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An analysis of tomistoma (Tomistoma schlegelii) attacks on humans

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Marine and Freshwater Research
Authors:
Brandon Sideleau at Charles Darwin University
Brandon Sideleau
Agata Staniewicz at Bat Conservation Trust
Agata Staniewicz
Murian Syah
Murian Syah
Murian Syah
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Kyle J Shaney at Texas A&M University – Kingsville
Kyle J Shaney
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Abstract

Context Increasing human–crocodile conflict (HCC) is a major conservation and management issue. Although three species are responsible for most attacks, on occasion, some slender-snouted species, such as tomistoma (Tomistoma schlegelii), are also implicated. Aims To analyse reports of confirmed and suspected attacks on humans by tomistoma and explore potential causes and solutions. Methods Reports of attacks were collected for the CrocBITE project from January 2010 to December 2019, utilising media reports and communication with local authorities. Attack trends, including outcome, victim demographics and activities, geographic location, and other details were analysed. Key results We recorded 31 attacks, including 10 deaths, where the culprit species was confirmed or strongly suspected to be a tomistoma. The Jambi province of Sumatra was the site of most attacks and most victims were male and fishing at the time. In addition, most attacks were reported during the 3-year period from 2016 to 2018. Conclusions On rare occasions, tomistoma prey upon humans. Certain anthropogenic factors may be altering tomistoma behaviour and contributing to increased conflict. Implications Tomistoma were recently up listed from Vulnerable to Endangered on the IUCN Red List and this conflict is yet another threat facing the species, alongside the destruction habitat.
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RESEARCH PAPER
https://doi.org/10.1071/MF22015
An analysis of tomistoma (Tomistoma schlegelii) attacks on
humans
Brandon SideleauA,*, Agata StaniewiczB, Murian SyahCand Kyle J. ShaneyD
For full list of author affiliations and
declarations see end of paper
*Correspondence to:
Brandon Sideleau
CrocBITE, 2536 Avenida De Las Plantas,
Thousand Oaks, CA 91360, USA
Email: bsideleau@gmail.com
Handling Editor:
Max Finlayson
Received: 20 January 2022
Accepted: 7 August 2022
Published: 29 August 2022
Cite this:
Sideleau B et al. (2022)
Marine and Freshwater Research,73(11),
1331–1339.
doi:10.1071/MF22015
© 2022 The Author(s) (or their
employer(s)). Published by
CSIRO Publishing.
ABSTRACT
Context. Increasing human–crocodile conflict (HCC) is a major conservation and management
issue. Although three species are responsible for most attacks, on occasion, some slender-
snouted species, such as tomistoma (Tomistoma schlegelii), are also implicated. Aims. To analyse
reports of confirmed and suspected attacks on humans by tomistoma and explore potential
causes and solutions. Methods. Reports of attacks were collected for the CrocBITE project
from January 2010 to December 2019, utilising media reports and communication with local
authorities. Attack trends, including outcome, victim demographics and activities, geographic
location, and other details were analysed. Key results. We recorded 31 attacks, including 10
deaths, where the culprit species was confirmed or strongly suspected to be a tomistoma. The
Jambi province of Sumatra was the site of most attacks and most victims were male and fishing
at the time. In addition, most attacks were reported during the 3-year period from 2016 to
2018. Conclusions. On rare occasions, tomistoma prey upon humans. Certain anthropogenic
factors may be altering tomistoma behaviour and contributing to increased conflict.
Implications. Tomistoma were recently up listed from Vulnerable to Endangered on the IUCN
Red List and this conflict is yet another threat facing the species, alongside the destruction habitat.
Keywords: conservation, HCC, human–wildlife conflict, reptiles, tomistoma, Tomistoma schlegelii,
wetlands.
Introduction
The International Union for Conservation of Nature (IUCN) defines human–wildlife conflict
(HWC) as occurring when wildlife poses a danger to human lives or livelihoods, resulting in
human populations persecuting the species. This persecution often involves direct killing or
even eradication efforts. Large predators, such as big cats and crocodilians, and large
herbivores, such as elephants and hippos, are the species groups most often affected.
HWC is a pressing conservation and natural resource management issue that is increasing
due to numerous factors, including human population growth and the increase in associated
land use, the depletion of natural prey species, and the rebounding populations of some
large predator species (Pooley 2015; Pooley et al. 2017). Owing to these factors, as well
as better record keeping in remote locations (Sideleau et al. 2021), some species that
were not historically considered a threat to human safety are now being implicated in
more attacks on humans. Crocodilians are known to be responsible for more human
deaths worldwide annually than any other large wild animal (Gates 2014). Three
species in particular are responsible for the vast majority of reported human deaths
caused by crocodile attacks: the Nile crocodile (Crocodylus niloticus) of Africa, the
saltwater crocodile (Crocodylus porosus) of South-East Asia and Oceania, and the
mugger crocodile (Crocodylus palustris) of South Asia. Occasionally, however, other
species are implicated in human injuries and deaths. In the New World, for example, the
American crocodile (Crocodylus acutus) is responsible for the most reported human
injuries and deaths, but to a much lesser extent than the aforementioned Old-World
species (Sideleau and Britton 2013)(Fig. 1a). On even rarer occasions, slender-snouted
... The absence of reports of T. schlegelii entanglement in fishing gear is thought to be due to its shyness and tendency to habitat away from human activity [28,43,56]. However, this does not guarantee that T. schlegelii will not come into conflict with humans, as evidenced by the record of crocodile attacks on humans, most of which have occurred in western Indonesia [57]. ...
... Human presence might trigger behavioral change in this species [59][60][61][62], thus making it more aggressive. These behavioral changes are influenced by anthopogenic factors [57], such as illegal fishing practices. Findings also confirm that fishermen using electrofishing devices have caused the death of crocodile hatchlings. ...
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