The critically endangered bird species, White-Bellied heron, count in Bhutan has dropped down to 27. Last year the count was at 28.
The entire world only has around 200 to 250 of these rapidly declining birds left.
Despite the numerous initiatives taken by the Royal Society for Protection of Nature (RSPN), in conserving the critically endangered bird, the casualty rate has always remained high due to natural and manmade causes.
White-Bellied heron population is hugely concentrated in the Punatshangchu valley in Bhutan, but a few of the birds can also be found in Berthi, Zhemgang.
Conserving the small stretch of the White-Bellied heron habitat along the Punatsangchu river basin is essential to its survival. Therefore, with infrastructure and expertise assistance from the Punatshangchu hydropower project, RSPN has intitated and proposed for a breeding site for the critically endangered bird.
RSPN is all set to begin with the captive breeding or artificial rearing of the birds. According to the Research Head of White-Bellied heron (WBH), Rebecca Pradhan, RSPN has been working on a long-term conservation plan. The preliminary research on WBH habitat ecology, feeding and breeding ecology has been completed.
She said that the design and cost estimation of the breeding site are scheduled to be complete soon. RSPN had the assistance from experts to study the breeding site and design. The research team tested over 353 streams in various locations around the country to ascertain the conditions that are fit for the adaptability of WBH.
The team found the current proposed site near Punatsangchu project and Berthi as most appropriate for the birds to survive in. RSPN is also looking for suitable places with no disturbances to release the matured WBH that are bred in captivity. Overhead cables, dams, hunting or persecution and climate changes pose serious threats to the critically endangered bird.
As for the artificial breeding site between the two mega hydropower project sites, Rebecca Pradhan said that despite huge construction works and disturbances, there is still one place where conservation of the critically endangered bird can take place.
“Captive breeding is one middle path towards conservation of the endangered bird,” Rebecca Pradhan said.
As for the challenges faced in artifical breeding of WBH, Rebecca Pradhan said that RSPN had made a breakthrough when they first reared a WBH chick in captivity in 2011.
She said that rearing of WBH begins from laying of eggs in early March, closely watching the eggs for solidification which entails 30 days of close watching and 73 days of rearing the eggs in the incubator. After 134 days of rearing, the birds are matured enough to be released in the wild.
RSPN has been carrying out WBH population census regularly for the last 13 years and their census has revealed that atleast 12 WBH juveniles are produced every year. The number of WBH in the country has,on an average, remained constant during the entire survey period.
RSPN has counted 14 individuals in their maiden survey in 2003, and since then the WBH population has seen a steady rise in the country until 2009 where RSPN recorded the highest count of 30 WBH in 2008 and 2009.
However, the number declined in the next 4 years as the 2013 RSPN survey was able to count only 20 WBH, a drastic decline of 10 birds. However, in the survey conducted on February 24 to 28, it recorded a rise with two more individuals from the previous year.
Although the mortality rate of the critically endangered bird has been significant over the years, Bhutan still has a comparatively decent number of WBH, thanks to the aggressive conservation effort pursued by RSPN in collaboration with Department of Forest and Park Services (DoFPS).
Apart from the existing conservation effort, RSPN is also carrying out various activities which include community awareness, long term conservation strategies and a“White-bellied Heron Recovery Plan” project.