Human effect on genetic connectivity in mammalsDate: 05 January 2020 Tags: Biodiversity
A new study from the National Centre for Biological Sciences (NCBS), Bengaluru, has revealed that anthropogenic activities can impact genetic connectivity or the movement among habitat patches usually resulting in mating and genetic exchange.
Changing landscapes, habitat loss, fragmentation, and global climate change have been listed as the main reasons for biodiversity decline worldwide.
In several mammalian carnivores, juveniles disperse away from their mother's territory to establish their own territory. Males are known to travel longer distances than females.
Isolation of habitat patches (due to habitat destruction and fragmentation) can restrict animal movement among habitat patches and thus reduce genetic exchange and increase the probability of extinction.
Four wide-ranging mammals, Jungle cats, leopards, sloth bears, tigers, were investigated for the genetic differentiation in central India, which is a critical landscape for several species.
The team looked at how land-use, human population density, nearby roads and traffic affected the genetic structure. The paper notes that tigers were impacted the most by high human footprint.
Tigers in central India do not have equally high genetic exchange throughout the landscape, eventhough they have known travel a long distance.
Jungle cats were found to be the least impacted. That is likely because in central India, they occupy a variety of habitats including forests, scrublands, grasslands and even irrigated agricultural fields close to the forests.
India has started paying attention to wildlife corridors and encouraging engineering reforms to promote wildlife movements.
The Ministry of Environment along with the Wildlife Institute of India released a document that lays out the regulatory requirements for developing roads, railways, powerlines while recognising the impacts on wildlife and people.
With increasing infrastructure and traffic, systematically studying the impact of roads on smaller species like jungle cat and jackals and ensuring the presence of mitigation structures like underpasses and overpasses would be crucial to ensure that we don't fragment the currently well-connected populations.