Journal of Threatened Taxa | www.threatenedtaxa.org | 26 October 2019 | 11(13): 14767–14769
An observation of the White-bellied Sea Eagle Haliaeetus leucogaster preying on Saltwater Crocodile hatchlings Crocodylus porosus in Bhitarkanika Wildlife Sanctuary, India
Nimain Charan Palei 1, Bhakta Padarbinda Rath 2 & Bimal Prasanna Acharya 3
1,2 Office of the Principal Chief Conservator of Forests (Wildlife) & Chief Wildlife Warden, Bhubaneswar, Odisha 751007, India.
3 Office of the Divisional Forest Officer, Mangrove Forest Division (Wildlife) Rajnagar, Kendrapara, Odisha 754225, India.
1 firstname.lastname@example.org (corresponding author), 2 email@example.com, 3 firstname.lastname@example.org
The White-bellied Sea Eagle Haliaeetus leucogaster (WBSE) of the family Accipitridae is a monotypic species, closely related to other eagles, kites, hawks, and harriers. It is a resident in India and its world distribution stretches from India and Sri Lanka through southeastern Asia and the Philippines to Australia and Tasmania (del Hoyo et al. 1994). WBSE is native to New Guinea and China and all of the coastal countries of mainland southeastern Asia (Thailand, Malaysia, Singapore, Indonesia, and the Philippines), Australia and India. This species is also found in other island groups, from Bangladesh, Sri Lanka, Burma, Andaman, Laos, Wallacea, Bismarck Archipelago, Nicobars, and Greater Sundas in the west to Hainan, Taiwan, New Ireland, New Britain, and Louisiades in the east, and south around Australia to Tasmania (Strange 2000; Ferguson-Lees et al. 2001). According to IUCN Red List it is categorized as Least Concern (Birdlife International 2016). It is listed in Schedule I of the Indian Wildlife (Protection) Act, 1972 and Appendix II of CITES.
WBSE is occasionally seen in island waters along tidal rivers and in fresh water lakes (Ali & Ripley 1987). Bhitarkanika mangrove ecosystem lies along the eastern coast of India and harbours mangrove forests, rivers, creeks, estuaries, sand bars and mud flats. The resident population of WBSE in Bhitarkanika was estimated 10–15 in 2005 (Gopi & Pandav 2006), and 17–20 in 2007 (Palei et al. 2014). Apart from Bhitarkanika the species has been reported from Chilika Lake and Konark-Balukhanda Wildlife Sanctuary (Rahmani & Nair 2012)
Bhitarkanika Wildlife Sanctuary is located between 86.766–86.050 0E and 20.500–20.800 0N covering an area of 145km2. It occupies unique habitat of mangrove forests, numerous creeks and mud flats located in Kendrapara District of Odisha. The deltaic region is a habitat with mangrove vegetation on either side of the creeks and tidal mudflat. The mangrove ecosystem is one of the largest in the Indian sub-continent and the floral diversity is the second highest in world after Papua New Guinea. Bhitarkanika is home to diverse flora & fauna out of which some are endemic. It is an ideal habitat for reptiles like Estuarine Crocodile, Water Monitor Lizard, King Cobra, and Python. Important avifauna include the kingfishers, storks, ibises, waders, and a variety of migratory ducks like Bar-headed Goose, Brahminy Duck, Gadwall, and Northern Pintail. Estimation of Saltwater Crocodile Crocodylus porosus population is carried out every year during the month of January.
On 13th January 2019 at about 10.00h while surveying for the Saltwater Crocodiles, it was observed that a WBSE was gliding down to capture a crocodile hatchling in the main river of Bhitarkanika (Fig. 1; 20.7330N, 86.8690E). The WBSE mostly hunts and scavenges during dawn and dusk. The WBSE was able to capture the Saltwater Crocodile hatchling with precision and technique (Images 1 & 2). After capture the eagle flew to a nearby perch and started feeding on the soft dorsal portion of the body. After feeding for about 15mins the White-bellied sea Eagle flew away leaving a little portion of the body i.e. the ventral part. The hatchling was less than 2 feet long (Image 1). The WBSE was identified as an adult from its white head, breast, under-wing coverts and tail (Image 1). The upper parts were grey and the black under-wing flight feathers were in contrast with the white coverts; the tail was short and wedge-shaped.
Earlier Gopi & Pandav (2006) reported an incident of predation of a crocodile hatchling by WBSE in Bhitarkanika, but there was no photographic documentation of the incident. Iqbal et al. (2013) reported WBSE attempting to prey upon a Water Monitor Varanus salvator in southern Sumatra, Indonesia. Ali & Ripley (1987) and Dharmakumarsinhji & Lavkumar (1956) reported WBSE take crabs, rats, dead fish and lift domestic duck and piglets in Karwar. del Hoyo et al. (1994) also report rabbits, fruit bats, seagulls (Laridae), cormorants (Phalacrocoracidae) and gannets (Sulidae) in the diet of WBSE. Murthy & Rao (1989) observed WBSE feeding on Dog-faced Water Snake Cerberus rhynchops and a large-sized Wart Snake Achrochordus granulatus in Chilika Lake, Odisha. Rajawat (2019) captured the photographs of an adult Purple Heron Ardea purpurea prey upon a hatchling Mugger Crocodylus palustries in its beaks, along the river bank of Chambal, Palighat area.
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