Dangerous reptiles

June 28, 2018, University of Freiburg
Estuarine crocodile Credit: Yusuke Fukuda

The southeast Asian island state of East Timor has a problem with crocodiles. Between 2007 and 2014, there was a sharp increase in attacks on humans. Many of these attacks were fatal. Sebastian Brackhane, a research assistant in the Department of Remote Sensing and Landscape Information Systems of the University of Freiburg, has analyzed data on crocodile attacks in relation to a rise in the population of estuarine crocodiles in East Timor. The results of his field study have been published in the Journal of Wildlife Management.

A native of Southeast Asia and the north of Australia, saltwater crocodiles are the largest of all crocodile species, growing to a length of up to six meters. The animals can weigh more than a ton, and unlike other species of crocodile, they can survive in both fresh and salt water. This enables them to cover lengthy distances by sea. The animals have a strong territorial instinct and are extremely aggressive. They attack anything that moves in the water or near the shore—including humans. After being hunted for their hides right up until the 1960s, in the 1970s, the severely reduced population was named a protected species in, among other places, Australia's Northern Territory, which lies about 450 kilometers south of East Timor.

Previously threatened by extinction, protection of the species led to growth in the population. Unfortunately, it was accompanied by a rise in crocodile attacks on humans. However, as in many other Southeast Asian and Oceanian states, there has until now been no comprehensive data on the actual number of attacks in East Timor. In his field study, Brackhane spoke to local fishermen and village elders about incidents involving crocodiles, and developed a database. This showed that since East Timor became independent from Indonesia in 2002, there have been at least 130 attacks—however, a high number of unreported cases must be assumed.

Estuarine crocodile. Credit: Yusuke Fukuda
"The geographic characteristics of the volcanic island means that it only offers very limited habitat to support a larger population. So we wondered where all the crocodiles in East Timor come from," says Brackhane. Surveys of workers on an oil platform in the high seas between East Timor and the Northern Territory found that saltwater crocodiles have often been sighted in the vicinity of the platform. So the researchers developed the hypothesis that the animals may migrate from Australia to East Timor. "We believe that in many areas, the habitat in the Northern Territory has reached maximum carrying capacity and juvenile saltwater crocodiles cross the sea to East Timor to find new habitats," says Brackhane. The origin of the in East Timor still has to be confirmed by a DNA analysis.

However, Brackhane says that it is clear that many nations of Southeast Asia and Oceania has had a problem with estuarine since their stocks have recovered well under conservation. And in East Timor the animals receive even greater protection: inhabitants believe that the island was created from a crocodile, so hunting "Grandfather Crocodile" is strictly prohibited.

Explore further: Malaysia scientists tag Borneo saltwater crocodile

More information: Sebastian Brackhane et al, When conservation becomes dangerous: Human-Crocodile conflict in Timor-Leste, The Journal of Wildlife Management (2018). DOI: 10.1002/jwmg.21497

Related Stories

Malaysia scientists tag Borneo saltwater crocodile

June 29, 2011

Wildlife researchers in Malaysia are to track a saltwater crocodile by satellite, they said Wednesday, in a bid to find out why nearly 40 people have been attacked on Borneo island over a decade.

Borneo's crocodiles 'no longer endangered'

June 28, 2010

Wildlife officials in Malaysian Borneo are pushing to have its saltwater crocodiles removed from a list of endangered animals, saying the reptile's numbers have strongly recovered in recent years.

Quake off Indonesia causes panic in East Timor

February 24, 2013

(AP)—An undersea earthquake has rocked eastern Indonesia, causing panic among residents in neighboring East Timor. There were no immediate reports of injuries or damage.

Australian police hunt killer of giant crocodile

September 22, 2017

A manhunt has begun for the killer of a giant saltwater crocodile in Australia, as authorities warned its death would trigger more aggressive behaviour among younger crocs in the area.

Recommended for you

Droughts could hit aging power plants hard

March 26, 2019

Older power plants with once-through cooling systems generate about a third of all U.S. electricity, but their future generating capacity will be undercut by droughts and rising water temperatures linked to climate change. ...

Cellular microRNA detection with miRacles

March 26, 2019

MicroRNAs (miRNAs) are short noncoding regulatory RNAs that can repress gene expression post-transcriptionally and are therefore increasingly used as biomarkers of disease. Detecting miRNAs can be arduous and expensive as ...

What happened before the Big Bang?

March 26, 2019

A team of scientists has proposed a powerful new test for inflation, the theory that the universe dramatically expanded in size in a fleeting fraction of a second right after the Big Bang. Their goal is to give insight into ...

Probiotic bacteria evolve inside mice's GI tracts

March 26, 2019

Probiotics—which are living bacteria taken to promote digestive health—can evolve once inside the body and have the potential to become less effective and sometimes even harmful, according to a new study from Washington ...

Two new planets discovered using artificial intelligence

March 26, 2019

Astronomers at The University of Texas at Austin, in partnership with Google, have used artificial intelligence (AI) to uncover two more hidden planets in the Kepler space telescope archive. The technique shows promise for ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

pntaylor
not rated yet Jun 28, 2018
"And in East Timor the animals receive even greater protection: inhabitants believe that the island was created from a crocodile, so hunting "Grandfather Crocodile" is strictly prohibited."

Another instance of superstition costing human lives and people creating their own problems.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.