Hostname: page-component-54dcc4c588-smtgx Total loading time: 0 Render date: 2025-10-04T06:09:01.418Z Has data issue: false hasContentIssue false
  • English
  • Français

Wild or farmed? Natural water-bodies, not aquaculture, drive fish intake in a top predator along the Odisha coast, India

Published online by Cambridge University Press:  31 July 2025

Sakti Prasad Pattnayak Open the ORCID record for Sakti Prasad Pattnayak [Opens in a new window] ,
Sandeep Rout ,
Biswajit Samantaray  and
B. Anjan Kumar Prusty Open the ORCID record for B. Anjan Kumar Prusty [Opens in a new window]
Sakti Prasad Pattnayak
Affiliation:
Department of Environmental Science, https://ror.org/03m3xkg41 Berhampur University , Berhampur - 760007, Odisha, India
Sandeep Rout
Affiliation:
Department of Environmental Science, https://ror.org/03m3xkg41 Berhampur University , Berhampur - 760007, Odisha, India
Biswajit Samantaray
Affiliation:
Department of Environmental Science, https://ror.org/03m3xkg41 Berhampur University , Berhampur - 760007, Odisha, India
B. Anjan Kumar Prusty*
Affiliation:
Department of Environmental Science, https://ror.org/03m3xkg41 Berhampur University , Berhampur - 760007, Odisha, India
*
Corresponding author: B. Anjan Kumar Prusty; Email: anjaneia@gmail.com
Get access Rights & Permissions [Opens in a new window]

Summary

Coastal wetlands, known for their remarkable productivity and diverse ecological functions, face growing threats from aquaculture expansion, which can fragment natural habitats and disrupt water flow. In this study, we focused on White-bellied Sea-Eagles Haliaeetus leucogaster along the eastern coast of Odisha, India, to see how these top predators adapt to accelerating aquaculture. Across 22 nesting sites over three breeding seasons (2021–2024), we analysed 3,319 prey items, and found that fish dominated at 66.89%, followed by birds (25.64%), reptiles (3.31%), invertebrates (3.16%), and mammals (0.99%). Using generalised additive models (GAMs), we evaluated various landscape factors influencing the proportion of fish in WBSE diets. Our results revealed that shorter distances to natural water-bodies and higher water coverage strongly influenced higher fish intake, while aquaculture-related variables did not increase fish consumption. These patterns indicate that WBSEs favour wild fish in less-disturbed wetlands, likely because of better energy returns, lower risks, and convenient perching spots. Consequently, our findings highlight the need to safeguard natural aquatic habitats for sustaining apex predators and point to ways of reconciling aquaculture growth with wetland conservation. By clarifying how the eagles respond to changes in coastal landscapes, we offer key insights for preserving biodiversity under fast-paced environmental transformation.

Keywords

Apex predatorsAquacultureCoastal wetlandsDietLandscape modificationWhite-bellied Sea-Eagle

Information

Type
Research Article
Information
Bird Conservation International , Volume 35 , 2025 , e25
Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of BirdLife International

