Pen culture as a climate adaptive strategy to enhance fish production in wetlands

What is it about?

Wetlands are an important source of livelihood for fishermen in developing countries. The Eastern and Northeastern regions of India are home to many wetlands, where commercially important species of fish thrive. Sadly, the number and diversity of fish in these wetlands has reduced due to climate change. In West Bengal, the Mathura wetland suffers from growth of excess aquatic plants, low quality water, and sedimentation. This has led to a sharp decline in the number of Carps—a type of high-value fish, and important indigenous species in the wetland. This study’s authors checked if climate-resistant pen culture could improve the production of Carps in this wetland and increase the fishermen’s ability to adapt to climate change. Pen culture is the practice of growing fish in a volume of water known as a pen, which is closed on all three sides except the bottom. It is known to be effective in water bodies choked by aquatic plants, and in flood-like conditions. The authors found that important carp species grown via pen culture in the Mathura wetland displayed an 82% survival rate. The specie Gibelion catla displayed the highest weight gain, growth rate, and daily average growth, closely followed by other species. Within 90 days of pen culture, 380 kg of carp fingerlings, i.e., juvenile carps were retrieved from the pens. Upon release into the wetland, they displayed better survival than those that grew in the wild.

Featured Image

Photo by Sara Kurfeß on Unsplash

Photo by Sara Kurfeß on Unsplash

Why is it important?

Pen culture can restore the population of high-value fish and indigenous species in wetlands, especially in flood-prone wetlands of Assam and Bihar. Thus, it can improve the livelihoods of fishermen in areas affected by climate change. It can also be integrated with plant-culture methods to improve the diversity of wetlands. Moreover, it is economical, user-friendly, and climate-resilient, making it suitable as a climate-adaptation measure. KEY TAKEAWAY: Pen culture is a cost-effective method which gives fishermen the capacity to adapt to climate change by restoring the growth of high-value fish and diversity in the wetlands of India.