ArticlePublisher preview available

Saltwater crocodile (Crocodylus porosus) attacks in East Nusa Tenggara, Indonesia

Marine and Freshwater Research

February 2021
72(7):978-986

DOI:10.1071/MF20237

Authors:

Brandon Sideleau

Charles Darwin University

Saltwater crocodiles (Crocodylus porosus) are extensively distributed throughout South-east Asia, including the Indonesian province of East Nusa Tenggara (ENT), and they account for hundreds of attacks on people annually. Recorded incidents not only tell us where crocodiles are found (useful when survey data are limited), but importantly can improve our understanding of causal factors to better address risk. We compiled public attack records for ENT on humans from 2009 to 2018 using an online database of incidents (CrocBITE), then worked closely with government representatives to visit human–crocodile conflict (HCC) hot spots, where some unreported attack records were collected, and local attitudes towards crocodiles could be assessed. Of the 100 attacks we compiled, 60% were fatal incidents. Most victims were male (84%) and most attacks (75%) occurred during fishing. West Timor had the highest proportion of attacks (70%). Cultural attitudes towards crocodiles were found to be generally positive throughout ENT, similar to neighbouring Timor-Leste, although recent media stories appear to have introduced some negative beliefs and fears. We recommend that resources and training are made available to improve local crocodile knowledge, including habitat surveys in proximity to conflict areas, plus community-based education where the risk of crocodile attack is high.

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Saltwater crocodile (Crocodylus porosus) attacks in

East Nusa Tenggara, Indonesia

Brandon Sideleau

,Tamen Sitorus

,Dadang Suryana

and

Adam Britton

CrocBITE, PO Box 353, Humpty Doo, NT 0836, Australia.

Directorate General of Nature Resources and Ecosystem Conservation, Ministry of Environment

and Forestry of the Republic of Indonesia, Gedung Manggala Wanabakti, Block I, 8th Floor,

Jalan Jenderal Gatot Subroto, Jakarta Pusat 10270, Jakarta, Indonesia.

Research Institute for the Environment and Livelihoods, Charles Darwin University, NT 0810,

Australia.

Big Gecko Crocodilian Research, PO Box 353, Humpty Doo, NT 0835, Australia.

Corresponding author. Email: bsideleau@gmail.com

Abstract. Saltwater crocodiles (Crocodylus porosus) are extensively distributed throughout South-east Asia, including

the Indonesian province of East Nusa Tenggara (ENT), and they account for hundreds of attacks on people annually.

Recorded incidents not only tell us where crocodiles are found (useful when survey data are limited), but importantly can

improve our understanding of causal factors to better address risk. We compiled public attack records for ENT on humans

from 2009 to 2018 using an online database of incidents (CrocBITE), then worked closely with government

representatives to visit human–crocodile conflict (HCC) hot spots, where some unreported attack records were collected,

and local attitudes towards crocodiles could be assessed. Of the 100 attacks we compiled, 60% were fatal incidents. Most

victims were male (84%) and most attacks (75%) occurred during fishing. West Timor had the highest proportion of

attacks (70%). Cultural attitudes towards crocodiles were found to be generally positive throughout ENT, similar to

neighbouring Timor-Leste, although recent media stories appear to have introduced some negative beliefs and fears.

We recommend that resources and training are made available to improve local crocodile knowledge, including habitat

surveys in proximity to conflict areas, plus community-based education where the risk of crocodile attack is high.

Received 4 August 2020, accepted 28 November 2020, published online 8 February 2021

Introduction

The saltwater crocodile (Crocodylus porosus) of South-east

Asia and Oceania is considered the largest extant crocodilian

species (Britton et al. 2012) and the most wide ranging (Buden

and Haglelgam 2010;Grigg and Kirshner 2015). Favouring tidal

habitat, where tides and currents greatly assist migration

(Campbell et al. 2010), significant populations can also be found

in non-tidal freshwater habitat and inland freshwater swamps

(Grigg and Kirshner 2015). Breeding populations in some parts

of their range have been recorded up to 1000 km inland

(Bezuijen et al. 2005) and C. porosus is often sympatric with

predominantly freshwater crocodilian species (Hollands 1982;

Frazier 2000;Letnic and Connors 2006). Across its range, there

are many recorded attacks of C. porosus on people (e.g. 169

attacks in 2019, 80 of them fatal; see CrocBITE worldwide

crocodilian attack database at http://www.crocodile-attack.info,

accessed 1 January 2021). The real number is likely even higher

because many attacks from certain countries go unreported;

however, data from countries with good records suggest that

attacks are increasing over time as crocodile and human popu-

lations grow (Britton and Campbell 2013).

East Nusa Tenggara (ENT; Indonesian Nusa Tenggara

Timur) is the southern-most Indonesian province located at the

eastern-most portion of the Lesser Sunda Islands. It comprises

21 regencies, including the Flores, Sumba and Timor groups.

East Timor (Timor-Leste) gained independence in 1975. The

historical presence of C. porosus in ENT is well documented and

the species is of similar cultural significance throughout the

province as it is in Timor-Leste. During the late 18th century,

French military personnel reported that a virgin woman would

be sacrificed to a crocodile on the beaches of Kupang whenever

a new ruler came to power. This practice apparently ceased

during the 19th century (Boomgaard 2007). Today, C. porosus is

known to occur throughout the province (Balai Besar Konser-

vasi Sumber Daya Alam, pers. comm.), although formal popu-

lation surveys are few, limited to key areas along the southern

coast of West Timor (Menipo Island and Maubesi mangrove)

and in Kupang Bay (Kayat et al. 2016;Fig. 1). Recent informa-

tion on occurrence in unsurveyed areas can be gleaned in other

ways, including regularly documented human–crocodile con-

flict (HCC) records (CrocBITE, see http://www.crocodile-

attack.info) and local knowledge. Consequently, crocodile

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Marine and Freshwater Research, 2021, 72, 978–986

https://doi.org/10.1071/MF20237

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Biology and Evolution of Crocodylians is a comprehensive review of current knowledge about the world's largest and most famous living reptiles. Gordon Grigg's authoritative and accessible text and David Kirshner's stunning interpretive artwork and colour photographs combine expertly in this contemporary celebration of crocodiles, alligators, caimans and gharials. This book showcases the skills and capabilities that allow crocodylians to live how and where they do. It covers the biology and ecology of the extant species, conservation issues, crocodylian–human interaction and the evolutionary history of the group, and includes a vast amount of new information; 25 per cent of 1100 cited publications have appeared since 2007. Richly illustrated with more than 500 colour photographs and black and white illustrations, this book will be a benchmark reference work for crocodylian biologists, herpetologists and vertebrate biologists for years to come. Winner of the 2015 Whitley Medal.

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Saltwater crocodile (Crocodylus porosus) attacks in East Nusa Tenggara, Indonesia

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