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

Akinwande, M.O., Dikko, H.G. and Samson, A. (2015). Variance Inflation Factor: As a condition for the inclusion of suppressor variable(s) in regression analysis. Open Journal of Statistics 5, 754–767. https://doi.org/10.4236/ojs.2015.57075CrossRefGoogle Scholar
Azman, N.M., Zainudin, M.S.M.M., Sah, S.A.M. and Latip, N.S.A. (2013). The distribution of nesting White-bellied Sea-eagle (Haliaeetus leucogaster) in Penang National Park, Malaysia: Conservation and management issues. Tropical Life Sciences Research 24, 51–64.Google ScholarPubMed
Barbier, E.B., Hacker, S.D., Kennedy, C., Koch, E.W., Stier, A.C. and Silliman, B.R. (2011). The value of estuarine and coastal ecosystem services. Ecological Monographs 81, 169–193. https://doi.org/10.1890/10-1510.1CrossRefGoogle Scholar
Butet, A., Rantier, Y. and Bergerot, B. (2022). Land use changes and raptor population trends: A twelve-year monitoring of two common species in agricultural landscapes of Western France. Global Ecology and Conservation 34, e02027. https://doi.org/10.1016/j.gecco.2022.e02027CrossRefGoogle Scholar
Byju, H., Raveendran, N. and Mathiyazhagan, A.J. (2023). Powerline pylons: an unusual nesting success of White-bellied Sea-Eagle Haliaeetus leucogaster (Gmelin, 1788) (Aves: Accipitriformes: Accipitridae) from Ramanathapuram, southeastern coast of India. Journal of Threatened Taxa 15, 23610–23614. https://doi.org/10.11609/jott.8460.15.7.23610-23614Google Scholar
Caro, T. (2010). Conservation by Proxy: Indicator, Umbrella, Keystone, Flagship, and Other Surrogate Species. Washington DC: Island Press.Google Scholar
Corbett, L. and Hertog, T. (2011). Diet and breeding of White-bellied Sea-Eagles Haliaeetus leucogaster in subtropical river habitats in the Northern Territory, Australia. Corella 35, 41–48.Google Scholar
Cruz, C., Santulli-Sanzo, G. and Ceballos, G. (2021). Global patterns of raptor distribution and protected areas optimal selection to reduce the extinction crises. Proceedings of the National Academy of Sciences – PNAS 118, e2018203118. https://doi.org/10.1073/pnas.2018203118CrossRefGoogle ScholarPubMed
Debus, S.J.S. (2008). Biology and diet of the White-bellied Sea-Eagle Haliaeetus leucogaster breeding in northern inland New South Wales. Australian Field Ornithology 25, 165–193.Google Scholar
Demerdzhiev, D., Dobrev, D., Popgeorgiev, G. and Stoychev, S. (2022). Landscape alteration affects the demography of an endangered avian predator by reducing the habitat quality. Avian Research 13, 100030. https://doi.org/10.1016/j.avrs.2022.100030CrossRefGoogle Scholar
Dempster, T., Arechavala‐Lopez, P., Barrett, L.T., Fleming, I.A., Sanchez‐Jerez, P. and Uglem, I. (2018). Recapturing escaped fish from marine aquaculture is largely unsuccessful: alternatives to reduce the number of escapees in the wild. Reviews in Aquaculture 10, 153–167. https://doi.org/10.1111/raq.12153CrossRefGoogle Scholar
Dwarakish, G.S. and Ganasri, B.P. (2015). Impact of land use change on hydrological systems: A review of current modeling approaches. Cogent Geoscience 1, 1115691. https://doi.org/10.1080/23312041.2015.1115691CrossRefGoogle Scholar
Ekblad, C., Tikkanen, H., Sulkava, S. and Laaksonen, T. (2020). Diet and breeding habitat preferences of White-tailed Eagles in a northern inland environment. Polar Biology 43, 2071–2084. https://doi.org/10.1007/s00300-020-02769-1CrossRefGoogle Scholar
Ghaffari, H. and Devos, P. (2024). On the role of audio frontends in bird species recognition. Ecological Informatics 81, 102573. https://doi.org/10.1016/j.ecoinf.2024.102573CrossRefGoogle Scholar
Gunawan, G., Purwanto, A. and Khaleghizadeh, A. (2015). The White-Bellied Sea Eagle at Kepulauan Seribu National Park, Java, Indonesia. Пернатые Хищники и Их Охрана – Raptors Conservation 30, 104–112.Google Scholar
Halpern, B.S., Walbridge, S., Selkoe, K.A., Kappel, C.V., Micheli, F., D’Agrosa, C. et al. (2008). A global map of human impact on marine ecosystems. Science 319, 948–952. https://doi.org/10.1126/science.1149345CrossRefGoogle ScholarPubMed
