BirdsCaribbean brings you highlights from the Journal of Caribbean Ornithology in our feature “Just Published in JCO.” Here, Zoya Buckmire, the Lead Copy Editor for the Journal of Caribbean Ornithology, details the search for an elusive birdsong—and how these melodies are challenging long-standing biases in ornithological study.

The fact that male birds sing is common knowledge to many. But did you know that female birds can also sing? This behavior is more common in tropical species, and is underrepresented in the literature due to a temperate bias in scientific study. In Puerto Rico, the females of several species have been documented singing, including the now-endemic Puerto Rican Euphonia (Chlorophonia sclateri). In their recently published article, Miguel Costas Sabatier and Alejandro Ríos-Franceschi describe the intricacies of female song in this species, highlighting the importance of addressing biases in research and sound recording to get a fuller picture of avian communication. We asked the authors a few questions to get the behind-the-scenes scoop on their research.

But first, about the Puerto Rican Euphonia:

This dazzling endemic was formerly part of the Antillean Euphonia complex, which was recently split into three species: namely the Hispaniolan (C. musica), Puerto Rican (C. sclateri), and Lesser Antillean Euphonias (C. flavifrons). Euphonias are frugivores and uncommon residents fond of forested habitats. Each of these species has gorgeous blue-green and yellow-orange plumage and a captivating song. In 2023, in recognition of their plumage, size, and sexual differences (or lack thereof), the three species were separated, adding two new endemics to the total of Caribbean avifauna. Some genetic and molecular work has been undertaken to clarify the relationship among these species, but much more remains to be done. Dr. Sheylda Diaz, another Puerto Rican biologist, has published the genome of the species with the company Iridian Genomes using specimens in the Field Museum of Natural History, and more connections have been made to sequence the genome of the other Caribbean euphonias.

The male Hispaniolan Euphonia has a dark blue throat and an orange underside and rump. (Photo by Joshua Covill, ML548852851)

Male Lesser Antillea on Dominica. (Photo by David Hollie, Macaulay Library-ML595435561)

A male Puerto Rican Euphonia. (Photo by Jack Rogers ML632441868)

A colourful collaboration

Dr. Diaz’s work actually went hand in hand with Miguel and Alejandro’s research. In an office conversation between Dr. Alejandro Ríos-Franceschi and Dr. Diaz in 2022, they decided to work on collecting evidence for the reclassification of the species, with Alejandro focusing on the behavioural aspects, including song, and Sheylda tackling the molecular work. Their aim was to “analyze species vocalizations at each island to complete a description of the vocal repertoire to complement the molecular analysis” (A. Ríos-Franceschi); and indeed bioacoustics are a critical part of understanding species, especially our unique endemics. Miguel Costas, an undergraduate student at the time who was interested in research but had no prior experience, was taken under Alejandro’s wing (pun intended) to assist under a scholarship, the Puerto Rico Louis Stokes Alliance for Minority Participation (PRLSAMP). And so, this work began.

Searching for a song

However, as you can imagine with a relatively uncommon species like the euphonia, fieldwork was no easy feat. The team had difficulty finding birds to record in Puerto Rico, despite days spent searching the Guánica State Forest, and sample sizes were small. But good things come to those who wait! Alejandro praises Miguel’s patience, saying his student’s “perseverance in the field was rewarded with the female recordings, which to our knowledge had not been recorded or published.” The recordings were even doubted initially by colleagues who dismissed it under the common assumption that ‘only male birds sing’, but Miguel was determined that he had found something special and luckily—he had proof.

Miguel recording Puerto Rican Euphonia calls and songs in Guanica State Forest.

A sampling site in the Guanica State Forest, Puerto Rico.

Miguel recounts when he spotted the singing female: “The day [on] which I recorded the female really stands out to me, it was just as the field sampling was about to end that I noticed the pair. I quickly started recording them both as they gleaned from a tree and moved across the trail. As soon as the male left the area, I remember training my eyes on the female and then when she started singing left quite the impression on me. I remember calling Dr. Alejandro Ríos as soon as I left the forest to let him know what I [had just] seen.”

So it is confirmed: female birds can and do sing. The recording of our lady of the hour is available on Macaulay Library for all to admire (ML609987555), and the authors went a step further in analyzing and comparing her song to a male recorded a few days earlier at the same site.

Why does this all matter?

Research is, unfortunately, inherently biased. The temperate bias in researchers and funding means that tropical regions and species are understudied, making temperate behavior the default assumption applied to all species. Song production between the sexes differs among geographic regions, and tropical female birds are more likely to sing than their temperate counterparts. This temperate assumption then biases research towards male birds, perpetuating the lack of data on female song. The authors’ hope is that this record of the Puerto Rican Euphonia will help reduce these biases in future research. As Miguel said, “I hope that my research will mean more people recognize female song. I also hope that people pay more attention to the natural history of birds on the island.” This record is a step in the right direction.

Alejandro plans to keep the momentum going, and to keep inspiring students like Miguel, who has since become a graduate student at the University of Puerto Rico (UPR), to get involved in ecological research. “The lack of funding for doing ecological research is a major challenge, plus the budget cuts at the UPR System. That is why programs such as PRLSAMP, and organizations dedicated to conservation are important to incentivize students to do research.”

This article is a perfect example of the JCO’s mission to publish and promote natural and life history information of our understudied regional birds, especially when that research is done by emerging researchers. Filling knowledge gaps about our endemics and helping budding ornithologists get both experience and exposure? That’s what we’re all about. BirdsCaribbean also provides upfront support for researchers, both technical and financial, allowing even more conservation-driven data to be collected for our species. See our recent blog post announcing the 2025 awardees of BirdsCaribbean’s small grants. 

Recently, significant amounts of federal funding—already committed through grants to federal partners—have been canceled or indefinitely paused. Without these resources, we face serious threats to continuing our vital work and the momentum we’ve built with our incredible partners. In the face of these unprecedented challenges, your contributions are more important than ever to keep these initiatives going throughout the region. Please consider donating today.

The Journal of Caribbean Ornithology is a peer-reviewed journal covering all aspects of ornithology within the Caribbean region, publishing in English, Spanish, and French. We welcome manuscripts covering the biology, ecology, behavior, life history, and conservation of Caribbean birds and their habitats. The JCO also publishes conservation reports and mentors inexperienced authors to help them develop their manuscript for publication. The JCO relies on donations to keep all of our publications free and open-access. Support our non-profit mission and give a voice to Caribbean ornithologists and their work by becoming a supporter of JCO.