stable
|
|
Two-phase
|
|
Boom-bust
|
|
Gradual increases
|
|
Stable, recent increases
|
|
Stable, recent declines
|
Inter-annual variability in historical effort
|
Answered
|
|
Not variable (less than 20% inter-annual change (IAC))
|
|
Variable (maximum IAC between 20% to 50%)
|
|
Highly variable (maximum IAC between 50% and 100%)
|
|
Justification
|
|
The annual fishing mortality rates of the assessment vary by around 10-15%.://drive.google.com/open?id=1XiW2LCO4EPr-UfaBfK3tbF6arIYznHuu
|
Historical fishing efficiency changes
|
Answered
|
|
Declining by 2-3% pa (halves every 25-35 years)
|
|
Declining by 1-2% pa (halves every 35-70 years)
|
|
Stable -1% to 1% pa (may halve/double every 70 years)
|
|
Increasing by 1-2% pa (doubles every 35-70 years)
|
|
Increasing by 2-3% pa (doubles every 25-35 years)
|
|
Justification
|
|
Hard to quantify but efficiency is likely to be improving since yellowfin are actively targeted. Would need to see the slope of log(F/E) to evaluate this.
|
Future fishing efficiency changes
|
Answered
|
|
Declining by 2-3% pa (halves every 25-35 years)
|
|
Declining by 1-2% pa (halves every 35-70 years)
|
|
Stable -1% to 1% pa (may halve/double every 70 years)
|
|
Increasing by 1-2% pa (doubles every 35-70 years)
|
|
Increasing by 2-3% pa (doubles every 25-35 years)
|
|
Justification
|
|
Future projections are assumed to be using current technology.
|
Length at maturity
|
Answered
|
|
Very small (0.4 < LM < 0.5)
|
|
Small (0.5 < LM < 0.6)
|
|
Moderate (0.6 < LM < 0.7)
|
|
Moderate to large (0.7 < LM < 0.8)
|
|
Large (0.8 < LM < 0.9)
|
|
Justification
|
|
Fish grow to between 121 and 180 cm and are thought to mature around 100cm.
|
Selectivity of small fish
|
Answered
|
|
Very small (0.1 < S < 0.2)
|
|
Small (0.2 < S < 0.4)
|
|
Half asymptotic length (0.4 < S < 0.6)
|
|
Large (0.6 < S < 0.8)
|
|
Very large (0.8 < S < 0.9)
|
|
Justification
|
|
Fish as small as 20cm are reported in the catch.
|
Selectivity of large fish
|
Answered
|
|
Asymptotic selectivity (SL = 1)
|
|
Declining selectivity with length (0.75 < SL < 1)
|
|
Dome-shaped selectivity (0.25 < SL < 0.75)
|
|
Strong dome-shaped selectivity (SL < 0.25)
|
|
Justification
|
|
The assessment estimates 90% selectivity of large individuals.
|
Discard rate
|
Answered
|
|
Low (DR < 1%)
|
|
Low - moderate (1% < DR < 10%)
|
|
Moderate (10% < DR < 30%)
|
|
Moderate - high (30% < DR < 50%)
|
|
High (50% < DR < 70%)
|
|
Justification
|
|
Discarding is assumed to be negligible.
|
Post-release mortality rate
|
Answered
|
|
Low (PRM < 5%)
|
|
Low - moderate (5% < PRM < 25%)
|
|
Moderate (25% < PRM < 50%)
|
|
Moderate - high (50% < PRM < 75%)
|
|
High (75% < PRM < 95%)
|
|
Almost all die (95% < PRM < 100%)
|
|
Justification
|
|
Not meaningful since discard rate is negligible. Post release mortality likely to be moderate to high given predominance of longline and purse seine gears.
|
Recruitment variability
|
Answered
|
|
Very low (less than 20% inter-annual changes (IAC))
|
|
Low (max IAC of between 20% and 60%)
|
|
Moderate (max IAC of between 60% and 120%)
|
|
High (max IAC of between 120% and 180%)
|
|
Very high (max IAC greater than 180%)
|
|
Justification
|
|
The stock assessment assumes a log prior standard deviation of 0.6 (the bin definition separating Moderate and High recruitment variability here). .
|
Size of an existing MPA
|
Answered
|
|
None
|
|
Small (A < 5%)
|
|
Small-moderate (5% < A < 10%)
|
|
Moderate (10% < A < 20%)
|
|
Large (20% < A < 30%)
|
|
Very large (30% < A < 40%)
|
|
Huge (40% < A < 50%)
|
|
Justification
|
|
No spatial closures.
|
Spatial mixing (movement) in/out of existing MPA
|
Answered
|
|
Very low (P < 1%)
|
|
Low (1% < P < 5%)
|
|
Moderate (5% < P < 10%)
|
|
High (10% < P < 20%)
|
|
Fully mixed
|
|
Justification
|
|
Ignorable given the previous answer of zero spatial closures. In any case, high mixing of these migratory fish.
|
Size of a future potential MPA
|
Answered
|
|
None
|
|
Small (A < 5%)
|
|
Small-moderate (5% < A < 10%)
|
|
Moderate (10% < A < 20%)
|
|
Large (20% < A < 30%)
|
|
Very large (30% < A < 40%)
|
|
Huge (40% < A < 50%)
|
|
Justification
|
|
Here we investigate a possible future closure of 10-20%.
|
Spatial mixing (movement) in/out of future potential MPA
|
Answered
|
|
Very low (P < 1%)
|
|
Low (1% < P < 5%)
|
|
Moderate (5% < P < 10%)
|
|
High (10% < P < 20%)
|
|
Fully mixed
|
|
Justification
|
|
High to very high mixing is assumed among the closure and the open areas.
|
Initial stock depletion
|
Answered
|
|
Very low (0.1 < D1 < 0.15)
|
|
Low (0.15 < D1 < 0.3)
|
|
Moderate (0.3 < D < 0.5)
|
|
High (0.5 < D1)
|
|
Asymptotic unfished levels (D1 = 1)
|
|
Justification
|
|
The assessment assumed unfished initial conditions.
|
Management Characteristics
Types of fishery management that are possible
|
Answered
|
|
TAC (Total Allowable Catch): a catch limit
|
|
TAE (Total Allowable Effort): an effort limit
|
|
Size limit
|
|
Time-area closures (a marine reserve)
|
|
Justification
|
1. Describe what, if any, current management measures are used to constrain catch/effort.
2. Describe historical management measures, if any.
3. Describe main strengths and weaknesses of current monitoring and enforcement capacity.
4. Describe and reference any legal/policy requirements for management, monitoring and enforcement.
|
TAC offset: consistent overages/underages
|
Answered
|
|
Large underages (40% - 70% of recommended)
|
|
Underages (70% - 90% of recommended)
|
|
Slight underages (90% - 100% of recommended)
|
|
Taken exactly (95% - 105% of recommended)
|
|
Slight overages (100% - 110% of recommended)
|
|
Overages (110% - 150% of recommended)
|
|
Large overages (150% - 200% of recommended)
|
|
Justification
|
|
Very large overages are possible.
|
TAC implementation variability
|
Answered
|
|
Constant (V < 1%)
|
|
Not variable (1% < V < 5%)
|
|
Low variability (5% < V < 10%)
|
|
Variable (10% < V < 20%)
|
|
Highly variable (20% < V < 40%)
|
|
Justification
|
|
These overages may be highly inconsistent.
|