Kaziranga Raptor and Stork Survey

The Kaziranga Tiger Reserve (KTR) authority, in collaboration with researchers from Gauhati University, released the findings of a rapid avian survey focusing on two critical ecological groups: Raptors (birds of prey) and Storks.

Key Objective: To document species richness and population distribution across KTR’s administrative zones.
Release Date Significance: June 5 (World Environment Day).

Geographical and Ecological Significance

Assam’s rich, diverse wetlands and the Himalayan foothills act as vital ecosystems for avian biodiversity.

Raptor Diversity: India hosts 112 species of raptors (both diurnal/day-active and nocturnal/night-active). Kaziranga and its adjoining landscape harbor nearly 50 species (~45% of India’s raptor diversity).
Stork Diversity: Globally, tropical and subtropical regions host 20 stork species. India is home to 8 of these species. Remarkably, all 8 species are found in Assam, with 6 documented specifically within Kaziranga during this survey.

Zonal Distribution inside Kaziranga

The survey covered three major administrative divisions of the park, showing high spatial variation:

Administrative Division	Raptors Recorded	Storks Recorded
Eastern Assam Wildlife Division	21 species	5 species
Biswanath Wildlife Division	20 species	6 species
Nagaon Wildlife Division	14 species	5 species

Species-Specific Highlights

A. Storks

Most Abundant: Asian Openbill (Anastomus oscitans) — 92 individuals.
Rarest Spotted: Greater Adjutant Stork (Leptoptilos dubius) — only 3 individuals recorded. (Note: Crucial indicator of wetland degradation).

B. Raptors

Most Abundant: Himalayan Griffon Vulture (Gyps himalayensis) — 69 individuals.
Rarest Spotted: Booted Eagle and White-tailed Eagle (only 1 individual each).

C. Enigmatic Species: Pallas’s Fish Eagle (Haliaeetus leucoryphus)

Kaziranga serves as a critical global stronghold for this species.
According to a Wildlife Institute of India (WII) study, KTR holds 10 active nests, making it the protected area with the highest density of breeding sites for Pallas’s Fish Eagle in the world.

Preliminary Examination Relevant Question

Q1. Consider the following statements regarding the avian diversity of Northeast India:

India is home to nearly half of the world’s tropical and subtropical stork species, all of which can be found in the state of Assam.
The Kaziranga National Park holds the highest number of breeding sites in the world for the Pallas’s Fish Eagle.
The Himalayan Griffon Vulture is a nocturnal raptor commonly sighted across the wetlands of the Brahmaputra valley.

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 2 only

(d) 1, 2, and 3

Correct Answer: (a) 1 and 2 only

Explanation: Statement 1 is correct (India has 8 out of 20 global stork species, and all 8 are found in Assam). Statement 2 is correct based on the WII survey. Statement 3 is incorrect because Vultures are diurnal (day-active) raptors, not nocturnal.

Mains Examination Relevant Question

Q. “The conservation of apex avian predators like raptors and indicator species like storks reflects the holistic health of a wetland-floodplain ecosystem.” In light of recent avian surveys in protected areas of Northeast India, discuss the ecological significance of these birds and the challenges threatening their critical habitats. (150 words, 10 Marks)

Model Answer Structure/Hints:

Introduction: Mention the recent Kaziranga avian survey highlighting that KTR holds ~45% of India’s raptor diversity and serves as the world’s largest breeding site for the Pallas’s fish eagle.
Ecological Significance:
- Raptors as Apex Predators: Regulate populations of small mammals, fish, and reptiles; act as health indicators of the food chain. Vultures act as nature’s scavengers preventing disease outbreaks.
- Storks as Indicator Species: Their presence relies directly on healthy, undisturbed wetlands and abundant fish populations (e.g., Asian Openbill, Greater Adjutant).
Threats to Habitats: Encroachment of wetlands, agricultural runoff leading to pesticide bioaccumulation in birds of prey, infrastructure development, and climate-induced flood alterations in the Brahmaputra basin.
Conclusion: Emphasize the need for community-led wetland conservation, regional zoning plans, and collaborative academic-forest department monitoring setups.