Culling Sabah's crocodiles will not reduce croc attacks

Close up of the snout of the 'Crocodylus porosus'. Due to the increase in crocodile attack reports in Sabah, people are under the assumption that the crocodile population in Sabah has increased to a level that requires drastic measures, such as culling. — RUDI DELVAUX/Danau Girang Field Centre

THE recent surge of crocodile attacks in Sabah has caused concern among many parties, including the public, local communities living alongside rivers, and governmental bodies.

Due to the increase in crocodile attack reports, people are under the assumption that the crocodile population in Sabah has increased to a level that requires drastic measures, such as culling.

A three-year state-wide crocodile survey was carried out from 2017 to 2019 to assess the distribution and abundance of crocodiles in Sabah. Following this, a model was simulated to determine the impact of crocodile culling or removal on the survival of the species. The modelling revealed that culling would be detrimental to the survival of the crocodile population in Sabah.

No doubt, the culling of individual crocodiles that have been deemed unsafe or dangerous to the public can be undertaken only if absolutely necessary and with the permission of appropriate authorities, but even when this is done, it does not result in safer waters.

Reducing the size of the crocodile population by culling does not lead to reduced risks of crocodile attacks as it only takes one individual for an attack to take place. Hence, the assumption that the culling of crocodiles will reduce the population size and therefore, reduce the risk of attacks, is undeniably a mistake. This assumption, in fact, creates a false sense of security among the public into thinking that rivers are safer with a reduced number of crocodiles.

To add to this, Sarawak, despite issuing almost 100 permits for crocodile culling to reduce the risks of conflict, has called the operation “negligible” as the people of Sarawak are still using rivers as a source of income and livelihood, and there are continuous reports of crocodile attacks.

In another example, culling operations that were widely carried out in Mozambique to solve human-crocodile conflict have been labelled as “completely ineffective” by its government.

Most problematic crocodiles are typically large males that are relatively hard to catch. So, culling operations end up targeting smaller and less dangerous individuals. Besides that, there will always be more crocodile habitats upstream or downstream, so even if you think you can cull all problematic crocodiles in one area, there will still be other crocodiles that eventually become problematic.

There have been over 250 people killed by crocodiles in Indonesia since 2018 despite Indonesia having a significantly lower density of crocodiles than Australia, where crocodile populations are the largest in the world but attacks on humans are very rare.

The bottom line is that there is very little association between the number of crocodiles that exist and the number of attacks that occur, suggesting that culling is a rather irrelevant solution to eradicating human-crocodile conflict.

In fact, the culling of large crocodiles from a river system could potentially create “power vacuums” into which younger and more ferocious males move in.

What is really needed is a combination of the strategic relocation of crocodiles from areas where there is high probability of contact with humans, to designated crocodile zones where there is no contact with humans; and public education.

The main reason Australia has been able to achieve low attack rates is due to its very effective relocation/ management plan and education programmes.

Unfortunately, most rivers in Sabah are utilised and occupied by local communities, and removing all crocodiles from all the rivers is impossible. To add to this, designating crocodile zones is a complex process that requires a lot of resources. The transportation of crocodiles to distant, excluded areas is very challenging. This does not yet cover the facets of genetic integrity when identifying potential crocodile zones.

On top of this, relocated crocodiles have been found returning to their old territory, swimming through formerly crocodile-free rivers. This could be a reason as to why there have been numerous sightings of large crocodiles in unexpected places, including waterways in the city. Moving local communities out of river zones is also not practical, neither is it economical.

Our only solution to overcoming human-crocodile conflict is public awareness and education.

Crocodiles are a commonly recognised threat to humans. Therefore, attacks should be easy to prevent if people knew how to function and act in a crocodile-occupied river. People must be aware of where you can and can’t swim, while accepting the fact that any river could be crocodile territory and we have to abide by their rules.

Crocodiles are still a vulnerable species in Sabah and the only real solution to eliminating crocodile attacks is to stay away from them. It is absolutely crucial that this liability remains solely that of humans, as we can’t expect crocodiles, or any animal for that matter, to choose not to attack.

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Prof Benoit Goossens (Cardiff University) is the director of the Danau Girang Field Centre in Sabah and member of the IUCN Crocodile Specialist Group, while Sai Kerisha Kntayya is a PhD student at Cardiff University who led the 2017-2019 crocodile survey in Sabah.