While ecotourism destinations across the State are expecting a rise in footfall, unregulated activities can cause serious ecological consequences including loss of biodiversity.

According to experts, trekking, boating and camping facilities in forest interiors can lead to the spread of invasive alien species that can harm endemic plants. Most wildlife sanctuaries in Kerala are currently witnessing a rising incursion of high-risk varieties that can displace native taxa.

“As per studies conducted by the Kerala Forest Research Institute, various tourism activities can inadvertently introduce invasive alien species to vulnerable ecosystems. Tourists and department staff carry seeds stuck to their clothes and vehicles and disperse it to various parts. The number of the invasive species has increased over the years and all forests in the State are facing the issue. The Wayanad Wildlife Sanctuary is one worst-affected area,” T.V. Sajeev, Senior Principal Scientist, Nodal Center for Biological Invasions, KFRI, told The Hindu.

Researchers found 25 invasive alien plants, including 17 medium and eight high-risk species, in the Shendurney Wildlife Sanctuary during a study conducted six months ago. While the tourism zone shows the highest spread, the survey also reveals the presence of invasive alien species in some core areas with minimum human interference.

Free from predation pressure

“Displaced native vegetations such as Chromolaena odorata are free from predation pressure and inside the forest there is nothing to check their growth. They out-compete other species and we cannot control them without human intervention,” he says.

While Shendurney is not a heavily infested sanctuary, some of the medium-risk plants have a potential to shift their impact into high risk.

Despite the Forest department carrying out routine weeding and restoration measures, the efforts are often insufficient to contain the spread.

“Though many plants cannot survive under dense shade, invasive species such as Mikania micrantha can grow under the canopy, making human intervention mandatory. So we require a systematic approach.”

While scientists recommend regular surveys to identify new incursions and a proper protocol to eradicate or manage the spread, forest officials say most are not practical at the moment.

Surge in visitor volume

“Of late, there has been a surge in visitor volume after the COVID-19-induced lull. Right now there is no protocol for tourists to sterilise their clothing, footwear and hands before entry or disinfect department vehicles after each trip,” says an official.

Apart from remedial measures depending on the degree of invasion and monitoring campsites, trails and fringes, the department is yet to introduce site-specific protocols for visitors.

“Since tourism zones are critical entry points from where such species reach buffer and core zones, an efficient regulatory mechanism is needed for sustainable ecotourism industry to thrive. Compared to other countries, our bio-security measures are quite inadequate and we need stricter interventions,” says Mr.Sajeev.