Herpetology Notes, volume 14: 537-538 (2021) (published online on 18 March 2021)

Predation attempt on a rice paddy , , by the Indian bullfrog, tigerinus (Daudin, 1803), at Patharia Hill Reserve Forest, Moulvibazar,

Tanvir Ahmed1, Hassan Al-Razi1, Habibon Naher1,*, and Sabir Bin Muzaffar2

Amphibians consume a wide range of small prey, The victim attempted to move away by jerking its limbs, including both vertebrates and invertebrates (e.g., while the predator used its left forelimb to more firmly IUCN Bangladesh 2015). Anurophagy has been seize its prey and started swallowing. The abdomen reported in at least 228 (Measey et al., 2015). of the prey was observed to swell, likely due to the The Indian bullfrog (Anura: predator’s strong jaw pressure, and eventually popped ) is a voracious feeder, consuming a open, with its intestines becoming visible (Fig. 1B). variety of prey including invertebrates, small vertebrates, The attempt at swallowing continued until the predator mammals, and birds (Padhye et al., 2008). There are released the prey at 21:32 h, without apparent external few studies available on the diet of H. tigerinus in stimulus. Due to security issues related to the activities Bangladesh and anurophagy is generally not known well of the Border Guards Bangladesh, we were unable to from this country. Mohanty and Measey (2018) reported 358 species as prey items of H. tigerinus (including some anurans) from Andaman Island, , where it is considered as an invasive species. Hoplobatrachus tigerinus was reported to consume a Rhacophorus malabaricus in southern India (Mishra, 2017) and teraiensis in eastern (Gautam and Bhattarai, 2020). The tadpole of H. tigerinus was also reported to scavenge on dead (Vyas, 2013). Here, we report on an opportunistic observation of a predation attempt by a juvenile H. tigerinus on Fejervarya sp. (Anura: Dicroglossidae) at Patharia Hill Reserve Forest in northeastern Bangladesh. On 26 June 2019 at 20:22 h, a rice paddy frog, genus Fejervarya, was observed jumping on sloping concrete stairs at the local Border Guards Bangladesh office on the edge of Patharia Hill Reserve Forest (Lathitila), Moulvibazar, Bangladesh (24.5321°N, 92.2261°E; details in Ahmed et al., 2020). A juvenile H. tigerinus jumped at the Fejervarya and caught its left hind limb in its maw, biting up to the level of the thigh (Fig. 1A).