Heilpern, S.A., Almeida, R.M., Fiorella, K.J., Flecker, A.S., Williams, D. and McIntyre, P.B. (2023). Nutritional challenges of substituting farmed animals for wild fish in human diets. Environmental Research Letters 18, 114030. https://doi.org/10.1088/1748-9326/ad02abCrossRefGoogle Scholar
Jia, K., Huang, A., Deng, L., Yin, X., Deng, Y., Hou, Z. et al. (2024). Persistent yet limited impact of protected areas on coastal wetland restoration in megacity cores. Global Ecology and Conservation 56, e03270. https://doi.org/10.1016/j.gecco.2024.e03270CrossRefGoogle Scholar
Li, Y. (2018). Study of the interactive effect of prey toxin and optimal foraging strategy on a predator–prey model. International Journal of Biomathematics 11, 1850050. https://doi.org/10.1142/S179352451850050XCrossRefGoogle Scholar
Lieber, L., Nimmo-Smith, W.A.M., Waggitt, J.J. and Kregting, L. (2019). Localised anthropogenic wake generates a predictable foraging hotspot for top predators. Communications Biology 2, 123. https://doi.org/10.1038/s42003-019-0364-zCrossRefGoogle ScholarPubMed
Mak, B., Drewitt, E.J.A., Francis, R.A. and Chadwick, M.A. (2023). The raptor lockdown menu—Shifts in prey composition suggest urban peregrine diets are linked to human activities. People and Nature 5, 795–807. https://doi.org/10.1002/pan3.10445CrossRefGoogle Scholar
Martinez, A.S., Willoughby, J.R. and Christie, M.R. (2018). Genetic diversity in fishes is influenced by habitat type and life-history variation. Ecology and Evolution 8, 12022–12031. https://doi.org/10.1002/ece3.4661CrossRefGoogle ScholarPubMed
Mohanty, R., Mohapatra, A., Mohanty, S., Mishra, S., Khan, M. and Pattnaik, A. (2015). Ichthyofaunal diversity of Chilika Lake, Odisha, India: an inventory, assessment of biodiversity status and comprehensive systematic checklist (1916-2014). Check List 11, 1–19. https://doi.org/10.15560/11.6.1817CrossRefGoogle Scholar
Nadjafzadeh, M., Hofer, H. and Krone, O. (2016). Sit-and-wait for large prey: foraging strategy and prey choice of White-tailed Eagles. Journal of Ornithology 157, 165–178. https://doi.org/10.1007/s10336-015-1264-8CrossRefGoogle Scholar
Navedo, J.G., Fernández, G., Valdivia, N., Drever, M.C. and Masero, J.A. (2017). Identifying management actions to increase foraging opportunities for shorebirds at semi‐intensive shrimp farms. Journal of Applied Ecology 54, 567–576. https://doi.org/10.1111/1365-2664.12735CrossRefGoogle Scholar
Naylor, R.L., Hardy, R.W., Buschmann, A.H., Bush, S.R., Cao, L., Klinger, D.H. et al. (2021). A 20-year retrospective review of global aquaculture. Nature 591, 551–563. https://doi.org/10.1038/s41586-021-03308-6CrossRefGoogle ScholarPubMed
O’Donnell, W.B. and Debus, S.J.S. (2012). Nest-sites and foraging of the White-bellied Sea-Eagle Haliaeetus leucogaster on the subtropical eastern coast of Australia. Australian Field Ornithology 29, 149–159.Google Scholar
Olsen, J., Debus, S.J.S., Rose, A.B. and Judge, D. (2013). Diets of White-bellied Sea-Eagles Haliaeetus leucogaster and Whistling Kites Haliastur sphenurus breeding near Canberra, 2003–2008. Corella 37, 13–18.Google Scholar
Papastamatiou, Y.P., Iosilevskii, G., Di Santo, V., Huveneers, C., Hattab, T., Planes, S. et al. (2021). Sharks surf the slope: Current updrafts reduce energy expenditure for aggregating marine predators. Journal of Animal Ecology 90, 2302–2314. https://doi.org/10.1111/1365-2656.13536CrossRefGoogle ScholarPubMed
Pattnayak, S.P., Panda, A.K., Prusty, B.A.K., Rout, S. and Jena, P. (2025). Habitat-dependent dietary pattern of white-bellied sea-eagle: a cross-regional meta-analysis. Ornithology Research 33, 31. https://doi.org/10.1007/s43388-025-00238-zCrossRefGoogle Scholar
Pattnayak, S.P. and Prusty, B.A.K. (2022). Observations on the mortality of olive ridley sea turtles (Lepidochelys olivacea) and associated factors along Ganjam coast, east coast of India. Indian Journal of Geo-Marine Sciences 51, 680–687. https://doi.org/10.56042/ijms.v51i08.47146Google Scholar
