This checklist includes birds that are consistent with the Sundarbans mangrove–estuary–mudflat ecosystem and widely accepted regional checklists.
The Sundarbans mangrove complex is globally recognized for its exceptional ecological character—an immense tidal delta where saline and freshwater processes meet daily, shaping creeks, mudflats, reedbeds, and forested islands. In such a landscape, bird diversity can appear deceptively unlimited; however, scientific credibility depends on distinguishing verified Sundarbans birds from species that belong to entirely different biogeographic zones (such as Himalayan forests, arid plains, or non-Asian regions).
This article presents a carefully filtered and habitat-consistent picture of the verified birds of the Sundarbans, emphasizing species that are repeatedly recorded within the mangrove–estuary–mudflat system and its immediately connected wetlands and buffer edges.
Understanding “Verified” Records in the Sundarbans
In the Sundarbans, the word verified has a precise ecological meaning. A species is treated as verified when its occurrence is supported by consistent field observations and its ecology matches the habitats actually available within the mangrove–estuarine environment. This prevents the common error of importing birds from distant habitats (high-altitude hills, dense montane forests, dry scrublands, or other continents) into a Sundarbans checklist.
Core mangrove verification: repeated sightings within tidal creeks, forest canals, island edges, and mangrove canopy zones.
Estuary and mudflat verification: regular seasonal presence on exposed intertidal flats and sandbars, especially during winter migration.
Buffer wetland verification: dependable records from adjoining ponds, embankments, reedbeds, and village-fringe wetlands that function ecologically as part of the delta system.
The Habitat Mosaic That Creates Sundarbans Bird Diversity
1) Mangrove Creeks and Tidal Forest Edges
The tidal creeks and forest edges are the signature habitats of the Sundarbans. Here, birds must tolerate saline water, fluctuating tides, and dense mangrove structure. Species that specialize in fishing from perches, stalking shallow water, or navigating creeks tend to dominate this zone.
2) Estuaries, Sandbars, and Intertidal Mudflats
During low tide, large areas of mud and sand are exposed, providing a short-lived but extremely productive feeding ground. This is the core arena for migratory shorebirds and also supports gulls, terns, and specialized riverine species. The daily tidal rhythm creates a constant cycle of foraging and roosting movements.
3) Marshes, Reedbeds, and Freshwater-Influenced Wetlands
Within and around the delta, reedbeds, marsh margins, and freshwater pockets host a different set of birds—rails, crakes, jacanas, and some waterfowl. These habitats are especially important where freshwater influence is stronger and aquatic vegetation is present.
4) Human-Modified Buffer Zones
The Sundarbans landscape includes embankments, village groves, paddy fields, and pond systems. These areas add many adaptable passerines and open-country birds. Properly handled, buffer-zone records can be scientifically valid—provided the species is ecologically consistent with deltaic lowlands.
Order Anseriformes (Ducks, Geese & Whistling-Ducks)
Verified Waterfowl of the Sundarbans
Winter transforms the delta’s calmer water bodies into a seasonal refuge for migratory ducks and allied waterfowl. Their presence depends on water depth, salinity gradients, and the availability of submerged food resources. In favorable years, sheltered wetlands and wide creeks host impressive congregations.
The Sundarbans mudflats are among the most productive feeding habitats in eastern India’s coastal zone. Shorebirds probe for worms, crustaceans, and mollusks within soft sediments, while gulls and terns track fish movement across tidal fronts. This assemblage is strongly seasonal, peaking during winter when migratory traffic is highest.
The Sundarbans are especially celebrated for kingfishers. Tidal creeks provide constant fishing opportunities, while mangrove perches offer stable hunting platforms. Along open edges and village fringes, insect-rich clearings support bee-eaters and aerial insectivores.
Order Coraciiformes (Kingfishers, Bee-eaters & Rollers)
Common Kingfisher (Alcedo atthis)
Blue-eared Kingfisher (Alcedo meninting)
Pied Kingfisher (Ceryle rudis)
White-throated Kingfisher (Halcyon smyrnensis)
Stork-billed Kingfisher (Pelargopsis capensis)
Collared Kingfisher (Todiramphus chloris)
Blue-tailed Bee-eater (Merops philippinus)
Chestnut-headed Bee-eater (Merops leschenaulti)
Indian Roller (Coracias benghalensis)
Dollarbird (Eurystomus orientalis)
Owls and Nocturnal Residents
Nocturnal birds are an essential yet under-documented component of the Sundarbans. Their verified presence is typically established through night-time calls, spotlight surveys, and repeated records around forest edges and quieter human settlements.
