Invasive freshwater fish in the Ganges

Invasive freshwater fish in the Ganges

Subject: Environment

Section: Climate Change

Context: Regional climate model studies in the Ganges River basin predict an increase in the mean annual temperature by 1 to 4 degrees Celsius between 2010 and 2050.This steep incline could potentially open up newer parts of the Ganges River to non-native species.

Concept:

• Most invasive species are able to adapt to changing climatic conditions due to the morphological plasticity which enable them to respond to new environments by changing their anatomical traits.
• Invasive fish are particularly prone to escaping from their pens and ponds. They also easily take hold in newer areas and can out-compete many local fish.
• Among the most abundantly captured invasive species that may benefit from rising temperatures are the common carp or Eurasian carp (Cyprinus carpio), Nile tilapia (Oreochromis niloticus) and African catfish (Clariasgariepinus).
• India’s National Biodiversity Authority (NBA) lists the Nile tilapia, African catfish and common carp as a great threat to the country’s freshwater biodiversity. These species are present in abundance, and farmed along the Ganges, given their high commercial value. However, according to the NBA, the introduction of these fish has critically depleted many native species, especially Indian carps, in major riverine systems, including the Ganges.
• Despite being widely documented as invasive, these species continue to be cultured world-over. For example, a study published by the Food and Agriculture Organization of the United Nations (FAO) in 2021 observed that global Tilapia Aquaculture production grew exponentially from 1990 to 2018, from 380,000 tonnes to six million tonnes, making it the fourth-largest species group in global aquaculture.
• However, the impacts of climate change – primarily rising temperatures – will only enable non-natives to thrive and spread. In the long term, they would have an adverse effect on the local ecosystem since they have the potential to interfere with ecological niches, biodiversity and can build their own environment to thrive in, thus disrupting ecosystem services.

To know about Biological Diversity Act, kindly refer: https://optimizeias.com/biological-diversity-act-2002/