By the early twentieth century, unregulated sport hunting and land conversion for tea and agriculture had reduced the Indian rhinoceros to a few scattered pockets, with surviving numbers estimated around 200 individuals confined mainly to what is now Assam and Nepal.
Strict protection, anti-poaching patrols and habitat management in reserves such as Kaziranga National Park allowed numbers to climb steadily across the twentieth century. Current estimates put the global population above 4,000, with the majority concentrated in Kaziranga alone, making it one of the more geographically concentrated large-mammal recoveries on record.
What is less settled is how secure this recovery actually is: because so much of the population sits in one river system prone to flooding, and because poaching for horn persists at low levels, conservationists debate whether the current status reflects genuine long-term security or a fragile concentration risk. Historical population figures from before organised counts also vary between sources and should be read as estimates rather than censuses.