Coupled Dynamics of Adaptive Capacity and Structural Rigidity as Indicators of Fisheries Collapse: A Low-Dimensional Dynamical Systems Analysis

2026/03/19 by Bernd von Mallinckrodt · 1 voice
Environmental Science · Physics and Astronomy · #Chaos control and synchronization #Ecosystem dynamics and resilience #Marine and fisheries research

paper · doi:10.5281/zenodo.19108468

openalex publication_date 2026/03/19 · openalex created_date 2026/03/20 · openalex updated_date 2026/07/01

Abstract

This preprint presents a low-dimensional dynamical systems analysis of pre-collapse dynamics in the North Atlantic Cod (Gadus morhua) stock, utilizing data from the RAM Legacy Stock Assessment Database (v4.64) and ICES stock advice (1970–1992). The study operationalizes two composite proxy indices — adaptive capacity R(t) and structural rigidity Φ(t) — derived from standard stock assessment quantities (B/B_MSY, F/F_MSY, recruitment deviation, TAC variability) and examines their coupled temporal dynamics in the decade preceding the 1992 stock collapse.Key findings include a strong negative correlation between R(t) and Φ(t) (r = −0.78, p < 0.01), a sustained pre-collapse decline in adaptive capacity beginning 8–12 years prior to collapse, and early warning statistics — AR(1) autocorrelation increasing from 0.35 to 0.82 and rolling variance increasing by approximately 40% — consistent with critical slowing down as predicted by bifurcation theory.The framework is positioned as a minimal, hypothesis-generating instrument complementary to established resilience theory (Holling, 1973; Scheffer et al., 2009; Dakos et al., 2008) and is not proposed as a causal model. Limitations regarding proxy validity, confounding environmental drivers, causal identification, and single-stock generalizability are explicitly addressed. The manuscript is structured for submission to journals in ecological complexity, nonlinear dynamics, or applied fisheries science. fisheries collapse · adaptive capacity · structural rigidity · resilience theory · critical transitions · early warning signals · critical slowing down · dynamical systems · North Atlantic Cod · Gadus morhua · RAM Legacy Database · bifurcation · AR(1) autocorrelation · regime shift · exploitation-exploration tradeoff · panarchy · stock assessment · B/B_MSY · F/F_MSY · socio-ecological systems

Discussions

• What if fisheries don’t collapse from randomness … but from rising structural rigidity and declining adaptive capacity? This preprint shows empirical evidence (North Atlantic cod) consistent with ea [bsky, 2 points, 0 comments]

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