1 Department of Zoology, Jagannath University, Dhaka 1100, Figure 1. Predatory attempt by a juvenile Indian bullfrog, Bangladesh. Hoplobatrachus tigerinus, on a rice paddy frog, genus 2 United Arab Emirates University, PO Box 17551, Al Ain, Fejervarya, at Patharia Hill Reserve Forest, Bangladesh. United Arab Emirates. (A) The bullfrog is firmly holding the struggling rice paddy * Corresponding author. E-mail: [email protected] frog. (B) The intestine of the victim is seen spilling out of its © 2021 by Herpetology Notes. Open Access by CC BY-NC-ND 4.0. abdomen due to the predator’s jaw pressure. 538 Tanvir Ahmed et al. remain and continue making observations. Before our References departure, we confirmed that both individuals were Ahmed, T., Hasan, S., Naher, H., Muzaffar, S.B. (2020): Record alive, positioned alongside each other. of Great Woolly Horseshoe Bat (Rhinolophus luctus, Temmick The situation where frogs eat other frogs is often the 1834) [sic] in Northeast Bangladesh. Journal of Bat Research & subject of anecdotal observation (e.g., Toledo et al., Conservation 13(1): 40–44. 2007). Moreover, this kind of predator-prey relationship Boelter, R.A., Kaefer, I.L., Both, C., Cechin, S. (2012): Invasive is not understood well for most participating species bullfrogs as predators in a neotropical assemblage: what frog species do they eat? Biology 62: 397–408. (Mishra, 2017). Body size of adult frogs has been treated Emerson, S.B. (1985): Skull shape in frogs: correlations with diet. as a dominant predictor of anurophagy (Wells, 2007). Herpetologica 41(2): 177–188. Larger mouth gape could be as important as overall Glorioso, B.M., Waddle, J.H., Crockett, M.E., Rice, K.G., Percival, size in consumption of frogs by frogs (Emerson, 1985; H.F. (2012): Diet of the invasive Cuban Treefrog (Osteopilus Boelter et al., 2012). Juveniles of species that attain a septentrionalis) in pine rockland and mangrove habitats in South large adult size may eat a large proportion of anurans Florida. Caribbean Journal of Science 46: 346–355. (e.g., Osteopilus septentrionalis – Glorioso et al., 2012). Gautam, B., Bhattarai, S. (2020): Notes on anurophagy by bullfrogs, Hoplobatrachus spp. (Anura: Dicroglossidae) in Eastern Nepal. At the same time, there exists a number of large-bodied IRCF Reptiles & 27(1): 77–78. anurans (including toads), which have no frogs in their IUCN Bangladesh. (2015): Red List of Bangladesh. Volume 4. diet. In fact, the circumstances under which frogs eat Reptiles and Amphibians. Dhaka, Bangladesh, International frogs are complex and synergistic, depending on habitat, Union for the Conservation of Nature, Bangladesh Country species diversity, invasiveness, and size (Measey et al., Office. 2015). Measey, G.J., Vimercati, G., Villiers, F.A., Mokhatla, M.M., Davies, There is a paucity of studies on anurophagy to reveal S.J., Edwards, S., Altwegg, R. (2015): Frog eat frog: exploring variables influencing anurophagy. PeerJ 3(2): e1204. how widespread it is in H. tigerinus. Both H. tigerinus Mishra, S.B. (2017): Natural history notes. Hoplobatrachus and various Fejervarya or Minervarya species are tigerinus. Diet. Herpetological Review 48(1): 162. abundant within their distributions in Bangladesh, and Mohanty, N.P., Measey, J. (2018): What’s for dinner? Diet and they share almost similar habitats (IUCN Bangladesh, potential trophic impact of an invasive anuran Hoplobatrachus 2015), and anurophagy may be common but unnoticed. tigerinus on the Andaman archipelago. PeerJ 6(10): e5698. Mohanty and Measey (2018) suggested that, as an Padhye, A., Manamendra-Arachchi, K., de Silva, A., Dutta, S., ambush predator, H. tigerinus consumes a relatively Shrestha, T.K., Bordoloi, S., et al. (2008): Hoplobatrachus tigerinus. The IUCN Red List of Threatened Species. e.T5830 high quantity of terrestrial vertebrates. Therefore, a 1A11760496. Accessed on 5 July 2019. detailed study on H. tigerinus anurophagy is required Toledo, L.F., Ribeiro, R., Haddad, C.F. (2007): Anurans as prey: in order to understand and quantify the effect on an exploratory analysis and size relationships between predators indigenous populations, particularly in some and their prey. Journal of Zoology 271: 170–177. ecologically important areas of the world where H. Wells, K.D. (2007): The Ecology and Behavior of Amphibians. tigerinus has been introduced. We encourage additional Chicago, Illinois, USA, University of Chicago Press. studies on H. tigerinus and its diet in the forest habitats Vyas, R. (2013): Note on the tadpole of Indian Bullfrog Hoplobatrachus tigerinus scavenging on Ornate Narrow- of Bangladesh to understand the effect on the native mouthed Frog Microhyla ornata. Frog Leg, Newsletter of the amphibian fauna. Amphibian Network of South Asia and the Amphibian Specialist Group South Asia 19: 3–4. Acknowledgements. We thank Stephen Mahony for helping with species identification and Santosh Bhattarai for pre- peer reviewing the manuscript. We acknowledge the financial assistance of the United States Fish and Wildlife Service (Project ID: F19AP00130), and the Bangladesh Forest Department for issuing research permits. We thank the Department of Zoology, Jagannath University, and the Department of Biology, United Arab Emirates University, for facilitating the project.

Accepted by Hinrich Kaiser