Category: Ecology

Summary: Estimating when within-colony symbiont exchange turns a hot-sector bleaching collapse into a balanced rescue bridge linking stressed and refuge regions inside a coral colony.

Coral bleaching is not spatially uniform: heat stress, local refuges, and symbiont shuffling can vary within a single colony. This experiment asks when stronger exchange of symbionts within the colony allows the dominant mode to stop collapsing on a hot outer sector and instead connect hot sectors, sheltered refuges, and canal-like pathways into a rescue configuration.

The script builds dense non-symmetric within-colony exchange matrices and uses iterative deepening with repeated eigenanalysis to bisect the exchange threshold across system sizes from N=64 to 2048. It focuses on whether the leading mode becomes a bridge-like recovery pathway, rather than remaining dominated by one overheated rim region.

That framing is useful because recovery may depend on internal transport structure as much as on overall thermal stress. The docstring positions the work as a finite-size threshold map for within-colony rescue modes, distinct from broader bleaching and symbiont-shuffling studies.

Method: Dense non-symmetric eigenanalysis with iterative deepening and bisection on within-colony symbiont-exchange strength.

What is measured: Critical exchange threshold, hot-sector versus refuge-bridge dominance of the leading mode, recovery-pathway structure, and bracket width.