FA-65343 / Ecological population dynamics / Member archive

Discrete logistic population with constant quota harvest: crowding feedback · case 03

Stocks never settle at carrying capacity; growth follows the initial density forever.

Member previewVariant 3 · 3 implementations · 7 checks per implementation

Case contract

Each year the quota is removed first; if the stock is then <= 0 the trajectory records 0.0 and stops; otherwise the survivors grow by r*N*(1-N/K); the trajectory starts with the unharvested N0; values rounded to 4; None for K<=0 or negative N0.

Why this case matters

Population projections set harvest quotas, conservation status and pest-control timing; a wrong update order, boundary or rate conversion silently changes management advice.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: cod-like stock light quota	`[500.0, 576.0, 667.2, 776.64, 907.968, 1065.5616, 1254.6739, 1481.6087, 1753.9304]`	`[500.0, 579.84, 658.4077, 730.745, 792.9796, 843.1725, 881.3963, 909.1534, 928.5772]`	Failed

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