Jackal population has decreased 60% during last 20 yrs in SL
By Rathindra Kuruwita
The population of Sri Lankan jackals has dropped by about 60 percent during the last two decades and this is an indication of serious problems in the Sri Lankan environment, Prof. Sampath S. Seneviratne, of the Department of Zoology and Environment Sciences, University of Colombo has said.
Prof. Seneviratne, one of the authors of the research study, titled ‘The Way of the Jackal’, said that jackals and their cousins, the fox and the wolf, were spreading rapidly in other parts of the world, especially in Western Europe.
Prof. Seneviratne said Sri Lankans did not hunt the jackal for meat or its fur/skin. There are hardly any negative interactions between humans and jackals in Sri Lanka, he added.
“We have been conducting research on jackals. We have looked at their population across the country. We found that the jackal population has dropped by about 60 percent in the last 20 years. What’s going on? Are they the canaries in the mine who tell us that something awful is taking place in our environment?”
Prof. Seneviratne said farmers in some parts of the country told them that the jackal population has dropped, following the widespread use of pesticides.
“Humans live about 70 years and a jackal usually lives for about 10 years. They eat things that are identical to what we eat. The jackal eats rice, jackfruit, coconuts, etc. If you give your plate of rice and curries to a jackal, he or she will eat it. They also eat mice, frogs and small animals that are found in the forest and agricultural lands. When animals die after being exposed to pesticides, the jackals often eat the carcasses because he is a scavenger.”
Prof. Seneviratne said they had also carried out autopsies of many dead jackals. It is possible that eating small animals that have been killed by pesticides might be leading to the deaths of jackals.
“A lot of veterinarians told us that in the wet zone, they encounter jackals with distemper. This virus initially attacks the cells of the immune system, weakening an animal’s immune response and putting it at higher risk of other infections. Later their hind legs become paralyzed and then they die. The veterinarians think domestic dogs develop distemper and this is then spread to jackals,” he said.
On the other hand the ‘ovitas’ in the paddy fields, the chenas, the shrubland and the rubber lands in the wet zone are being cleared. The jackals dig burrows and raise their pups in them. They also keep away from dogs, who usually attack them. Thus, they usually have burrows in a semi-cleared area close to the village and with the gradual destruction of such areas, the habitat of jackals are being destroyed.
“The jackals and farmers are not in conflict. Jackals eat the animals that are a nuisance to farmers. They eat serpents, rodents, peacock eggs, small pigs, etc. He is a great balancer of the ecosystem. When the jackal population drops, we can assume the balance in the ecosystem has collapsed. In parallel, we see a spike in peacock population.”
Prof. Seneviratne said the proliferation of peacocks in the wet zone was quite recent and Sri Lankans must realise that it was the jackals that had kept the peacock population in check and had relegated them to the dry zone.
Prof. Seneviratne said that peacock eggs were vulnerable to other animals, but adult peacocks were without any threats from other animals. “The jackal eats peacock eggs and kill their young. Since the jackal population has dropped, the peacock population has exploded,” he said, adding that they were now conducting a research to determine if the Sri Lankan jackal (canis aureus nariya) was an indigenous species.
Prof. Seneviratne said that the tiger was the animal with most tourist attraction. It is followed by the panda, elephant, lion and the leopard.
“A lot of tourists come to Sri Lanka to see leopards and the value of a leopard in Yala has been estimated at 43 million rupees. In the United States the tourism value of the wolf, the big brother of the jackal, is estimated at 171,000 dollars. The jackal is the little brother of the wolf, but we have not marketed this animal at all,” he said, adding that there were only a few instances where the Sri Lankan jackal had attacked humans. That happens especially when jackals contract rabies from domesticated dogs.
“In 2020, the anti-rabies campaign came to a standstill. In 2019, it was also affected due to the Easter Sunday attacks. Thus, cases of rabies increased and in Horana some jackals got infected by domestic dogs. Those jackals came to the village and bit a few villagers. Two people died and 32 jackals were killed by village dogs when they strayed into the village,” he said.
