Finding. The white-bellied heron, under 60 birds, has a genome now. It is sister to the purple heron. Mitochondrial and nuclear trees agree there and drift apart deeper in the heron family. Compared with the great blue heron, this species is almost out of heterozygosity and striped with homozygosity. The tract lengths and PSMC say that smallness is old. The two sampled birds do not share the same recent inbreeding load. The danger is not only last year’s crash. It is a lineage that has been rare for a long time and may have little left to adapt with.
Why this paper matters
Conservation genomics has to decide whether rarity is new or chronic. Chronic changes the strategy. Mitochondria add a phylogenetic subplot, not a disease.
What they actually measured
Reference genome, mito/nuclear trees, diversity, ROH, PSMC.
How to read the score
Around 60. Score 60.
What to do with it
If you manage A. insignis, treat Ne as long-small and genotype more birds for long ROH. If you study ardeid phylogeny, note the mitonuclear split. The directional implication is that this heron survived prolonged demographic adversity, and remaining genetic options may be thinner than a recent-bottleneck story implies.