The Javan pied starling (Gracupica jalla) was once common across the Indonesian island of Java, but has now disappeared from the wild, thanks in large part to the songbird trade.
A new study that chronicles the bird’s decline points to historically unsustainable rates of harvest of starlings from the wild, including fledglings.
The study authors recommend captive breeding to reestablish genetic diversity in the species for eventual reintroduction of starlings into the wild.
Keeping songbirds is a culturally ingrained pastime in Indonesia, with even the country’s president partaking, which activists say must be addressed with awareness building.
The Javan pied starling (Gracupica jalla) is a captive in its own home. Thousands of these endemic songbirds once congregated in the safety of tall trees to roost after spending their days feasting on insect larvae. Today, however, the Javan pied starling is conspicuously absent from the wild, yet readily found caged in markets and houses across the Indonesian island of Java.
In a recent study, researchers Bas van Balen of Dutch organization Basilornis Consults, and Nigel Collar of BirdLife International document the insidious disappearance of Javan pied starlings from across their native range. Like a pair of detectives, Van Balen and Collar combed through evidence to explain the starling’s disappearance. What they found were two possible culprits: overharvesting for the trade, and overuse of pesticides that kill the songbird’s prey.
Java, the most populous island in the Indonesian archipelago, is known for its remarkable biodiversity and high species endemism. Overexploitation of natural resources, however, is transforming the Javan landscape and threatening indigenous flora and fauna.
“Fifty to hundred years ago the Javan Pied Starling was one of the commonest birds in Java’s farmlands,” Van Balen said in an IUCN press release. “Now, no wild birds are known to survive in the wild. Just a few occasional [escapes] can be seen.”
Drastic declines in native songbird populations across Asia, driven by unsustainable harvesting for the pet trade, have led experts to declare an Asian songbird crisis. In response, the IUCN formed the Asian Songbird Trade Specialist Group (ASTSG), a team of experts dedicated to researching and conserving the region’s songbirds.
Since its inception, the group has identified 44 bird species threatened by the trade; eight of these, including the Javan pied starling, are critically endangered. Yet the ASTSG is concerned that some birds are being overlooked.
“There are a number of [Asian songbird] taxa not universally recognized as full species,” David Jeggo, ASTSG chair, told Mongabay. “As a consequence, they are not on the [IUCN] Red List as threatened, but are very close to extinction.”
Meanwhile, keeping wild-caught birds as pets remains a cornerstone of Javanese culture, with some estimates claiming there are more birds in Indonesian households than in the wild.
“Keeping caged songbirds is a centuries-old tradition among Javanese,” Marison Guciano, the executive director of FLIGHT, an Indonesian organization fighting to protect native songbirds, told Mongabay. “Now, keeping birds in cages is not only a Javanese tradition, but has also been imitated by most Indonesians. An estimated 13-14 million people in Indonesia have a hobby of keeping birds in cages.”
Singing competitions play a major role in driving the demand for wild-caught songbirds. Participants enter their prized pet birds and stand at a distance yelling and whistling for their bird to sing louder as judges listen and award points. These contests are a popular — and incentivized — Indonesian pastime, according to Guciano. Thousands of singing contests are hosted every year and winners receive coveted cash prizes.
“Ironically, many politicians, government officials, and public figures organize songbird contests to increase their popularity,” Guciano said.
Indonesia’s president, Joko Widodo, is himself an avid collector of songbirds, which he enters into singing contests. In 2018, he even offered to buy a prize-winning bird for the equivalent of $41,000.
The prevalence of singing contests across social classes complicates the already difficult issue of regulating the songbird trade. Many Indonesian songbirds are not legally protected, so the trade in these species cannot be prosecuted, Guciano said.
Accounts of poaching described by Van Balen and Collar offer clues about why the practice was unsustainable. One report tells of nests emptied by poachers before the birds even fledge. Another recounts how hundreds of Javanese trappers would team up and capture thousands of birds at a time.
Likely exacerbating the starling overharvesting problem was the widespread use of agrochemicals in Javan pied starling habitat, Van Balen and Collar say in their paper. Evidence suggests there was a significant increase in pesticide use on farms in the decades of Javan pied starling decline — so much so that many soil invertebrates like earthworms were wiped out.
With a major food source nearly eradicated, Javan pied starling populations may have shrunk. All the while, poaching pressure kept pecking away at their declining populations.
Whether the Javan pied starling disappeared as a result of the songbird trade, pesticides, or a combination of the two, the bird’s absence went unnoticed until it was almost too late. Van Balen and Collar see this as a case of “shifting baseline syndrome,” where people have trouble perceiving changes in their environment as they’re happening. Only after the fact, with the benefit of hindsight and years of data, is it evident that declines were happening.
Experts, including Van Balen and Collar, advocate for captive breeding of Javan pied starlings to reintroduce the species into the wild. But they caution that the execution of such programs will likely be difficult.
“There are major downsides to captive breeding,” Collar told Mongabay. “It selects for domesticity. This renders birds less fit for living in the wild … We have no idea how many generations [of] Javan Pied Starlings have been in captivity … The genes for wild survival have to be selected back into the population.”
Van Balen, however, said captive breeding and reintroduction is a worthwhile pursuit to save the species.
“A successful reintroduction will greatly enrich the Javan and Balinese environment,” he told Mongabay, “as this was once one of the most common birds [and] so well adapted to rural and urban habitat.”
Captive breeding and reintroduction may not just save the Javan pied starling from extinction, but it could also restore valuable ecological functions to local ecosystems. Based on records of their diets, the starlings may be effective pest control agents, Collar and Van Balen say in their paper.
Successful reintroduction could kick off a feedback loop beneficial for both the birds and the environment by reducing pests and the need for agrochemicals, the IUCN press release says.
For his part, Guciano says he envisions a cultural shift as essential to tackling the Asian songbird crisis. Through outreach and education, FLIGHT aims to raise awareness about the ecological role of native birds and the consequences of overharvesting them from the wild.
“The demand for songbirds must be reduced by building public awareness that the place for songbirds is in nature, not in cages,” Guciano told Mongabay. “Let the birds fly free in nature [and] carry out their ecological functions to sow seeds and maintain the balance of the ecosystem.”
Van Balen, S. B., & Collar, N. J. (2021). The vanishing act: A history and natural history of the Javan pied starling Gracupica jalla. Ardea, 109(1), 41-54. doi:10.5253/arde.v109i1.a1