Azores Bullfinch

An Azores bullfinch feeds on the buds of a native tree on São Miguel Island in the Azores.
Anne Pinto-Rodrigues

When conservation biologist Jaime Ramos began the fieldwork for his doctoral studies on the elusive Azores bullfinch in 1991, one sound in the island forests excited him the most—the patter of a light drizzle. But there was no rain in sight. The sound was created by the falling fruit husks of the lily-of-the-valley tree as they landed on the leaves below. “It meant that the Azores bullfinch was nearby and it was de-husking the fruit to get to the seed,” says Ramos, of the University of Coimbra, in central Portugal. The sound helped Ramos locate the bird in the dense forest and observe its foraging behavior.

At that time, very little was known about this passerine bird endemic to São Miguel Island in the Azores, an autonomous region of Portugal in the Atlantic. Ramos had some colleagues at the University of the Azores who were aware that this difficult-to-observe bird was restricted to a small patch of native forest in the vicinity of Pico de Vara, the highest point on São Miguel. The Royal Society for the Protection of Birds in the United Kingdom had also been monitoring the bird and estimated the population size of the Azores bullfinch to be at an alarmingly critical level of around 100 breeding pairs.

Ramos’ doctorate was focused on getting a better understanding of the feeding, nesting and other behaviors of the bird. He went on to publish a 1995 study in Biological Conservation on the diet and habitat preferences of the Azores bullfinch, which became crucial for the bird’s conservation. Ramos’ work, and that of other researchers after him, helped show that the bird was a disperser of the spores of several native fern species and, hence, plays an important role in the natural regeneration of the forest.

At the time, the bird was in deep trouble. Following centuries of declining population, in 2005 the International Union for Conservation of Nature (IUCN) listed the Azores bullfinch as “critically endangered.” This earned it the distressing epithet of “Europe’s most endangered passerine bird.” But since then, nearly two decades of conservation efforts focused on habitat restoration have helped the species make a promising recovery. And the comeback of the Azores bullfinch not only is a source of pride for the local community but also draws researchers and tourists from around the world who are interested in the bird and its conservation success.

Back in the 19th century, the chubby bird, known locally as priolo, was hunted down by farmers who considered it a pest in their orange orchards. (Flocks of the birds often ate the young buds of the tree.) Human activities, including agriculture and the commercial planting of non-native Japanese cedars used for buildings and boats, also led to the destruction of the bird’s natural habitat—a subtropical laurel forest. Furthermore, introduced plant species like the Australian cheesewood and the Chilean rhubarb spread across large swaths of land, edging out native vegetation and reducing food and habitat for the Azores bullfinch.

As the first person to formally study the ecology of the Azores bullfinch, Ramos made many observations that helped shape the conservation plan of this highly endangered bird. He found that for the majority of the year the bird feeds on the native plant species found in the forest. Ramos observed that the primary food of the bird in spring are the sugar-rich buds of the endemic Azorean holly. During autumn and winter, the spores and fronds of several native fern species form a large part of the bird’s diet. During winter, Ramos placed bird feeders on the outskirts of the forest to see if the bird would eat from them, but the effort failed, as the bullfinch showed no interest. “It has no other alternatives,” Ramos says. “Hence, it is confined to the area with native vegetation.”

Based on Ramos’ observations, habitat restoration emerged as the primary mode of preserving the Azores bullfinch. “Conservation efforts needed to be focused on two fronts,” says Ramos. “First, removing exotics and creating conditions that promote the growth of the native plant species, and then planting them. And second, slowly trying to increase the size of the forest in certain areas.”

Since 2003, the Portuguese Society for the Study of Birds (known by its Portuguese acronym SPEA), has been leading a conservation program focused on habitat restoration. With funding from the European Union’s LIFE program and the Azores government, the nonprofit began a five-year project in collaboration with the São Miguel forestry department to improve the quality of the forest by planting native trees.

According to Azucena de la Cruz, a conservation biologist who co-leads all of SPEA’s Azores programs, the team quickly learned that they needed to plant native trees close together to prevent the entry of invasive plants. For this they would need a large number of saplings. So as part of a second five-year LIFE project they created a nursery to complement habitat restoration. Saplings of 25 native tree species—including the Azorean holly—and herbaceous plants are cultivated in the nursery. Over the past two decades, around 1,000 acres of laurel forest have been restored in the bird’s core habitat in the specially protected Pico da Vara/Ribeira do Guilherme area. The reserve was first earmarked for the bird’s conservation in 1999 and is currently safeguarded under both local and European legislation. More than 500,000 native trees have been planted in this area.

The increased availability of food and nesting habitat for the Azores bullfinch led to a gradual increase in the bird’s numbers. In 2010, with a population estimate of about 1,000 birds, IUCN downlisted the species to “endangered.” In 2016, the organization downlisted the bird again to “vulnerable.” The current population size of the Azores bullfinch is estimated to be around 1,300 individuals distributed across nearly 5,000 acres of suitable habitat in the Pico da Vara/Ribeira do Guilherme area.

“What we’ve been focused on is not just the number of individuals but also on the trend,” says de la Cruz. “The population trend has been stable for the last eight years.”

SPEA is now on the fourth five-year project funded by the EU’s LIFE program. This project has a much broader focus but also includes the conservation of the Azores bullfinch and its habitat.

Despite all the habitat restoration work so far, the bird does face some threats. Invasive mammals, like rodents, are known to feed on the eggs and fledglings of the Azores bullfinch. In areas that have been recently restored or are currently under restoration, the team has placed rodent-specific traps in an effort to control the invasives.

Another threat to the birds, albeit an indirect one, is the damage caused to recently restored areas by large numbers of people who hike or trail run through their habitat.

While weather is not a big concern now, Ramos notes things could change. “But no one can predict a catastrophic event like drought,” he says. “If you have a good habitat—both in terms of size and quality—the likelihood of these events having an impact decreases.”

The biggest challenge, however, is securing continued funding for the long-term habitat restoration and maintenance work. Knowing that the Azores wants to focus on nature tourism in the future, de la Cruz remains hopeful. “You cannot have nature tourism if you don’t preserve your biodiversity,” she says.

That’s why, alongside habitat restoration, SPEA also prioritized public outreach efforts. In 2007, the organization inaugurated an interpretation center for the bird, the Priolo Environmental Center. Seventy-two-year-old João Mendonça was one of the people who helped with its construction. “When I was younger, we didn’t think about the bird at all,” Mendonça says. “We only focused on our work. Now, everybody cares about the bird and wants to see it.”

Subsequently, the nonprofit developed a comprehensive education and awareness program for school students, customized to each age group. To date, more than 30,000 school students from the island have participated in the education program, which covers several environmental and conservation issues.

SPEA is seeing the impact of its outreach work. “People now feel a bit more connected to the bird, even though many have still not seen it,” de la Cruz says. “And if the conservation efforts stop, they would be concerned.”

Mendonça’s nephew Luis Pacheco leads tours at the environmental center. According to him, not only do school students from the island and tourists from mainland Portugal visit the center, but university students from as far away as California, Germany and Malta have also paid a visit.

“We feel so proud when people come from all over the world to see the bird,” Mendonça says.

De la Cruz agrees. Given the global despair about vanishing species, she wants the conservation success of this small bird to have a far-reaching impact. “We hope by hearing the story of the Azores bullfinch, people are inspired to adapt it to species in their own land,” she says.

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