The tiger’s silent killers | India News
India has lost nearly Rs 8.3 trillion in the last 60 years to 10 invasive alien species like lantana camara and prosopis juliflora, which are affecting over 500 sq km every year
What Covid has proved to be for humans, lantana camara, and prosopis juliflora are for tiger ecosystems. As we debate 50 years of Project Tiger, little is being done to eliminate these silent killers to restore tiger habitats.
A study by evolutionary biologist Alok Bang reveals India has lost nearly Rs 8.3 trillion in the last 60 years to 10 invasive alien species.
In August 2020, research by three Wildlife Institute of India (WII) scientists — Ninad Mungi, Qamar Qureshi, and YV Jhala — found that over 3 lakh sq km (44%) of Indian forests is affected by lantana. The survey was conducted in 2009-2010 in the forests of Shivalik Hills in the north, Central India, and the southern Western Ghats.
Mungi, currently a fellow at Aarhus University, Denmark, said, “Over 60% area in tiger reserves is invaded, spreading at a rate of over 500 sq km per year. These have a complex effect on native biodiversity, where we see them providing habitat cover for wildlife and food for many animals.”
A recent paper by the WII team in Kanha tiger reserve evaluated these impacts on tiger ecosystems. Lead author Rajat Rastogi says, “Invasive plants have multiple impacts. In Kanha, these plants changed soil nutrients, altering plant density.” Native plants like amla, chironji, shatavar, and many grass species, which are nutritious forage for wild herbivores and important crops for local communities, declined.
Rastogi, an independent ecologist, says, “Native food plants can be reduced, depleting herbivores and hurting tigers. Tigers would move to relatively less invaded areas, maybe even killing livestock.”
“Forest departments are focusing on lantana removal but ecological restoration is needed,” says GD Muratkar, the ‘Grassman of India’.
“The solutions are complex. A few tiger reserves like Bandipur, MP Pench, and Biligiri Rangaswamy (Karnataka) are so invaded by woody plants that suddenly removing all leaves wildlife without habitat cover. Moreover, recovery of native plants is challenging. Invasive plants keep reappearing,” says Mungi.
Removal of invasive plants is also damaging to native biodiversity. Bulldozing plants from large areas needs a scientific restoration plan. “We suggest, first safeguard relatively un-invaded areas and increase this systematically. This guarantees maximum returns with minimal resources,” Mungi says. However, despite a history of failures, there has been no experiment on managing invasions, Mungi laments. “How can scientists imagine what is to be done overnight? There is a desperate need to experiment with restoration first,” said Mungi. “Most PAs invest in removing invasive plants but there is no systematic approach and documentation. So, the same sites are managed again and again,” he said.
“Also, invasive plants adapt. A management technique may not work in all habitats,” says Rastogi. Reserves like Kanha and Tadoba are trying to systematize invasive plant control but there is a need to streamline it scientifically. We need to restore native biodiversity, not merely remove invasive plants.
What Covid has proved to be for humans, lantana camara, and prosopis juliflora are for tiger ecosystems. As we debate 50 years of Project Tiger, little is being done to eliminate these silent killers to restore tiger habitats.
A study by evolutionary biologist Alok Bang reveals India has lost nearly Rs 8.3 trillion in the last 60 years to 10 invasive alien species.
In August 2020, research by three Wildlife Institute of India (WII) scientists — Ninad Mungi, Qamar Qureshi, and YV Jhala — found that over 3 lakh sq km (44%) of Indian forests is affected by lantana. The survey was conducted in 2009-2010 in the forests of Shivalik Hills in the north, Central India, and the southern Western Ghats.
Mungi, currently a fellow at Aarhus University, Denmark, said, “Over 60% area in tiger reserves is invaded, spreading at a rate of over 500 sq km per year. These have a complex effect on native biodiversity, where we see them providing habitat cover for wildlife and food for many animals.”
A recent paper by the WII team in Kanha tiger reserve evaluated these impacts on tiger ecosystems. Lead author Rajat Rastogi says, “Invasive plants have multiple impacts. In Kanha, these plants changed soil nutrients, altering plant density.” Native plants like amla, chironji, shatavar, and many grass species, which are nutritious forage for wild herbivores and important crops for local communities, declined.
Rastogi, an independent ecologist, says, “Native food plants can be reduced, depleting herbivores and hurting tigers. Tigers would move to relatively less invaded areas, maybe even killing livestock.”
“Forest departments are focusing on lantana removal but ecological restoration is needed,” says GD Muratkar, the ‘Grassman of India’.
“The solutions are complex. A few tiger reserves like Bandipur, MP Pench, and Biligiri Rangaswamy (Karnataka) are so invaded by woody plants that suddenly removing all leaves wildlife without habitat cover. Moreover, recovery of native plants is challenging. Invasive plants keep reappearing,” says Mungi.
Removal of invasive plants is also damaging to native biodiversity. Bulldozing plants from large areas needs a scientific restoration plan. “We suggest, first safeguard relatively un-invaded areas and increase this systematically. This guarantees maximum returns with minimal resources,” Mungi says. However, despite a history of failures, there has been no experiment on managing invasions, Mungi laments. “How can scientists imagine what is to be done overnight? There is a desperate need to experiment with restoration first,” said Mungi. “Most PAs invest in removing invasive plants but there is no systematic approach and documentation. So, the same sites are managed again and again,” he said.
“Also, invasive plants adapt. A management technique may not work in all habitats,” says Rastogi. Reserves like Kanha and Tadoba are trying to systematize invasive plant control but there is a need to streamline it scientifically. We need to restore native biodiversity, not merely remove invasive plants.
