Research article: Jathanna, D., Karanth, K. U., Kumar, N. S., Karanth, K. K., & Goswami, V. R. (2015). Patterns and determinants of habitat occupancy by the Asian elephant in the Western Ghats of Karnataka, India. PloS One, 10(7), e0133233. https://doi.org/10.1371/journal.pone.0133233
Key highlights
- 60% of the world’s wild elephants are found in India, and the Western Ghats are one of the last remaining homes of these gentle giants
- The study area in the Western Ghats spans 38,000 square kilometers, covering diverse habitat types including forests, tree plantations, savanna, shrub savanna, grasslands, and private lands
- During the dry seasons, researchers conducted “detection—non-detection” surveys in 188 square kilometer grids
- Asian elephants occupy 13,483 km², which is 64% of the 21,167 km² of available habitat and the detection probability of seeing elephant signs lies between 56% to 88%
- The study area includes 14 protected areas covering 5,500 square kilometers, in a region with a population of over 10.2 million people
- Human activities such as agricultural expansion, human settlements, and other disturbances are the primary factors influencing elephant habitats, rather than natural factors like rainfall or forest type
India harbors nearly 60% of the world’s wild elephants, still, the species is now restricted to limited, fragmented areas due to increasing agricultural expansion, human settlements, and developmental projects over the past two to three centuries. The lush, green expanse of the Western Ghats in Karnataka, India, is not just a hotspot for biodiversity but also one of the last few homes of the majestic Asian elephant. Despite their grandeur and cultural significance, these gentle giants face an uncertain future.
The present knowledge about the distribution of Asian elephants comes from previous studies that used varied methods, such as dung encounter rates, direct observation, and telemetry-based locations. However, none of these methods accounted for the fact that animals are not always detected during fieldwork for various reasons. Additionally, there is a clear lack of a standard protocol, resulting in a gap in the scientific base needed for their conservation and management. To address these challenges, the authors conducted an extensive study across the Western Ghats. Their research sheds light on where elephants roam and how the environment and human activities influence their occurrence, using state-of-the-art statistical models previously employed to assess the distribution of tigers and dholes. This study provides crucial insights for the conservation of Asian elephants.
In a vast area spanning 38,000 square kilometers of the Western Ghats, the team surveyed forests, tree plantations, savanna, shrub savanna, grasslands, and private lands. After carefully studying previous research articles on the distances traveled by elephants in search of food, the team divided the study area into 188 square kilometers grids and employed a technique called “detection—non-detection” surveys. Instead of counting each elephant, they looked for signs like footprints and droppings during the dry seasons (October-May) of 2005–2006 and 2006–2007 to ensure there was no change in dung persistence due to rainfall. This method, combined with sophisticated modeling, allowed them to estimate the presence of elephants even when they were not directly visible.
The study revealed that Asian elephants occupy 13,483 km² (SE = 847 km²), corresponding to 64% of the available 21,167 km² of elephant habitat in the study landscape. This indicates that they have a strong presence in the region, but there’s more to the story. The detection probability, which indicates how likely it is to detect signs of elephant presence such as dung or hoofprints, varied from 56% to 88%. Without accounting for this variability in detection, their distribution would be underestimated by 2,116 km² or 16%. One might think that natural factors like rainfall or forest type would be the main drivers of where elephants live. Surprisingly, the study found that human activities were the primary determinants. Agricultural expansion, human settlements, and other disturbances heavily influenced elephant habitats. In this humid region, even rainfall wasn’t a limiting factor but it was the human footprint that mattered the most.
The study landscape includes 14 protected areas spread across 5,500 square kilometers, nestled within a region home to over 10.2 million people. These elephant habitats face numerous threats, including illegal hunting, livestock grazing, and forest biomass extraction. Additionally, they are under pressure from development projects and industrial growth. The findings underscore the urgent need to manage human activities in and around elephant habitats. Simple steps like regulating land use and minimizing disturbances can make a significant difference. The study also highlights the importance of using advanced methods to understand wildlife distribution, ensuring that conservation efforts are based on accurate data.
This research not only maps where elephants currently live but also sets a benchmark for future studies. By studying where elephants are found and how this changes over time, we can track their movements and update conservation plans as needed. This is especially important in a rapidly changing world where habitat loss and human-wildlife conflicts are on the rise. In conclusion, the work by Jathanna and his team offers a beacon of hope for the Asian elephant in the Western Ghats. By revealing the intricate relationship between these magnificent animals and their environment, it paves the way for informed and effective conservation efforts. Protecting the giants of the Western Ghats requires a delicate balance of human and ecological considerations—one that this study brings into sharp focus.
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