A species extinct in the wild for decades is preparing to come home, thanks to a global conservation effort.
Explore the JourneyIn the dense woodlands of Socorro Island, a peculiar silence has lingered for over half a century. It is the absence of a coo that once echoed through the undergrowth, the absence of a cinnamon-brown bird that was known for its remarkable tameness.
The Socorro dove (Zenaida graysoni), a species found nowhere else on Earth, was declared Extinct in the Wild in 1972, a victim of habitat destruction and introduced predators 1 4 . Yet, today, the rustle of feathers is returning, not on the island itself, but in the carefully managed aviaries of conservation zoos across the world.
This is the story of an international mission to pull a species back from the abyss, a story where every hatching chick represents a triumph of hope and a step closer to reversing a decades-old tragedy.
Socorro Island, Mexico
Since 1972
200-209 birds
By 2030
Socorro dove once lived a secluded life on Socorro Island, a volcanic landmass located about 400 kilometers off the west coast of Mexico 4 . These birds evolved in an environment with no natural predators, which made them remarkably trusting and tame 4 .
Every Socorro dove alive today, from the UK to North America, is a descendant of those few founding birds collected in 1925 4 . This tiny population has been sustained for almost a century through dedicated captive breeding programs in zoos.
Global Distribution Map
(Interactive map showing zoo locations)The survival of the Socorro dove hinges on a coordinated international effort, including breeding programmes like the European Endangered Species Programme (EEP) 5 .
Recent successes have provided a significant boost to this endeavor. In 2025, Chester Zoo celebrated the hatching of eight chicks, while Whipsnade Zoo in Bedfordshire welcomed its first-ever Socorro dove chick in late August 1 4 .
The chicks cared for at ZSL's Whipsnade and London Zoos alone are believed to account for almost 5% of the species' entire global population 1 3 .
"Our Socorro dove chick is doing well and growing quickly. It's already taken the first step towards independence by fledging the nest."
| Zoo | Number of Chicks | Year | Significance |
|---|---|---|---|
| Chester Zoo | 8 | 2025 | A major boost to the captive population 4 |
| Whipsnade Zoo | 1 | 2025 | The first-ever Socorro dove to hatch at this zoo 1 |
| London Zoo | 9 | Recent years | Part of a sustained breeding effort 1 |
| Paignton Zoo | 2 | Recent years | Successfully fledged as part of the EEP 5 |
One of the fascinating aspects of Socorro dove behavior that has been observed in captivity is their unique parenting style. Unlike many other birds, the male Socorro dove takes over the majority of chick-rearing duties after the initial phase.
"The females will raise their chicks for a while and then get ready to mate again... When that happens, the fathers take over with the older chicks, feeding them and caring for them."
This behavior is believed to have been an adaptation to their original island home, where short breeding windows between storms and heat waves made efficient reproduction essential 4 .
Father doves take over chick-rearing duties
Breeding the birds in captivity is only the first step. The ultimate goal, championed by the Socorro Dove Project, is to return the doves to their native island 3 .
This ambitious initiative is a collaboration between ZSL (the conservation charity behind Whipsnade and London Zoos), key partners in Mexico, Frankfurt Zoo, African Safari, and other zoos within the EAZA and AZA networks 3 .
The project has a clear target: to reintroduce the Socorro dove to Socorro Island by 2030 8 .
For reintroduction to be successful, the threats that wiped out the doves must first be eliminated. Significant progress has already been made.
The invasive sheep, which caused severe habitat loss through deforestation, were completely removed from Socorro Island by 2010 4 6 .
This has allowed the island's native vegetation to begin a slow but steady recovery 4 6 .
The next major challenge is dealing with the feral cats that originally preyed on the trusting doves 4 6 .
| Tool/Resource | Function in Conservation |
|---|---|
| International Breeding Programmes (EEP/AZA) | Coordinates breeding across zoos to maximize genetic diversity and population health 3 5 |
| PCR and Microscopy | Used in tandem to screen for blood parasites in both captive and wild bird populations, assessing disease risks |
| Habitat Restoration | Removal of invasive sheep and replanting of native vegetation on Socorro Island to restore the dove's original ecosystem 4 6 |
| Invasive Species Eradication | The ongoing removal of feral cats from Socorro Island, the primary predator responsible for the dove's extinction 4 6 |
Reintroducing a species after a long absence requires careful planning and a thorough assessment of the risks it will face. One of the most significant threats is disease. A crucial scientific study was undertaken to screen the avifauna of Socorro Island for blood parasites, specifically to understand what the Socorro doves would be exposed to upon their return .
Researchers focused on the bird species that the returning doves would encounter, namely the Socorro ground dove and the mourning dove . They captured these birds and collected blood samples. Each sample was analyzed using two complementary techniques:
This dual approach ensured a comprehensive analysis. For comparison, captive Socorro doves in zoos were also screened for these parasites.
The study revealed a high prevalence of parasites in the island's current bird population.
Phylogenetic analysis confirmed that the Socorro dove would be exposed to these native Haemoproteus lineages upon reintroduction. While these parasites are common in wild birds, their impact on a population that has been in protective captivity for generations is unknown and requires careful monitoring.
| Bird Species | Sample Size | Infected with Haemoproteus spp. | Infected with Plasmodium sp. |
|---|---|---|---|
| Socorro Ground Dove | 23 | 17 (74%) | 0 |
| Mourning Dove | 25 | 23 (92%) | 1 (4%) |
| Northern Mockingbird | 21 | 3 (14%) | 0 |
The story of the Socorro dove is a powerful testament to the role of zoos and international collaboration in preventing extinction.
What was once a tragedy—the loss of a unique species from its island home—has been transformed into a beacon of hope. The recent breeding successes are not just about adding numbers; they are about building a robust, genetically diverse population that can one day weather the challenges of life in the wild.
"Each hatchling is a step forward for the survival of a species that would have otherwise been lost forever."
The path forward is not without obstacles. The presence of feral cats and potential disease threats like avian malaria are serious concerns that must be mitigated 4 . Yet, the progress is undeniable. The habitat is healing, and dedicated aviaries already stand on Socorro Island, waiting for their inhabitants 4 .
The continued success of this program will not only return the Socorro dove to its skies but will also provide an invaluable blueprint for restoring the dozens of other species that currently exist only in captivity. The coo of the Socorro dove may soon fill the woods of Socorro Island once more, a sound signaling not just a return from the void, but a second chance.
From extinction
International effort
Ecosystem recovery