GUWAHATI Overlapping prey availability or habitat suitability could dictate a positive association between dholes and tigers, facilitating co-existence or even cooperative behaviours between the two species of carnivores, a new study has found.
The dhole or Asiatic wild dog (Cuon alpinus) is the only endangered wild pack-living canid in the tropical Indian forests and is considered at high risk of extinction.
The study through camera traps by Urjit Bhatt and Salvador Lyngdoh in western Assam’s Manas National Park also revealed that the diurnal activity of the dholes had the highest temporal overlap with leopards and the lowest with clouded leopards.
The two scientists are associated with the Department of Landscape Level Planning and Management at the Dehradun-based Wildlife Institute of India. Their paper titled ‘Do dholes segregate themselves from their sympatrids? Habitat use and carnivore co‑existence in the tropical forest’ was published in the latest issue of Mammalian Biology, a peer-reviewed international scientific journal edited by the German Society for Mammalian Biology.
Sympatric refers to animals, plant species, and populations within the same or overlapping geographical areas.
The scientists studied the dholes in three phases from April 2017 to May 2019 in the 500 sq. km Manas National Park, a UNESCO World Heritage Site. This park and the adjoining Royal Manas National Park in Bhutan form one of the largest areas of conservation significance in South Asia, representing the full range of habitats from the subtropical plains to the alpine zone.
The range of habitats in the cross-border national park is ideal for the dholes.
Fragmented population
Operating in packs of 5-10 individuals — larger groups of more than 30 were observed in 2004 — dholes were once widespread across southern and eastern Asia. Factors such as habitat loss, declining prey availability, persecution, disease, and interspecific competition have contributed to the ongoing fragmentation of its populations.
The global population of adult dholes, now classified as endangered on the International Union for Conservation of Nature’s Red List, is estimated to be between 949 and 2,215 individuals, scattered in localised areas of India and Thailand.
“We aimed to assess the relative abundance index, habitat use and factors (space and time) influencing dhole co-existence with other sympatric carnivores in Manas National Park,” the study, testing five hypotheses, said.
The hypotheses included conflict with humans on the periphery of protected areas as the primary threat to dholes, higher habitat utilisation where small-medium prey species such as rodents, hares, and rhesus macaques, and a negative relationship between dhole habitat use and other large carnivores.
“However, our study findings revealed a surprising positive relationship between dhole habitat use and tiger, rejecting the habitat exclusivity hypothesis. This unexpected result challenges the assumption of antagonistic interactions between these two species and suggests a more complex ecological dynamic,” the study said.
“The positive association could be attributed to factors such as overlapping prey availability or habitat suitability, which may facilitate co-existence or even cooperative behaviours between dholes and tigers,” the study said, suggesting further research to unravel the mechanisms underlying this positive relationship.
“Good habitats and forests are like wildlife mega cities or hotspots which provide many niches and possibilities. This is why places like Manas are important and any disruption will wipe out such ecological balance we often do not understand,” Dr. Lyngdoh told The Hindu.
