Wetland wildlife paying dearly for the deadly ‘China Duari’
Even after being discarded, these traps submerge and act as ghost nets, killing aquatic biodiversity of all sorts
Last week, while birding near Mirertek in Gerua, Savar, a strange sight caught my attention — a serpentine head peeping through a fish trap lying by the bank of a wetland. A close inspection felt necessary. My fellow bird watchers and I approached the scene.
An appalling sight hit us.
More than a dozen common, harmless aquatic snakes were trapped, some already dead and stiff. Others, although severely weakened, were still writhing. Entangled in the fine mesh of the traps, some had their bellies ripped open. Worse still, whenever these ill-fated snakes peeked their heads out of the traps, they turned into live targets; some kids were trying to score points by throwing pebbles at them.
We counted eight still-alive painted keelbacks, known for their bright burgundy scales and canary yellow side stripes. The chequered keelbacks and smooth-scale water snakes were not lucky — they died trapped inside under the baking heat, dehydrated. Both species have base olive-green colours. Chequered keelbacks have darker Burberry patterns all over. Smooth-scale water snakes have bright yellow underbellies. In Bangla, all three species are known as 'Dhora shaap'.
Keep updated, follow The Business Standard's Google news channel
The trap was a new variant, made of bamboo and rattan weave. Although local hand-made traps were popular until recently, these new traps imported from China have taken over the fishing scene, displacing a whole cottage industry of trap-making in the process. These Chinese fishing traps are foldable and come in rows of inter-connected sets of traps. They are locally called China Duari and are often sold as China Magic Ring Net on online marketplaces.
This horrible scene switched our photo op to a rescue op. A group of people from a nearby madrasa shared similar feelings and offered their help. After searching for hours, we finally found the owner of the net. The net owner was not as moved as we were. The scene was not new to the person. "Almost in every round, they die by the dozens," we were waved off. "And it has been going on for over a month," his voice was indifferent.
The severity of the problem that the wetland ecosystem is dealing with shocked us. This means that hundreds of these innocuous snakes had died for nothing — collateral damage for simply following the trapped fish, crabs, and frogs as easy meals. The locals were also very keen about killing any snakes on sight.
Painted keelbacks are uncommon in these urban wetlands. Information on its ecology is also poor. The discovery of this site shed new light on snake activities and their presence in Savar upazila. During rainy seasons, these snakes spread across the floodplains of the Dhaleshwari River.
When the water level drops, locals fit China Duari in narrow channels, specifically cut to steer water flow and the fish that follow along. Fish, snakes and other aquatic animals then get caught in these nets.
China Duari are non-biodegradable, plastic-made, deadlier, functional even after disposal, and infamous for sapping out wetlands. Slack law enforcement has let it spread all over Bangladesh, further endangering the ever-threatened biodiversity of the country's wetlands. They bear striking similarities with monofilament gill nets in having extremely fine mesh. Such gill nets are contraband in Bangladesh.
These traps are made for shallow waters. The nets are usually 50 to 100 feet long, separated into roughly foot-long square boxes, which can operate independently. These are cheaper than local hand-made traps and easy to discard. Once discarded though, the traps eventually submerge and act as ghost nets, killing aquatic biodiversity of all sorts. Armed with the finest types of noose, the traps can catch even centimetre-long fish fries.
Although China Duari is not officially banned in Bangladesh, its mesh size (measurement of the distance between each knot in the net) is much lower than the approved size, which is 4.5 centimetres in width. Yes, they can lead to big hauls, but are we killing the golden egg-laying goose in the process?
The government must take action and establish strict laws against the use of this trap. Various nature organisations can also come forward to save our wetlands from this new threat, before it is too late. We must not forget that human lives depend on the wetlands and we need these habitats to survive. The creatures of the wetlands create a self-sustaining ecosystem that maintains the habitat on which thousands of people are dependent. In turn, these ecosystems also help store and capture greenhouse gases from the atmosphere, cleansing the air that we breathe into our lungs.
The loss of creatures at such high numbers will lead to the death of a complete ecosystem.
We released the snakes, knowing that they might face the same danger later that very same day. With all the snakes and frogs caught, and all the fish heavily harvested, will there be room for wetland birds, fishing cats, or otters? Will there be room for us? Will we ever be able to grasp the bigger picture in time?
