Ruddy Turnstone (Arenaria interpres) – A Detailed Study

Taxonomy

• Kingdom: Animalia
• Phylum: Chordata
• Class: Aves
• Order: Charadriiformes
• Family: Scolopacidae
• Genus: Arenaria
• Species: Arenaria interpres

Morphology & Physical Characteristics

The Ruddy Turnstone is a medium-sized shorebird known for its distinctive plumage and behavior.

• Size: Approximately 22–24 cm in length
• Wingspan: 50–57 cm
• Weight: 85–150 grams
• Coloration:
  • Breeding plumage: Brightly patterned with black, white, and chestnut-brown markings.
  • Non-breeding plumage: More subdued brown and white tones.
• Beak: Short, stout, and slightly upturned, used effectively for flipping over stones and debris to find food.
• Legs & Feet: Bright orange legs, providing contrast against its mottled body.
• Distinctive Features:
  • Bold facial markings in breeding plumage.
  • Black-and-white pattern on the head and chest.
  • Short, pointed tail with white edges.

Habitat & Distribution

The Ruddy Turnstone is a highly migratory shorebird found across coastal areas worldwide.

• Breeding Grounds:
  • Arctic regions of North America, Europe, and Asia.
• Wintering Grounds:
  • Coastal areas of Africa, South America, Australia, and South & Southeast Asia.
• Preferred Habitat:
  • Coastal mudflats, sandy beaches, estuaries, and rocky shorelines.
  • Occasionally seen in inland wetlands and riverbanks.

Behavior & Feeding Habits

• Foraging Technique:
  • The Ruddy Turnstone gets its name from its unique way of searching for food—flipping over stones, shells, and seaweed to uncover hidden invertebrates.
• Diet:
  • Small crustaceans, insects, mollusks, and carrion.
  • Occasionally scavenges fish scraps or bird eggs.
• Social Behavior:
  • Often seen in small flocks, particularly in wintering grounds.
  • Sometimes mixes with other shorebirds.

Special Features & Adaptations

• Strong Beak: Uniquely adapted for turning over stones and debris in search of food.
• Long-Distance Migration: Capable of covering thousands of kilometers between breeding and wintering grounds.
• Camouflaging Plumage: Blends well with rocky shorelines, offering protection from predators.

Presence of Ruddy Turnstone in Sundarban

Occurrence in the Sundarban Biosphere Reserve

The Sundarban is a dynamic, biodiverse region consisting of mangrove forests, mudflats, estuaries, and tidal waterways, making it an essential habitat for migratory birds like the Ruddy Turnstone.

• Migration Pattern in Sundarban:
  • The Ruddy Turnstone visits Sundarban during winter months (October to April) as part of its migratory route along the East Asian-Australasian Flyway.
• Habitats within Sundarban:
  • Intertidal mudflats and sandbanks near estuaries.
  • Along the coastal fringes and mangrove-lined shores where they forage for food.
• Frequency of Sightings:
  • Although not abundant, it is a regular winter visitor seen in certain pockets of the Sundarban delta.
  • Often found in Sajnekhali Bird Sanctuary, Dobanki, and other open mudflats in the region.

Importance of Sundarban for Ruddy Turnstone

• Vital Stopover Site: Provides resting and refueling grounds for the bird during migration.
• Rich Food Availability: The nutrient-rich waters of Sundarban ensure a steady supply of invertebrates.
• Protection & Conservation: The Sundarban, being a UNESCO World Heritage Site, offers a relatively safe haven for migratory birds despite environmental threats.

Threats & Conservation Status

• IUCN Red List Status: Least Concern (LC)
• Threats in Sundarban:
  • Climate Change & Rising Sea Levels – Threatens the intertidal habitats.
  • Habitat Disturbance – Due to increased human activities like fishing and tourism.
  • Pollution – Oil spills, plastic waste, and chemical runoff affecting food sources.

Conservation Efforts

• Protected Areas & Bird Sanctuaries in Sundarban help maintain crucial habitats.
• Awareness & Sustainable Tourism Initiatives support conservation.
• Global Conservation Agreements like the East Asian-Australasian Flyway Partnership (EAAFP) help in monitoring migratory shorebirds.

Conclusion

The Ruddy Turnstone (Arenaria interpres) is a fascinating shorebird that showcases remarkable adaptability and endurance in its migratory journey. While its presence in Sundarban is seasonal, this region serves as an important wintering ground for the species. Preserving the delicate ecosystem of Sundarban’s mudflats and coastal wetlands is essential for maintaining the migratory patterns of shorebirds like the Ruddy Turnstone, ensuring their survival for generations to come.