The Galapagos lava heron, a unique small heron found on the lava-strewn shores of Ecuador’s Galapagos Islands, has recently gained recognition for its distinct status.

Galapagos lava heron (Butorides sundevalli). Image credit: Casey Klebba / CC BY-SA 4.0.

Endemic to the Galapagos Islands, this slate-gray to black heron has intrigued ornithologists for years.

While some classify it under the widely distributed Great Heron (Butorides striatum) as a subspecies Butorides striata sundevari, others advocate for its recognition as a separate species, Butorides sundevalli.

Recent DNA analyses led by researchers from San Francisco State University and the California Academy of Sciences lend weight to the latter perspective.

“This bird, noted for its significant plumage variation, has long posed the question of whether it stands as a separate species or simply as a subspecies of mainland birds,” said Dr. Jamie Chavez, lead author of the study.

Through the examination of thousands of genetic markers and numerous museum specimens, researchers found that the Galapagos lava heron forms its own distinct evolutionary lineage, diverging from its supposed relatives.

Surprisingly, the lava heron shows closer genetic ties to the Gray Heron (Butorides virescens) from North and Central America than to the Great Heron.

The ancestors of the Galapagos lava heron may have arrived on the islands via unusual migration routes, evolving in isolation over time.

“For biologists, visiting the Galapagos is a dream come true,” remarked Ezra Menderes, a graduate from San Francisco State University and co-author of the study. “There’s still so much to uncover within these well-studied ecosystems.”

This research not only clarifies the status of this magnificent bird but also contributes to a broader understanding of the evolutionary relationships within heron species.

Scientists suggest that what was once perceived as a single, globally distributed species should now be considered as several distinct species, including separate lineages across the Americas, Africa, and Australasia.

“Our ultra-conserved element (UCE) phylogenetic results indicate substantial internal divergence within the genus Butorides, bridging populations from the Old and New Worlds,” the authors noted.

“The UCE-based phylogeny strongly confirms the monophyly of New World herons, including the South American Great Heron, Gray Heron, and Galapagos lava heron.”

The findings, published in this month’s edition of Molecular Phylogenetics and Evolution, significantly enhance our comprehension of avian evolution.

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Ezra Z. Menderes et al. 2026. Global phylogenetic relationships of Butorides herons (suborder: Ardeidae) reveal the evolutionary history and taxonomic status of the Galapagos lava heron. Molecular Phylogenetics and Evolution 220: 108600; doi: 10.1016/j.ympev.2026.108600