This is part two of the story of this exceptional sighting. See part one for the adventures that lead to the sighting.
A Significant Sighting
My first inkling of how the significance of the sighting was when Andrew Vallely (author of The Birds of Central America) commented that he thought this might be a new farthest north record for the species, which we helpfully confirmed with a copy of his book when we got back to shore.
A few days later, I received a text message from Serge Arias, a professor at the University of Costa Rica (UCR) and head of the PLUMARE project monitoring seabird populations in Costa Rica. He was finishing work on a book “The Birds of Isla del Coco” and wanted to see if I’d be willing to contribute some photos from this recent outing.
I was happy to contribute and we got to discussing the significance of the sighting. He also thought it was a new northernmost record for the species. Under that assumption, I started writing up a note a few months later. I knew of the previous sighting from near Isla del Coco several degrees of latitude to the south and when referencing the paper on that sighting I was surprised to find a statement that the bird was found in “This species has been reported regularly over offshore waters of Middle America (Spear, Ainley, Nur, & Howell, 1995)”. Likewise, the map from BirdLife International showed the range of the species extending up into central Mexico.
I was having difficulty finding any concrete sightings to back up these assertions. The groundbreaking census work performed in the 80s and 90s by Spear et. al didn’t provide specific sightings and used very large census blocks spanning 5 or 6 degrees of latitude and longitude. Adding to the confusion, prior to 2002 both Hawaiian and Galapagos Petrels were treated as subspecies of a single species, Dark-rumped Petrel.
Serge offered to help me dig into this confusing set of reports and contacted some colleagues in Mexico. They were equally perplexed, finding the species listed on the country list for Mexico but finding no actual records of it. Additionally in the last decade several Hawaiian Petrels had been documented in Mexican waters, farther south than that species was expected to range. It seems an old Dark-rumped Petrel was simply being assumed to have been a Galapagos Petrel when, especially given recent records in Mexico, it could have been a Hawaiian Petrel.
I also managed to contact Knut Eisermann who compiles the list for Guatemala who informed me that the species should be treated as hypothetical for Guatemala. There was an old report without documentation from 300 km offshore of a Dark-rumped Petrel as the basis for its status in the country.
As Serge and I consulted with these experts in pelagic birding, we came to the conclusion that without specific sighting records from the census data and no photos to determine which species the historical birds from Mexico or Guatemala belonged to, that those sightings were unable to be assumed to be one species or the other. They equally could have been vagrant Hawaiian Petrels as they could be vagrant Galapagos Petrels.
Right as we were figuring this out a new southernmost record for the species was also reported in Chile, which added evidence to what one researcher who has been tracking many individuals with satellite trackers told us, that they tended to range south rather than north from the Galapagos Islands.
Conclusions Reached
What started as a simple note on an exceptional sighting had now turned into a lot more research and writing than originally planned! What we could say for sure is that the range of the species is probably not right as currently mapped out. But exactly where it ranges is still in need of further study.
The tracking work published on Move Bank by Carolina Proaño is a fantastic move forward in this, as are individual sightings published to citizen science portals like eBird. While protecting their breeding colonies in the Galapagos is the most important part of their conservation their vast marine habitat also needs protection. The recent note that was published in Zeledonia, the journal of the Costa Rican Ornithological Association, is an important step in compiling the information needed to ensure that protection.
What began as a spontaneous decision to join strangers on a boat grew into something bigger than any of us expected that morning. Our photographs of a single bird cutting through Pacific swells didn’t just add a species to our life lists—they potentially redrew the conservation map for this critically endangered seabird. This is why citizen science and field research matters: important discoveries often happen not only in research institutions or university labs, but in the split second when a passionate naturalist with a camera captures something extraordinary and decides to learn more. For the Galapagos Petrel, critically endangered and still largely mysterious in its wanderings, every unexpected sighting is part of the difference between protection and extinction, making every pelagic trip a potential voyage of discovery that could reshape what we know about this species we’re fighting to save.
