Foraging postures and techniques used by the White-bellied Heron Ardea insignis Hume, 1878 (Aves: Pelecaniformes: Ardeidae) in Namdapha Tiger Reserve, India
DOI:
https://doi.org/10.11609/jott.10508.18.7.29251-29260Keywords:
Arunachal Pradesh, body postures, foraging technique, freshwater rivers, northeastern India, prey handlingAbstract
The White-bellied Heron Ardea insignis occurs in Bhutan, India, and Myanmar. Bhutan supports the majority of the known global population (approximately 30 individuals), followed by India (around 10 individuals), while only a few individuals occur in Myanmar. The population continues to decline across its range, posing a serious threat to the species’ survival. This heron is unique in preferring fast-flowing freshwater rivers, yet its foraging behaviour remains poorly understood. As a fish-eating bird, a continuous supply of freshwater fish is essential for its survival and reproduction. From 2013 to 2017, its foraging behaviour was studied in Namdapha Tiger Reserve, the only site in India where most individuals are found. The aim was to understand how this visual predator forages in fast-flowing rivers, where strong currents make prey detection and capture difficult. It was found that the heron employs a variety of postures and techniques to cope with these conditions. Using continuous focal sampling, individuals were observed and documented their body postures and prey capture methods through photography. Over approximately 850 h of observation, the herons were seen feeding exclusively on fish. Their foraging behaviour was strongly influenced by water current, requiring specific techniques to maximise prey capture. The birds displayed distinctive movement patterns and postures to avoid detection by prey and to handle captured fish effectively. Some postures were associated with unsuccessful capture attempts. This study highlights previously undocumented feeding behaviours, which are important for developing conservation strategies aimed at protecting the species and its specialised habitat.
References
Aarif, K.M., A. Nefla, K.A. Rubeena, Y. Xu, Z. Bouragaoui, M. Nasser, C.T. Shifa, T.R. Athira, K. Jishnu, J. Anand, S. Manokaran, P.P. Moosa, A. Gopinath, O.R. Reshi, K.M. Rajaneesh, H. Byju, T.V. Joydas, K.P. Manikandan, M.I. Naikoo, C. Sonne & S.B. Muzaffar (2025). Assessing environmental change and population declines of large wading birds in southwestern India. Environmental and Sustainability Indicators 25: 100572. https://doi.org/10.1016/j.indic.2024.100572
Altman, J. (1974). Observational study of behaviour: sampling methods. Behaviour 49: 227–267.
Kelly, J.F., D.E. Gawlik & D.K. Kieckbusch (2003). An updated account of wading bird foraging behavior. The Wilson Bulletin 115(1): 105–07. http://www.jstor.org/stable/4164528
Kushlan, J.A. & J.A. Hancock (2005). The Herons. Oxford University Press, Oxford, 454 pp.
Kushlan, J.A. (1976). Feeding behavior of North American Heron. Auk 93: 86–94.
Kushlan, J.A. (1978). Feeding ecology of wading birds. Research Report of the National Audubon Society: Report No 7. National Audubon Society, New York, U.S.A.
