IRCF REPTILES & AMPHIBIANS • 27(1):91–93 • APR 2020

Observations of Australian Red-bellied Blacksnakes (Pseudechis porphyriacus)

Preying on Freshwater EelsMatthew Mo1, Peter Hayler2, and Antonia Hayler2

1P.O. Box A290, Sydney South, New South Wales 1232, Australia (matthew.sk.mo@gmail.com)2Choosypix Photography, Oatley, New South Wales 2223, Australia (choosypix@yahoo.com.au)

Photographs by Peter and Antonia Hayler.

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IRCF REPTILES & AMPHIBIANS • VOL15, NO 4 • DEC 2008 189TABLE OF CONTENTS

T A B L E O F C O N T E N T S

F E A T U R E A R T I C L E S

Chasing Bullsnakes (Pituophis catenifer sayi) in Wisconsin: On the Road to Understanding the Ecology and Conservation of the Midwest’s Giant Serpent ...................... Joshua M. Kapfer 190

The Shared History of Treeboas (Corallus grenadensis) and Humans on Grenada: A Hypothetical Excursion ............................................................................................................................Robert W. Henderson 198

R E S E A R C H A R T I C L E S

The Texas Horned Lizard in Central and Western Texas ....................... Emily Henry, Jason Brewer, Krista Mougey, and Gad Perry 204 The Knight Anole (Anolis equestris) in Florida

.............................................Brian J. Camposano, Kenneth L. Krysko, Kevin M. Enge, Ellen M. Donlan, and Michael Granatosky 212

C O N S E R V A T I O N A L E R T

World’s Mammals in Crisis ............................................................................................................................................................. 220 More Than Mammals ...................................................................................................................................................................... 223 The “Dow Jones Index” of Biodiversity ........................................................................................................................................... 225

H U S B A N D R Y

Captive Care of the Central Netted Dragon ....................................................................................................... Shannon Plummer 226

P R O F I L E

Kraig Adler: A Lifetime Promoting Herpetology ................................................................................................ Michael L. Treglia 234

C O M M E N T A R Y

The Turtles Have Been Watching Me ........................................................................................................................ Eric Gangloff 238

B O O K R E V I E W

Threatened Amphibians of the World edited by S.N. Stuart, M. Hoffmann, J.S. Chanson, N.A. Cox, R. Berridge, P. Ramani, and B.E. Young .............................................................................................................. Robert Powell 243

CONSERVATION RESEARCH REPORTS: Summaries of Published Conservation Research Reports ................................. 245 NATURAL HISTORY RESEARCH REPORTS: Summaries of Published Reports on Natural History ................................. 247 NEWBRIEFS ...................................................................................................................................................................................... 248 EDITORIAL INFORMATION ..................................................................................................................................................... 251 FOCUS ON CONSERVATION: A Project You Can Support ............................................................................................... 252

Front Cover. Shannon Plummer.Totat et velleseque audant mo estibus inveliquo velique rerchil erspienimus, quos accullabo. Ilibus aut dolor apicto invere pe dolum fugiatis maionsequat eumque moditia erere nonsedis ma sectiatur ma derrovitae voluptam, as quos accullabo.

Back Cover. Michael KernTotat et velleseque audant mo

estibus inveliquo velique rerchil erspienimus, quos accullabo. Ilibus

aut dolor apicto invere pe dolum fugiatis maionsequat eumque

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IRC

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REPTILES & AMPHIBIANSC O N S E R V AT I O N A N D N AT U R A L H I S T O R Y

Copyright © 2020. Matthew Mo. All rights reserved.

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The Red-bellied Blacksnake (Pseudechis porphyriacus) is a medium to large elapid of eastern Australia, commonly

associated with moist areas (Wilson and Swan 2017). The species’ diet is comprised primarily of frogs, but it also preys on small reptiles, birds, and mammals (Shine 1991; Cogger 2018). Some sources (Victorian Department of Environment,

Land, Water and Planning 2017; Australian Museum 2019; Queensland Museum 2019; University of Melbourne 2019) also list fish as a component of the diet; however, we are unaware of any published accounts of Red-bellied Blacksnakes hunting and catching fish. Herein we report two opportu-nistic observations of this species preying on freshwater eels.

Fig. 1. A Red-bellied Blacksnake (Pseudechis porphyriacus) swimming energetically near the center of a small pond.

Fig. 2. The Red-bellied Blacksnake (Pseudechis porphyriacus) moving onto the bank.

