WETLANDS, land covered with water (fresh, brackish, salt, natural or man-made) traverse the continents and in turn host an array of creatures – easily seen or hidden – that go beyond imagination. Go beyond the muck that sucks up shoes with each step to appreciate their economic and ecological importance, as well as their splendour.
Malaysian Nature Society Conservation Division head Yeap Chin Aik delved into the mysterious wetlands and introduced the world of shorebirds last month. Yeap, who has over 10 years of experience in conservation activities, works closely with BirdLife International on updating the status of globally threatened birds (for Malaysia) and several regional bird-related projects. He has published several papers and is one of the compilers of the directory on Important Bird Areas in Malaysia. Currently many wetlands are being degraded or destroyed leaving more species of shorebirds threatened with extinction.
Malaysia is an important link in the East Asian-Australasian Flyway (highway in the sky), which encompasses 22 countries, including among others, Malaysia, Australia, New Zealand, Indonesia, Thailand, China, Korea, Japan and Alaska in the US. Fifty million from 54 species and 250 populations take to the air twice yearly to fly from northern breeding grounds to southern overwintering-grounds. Malaysia’s long coastline, which is mostly covered with mangrove forests and in Sarawak sandflats (sandy beaches), host resident species and winter visitors, in addition they are refuelling centres for the tired avian travellers.
Populations of 45 per cent of all migrating birds have shown a decline and in Asia this dramatically increases to 62 per cent. Why? There are several reasons including the loss of habitat. Populations of migrating birds can be affected by changing land use (for example construction or aquaculture) in summer breeding or overwintering grounds, and resting areas along the migration routes. In addition, habitat loss is also attributed to changing weather patterns associated with climate change that could affect the wetland’s hydrology (wetlands could become drier or wetter).
Migrating shorebirds are sometimes hunted. They are very visible as they feed in large flocks on the mudflats or sandflats. On the plus side, this trait also means that accurate counts of numbers can be obtained and novice birders can see birds. Introduced predators can also cause a reduction in populations.
The rich biologically diverse mudflats of the Bako-Buntal Bay, an approximate 45-minute drive from Kuching, is one of the over 30 Important Bird Areas in East Malaysia and is literally a refuelling station for the tired travellers. The shorebirds consume huge quantities of sea creatures including shellfish, worms and fish. The mangrove forests that edge the mudflats shelter the birds during high tides, night and from harsh weather (storms and sun). Accommodation and plenty of food are the likely magnets for the shorebirds.
Numbers show the Bako-Buntal Bay importance. Around 10,000 to 15,000 shorebirds overwinter in or around the bay. It hosts several globally threatened and near-threatened species including the iconic Chinese egret (Egretta eulophotes). Over 400 individuals of the estimated 2,600 to 3,400 individuals worldwide have been sighted at one time at Bako-Buntal Bay. These birds fish for crabs and fish including mudskippers. They breed in the Yellow Sea between Korea and Japan and the Sea of Japan near Russia with the majority overwintering in the Philippines.
Other threatened species are the lesser adjutant stork (Leptoptilos javanicus) with an estimated flyway population of 6,500 to 8,000 individuals; Chinese crested tern (Sterna bernsteini) with a flyway population of less that 50 mature adults; and Nordmann’s greenshanks (Tringa guttifer) with a flyway population of 500 to 1,000.
The presence of these species can attract birders and other human visitors to appreciate their beauty. But beyond aesthetics and hosting birds are wetlands important?
Yes!
The wetlands are nursery grounds for many species of seafood that we devour at great rates. Your next plate of buttered prawns or steamed fish may have started life in the mangroves of Bako-Buntal Bay. Local delicacies, such as bamboo clams (ambal), are collected by the people along tidal rivers, including the residents of Kampung Bako. These delicacies, while contributing to the income of the collectors, are savoured by all.
I am sure no one wants to have their house flooded, except of course if you live in the wetlands. These areas can hold water and act as a natural means of flood control, while filtering out pollutants, even as a natural sewage treatment system.
In the comfort of our homes and the familiarity of our cities, we can create the perfect environment – not too hot, not too cold – but we continue to depend on Mother Nature. The wandering wetlands are one of her many gifts.