Raising biodiversity concerns in the wetlands of Upper Kuttanad, an invasive plant known as Malayan Hanguana is rapidly spreading throughout the backwater areas of Kumarakom panchayat. The aquatic plant, scientifically named Hanguana anthelminthica, is commonly found in the coastal regions of Southeast Asian countries.
Belonging to the family of Hanguanaceae, Malayan Hanguana is a large, perennial plant that poses a significant threat to local biodiversity and human life in the region. The dense growth of Malayan Hanguana creates ideal conditions for dangerous reptiles, putting human lives at risk.
In 2020, Anoop P Balan, an assistant professor with the botany department of BAM College, Pathanamthitta, and N S Pradeep, a senior scientist with the Malabar Botanical Garden, Kozhikode, were the first to identify the presence of this invasive plant in Kumarakom. According to them, that marked the first reported instance of the plant’s invasion in India, specifically in the Kumarakom-Vembanad backwaters, with the plant primarily establishing itself in the Kumarakom and Muhamma regions.
Following reports of its presence, scientists from the Kerala Agriculture University (KAU) and the Krishi Vigyan Kendra, Kumarakom, recently conducted a visit to the Ithikkayal area in Kumarakom to assess the situation further. The team consisted of P Prameela, professor and principal investigator, All India Coordinated Research Project on Weed Control, KAU, Savitha Antony, assistant professor, AICRP, and G Jayalekkshmi, professor and head, Krishi Vigyan Kendra, Kottayam.
Hanguana anthelminthicas are helophytes that thrive in marshes, partially submerged in water and sprout from buds beneath the water’s surface. These unique plants can reach heights of up to 3 metres. They are distinguished by their long, fleshy, giant leaves that can grow to 1-2 metres tall, emerging from the waterlogged basal rhizomatous stem. Local residents have indicated that the infestation of this plant began as early as 2001 and has since spread to cover an area of approximately 2.50 acres.
The new invasive plant spotted at Ithikkayal in Kumarakom
Speaking to TNIE, Prameela expressed concerns about the spread of these plants. “Initially, we were exploring the possibility of utilising the plant for various purposes such as making fibre. However, this plant poses a significant threat to the region and should be eradicated promptly,” she said.
Moreover, the rapid growth and aggressive spread of Malayan Hanguana can outcompete native aquatic vegetation, leading to a decline in biodiversity. Its evergreen nature ensures it retains foliage year-round, making it difficult for other plants to establish themselves in areas it dominates. As a fast-growing aquatic plant, Hanguana anthelminthica can obstruct water flow and hinder fishing and transportation.
The scientists recommended the implementation of effective management strategies to control and eradicate the spread of the weed.
This includes physically removing the weed using an excavator and ensuring proper disposal through composting, with the active participation of the local community and self-government. Additionally, regular monitoring and removal of any regrowth of the plant must be carried out over 3-4 years to completely eradicate the weed from the area, they said.