# c16 — Coastal fishery intervention design (control-policy run)

## STATE

### problem
- **statement**: A coastal demersal single-stock fishery, open-access in practice, has 3 yrs declining CPUE and shrinking fish size. Assessment: harvest ~20% over MSY; recruitment-collapse threshold crossed in 4–7 yrs on current trajectory. ~120 small-boat operators across 5 villages depend on income; downstream processing buyers. Regulator has TAC authority but has historically deferred to industry.
- **constraints**: open-access (no enforced quotas); heterogeneous small operators; captured/deferential regulator; downstream economic chain; biological window 4–7 yrs.
- **success_criteria**: biomass returns to MSY-supporting range within 10 yrs AND <20% drop in aggregate fisher income (cohort average, not per-boat).
- **failure_criteria**: stock collapse OR a regime that pushes the bottom-quartile operators below subsistence.

### operative_primes
- `tragedy_of_the_commons` — type **mixed-framed**, salience **load_bearing**. Rivalrous + non-excludable stock; each boat captures full private catch benefit but bears ~1/N of the depletion cost → Nash over-extraction. This is the core diagnosis. (distinctive band, appears across 4 of 7 facets.)
- `irreversibility` — type **structural**, salience **load_bearing**. The recruitment-collapse threshold is a one-way basin escape; reversal cost ≫ forward cost. Supplies the precautionary weighting and the 4–7 yr window as a scarce resource.
- `mechanism_design_and_incentive_structure` / `free_riding` — type **framed/mixed**, salience **context→load_bearing**. The remedy must change the local decision environment, not exhort restraint. Folded into the governance design.
- `equity` / `procedural_fairness` (via `equity_adjustment`) — type **framed**, salience **load_bearing**. The bottom-quartile-subsistence failure criterion is a distributional floor that the raw commons solution does not by itself guarantee.
- `legitimacy` / `governance` — type **framed**, salience **load_bearing**. Captured regulator → rules must draw authority from the user community + transparent evidence, not from the deferential agency alone.
- (context-only, pruned: `scarcity`, `competition`, `coevolution`, `social_identity_theory` — describe the situation but removing them would not change the recommendation.)

### candidates
- `commons_governance` (source_prime = tragedy_of_the_commons; retrieval 0.715; **primary operative pattern**).
- `tipping_point_prevention` (source = tipping_points/nonlinearity/resilience, related = irreversibility; facet-fusion top archetype for the phasing facet; **secondary structure** — the threshold/precaution layer).
- `equity_adjustment` (source = equity/procedural_fairness; facet hit for the distributional facet; **secondary structure** — the income-floor layer).
- (declined: `public_goods_provision` — this is over-extraction not under-provision; `resource_rationing` — lacks legitimacy/stewardship/adaptation.)

---

## VERBS RUN (verb + why)

1. **match (retrieve)** — `search_by_facets` (7 facets) + `search_prime` (blended meta-model). Why: oblique multi-structure problem; a blended query would land in the cooperation/competition neighborhood and bury the governance + distributional facets. Result: `tragedy_of_the_commons` distinctive across facets; governance/equity/irreversibility surfaced per-facet. Post satisfied: ≥1 candidate with source-prime overlap.
2. **match (retrieve)** — `search_archetype` (meta-model). Why: find the operative *solution* pattern. Result: `commons_governance` (source prime = tragedy_of_the_commons) is the spine.
3. **salience-rank + prune** — kept 6 load-bearing primes; cut 4 context primes with ablation rationale (removing `scarcity` etc. does not change the design; removing `irreversibility` would drop the precautionary phasing → changes design → load_bearing).
4. **get_prime / get_archetype** — pulled `tragedy_of_the_commons`, `irreversibility`, `commons_governance`, `tipping_point_prevention`, `equity_adjustment` full records (components, anti-signatures, failure modes).
5. **compose** — built the relational model (below); checked referential integrity.
6. **lift (L1, situation→skeleton)** — domain-stripped meta-model (below); witness-checked.
7. **lift (L2, coverage-enforcement)** — coverage map over `commons_governance`'s 13 components (below), with `tipping_point_prevention` and `equity_adjustment` components folded in as homologs/instantiations where the primary pattern was thin (threshold-trigger logic; distributional floor).
8. **evaluate-fit (gate)** — walked all 4 commons_governance anti-signatures + 5 tipping_point_prevention anti-signatures against this scenario (below).
9. **reconcile** — applied commons_governance logic to the concrete model and the skeleton separately; the views diverge on *how fast to cut* — concrete model says "phase to protect income," skeleton (pure commons) says "cap at MSY now." Resolved toward the reading consistent with both: a feedback-triggered glide-path that respects the income floor while staying inside the biological window. (Views did disagree → meta-model not decorative.)

