Long-toed Stint (Calidris subminuta) – A Detailed Study

The Long-toed Stint (Calidris subminuta) is a small shorebird belonging to the family Scolopacidae. It is a migratory wader species, known for its long toes, which help it navigate soft and muddy substrates. This species is often found in wetland habitats, including freshwater marshes, flooded fields, and intertidal zones.

Taxonomy & Classification

• Kingdom: Animalia
• Phylum: Chordata
• Class: Aves
• Order: Charadriiformes
• Family: Scolopacidae
• Genus: Calidris
• Species: Calidris subminuta
• Scientific Name: Calidris subminuta (Middendorff, 1853)

Morphology & Identification

General Appearance

The Long-toed Stint is a small and slender wader with a compact body, measuring 13–16 cm in length, with a wingspan of 34–37 cm. It weighs around 20–30 grams.

Plumage

• Breeding Plumage:
  • Upperparts are brown with dark streaks.
  • The underparts are pale with a buff-colored breast.
  • The head has a distinct pale eyebrow (supercilium).
• Non-Breeding Plumage:
  • The overall plumage is duller, with more grayish-brown upperparts.
  • The underparts remain whitish.

Beak & Legs

• The beak is short, thin, and slightly curved downward, aiding in foraging.
• Legs are yellowish to greenish, distinguishing it from other similar waders.
• The long toes (hence the name) help distribute weight, allowing movement on soft mud.

Call & Vocalization

The species produces a soft “twick” call, often heard in flight or during feeding.

Habitat & Distribution

General Distribution

The Long-toed Stint is a migratory bird that breeds in Siberia and northeastern Asia, particularly in marshy tundra regions. During winter, it migrates to South and Southeast Asia, including India, Bangladesh, Myanmar, Thailand, and Indonesia.

Preferred Habitat

• Freshwater marshes
• Flooded grasslands and rice paddies
• Mudflats and intertidal zones
• Shallow pools with exposed mud

Behavior & Feeding Ecology

Foraging

• The bird actively moves through shallow waters and mudflats in search of food.
• It primarily feeds on insects, larvae, small crustaceans, and aquatic invertebrates.
• The long toes enable it to walk on floating vegetation and soft mud without sinking.

Breeding & Nesting

• The breeding season occurs between May and July in the tundra.
• The nest is a shallow scrape on the ground, lined with leaves and grasses.
• A clutch usually consists of 3–4 eggs, incubated for about 19–21 days.
• Both parents participate in incubation and later in feeding the chicks.

Presence of Long-toed Stint in Sundarban

Occurrence in Sundarban

The Long-toed Stint is not a resident species in the Sundarban but occurs as a winter visitor. During its migration from Siberia and northern Asia, this species is observed in the Sundarban delta, particularly in suitable mudflat and wetland habitats.

Key Areas in Sundarban

• Intertidal mudflats and mangrove edges provide foraging grounds.
• Freshwater tidal creeks and marshes near the mangrove forests offer temporary stopover points during migration.
• It is sometimes seen in wetland areas surrounding the Sundarban, particularly in estuaries and paddy fields where water levels remain suitable.

Challenges in Sundarban

• Habitat degradation due to increasing salinity and shrinking freshwater marshes.
• Climate change and sea level rise affecting intertidal feeding grounds.
• Disturbance from human activities, such as shrimp farming and wetland reclamation.

Conservation Status & Protection in Sundarban

• The Long-toed Stint is currently listed as Least Concern (LC) by the IUCN, but its wetland habitats are under increasing threat.
• Conservation efforts in Sundarban, including wetland protection and regulated tourism, help maintain suitable environments for migratory birds.
• The presence of this species highlights the importance of Sundarban as a key stopover site for various migratory shorebirds.

Conclusion

The Long-toed Stint (Calidris subminuta) is a fascinating migratory shorebird, known for its distinctive long toes and adaptability in wetland habitats. While it primarily breeds in northern Asia, it relies on wintering grounds across South and Southeast Asia, including the Sundarban delta. Ensuring the protection of Sundarban’s wetlands is crucial for the survival of this and many other migratory bird species.