Order Strigiformes (Owls)
Spotted Owlet (Athene brama)
Collared Scops Owl (Otus bakkamoena)
Oriental Scops Owl (Otus sunia)
Brown Fish Owl (Ketupa zeylonensis)
Indian Eagle-Owl (Bubo bengalensis)
Order Bucerotiformes (Hoopoe)
Eurasian Hoopoe (Upupa epops)
Parakeets and Village-Edge Forest Birds
Parakeets contribute strongly to the soundscape of the Sundarbans fringe. They are most often detected in village groves, mixed vegetation near embankments, and transitional woodland patches where fruiting trees and nesting cavities are available.
Order Psittaciformes (Parakeets)
Rose-ringed Parakeet (Psittacula krameri)
Plum-headed Parakeet (Psittacula cyanocephala)
Alexandrine Parakeet (Psittacula eupatria)
Red-breasted Parakeet (Psittacula alexandri)
Herons, Egrets, Storks, and the Tidal Fish Web
The Sundarbans are sustained by a powerful estuarine food web where tidal pulses concentrate fish, prawns, and small aquatic animals along creek margins. Wading birds exploit this abundance through diverse feeding strategies—stalking, spearing, and rapid lunging. Their distribution often mirrors water clarity, prey availability, and safe roosting sites.
Order Pelecaniformes (Herons, Egrets, Ibises & Storks)
Little Egret (Egretta garzetta)
Great Egret (Ardea alba)
Intermediate Egret (Ardea intermedia)
Cattle Egret (Bubulcus ibis)
Grey Heron (Ardea cinerea)
Purple Heron (Ardea purpurea)
Indian Pond Heron (Ardeola grayii)
Black-crowned Night Heron (Nycticorax nycticorax)
Striated Heron (Butorides striata)
Glossy Ibis (Plegadis falcinellus)
Eurasian Spoonbill (Platalea leucorodia)
Painted Stork (Mycteria leucocephala)
Asian Openbill (Anastomus oscitans)
Black Stork (Ciconia nigra)
Woolly-necked Stork (Ciconia episcopus)
Lesser Adjutant (Leptoptilos javanicus)
Cormorants and Darter: Specialists of Fish-Rich Creeks
Where fish movements are predictable, pursuit-divers become highly visible. Cormorants and darters frequently patrol tidal channels and then roost on exposed branches to dry their wings, an adaptation that improves feather function after repeated dives.
Order Suliformes (Cormorants & Darter)
Great Cormorant (Phalacrocorax carbo)
Indian Cormorant (Phalacrocorax fuscicollis)
Little Cormorant (Microcarbo niger)
Oriental Darter (Anhinga melanogaster)
Raptors of the Sundarbans: Predators Above the Tides
The Sundarbans support a layered predator guild. Some raptors specialize in fishing, others exploit reptiles and small mammals along embankments, and some follow human activity for scavenging opportunities. Because the delta offers long sightlines over water and mudflats, aerial hunting is often effective.
Order Accipitriformes (Raptors)
Black Kite (Milvus migrans)
Brahminy Kite (Haliastur indus)
White-bellied Sea Eagle (Haliaeetus leucogaster)
Pallas’s Fish Eagle (Haliaeetus leucoryphus)
Osprey (Pandion haliaetus)
Crested Serpent Eagle (Spilornis cheela)
Shikra (Accipiter badius)
Chinese Sparrowhawk (Accipiter soloensis)
Grey-faced Buzzard (Butastur indicus)
Selected Verified Passerines of the Sundarbans Landscape
Passerines are often less dramatic than large waterbirds, yet they perform essential roles—controlling insects, dispersing seeds, and sustaining the broader food web. Many are most frequent in buffer areas but remain ecologically tied to the delta’s lowland structure.
Passeriformes (Selected Common & Verified Delta Birds)
The verified birds of the Sundarbans represent an ecologically disciplined portrait of the delta’s avian life. Rather than relying on inflated lists, a verified approach emphasizes habitat realism: tidal creeks and mangrove edges for kingfishers and waders, mudflats for migratory shorebirds, and buffer wetlands for rails, passerines, and seasonal waterfowl.
This is the foundation of accurate wildlife interpretation, responsible birdwatching, and credible conservation storytelling for one of the planet’s most important mangrove ecosystems.
Editorial Note
The Sundarbans bird community changes seasonally. Winter brings large numbers of shorebirds and waterfowl,
while mangrove residents remain year-round.