The critically endangered white-bellied heron (Ardea insignis) faces extinction due to habitat disturbance from human activities and predation. This makes protecting and conserving the species part of the global efforts to promote biodiversity.
Biodiversity is essential for the processes that support all life on Earth, including humans. Without a wide range of animals, plants and microorganisms, we cannot have the healthy ecosystems that we rely on.
In recent years, the heron’s habitat has been severely disturbed by human activities, and its population has decreased significantly. The white-bellied heron relies on forest and wetland habitats. Both are fast being degraded in all of its range states.
As of 2024, it is estimated that there are fewer than 45 birds in the world. Conservation efforts for the species are limited and fragmented. The white-bellied heron has a uniform dark grey plumage, a whitish belly, and long silvery or whitish plumes on the rear crown and lower foreneck.
In a recent study, researchers from Hosei University, Japan, have successfully hand-reared two white-bellied heron chicks in captivity. This represents a breakthrough for this critically endangered species.
The white-bellied heron is the world’s second-largest heron. It is a symbolic bird for the people of Bhutan and also a typical ‘umbrella species’ that requires a habitat with a vast, preserved environment.
The research was led by Professor Satoshi Shimano who collaborated with the White-bellied Heron Conservation Center in Bhutan, to revive the species through direct intervention.
The scientists overcame previous breeding failures, and the outcome offers new hope for species recovery. This achievement marks a vital step toward restoring wild populations.
The Royal Society for Protection of Nature (RSPN) in Bhutan decided to begin efforts to artificially breed White-bellied Heron outside their natural habitat (ex situ conservation), and the White-bellied Heron Conservation Center (WBHCC) was constructed and began operation in 2022.
The centre, located in the mountainous areas of south-central Bhutan, a six-hour drive from Bhutan’s capital, Thimphu, maintains three white-bellied herons in a large aviary on its grounds. Two of these birds were collected as chicks from wild nests, and the other was rescued as a wounded bird.
Back in 2018, Professor Shimano met a Bhutanese graduate student, Mr. Pema Khandu, who was working to conserve the white-bellied heron. Having witnessed the extinction of the Japanese original strains of the Oriental Stork and the Japanese Crested Ibis, Dr. Shimano volunteered to help.
Professor Shimano contacted other researchers. They concluded that the chick deaths were likely due to hand-rearing techniques rather than genetic abnormalities. To overcome rearing problems, the researchers provided continuous daily online support to Bhutan throughout the breeding season.
Advice included instructing that the bedding material be changed to twigs of a thickness that the chicks could easily grasp. As a result, one of the two chicks showed improvement in its legs and began to grow well.
Through such measures, the scientists are hopeful that, within five to 10 years, when the captive population rises to around 30 individuals, they will release a few into the wild.
The research paper describing the success appears in the journal Science and it is titled “Results of support activities to prevent the extinction of White-bellied Heron (Ardea insignis).”