### compose — typed relational model (referential integrity check)
Nodes: `STOCK`(resource), `BOATS`(120 users, heterogeneous), `VILLAGES`(5 groups), `BUYERS`(downstream), `REGULATOR`(authority, captured), `TAC`(use-limit instrument), `MONITOR`(catch+biomass sensing), `COUNCIL`(co-governance body), `FLOOR`(subsistence guarantee).
Edges (every edge connects declared nodes; every load-bearing prime annotated):
- BOATS —extract→ STOCK [prime: tragedy_of_the_commons]
- STOCK —approaches→ COLLAPSE_THRESHOLD [prime: irreversibility]
- COUNCIL —sets/adapts→ TAC [prime: commons_governance/legitimacy]
- TAC —binds→ BOATS [prime: mechanism_design]
- MONITOR —reports condition→ COUNCIL [prime: feedback]
- COUNCIL —enforces graduated sanctions→ BOATS [prime: governance]
- FLOOR —protects→ bottom-quartile BOATS [prime: equity]
- REGULATOR —recognizes/backstops→ COUNCIL [prime: legitimacy]
- BUYERS —fund/stabilize→ FLOOR [prime: reciprocity]
Referential integrity: PASS (no dangling edges; all 6 load-bearing primes appear as annotations).

### lift L1 — domain-stripped skeleton (no domain terms)
- **Roles**: many independent drawers of a shared renewable pool; a pool with a renewal rate and a one-way failure threshold; a nominal authority that has ceded power to the drawers; a weakest sub-population with a survival floor; downstream dependents.
- **Relations**: private-benefit / shared-cost extraction; cumulative draw vs renewal; legitimacy flowing from the drawer-community; condition-signal → limit-revision.
- **Invariants**: pool stays above the failure basin; limit tracks observed condition; the floor sub-population is never pushed below survival; authority for the limit is accepted enough to be enforced.
- Witness check: every role/relation/invariant has a witness in the concrete model (STOCK, BOATS, REGULATOR, FLOOR, BUYERS, TAC, MONITOR, COUNCIL). No domain words remain in the skeleton. PASS.

---

## COVERAGE MAP — operative pattern: `commons_governance` (13 components)
(Threshold-layer = `tipping_point_prevention`; floor-layer = `equity_adjustment` folded in as homologs/instantiations.)

