An attempt by villagers and wildlife enthusiasts to save a rare fish from extinction is a rare ray of hope amid the gloom of the gradual loss of biodiversity.
Last week, ignoring blood-sucking leeches, dozens of volunteers got their hands dirty and pants wet on the muddy banks of the Galapitamada stream, known to be the only habitat of the critically endangered Bandula Barb. They cleaned the stream and planted ketala aquatic plants on the edges of the stream to enhance the breeding habitat and give much-needed protection for this small fish.
Bandula Barb (Pethia Bandula) is one of the rarest and most endangered fish in Sri Lanka as it can only be found in a 2.5km stretch of a small stream in the Kegalle district. Their present count is just over 1000, so the threat to their existence is enormous.The habitat rehabilitation work held last Sunday was organised by the International Union of Conservation of Nature (IUCN) with the assistance of the Toyota Environmental Fund. This two-year project began in 2013 in accordance with the Bandula Barb Recovery Plan drafted by the Sri Lanka Biodiversity Secretariat of Ministry of Environment in 2007, looking into empowering the villagers to conserve the fish as the area is totally outside any protected areas. Habitat enrichment and the introduction of the fish into other habitats are part of this Conservation Plan, being implemented under the guidance of Professor Devaka Weerakoon.
The data on the drastic decline of Bandula Barb emerged through research carried out by Hasula Wickremasinghe in 2003 as part of her MSc research. In 1991, the fish “catch rate” – a technique used to measure fish population – as 15-100 but in 2003 it sank to 0–5. This is an 80 per cent decline of the population. Ms. Wickremasinghe and Sampath Goonathilake, prepared the Bandula Barb recovery plan under the guidance of Prof. Weerakoon.
In May 2013, a total of 598 Bandula Barbs were found. This number increased to 1073 in December that year, raising hopes that the species can recover but more work has to be done to get the population stable, according to experts.
The volunteers of the Aquatic group of the Young Zoologists Association (YZA) were the leading force behind last Sunday’s activities. The team planted native trees along the stream bank together with the participation of the villagers. As the climate in the area is expected to be drier with repercussions of climate change, it is hoped these trees could provide a lifeline to the stream, keeping it from going dry.
This stream in which the Bandula Barb lives flows between paddy fields and rubber estates so the agro-chemicals used in the paddy fields have become the main threat to their survival.
“So the IUCN tried to convince the villagers of the importance of turning to organic farming. We linked them with an organization supporting organic paddy cultivation and we are happy that the paddy fields adjacent to the stream areas turned into organic cultivation areas where agro-chemicals are not used,” said Naalin Perera, IUCN Programme officer, Biodiversity, pointing to the lush paddy fields.
The IUCN also organized a workshop on freshwater fish for the village youths. This included a field visit to Kithulgala to observe the freshwater fish and methods of observation as well as techniques of counting.
The village youths became involved in the counting of number of Bandula Pethia in the stream in a survey conducted in December last year. A total of 1073 fish were recorded, an encouraging result for the conservation team. Mr. Perera also commended the enthusiasm shown by the village youth on learning more details about the freshwater fish.
The IUCN team has also reintroduced a population of Bandula Pethia to an isolated area close to Galapitamada. A wall was built under the project to prevent Bandula Barb being washed into the nearby paddy fields during heavy rains. The IUCN hopes the the effort to save the Bandula Barb from extinction will be successful.
The Bandula Barb was discovered in 1991 by Rohan Pethiyagoda. Communicating through email, the expert on fish reveals that he first saw the Bandula Barb in an aquarium at the home of Rodney Jonklaas around 1987. Mr. Jonklass named the fish Bandula Barb because these specimen were given by Ranjith Bandula, an ornamental fish collector.
Mr. Jonklass thought it was a subspecies of the fish we now know as Pethia reval, or that it was a hybrid between Pethia reval and Pethia nigrofasciatus, the so-called Bulath Hapaya. Both those species too, occur in the same Kelani River basin as the Bandula Barb.
Mr. Pethiyagoda said no one knew the reasons for this fish having such a narrow ecological niche. “It is certainly unusual given that there is apparently nothing to prevent the species from dispersing further down the stream,” he added.
‘At first, we were suspicious’
“We are proud to have Bandula Pethia in the village as the fish made our quiet hamlet a famous place. Lots of people and collectors visited our village after getting to know the importance of this fish, but we haven’t allowed anyone to steal the fish,” said Ranjith Amarasiri, a villager who works with the researchers. “Even our children are protective of the fish and don’t allow outsiders to take them out,” Ranjith said, sharing a story of how a village child protested when outsiders tried to take away a specimen of Bandula Barb.
It is the vigilance of the villagers that helped the Bandula Barb to survive through these difficult times where exploitation, invasive species and pollution threatens Sri Lanka’s freshwater fauna.
“When I first visited Gapapitamada in 1987/88 the local people had no idea this fish existed or that it was special,” said Rohan Pethiyagoda who described the fish scientifically.
“They were initially strangers and didn’t say anything to us,” said Sarath Weerakkody, a villager who initially helped to build the link between villagers and conservationists. “When they combed the stream and started to catch fish we grew suspicious. Some youth who became angry and even threw stones at these researchers. But they came and explained to us about the fish and we also began to realise the importance of the fish,” said Mr. Weerakkody.
The effort of the villagers of Elpitiya, Hapudoda and Rabbidigala to prevent the extinction of the Bandula Barb could be a unique conservation model to protect Sri Lanka’s biodiversity.