Manas National Park Witnesses a Rhino Revival: 35 Births Signal Hope for a Species Once Lost from the Landscape

A decade of relocation and rehabilitation efforts in Assam has helped re-establish the one-horned rhinoceros population, but poaching risks, habitat management and genetic diversity remain critical conservation priorities.

(SDNA) Assam: A remarkable conservation story is unfolding at Manas National Park in Assam, where the greater one-horned rhinoceros is gradually rebuilding its presence after disappearing from the landscape. Years of coordinated efforts to relocate rhinos from other protected areas and rehabilitate rescued animals appear to be yielding encouraging results.

According to a study, 35 rhino births were recorded in Manas between 2012 and 2021, including calves born to females from the first generation of rhinos raised in the park. The emergence of a locally born generation is an important indicator that the animals are adapting to their restored habitat and beginning to establish a sustainable population.

Rebuilding a Lost Population Through Conservation

Spread across Assam’s Chirang and Baksa districts, Manas National Park shares its northern boundary with Bhutan’s Royal Manas National Park. Various conservation initiatives, including the Indian Rhino Vision 2020 programme, have sought to restore the rhinoceros population in this ecologically significant landscape.

Between 2008 and 2021, 22 one-horned rhinoceroses were relocated to Manas from Kaziranga National Park and Pobitora Wildlife Sanctuary. In a parallel effort, 20 rhinos were released into the park’s natural environment from a wildlife rehabilitation centre between 2006 and 2021.

The objective was not simply to increase rhino numbers but to establish a population capable of surviving and reproducing in the wild. The latest study suggests that animals brought into Manas through relocation and rehabilitation have adapted to local conditions and are contributing to population growth.

Thirty-Five Calves in a Decade: The Next Generation Emerges

The study recorded 35 births during the period under review. Of these, 19 calves were born to females relocated from other protected areas, while nine were born to rehabilitated females. Five calves were born to females from the first generation of rhinos born in Manas. The mothers of two additional calves could not be identified.

Wildlife biologist Deba Kumar Dutta, a member of the IUCN Asian Rhino Specialist Group, has highlighted reproduction and the birth of calves as important evidence that the reintroduced rhinos are adapting to their new surroundings.

The study also found a notable difference in the age at which females gave birth for the first time. Females born in Manas reportedly had their first calves at an average age of 5.65 years, compared with 9.2 years among rehabilitated females.

The greater one-horned rhinoceros has a relatively slow reproductive cycle. Females generally reach reproductive maturity between five and seven years of age. Gestation lasts approximately 15 to 16 months, and a female typically gives birth to one calf at a time. The interval between births is commonly two to three years, making sustained population recovery a long-term undertaking.

Monsoon Months See a Higher Number of Births

The research also identified a seasonal pattern in rhino births. Fourteen of the 35 recorded births occurred between May and September, coinciding with the monsoon season.

During these months, the availability of water and fresh vegetation generally increases. These conditions may influence rhino movements, habitat use and reproductive activity, although seasonal patterns alone do not establish a direct cause for the births.

Annual figures varied considerably. Manas recorded nine births in 2013, while no births were documented in 2016. The numbers subsequently improved, with five calves recorded in 2020 and seven in 2021.

Researchers monitored the animals through radio telemetry, very-high-frequency (VHF) collars, camera traps and field observations. Tracking females and their calves helped the team gather information about breeding, movement patterns and habitat use.

Different Origins, Different Patterns of Habitat Use

The study found that the average home ranges of rhinos varied according to their origin and rehabilitation history.

Rhinos relocated from other protected areas had an average home range of approximately 339 square kilometres. Rehabilitated animals occupied a considerably smaller average range of around 52 square kilometres, while the first generation born in Manas had an average range of approximately 79 square kilometres.

Researchers have observed that rhinos raised in rehabilitation facilities may sometimes venture close to human settlements. Animals captured in natural habitats and relocated to another forest, by contrast, may retain more typical wild behaviours.

Another noteworthy observation involved first-generation females giving birth in areas also used by their mothers. This suggests that certain patterns of habitat use may persist across generations, although further research would help establish how consistently such behaviour is inherited or learned.

Poaching and Inbreeding Remain Serious Concerns

Despite the encouraging births, the recovery of Manas’s rhino population remains vulnerable. During the early years covered by the study, several adult male rhinos were killed by poachers. Such losses can reduce breeding opportunities and affect the sex ratio within a small population.

Genetic diversity presents another long-term challenge. When a population remains small, closely related animals may breed with one another, increasing the risk of inbreeding. Over time, this can reduce genetic variation and potentially weaken a population’s ability to adapt to environmental changes and disease pressures.

Wildlife expert Yadvendradev Jhala has emphasised the need for sustained conservation, noting that the rhino’s slow life cycle makes rapid population recovery difficult. Coordinated management of Manas’s rhinos alongside populations in Kaziranga, Pobitora and other rhino habitats in West Bengal could help maintain genetic diversity and strengthen the long-term prospects of the species.

Protecting the Habitat Is Essential for Lasting Recovery

Experts have called for continued monitoring, improved habitat management and the possible relocation of additional rhinos from other protected areas, where scientifically appropriate. Managing grasslands by removing invasive plant species and ensuring access to water throughout the year are also considered important measures.

The birth of a new generation of rhinos in Manas represents a significant milestone in the park’s conservation journey. However, births alone cannot guarantee long-term survival. Effective anti-poaching measures, suitable habitat, scientific population monitoring and the preservation of genetic diversity will remain essential.

The experience of Manas demonstrates that a wildlife population lost from a landscape can begin to recover through planned reintroduction, scientific monitoring and sustained conservation efforts. Ensuring that this progress endures will require protecting not only the animals themselves but also the ecological conditions that allow future generations to survive and thrive.

(SDNA) — News Behind the Truth