IRCF Reptiles & Amphibians ISSN 1098-6324

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Both occurred in the constructed Lime Kiln Bay Wetland in Oatley, New South Wales, Australia. Red-bellied Blacksnakes are frequently encountered at this site (Mo 2015). At 1540 h on 10 October 2013, we observed a Red-bellied Blacksnake extended over a small ephemeral stream. The snake was approximately 1.5 m long and the amount of water flowing through the creek was a few centimeters deep and no more than 1 m wide. The snake was station-ary for 10 min until a Longfin Eel (Anguilla reinhardtii), approximately 1 m in length, approached the snake. As the eel passed the snake, the latter bit and held onto the eel behind its head. The eel thrashed briefly before becoming immobile. The snake then released the eel momentarily before moving to the eel’s head and swallowing the catch in a few minutes. The snake remained at the site for the remainder of the observation. At 1025 h on 10 November 2019, we observed another Red-bellied Blacksnake swimming vigorously around the cen-ter of a small pond (Fig. 1). This snake was also about 1.5 m in length. For approximately 5 min, the snake dove and sur-faced repeatedly. At one point, a Longfin Eel that was larger than the snake appeared to pursue it, at which time the snake briefly left the water (Fig. 2), possibly to escape the larger eel.

The snake then returned to and continued to hunt in the water and, after one dive, resurfaced holding a 40-cm Shortfin Eel (A. australis) at midbody (Fig. 3). The snake repeatedly bit the eel along its length as it carried it closer to the bank. Once out of the water, the snake dragged its catch under some low vegetation (Fig. 4) and consumed it. These observations appear to represent two different hunting strategies. In the first instance, the snake was station-ary along a shallow creek line where it apparently ambushed the eel (e.g., Olivier et al. 2014) or perhaps made the catch opportunistically. The second observation most likely repre-sented an active foraging attempt, in which the snake moved around the pond searching for prey (e.g., Kojima and Mori 2015). Interestingly, this snake released the eel several times to inflict additional bites. In both observations, the prey was motionless and presumably dead when consumed. In the second observation, the catch occurred a few min-utes after the snake was apparently pursued by a larger Longfin Eel. This might have been inquisitive behavior as the eel’s size precluded it from being threatened by the snake. Alternatively, the eel could have been pursuing the snake as a potential prey item. The latter interpretation suggests that the predator-prey relationship between snakes and eels is reciprocal.

IRCF REPTILES & AMPHIBIANS • 27(1):91–93 • APR 2020MO ET AL.

Fig. 3. A Shortfin Eel (Anguilla australis) held by the mid-body before the Red-bellied Blacksnake (Pseudechis porphyriacus) bites it repeatedly.

Fig. 4. The Red-bellied Blacksnake (Pseudechis porphyriacus) dragged the dead Shortfin Eel (Anguilla australis) onto the bank to swallow it on land.

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IRCF REPTILES & AMPHIBIANS • 27(1):91–93 • APR 2020MO ET AL.

Literature CitedAustralia Museum. 2019. Red-bellied Black Snake. <https://australianmuseum.net.

au/learn/animals/reptiles/red-bellied-black-snake>.

Cogger, H. 2018. Reptiles and Amphibians of Australia. Seventh Edition. CSIRO Publishing, Collingwood, Victoria, Australia.

Kojima, Y. and A. Mori. 2015. Active foraging for toxic prey during gestation in a snake with maternal provisioning of sequestered chemical defences. Proceedings of the Royal Society B 282: 20142137.

Mo, M. 2015. Herpetofaunal community of the constructed Lime Kiln Bay Wetland, south Sydney. Victorian Naturalist 132: 64–72.

Olivier, L., G.E.A. Gartner, and F. Brischoux. 2014. Ambush or active life: Foraging mode influences haematocrit levels in snakes. Biological Journal of the Linnean Society 111: 636–645.

Queensland Museum. 2019. Red-bellied Black Snake Pseudechis porphyriacus. <https://www.qm.qld.gov.au/Find+out+about/Animals+of+Queensland/Reptiles/Snakes/Common+and+dangerous+species/Red-bellied+Black+Snake#.XfSD72QzY2w>.

Shine, R. 1991. Why do larger snakes eat larger prey items? Functional Ecology 5: 493–502.

University of Melbourne. 2019. Black snakes (Pseudechis spp.). <https://biomedi-calsciences.unimelb.edu.au/departments/pharmacology/engage/avru/dis-cover/snakes/dangerous-venomous-snakes-of-major-medical-importance/black-snakes-pseudechis>.

Victorian Department of Environment, Land, Water and Planning. 2017. Red-bellied Black Snake. <https://www.wildlife.vic.gov.au/__data/assets/pdf_file/0016/84112/Red-bellied-Black-Snake.pdf>.

Wilson, S. and G. Swan. 2017. A Complete Guide to Reptiles of Australia. Fifth Edition. New Holland Publishers, Sydney, New South Wales, Australia.