Herpetology Notes, volume 11: 981-984 (2018) (published online on 26 November 2018)

Boiga guangxiensis Wen, 1998 (: ) feeding on Draco blanfordii in ,

Cameron W. Hodges1, Evan D. Amber2, and Colin T. Strine1,*

Cat ( Boiga) are nocturnal and arboreal Materials and Methods opisthoglyphous colubrids (Greene, 1989), widely The observation occurred on 29 March 2017 at 2230 distributed across , , and Africa h during a visual encounter survey in a limestone forest (e.g., Rodda et al., 1999; Das, 2010; Cogger, 2014). fragment. We conducted the survey from a 2-m-high Little is known about the venom of Boiga , raised walking platform within the Xishuangbanna however, some appear to possess taxon-specific toxins Tropical Botanical Gardens in Xishuangbanna, Yunnan, which they use to immobilize their prey (Mackessy et China (21.9113°N, 101.2821°E, datum WGS 84; al., 2006). Boiga are known to feed on and their elevation 359 m; Fig 1). The landscape around the forest , , and small , but robust data patch is dominated by matrices of rubber plantations and about diet and feeding strategies are lacking for most banana plantations, interspersed with human settlements. species of tropical arboreal snakes (Savidge, 1988; We uploaded the observation location information on Pierce and Pobprasert, 2013). snakes HerpMapper (voucher number: HM 176636), but we (Boiga guangxiensis Wen, 1998) have been observed did not collect the specimens, as we did not have the in (Nguyen et al., 2009; Ryabov and Orlov, permit for collection. We documented the event from 2010; Ziegler et al., 2010) and in Guangxi Province, China (Wen, 1998). They frequently inhabit primary and secondary tropical forests associated with karsts, and may be found near , in trees 2–5 m above ground (Ryabov and Orlov, 2010). Captive individuals are known to eat birds, , and mice, and faecal samples from wild-caught specimens have contained feathers, fur, and scales (Ryabov and Orlov, 2010). However, their diet and feeding behaviours have not been described in situ. We here report of a B. guangxiensis on an adult Blandford’s flying (Draco blanfordii Boulenger, 1885) in Yunnan, China.

1 Suranaree University of Technology, 111 Thanon Maha Figure 1. We observed the predation event in a fragmented Witthayalai, Suranari, Mueang, District, limestone forest in Xishuangbanna, Yunnan, China, Nakhon Ratchasima, 30000. approximately 23 km northeast of the border and 2 Sakaerat Environmental Research Station, 1 Moo 9, Udom 35 km west of the border. The larger map illustrates the Sap, Wang Nam Khiao District, Nakhon Ratchasima, whole of China, while the smaller map in the upper left corner Thailand 30370. gives a closer look at Yunnan Province. The yellow circle * Corresponding author. E-mail: [email protected] represents Xishuangbanna’s location within Yunnan, China. 982 Cameron W. Hodges et al.

Figure 2. (A) The initial strike by the Boiga guangxiensis individual, targeting the back of the head of the Draco blanfordii. (B) Immediately after the initial strike, the lizard was very active and repeatedly attempted to escape from the . (C) At time 3:30 min after the initial strike, the lizard was no longer breathing or responsive, likely due to the venom of the B. guangxiensis.

the initial strike through ingestion and retreat behaviour We refrained from shining bright light in the direction with both video and photographs. of the snake and lizard in order to avoid disturbing their natural behaviour. After the snake struck we Results began taking occasional photos with flash in order to We spotted the snake wrapped around a tree document the progression of the event, and the snake approximately 4 m above ground with its head pointed continued feeding. We estimated the snake to be 1 m in towards the ground. After noticing the snake and lizard total length, and the tree diameter at breast height to be in the tree, we stopped moving and readied our cameras. 30 cm. The snake approached the resting D. blanfordii Boiga guangxiensis feeding on Draco blanfordii in Yunnan, China 983

Figure 3. (A) The Boiga guangxiensis began to swallow the Draco blanfordii headfirst at time 6:30 min after the Draco presumably died. (B) The snake ingested the Draco by a “jaw-walking” method over a period of 8:43 min. (C) The snake moved up the tree with the Draco tail hanging from its mouth while rapidly tongue flicking for a period of 2:17 min.

