World Migratory Bird Day: Understanding Migration and the Migratory Birds of Bangladesh
Out of 712 bird species of Bangladesh, about 320 species are migratory as the country falls into two major bird migratory flyways – the East-Asian Australasian Flyway and the Central Asian Flyway
Bangladesh's unique geographic location in the Ganges-Brahmaputra-Meghna (GBM) basin with the year-round flow, the monsoon and tropical climate have made it a very important site for migratory birds. When birds travel between their breeding grounds and wintering grounds, they follow specific paths and set routes. These paths – called the Flyways- include suitable habitats where the birds can stop to rest and regain energy to continue their long migration. These flyways are in essence, super-highways in the sky for birds. Bangladesh falls in two such major bird migratory flyways – the East-Asian Australasian Flyway and the Central Asian Flyway.
Despite its small landmass and huge population, Bangladesh has an extraordinary diversity of birdlife due to its location in between those two flyways. Out of 712 bird species of Bangladesh, about 320 species are migratory.
To celebrate this extraordinary natural phenomenon of avian migration, World Migratory Bird Day was first initiated in 2006 by the Secretariat of the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) in collaboration with the Secretariat of the Convention on the Conservation of Migratory Species of Wild Animals (CMS).In 2018, it was decided that the day will be organized twice a year, on the second Saturday in May and in October. Accordingly, this year's World Migratory Bird Day is celebrated on the 8th of May. This day is for raising awareness and to focus on the need for conservation of the migratory birds and their habitats which are threatened around the world.
Each year, especially in winter, thousands of migratory birds arrive in Bangladesh, with the largest concentration in the freshwater wetlands of the north-east of Bangladesh with a population of around one hundred fifty thousand to two hundred thousand and in the southern coastal areas with around 40 to 50 thousand population along with the major rivers of the country. While these migratory birds are mostly waterbirds, other migratory birds find refuge in the forested areas, reeds and grasslands, and in other habitats.
However, in recent times, these numbers are showing a declining trend causing concerns from conservationists.
IUCN has been working tirelessly for the protection of migratory species and their habitat for over a decade. IUCN actively worked in the sustainable management of TangaurHaor, the country's second Ramsar Site, making it one of the most diverse and important wetlands for migratory birds, not only in Bangladesh but for the whole world. Annually, TanguarHaor sees over one hundred thousand migratory waterbirds. Community-based conservation approaches established by IUCN and the abolishment of the leasing system have worked wonders for the conservation of the wetland.
In spite of this, understanding migration patterns and the flyway use of these birds is of utmost importance for their long-term conservation. In 2018, IUCN initiated a research with Linnaeus University of Sweden to attach GPS/GPS satellite tags to 64 long-distant migratory ducks to understand their movement.
Through the satellite tracking study, IUCN is also learning about the international flyways these birds are taking annually. Using this data, a global map is being formulated that will show important sites these birds use during their long migration. With international collaboration, these sites need to be brought under protection as well.
One of the most important findings from that research is the interconnectivity of national wetlands. It was seen that the tagged ducks spend their day-time inside the protected areas of the Haor but at night they move outside the safety of the protected areas to unprotected smaller wetlands and agricultural fields. This exposes them to different threats.
One of the primary threat to these migratory birds is hunting. Not only in Bangladesh, but across their entire flyways, migratory birds are persecuted at an extraordinary level. Although, there are no actual numbers, BirdLife International estimates that there are 25 million birds killed every year, especially during migration.
Another extremely pressing issue for migratory birds is the rapid loss of habitats all over their flyways. Natural wetlands and habitats are being covered to make way for farmlands and new human settlements. The existing rivers and wetlands are over harvested and inadequate food remains for the birds and their chicks.
In Bangladesh, the Bangladesh Forest Department under the Ministry of Environment, Forest and Climate Change (MoEFCC) is putting in significantefforts to protect these species by arresting poachers and illegal hunters, as well as ensuring that the bird habitat are properly preserved and protected.
With the Linnaeus University,another interesting aspect of migration IUCN has looked into is the possible transmission of zoonotic diseases from migratory birds which is now ever more important in context of COVID-19, believed by many a result of zoonotic disease transmission. Zoonotic disease such as bird flu might be carried by migratory ducks and waterbirds from one country to another. Although the results show that possibility of transmission from wild to domestic birds is low, there always a possibility of transmissionas domestic and migratory waterfowl share similar habitats. Therefore, extreme precaution is always necessary to avoid zoonotic diseases.
Migratory waterbirds are also vital for wetland productivity and fish production. Feces from migratory waterbirds fertilizes the aquatic vegetation of wetlands, which in turn ensures food and habitat for fish. Migratory birds also help control pests and are effective pollinators.
For the conservation of migratory birds, in Bangladesh, it is imperative that their habitats are protected and protected areas are well managed. While major wetlands in Bangladesh are protected, it is important that the rest are brought under protection and proper management. Large tracts of riverine habitat that are also highly significant for migratory birds need adequate protection.
Site specific management plans are needed for each habitat to ensure conservation actions are focused and thoroughly implemented. One of major threats observed recently is the influx of cattle in the protected wetlands, causing threat to natural reeds and grasslands vital for smaller migratory passerine birds. IUCN has also recorded exponential increase in domestic duck farms inside the haor ecosystems, which threatens to disrupt the delicate balance of the wetland ecosystems.Conversion and leasing of large beels and important water-bodies for fishing in protected areas like Hakaluki and Hail Haors also pose existential threats to wintering migratory birds there. Besides, threats to other ecosystems like forests, reed and grasslands need to be understood and managed to protect the habitat of migratory birds.
To increase protection and habitat of these species, we need to incorporate the concept of community conservation areas to assist the already formed protected areas. A novel approach would be the Other Effective Area-based Conservation Measures (OECMs), as highlighted in the Aichi Biodiversity Target 11 of the Convention on Biological Diversity (CBD). OECMs can be a tool to engage the local communities in conservation as well.
Aichi Targets aim to conserve at least 17 percent of terrestrial and inland water areas and 10 percent of coastal and marine areas of particular importance for biodiversity and ecosystem service through effectively and equitably managed, ecologically representative and well-connected systems of protected areas and other effective area-based conservation measures (OECMs). Community engagement can ensure this system is connected to protected areas, as it is already established that migratory birds move from protected to unprotected areas.This will also contribute in achieving Sustainable Development Goal (SDG) targets 14 and 15.
On this year's World Migratory Bird Day, Bangladesh can be proud of its efforts so far to protect the migratory avifauna of the country while acknowledging that a lot of works are ahead of us considering multifaceted challenges. Although Bangladesh's diverse ecosystems have been hosting the migratory birds over centuries, innovative approaches like OECM and citizen science need to be incorporated to the conservation rhetoric. IUCN continuesits work effortlessly to ensure that these innovative approaches are promoted from grassroots to policy level to uphold the theme of this year's World Migratory Bird Day at all aspects of our life: "Sing, Fly, Soar – like a bird."