Paul, A.K., Paul, A., Sardar, J. and Bid, B. (2023). The degradation of coastal habitats in Andhra Pradesh and Tamil Nadu: an environmental approach. In Paul, A.K. and Paul, A. (eds), Crisis on the Coast and Hinterland: Assessing India’s East Coast with Geomorphological, Environmental and Remote Sensing and GIS Approaches. Cham: Springer Nature, pp. 129–142. https://doi.org/10.1007/978-3-031-42231-7_9CrossRefGoogle Scholar
Porej, D. and Hetherington, T.E. (2005). Designing wetlands for amphibians: The importance of predatory fish and shallow littoral zones in structuring of amphibian communities. Wetlands Ecology and Management 13, 445–455. https://doi.org/10.1007/s11273-004-0522-yCrossRefGoogle Scholar
Potter, T.I., Stannard, H.J., Greenville, A.C. and Dickman, C.R. (2018). Understanding selective predation: Are energy and nutrients important? PLOS ONE 13, e0201300. https://doi.org/10.1371/journal.pone.0201300CrossRefGoogle ScholarPubMed
R Core Team (2023). R: A Language and Environment for Statistical Computing (version 4.3.2). Vienna: R Foundation for Statistical Computing. https://www.R-project.org/Google Scholar
Ragavan, P., Kathiresan, K., Mohan, P.M., Ravichandran, K., Jayaraj, R.S.C. and Rana, T.S. (2021). Ensuring the adaptive potential of Coastal wetlands of India- the need of the hour for sustainable management. Wetlands Ecology and Management 29, 641–652. https://doi.org/10.1007/s11273-020-09742-zCrossRefGoogle Scholar
Sekercioglu, C.H. (2006). Increasing awareness of avian ecological function. Trends in Ecology & Evolution 21, 464–471. https://doi.org/10.1016/j.tree.2006.05.007CrossRefGoogle ScholarPubMed
Smith, G.C. (1985). An analysis of prey remnants from Osprey Pandion haliaetus and White-Bellied Sea-Eagle Haliaetus leucogaster feeding roosts. Emu – Austral Ornithology 85, 198–200. https://doi.org/10.1071/MU9850198CrossRefGoogle Scholar
Tapia, L. and Zuberogoitia, I. (2018). Breeding and nesting biology in raptors. In Sarasola, J.H., Grande, J.M. and Negro, J.J. (eds), Birds of Prey. Cham: Springer, pp. 63–94. https://doi.org/10.1007/978-3-319-73745-4_3CrossRefGoogle Scholar
Temeles, E.J. (1985). Sexual size dimorphism of bird-eating hawks: The effect of prey vulnerability. The American Naturalist 125, 485–499. https://doi.org/10.1086/284357CrossRefGoogle Scholar
Thomson, V.K., Stevens, T., Jones, D. and Huijbers, C. (2016). Carrion preference in Australian coastal raptors: Effects of urbanisation on scavenging. Sunbird 46, 16–28. https://search.informit.com.au/documentSummary;dn=667878666004518;res=IELHSSGoogle Scholar
Tobias, J.A., Sheard, C., Pigot, A.L., Devenish, A.J.M., Yang, J., Sayol, F. et al. (2022). AVONET: morphological, ecological and geographical data for all birds. Ecology Letters 25, 581–597. https://doi.org/10.1111/ele.13898CrossRefGoogle ScholarPubMed
van Donk, S., Shamoun-Baranes, J., van der Meer, J. and Camphuysen, K.C.J. (2019). Foraging for high caloric anthropogenic prey is energetically costly. Movement Ecology 7, 17. https://doi.org/10.1186/s40462-019-0159-3CrossRefGoogle ScholarPubMed
Widén, P. (1994). Habitat quality for raptors: A field experiment. Journal of Avian Biology 25, 219–223. https://doi.org/10.2307/3677078CrossRefGoogle Scholar
Wiersma, J. and Richardson, A. (2009). Foraging of white-bellied sea-eagles Haliaeetus leucogaster in relation to marine fish farms in Tasmania. Corella 33, 71–79.Google Scholar
Willer, D.F., Newton, R., Malcorps, W., Kok, B., Little, D., Lofstedt, A. et al. (2024). Wild fish consumption can balance nutrient retention in farmed fish. Nature Food 5, 221–229. https://doi.org/10.1038/s43016-024-00932-zCrossRefGoogle ScholarPubMed
Wood, S.N. (2017). Generalized Additive Models: An Introduction with R, 2nd edn. New York: Chapman and Hall/CRC. https://doi.org/10.1201/9781315370279CrossRefGoogle Scholar
Zhong, Y., Chen, Z.F., Dai, X., Liu, S.S., Zheng, G., Zhu, X. et al. (2018). Investigation of the interaction between the fate of antibiotics in aquafarms and their level in the environment. Journal of Environmental Management 207, 219–229. https://doi.org/10.1016/j.jenvman.2017.11.030CrossRefGoogle ScholarPubMed