| # | Component | Status | Witness / Reason |
|---|-----------|--------|------------------|
| 1 | **Shared Resource Boundary** | instantiated | Define the managed unit as this single demersal stock within the fishery's grounds + the 120 registered operators across 5 villages as the rights-holding pool; outsiders (transient vessels) excluded by registration. |
| 2 | **Access Rule** | instantiated | Close de-facto open access: only the 120 currently-active operators (grandfathered) hold harvest rights; a registry caps entry. No new entrants during recovery. |
| 3 | **Use Quota or Use Limit** | instantiated | Cohort-wide total allowable catch set to a recovery glide-path: start ~10% below current harvest (not an immediate 20% cut), tightening on a biomass-triggered schedule toward MSY. Each operator gets a baseline share floor + a proportional share above it (so small boats are not squeezed out by a flat % cut). |
| 4 | **Monitoring Signal** | instantiated | Landing logs at the processing buyers (mandatory catch reporting at point of sale — cheap, hard to evade) + an annual fishery-independent biomass/size survey. Both feed the council dashboard. |
| 5 | **Sanction Rule** | instantiated | Graduated: warning → temporary share reduction → seasonal suspension for repeated/large violations. Proportional to harm, repetition, repairability. |
| 6 | **Replenishment Rule** | homolog | No active restocking; the homolog is *natural rebuilding under reduced pressure* — the glide-path itself is the replenishment mechanism, plus optional rotating no-take micro-reserves on spawning grounds to accelerate recruitment. Function (restore the stock) is served by a different mechanism than hatchery/funding. |
| 7 | **Legitimacy Basis** | instantiated | A co-management council with elected village seats sets and revises rules under transparent survey evidence; the regulator formally recognizes and backstops it. This converts the captured-regulator liability into community-sourced legitimacy + state recognition (Ostrom design principle 7). |
| 8 | **Dispute Resolution Path** | instantiated | Council-level appeals process for share disputes, hardship claims, and sanction challenges; documented decisions. |
| 9 | **Adaptation Cadence** | instantiated | Annual review tied to the biomass survey: the TAC glide-path tightens or loosens on observed condition, not a fixed number. Sunset/reassessment trigger built in. |
| 10 | **Contribution Rule** | instantiated | Operators owe accurate landings reporting + participation in survey days + a small per-landing levy funding monitoring and the stabilization fund (replenishment duty paired with access benefit). |
| 11 | **Funding Pool** | instantiated | Per-landing levy + buyer co-contribution funds (a) monitoring/survey costs and (b) the income-stabilization transfer to the bottom quartile during the steepest cut years. |
| 12 | **Exception Process** | instantiated | Hardship exception for bottom-quartile operators: a guaranteed minimum-share + stabilization top-up so a cohort-average income test does not silently sacrifice the weakest (this is the `equity_adjustment` Hardship/Resource-Targeting component lifted in — the distributional FLOOR). |
| 13 | **Transparency Record** | instantiated | Public council ledger of catches, biomass trend, sanctions, and fund disbursements — defends against capture and against surveillance overreach (proportional data only). |

**Threshold-layer cross-check (`tipping_point_prevention`):** Undesirable-Transition Definition = recruitment collapse [instantiated, comp.1+core idea]; Early-Warning Signal + Threshold Estimate = CPUE/size + biomass survey vs collapse threshold [instantiated, comp.4]; Intervention Window = the 4–7 yr biological window, treated as scarce → act before proof is conclusive [instantiated, glide-path starts immediately]; Stressor Reduction = the TAC cut [instantiated, comp.3]; Feedback Damping / Resilience Buffer = no-take spawning reserves [homolog, comp.6]; Precautionary Action Band = condition-triggered tightening [instantiated, comp.9]; Prevention Authority = council + regulator backstop [instantiated, comp.7]; Reversibility Check = correctly_declined as a *separate* component (the whole design IS the reversibility-preserving move; forcing it as a distinct artifact would duplicate comp.9).

**Floor-layer cross-check (`equity_adjustment`):** Relevant Difference + Barrier Map = bottom-quartile boats are capital/range-constrained, a flat % cut pushes them below subsistence [instantiated, comp.3+12]; Support/Rule Adjustment = baseline-share floor + stabilization transfer [instantiated, comp.11+12]; Core Standard = the biological cap is preserved, only the *distribution* of the cut is adjusted [instantiated]; Fairness Outcome Monitor = cohort + bottom-quartile income tracked, not just average [instantiated, comp.13]; Privacy/Dignity Safeguard = stabilization is rule-based, not advocacy-mediated [instantiated, comp.12].

**No component is `missing`. All 13 commons_governance components are instantiated (11) or homolog (1, Replenishment) — none declined; the one declined item (tipping's standalone Reversibility Check) belongs to the secondary pattern and is justified as a non-distorting decline.**

---

## evaluate-fit (anti-signature gate)

**commons_governance anti-signatures:**
1. "Resource fully private, use doesn't affect others" — NOT tripped (rivalrous + non-excludable stock). keep.
2. "Problem is under-provision of a non-rival benefit" — NOT tripped (this is over-extraction of a rival stock). keep.
3. "Central authority can directly allocate without legitimacy/info/enforcement problems" — NOT tripped — the regulator is *captured* and lacks enforcement legitimacy; that is precisely why co-management is needed. keep.
4. "Actually a one-time two-party dispute" — NOT tripped (120 actors, repeated game). keep.

**tipping_point_prevention anti-signatures:**
1. "Transition is desirable, cross deliberately" — NOT tripped (collapse is catastrophic). 2. "Gradual, reversible, ordinary monitoring suffices" — NOT tripped (recruitment collapse is hard-to-reverse). 3. "No credible threshold" — NOT tripped (assessment gives 4–7 yr threshold). 4. "No feasible pre-threshold action" — NOT tripped (TAC + reserves available). 5. "Only an alarm/dashboard, no intervention" — NOT tripped (design carries concrete extraction-reduction levers). keep.