from above and struck the lizard behind the head at 2230 Discussion h. We determined the lizard was dead 3:30 min after the Our observation confirms that B. guangxiensis strike, at the time when its eyes closed and movement and respiration ceased (Fig 2). The snake then began naturally feed on lizards, and specifically on arboreal D. repositioning and ingesting the lizard headfirst (Fig 3). blanfordii, in Yunnan, China. However, the composition The total time of the event, including completion of and percentage of B. guangxiensis diet comprised of prey handling and a shift towards avoidance behaviour, lizards is still unknown. This observation also confirms was 25:38 min. that at least some individuals are sometimes active and 984 Cameron W. Hodges et al. potentially opportunistic arboreal nocturnal foragers. Savidge, J.A. (1988): Food habits of Boiga irregularis, an Furthermore, our observation extends the range of introduced predator on . Journal of Herpetology 22 (3): B. guangxiensis to include Yunnan Province. This 275–282. Wen, Y. (1998): Description of a new species of the genus Boiga highlights a need for standardized and quantified survey (Serpentes: Colubridae) from China. Sichuan Journal of Zoology efforts in potential habitats to determine connectivity 17 (2): 51–52. [In Chinese] between populations and their status. Our observation Ziegler, T., Orlov, N.L., Giang, T.T., Truong, N.Q., Tao, N.T., occurred in a forest fragment surrounded by large Quyet, L.K., Khoi, N.V., Thanh, V.N. (2010): New records plantation forests and human settlements, indicating of cat snakes, Boiga Fitzinger, 1826 (Squamata, Serpentes, that some populations of B. guangxiensis may be at Colubridae), from Vietnam, inclusive of an extended diagnosis risk to habitat loss or genetic isolation. If this species of Boiga bourreti Tillack, Le & Ziegler, 2004. Zoosystematics and Evolution 86 (2): 263–274. is determined to be in need of protection, it would be critical to understand the distribution and natural requirements of B. guangxiensis to best implement conservation practices.

Acknowledgments. We would like to thank the Chinese Academy of Sciences for allowing us to conduct a non-invasive survey within the Xishuangbanna Nature Reserve, the Xishuangbanna Tropical Botanical Gardens (XTBG) for hosting us during our stay in China, and Suranaree University of Technology for their support. We would also like to express our thanks to our colleagues for their help: to A. Hughes for organizing and hosting our stay in Xishuangbanna, to K. Messenger for providing a pre- submission peer review, and to A. Chornelia, Y.J. Huan, J. Lei, B. Marshall, and T. Knierim for their contribution in preparing this article.

References

Cogger, H. (2014): Reptiles and Amphibians of Australia. Seventh Edition. Collingwood, Victoria, Australia, CSIRO Publishing. Das, I. (2010): A Field Guide to the Reptiles of South-East Asia. London, United Kingdom, New Holland Publishers. Greene, H.W. (1989): Ecological, evolutionary, and conservation implications of feeding biology in Old World cat snakes, genus Boiga (Colubridae). Proceedings of the California Academy of Sciences 46 (8): 193–207. Mackessy, S.P., Sixberry, N.M., Heyborne, W.H., Fritts, T. (2006): Venom of the Brown Treesnake, Boiga irregularis: ontogenetic shifts and taxa-specific toxicity. Toxicon 47 (5): 537–548. Nguyen, V.S., Ho, T.C., Nguyen, Q.T. (2009): Herpetofauna of Vietnam. Frankfurt am Main, Germany, Edition Chimaira. Pierce, A.J., Pobprasert, K. (2013): Nest predators of Southeast Asian evergreen forest birds identified through continuous video recording. Ibis 155 (2): 419–423. Rodda, G.H., Fritts, T.H., McCoid, M.J., Campbell, E.W., III (1999): An overview of the biology of the brown treesnake (Boiga irregularis), a costly introduced pest on Pacific islands. In: Problem Snake Management: the Habu and the Brown Treesnake, p. 44–80. Rodda, G.H., Sawai, Y., Chiszar, D., Tanaka, H., Eds., Ithaca, New York, USA, Cornell University Press. Ryabov, S.A., Orlov, N.L. (2010): Reproductive biology of Boiga guangxiensis Wen, 1998 (Serpentes: Colubridae). Asian Accepted by Philipp Wagner Herpetological Research 1 (1): 44–47.