Understanding dietary differences in Indian dugongs through opportunistic gut sampling of stranded individuals

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Authors

  • Sumit Prajapati
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India
  • Chinmaya Ghanekar
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India
  • Sameeha Pathan
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India
  • Rukmini Shekar
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India
  • K. Madhu Magesh
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India
  • Swapnali Gole
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India
  • Srabani Bose
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India
  • Sweta Iyer
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India
  • Anant Pande
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India; 2Marine Programme, Wildlife Conservation Society – India, Bengaluru 560 097, India
  • Kuppusamy Sivakumar
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India; Department of Ecology and Environmental Sciences, School of Life Sciences, Pondicherry University, Puducherry 605 014, India
  • Jeyaraj Antony Johnson
     Wildlife Institute of India, Chandrabani, Dehradun 248 001, India

DOI:

https://doi.org/10.18520/cs/v123/i10/1259-1264

Keywords:

Dugongs, foraging pattern, megaherbivore, necropsy, seagrass.

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Volume 123, Issue 10, November 2022 || RESEARCH COMMUNICATIONS

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Prajapati, S., Ghanekar, C., Pathan, S., Shekar, R., Magesh, K. M., Gole, S., … Johnson, J. A. (2022). Understanding dietary differences in Indian dugongs through opportunistic gut sampling of stranded individuals. Current Science, 123(10), 1259–1264. https://doi.org/10.18520/cs/v123/i10/1259-1264
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We analysed gut samples of stranded dugongs from Tamil Nadu and Gujarat, India, to understand their die­tary preferences. We quantified seagrass fragments from the gut as leaf, stem and rhizome, and identified leaf fragments up to genera level by their morphological features and epidermal cell characteristics using an in­verted microscope. The overall abundance of above-ground fragments (leaf, stem) was higher in all samples, which may suggest the dugongs use a cropping mechanism to forage. The ingested seagrass generic diversity was higher in Tamil Nadu (n = 5) dugong individuals than those in Gujarat (n = 2). A total of five genera were recorded from all samples, viz. Halophila spp., Halodule spp., Cymodocea spp., Enhalus sp. and Syringodium spp. In Tamil Nadu, Cymodocea spp. (46.24%) was the most dominant, followed by Halophila spp. (26.49%), Syringodium spp. (14.83%) and Halodule spp. (12.16%), with a low occurrence of Enhalus spp. (0.19%). In Gujarat, Halodule spp. (61.48%) was the most dominant, followed by Halophila spp. (30.20%). The recorded plastic and wood fragments suggest fine spatial scale threat mapping in dugong habitats

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