Kushlan, J.A. (2011). The terminology of courtship, nesting, feeding and maintenance in herons. HeronConservation, The IUCN-SSC Heron Specialist Group, 1–11 pp. Accessed on 22.vi.2016. https://heronconservation.org/media/resources/Heron-Behavior-Terminology.pdf
Maheswaran, G. & A.R. Rahmani (2001). Effects of water level changes and wading bird abundance on the foraging behaviour of Black-necked Stork Ephippiorhynchus asiaticus in Dudwa National Park, India. Journal of Biosciences 26(3): 373–382. https://doi.org/10.1007/BF02703747
Maheswaran, G. & A.R. Rahmani (2002). Foraging behaviour and feeding success of the Black-necked Stork Ephippiorhynchus asiaticus in Dudwa National Park, Uttar Pradesh, India. Journal of Zoology (London) 258: 189–195. https://doi.org/10.1017/S0952836902001309
Maheswaran, G. & A.R. Rahmani (2008). Foraging technique and prey-handing time in Black-necked Stork Ephippiorhynchus asiaticus. Integrative Zoology 3(4): 274–279. https://doi.org/10.1111/j.1749-4877.2008.00101.x
Maheswaran, G., I.P. Acharja, L.K. Sharma, H.S. Mondal, T. Mukherjee, I. Alam & A. Majumder (2021a). Save the White-bellied Heron from extinction. Science 373(6561): 1317. https://doi.org/10.1126/science.abl9682
Maheswaran, G., L.K. Sharma, H.S. Mondal & T. Mukherjee (2021b). White-bellied Heron, a species on the verge of extinction: ensemble model reveals loss of habitats and resultant prolonged isolation driving the species to extinction. Ecological Informatics 64: 101383 https://doi.org/10.1016/j.ecoinf.2021.101383
Maheswaran, G. & S. Das (2025). New threat to the Critically Endangered White-bellied Heron in Namdapha Tiger Reserve, India. Oryx 59(2): 150–151. https://doi.org/10.1017/S0030605325000134
Martin, P. & P. Bateson (2007). Measuring Behaviour: An Introductory Guide, 3rd Edition. Cambridge University Press, 186 pp.
Meyerriecks, A.J. (1960). Comparative Breeding Behavior of Four Dpecies of North American Herons. Publications of the Nuttall Ornithological Club, No. 2, 158 pp.
Mondal, H.S. & G. Maheswaran (2014). First nesting record of White-bellied Heron Ardea insignis in Namdapha Tiger Reserve, Arunachal Pradesh, India. Birding ASIA 21: 13–17.
Mondal, H.S. & G. Maheswaran (2021). Foraging Ecology of White-bellied Heron (Ardea insignis) in the Fast-flowing Rivers of Namdapha Tiger Reserve, Arunachal Pradesh, India. Waterbirds 44(4): 389–396. https://doi.org/10.1675/063.044.0401
Mondal, H.S. & G. Maheswaran (2025). Assessment of nest and nesting activities of White-bellied Heron Ardea insignis Hume, 1878 (Aves: Ardeidae) in the broad-leaved forests of northeastern India. Journal of Threatened Taxa 17(3): 26690–26696. https://doi.org/10.11609/jott.9476.17.3.26690-26696
Reddy, S.K., G. Maheswaran, G.V. Gopi, A. Majumder, I. Alam, H.S. Mondal, B.B. Bhat, D. Yongam, T. Yamcha, S. Patgiri & U.K. Sahoo (2021). Nesting of the White-bellied Heron Ardea insignis in Anjaw District, Arunachal Pradesh, India. Indian BIRDS 17(4): 115–118.
Rodgers, J.A. (1983). Foraging behavior of seven species of herons in Tampa Bay, Florida. Colonial Waterbirds 6: 11–23.
Stephens, D.W. & J.H. Krebs (1986). Foraging Theory. Princeton, New Jersey, Princeton University Press, 247 pp.
Published
Issue
Section
License
Copyright (c) 2026 Himadri Sekhar Mondal, Gopinathan Maheswaran
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors own the copyright to the articles published in JoTT. This is indicated explicitly in each publication. The authors grant permission to the publisher Wildlife Information Liaison Development (WILD) Society to publish the article in the Journal of Threatened Taxa. The authors recognize WILD as the original publisher, and to sell hard copies of the Journal and article to any buyer. JoTT is registered under the Creative Commons Attribution 4.0 International License (CC BY), which allows authors to retain copyright ownership. Under this license the authors allow anyone to download, cite, use the data, modify, reprint, copy and distribute provided the authors and source of publication are credited through appropriate citations (e.g., Son et al. (2016). Bats (Mammalia: Chiroptera) of the southeastern Truong Son Mountains, Quang Ngai Province, Vietnam. Journal of Threatened Taxa 8(7): 8953–8969. https://doi.org/10.11609/jott.2785.8.7.8953-8969). Users of the data do not require specific permission from the authors or the publisher.