**Verdict:** No anti-signature disqualifies the design. Both patterns fit. The one residual risk (capture of the *council* by powerful operators) is mitigated by transparency ledger + bottom-quartile guaranteed seats + regulator backstop — i.e. the design's own legitimacy/equity components answer the chief failure mode.

---

===RECOMMENDATION_BEGIN===
Treat the stock as a shared asset that is being drawn down faster than it rebuilds, and recognise the central trap: each boat keeps the full value of every extra fish but feels only a fraction of the collective loss, so individually sensible decisions are steering the whole cohort toward a collapse that nobody wants. Moral appeals to "fish less" will fail for exactly this reason — the restraint costs the restrainer everything and saves them almost nothing. The intervention must change the decision environment, protect the weakest operators by design, and act inside the four-to-seven-year window before the collapse threshold makes recovery impossible.

Stand up a co-management council with elected seats from each of the five villages, formally recognised and backstopped by the regulator. Because the agency has historically deferred to industry, its credibility is weak; legitimacy must instead come from the operators themselves plus transparent evidence, with the regulator's role being to recognise the council's rules and enforce against outsiders. Reserve guaranteed seats for smaller-boat operators so the council cannot be captured by the largest players.

Close the de-facto open access. Register the roughly 120 currently active operators as the rights-holding group, freeze new entry during recovery, and exclude transient vessels. This bounds who the resource is being protected for.

Set a cohort-wide total allowable catch on a glide-path rather than a one-time shock. Cutting the full twenty percent immediately would breach the income floor and trigger evasion; instead start around ten percent below current harvest and tighten on a schedule keyed to the annual stock survey, aiming to return biomass to its productive range within the decade. Crucially, allocate the catch so each operator receives a protected baseline share plus a proportional share above it — a flat percentage cut would push the bottom quartile under subsistence, which is itself a defined failure. The baseline floor, a hardship top-up, and a stabilization transfer funded during the steepest cut years keep the weakest boats viable while the stock rebuilds.

Make use and condition visible cheaply. Require catch to be reported at the point of sale through the processing buyers — this is hard to evade and turns the downstream chain into the monitoring backbone — and run a yearly fishery-independent biomass-and-size survey. Both feed a public council dashboard so that limits track the resource's actual condition rather than arbitrary numbers, which is what makes the limits defensible and obeyed.

Attach graduated, proportional consequences: a warning, then a temporary share reduction, then a seasonal suspension for repeated or large violations. Proportionality matters more than severity in a community that must keep cooperating year after year; disproportionate punishment would corrode the legitimacy the whole arrangement depends on.

Accelerate the biological rebound by closing rotating no-take micro-reserves over known spawning grounds. With reduced overall pressure, this is the main lever that lets the stock replenish itself within the window, substituting for any costly restocking.

Fund the system from within: a small per-landing levy plus a buyer co-contribution pays for monitoring, the survey, and the stabilization transfers. Operators owe accurate reporting and participation in survey days in return for their secured access — obligations are reciprocal and understandable, which is what sustains contribution. Maintain an appeals path for share and sanction disputes and a documented hardship process so adjustments are rule-based, not dependent on who advocates loudest.

Build in adaptation. Each year, the survey result either tightens or relaxes the glide-path; if biomass recovers faster than expected, catch can rise, and if it stalls, the cap tightens further. Keep a transparent public ledger of catches, biomass trend, sanctions, and fund disbursements to guard against both capture by powerful operators and overreach in monitoring.

Final operating rule: hold the cohort catch to the highest level the annual survey shows is consistent with biomass climbing back toward its productive range within ten years; distribute every cut through protected baseline shares and a stabilization fund so the bottom quartile never falls below subsistence; and let observed stock condition — not industry pressure or a fixed number — move the limit up or down each year.
===RECOMMENDATION_END===

COST: ~9 operations (1 ToolSearch, 1 corpus_stats, 1 search_by_facets ×2, 1 search_prime, 1 search_archetype, 4 get_prime/get_archetype, 1 Read, 1 Write), ~36k tokens.
