Rivers have been crucial to human civilization, yet much remains unknown about their giant inhabitants. The world's largest freshwater fish was identified in 2022 when a 661-pound stingray was caught in Cambodia's Mekong River, surpassing the previous record held by a giant catfish. This discovery is part of fish biologist Zeb Hogan's long-term quest to study and protect endangered giant freshwater fish. These megafish, which include species like colossal catfish and gargantuan gars, are among the most endangered due to human impacts such as overfishing, dam building, and climate change. Conservation efforts are gaining momentum, with some species like the arapaima and alligator gar showing signs of recovery. In Cambodia, the Wonders of the Mekong project is raising awareness and working with local fishers to protect these species. The Cambodian government has also proposed turning a biodiverse stretch of the Mekong River into a UNESCO World Heritage site, offering hope for the future of these giant fish.

The construction of the Sekong A dam in Laos, led by the Vietnamese state-owned company Song Da 6, poses significant environmental risks to the Mekong River system, threatening biodiversity and local livelihoods. Despite its minimal energy output, the dam has geopolitical implications, with Vietnam seeking to counter China's influence in the region. Critics argue that the dam's energy could be replaced by more sustainable alternatives like solar power. The Mekong River Commission's upcoming transboundary environmental impact assessment offers a glimmer of hope for halting the project.

Fish biologist Zeb Hogan's quest to study and protect giant freshwater fish led to the discovery of a 661-pound stingray in Cambodia's Mekong River, marking a milestone in understanding these endangered species. Freshwater megafish populations have declined by 94 percent due to human impacts like overfishing, dam building, and climate change. Conservation efforts are emerging, such as the Wonders of the Mekong project, which works with local fishers to protect threatened species. Recent successes include the release of a large Mekong catfish by local fishers and the reintroduction of rare giant catfish and barb into the Mekong. The Cambodian government has proposed turning a biodiverse stretch of the river into a UNESCO World Heritage site, offering hope for these creatures' survival.

Fish biologist Zeb Hogan has been on a quest to study and protect giant freshwater fish, which are among the most endangered animals. In 2022, a giant freshwater stingray weighing 661 pounds was caught in the Mekong River, marking a milestone in Hogan's research. Hogan co-authored a book, 'Chasing Giants,' detailing the plight of megafish, which have declined by 94% due to human impacts. Conservation efforts are increasing, with some species like the arapaima and alligator gar showing signs of recovery due to stricter regulations and science-driven management. The Wonders of the Mekong project, led by Hogan and supported by the U.S. Agency for International Development, is working to raise awareness and protect these species in Cambodia. Recent conservation successes include the release of a giant catfish by local fishers and the Cambodian government's proposal to make a biodiverse stretch of the Mekong River a UNESCO World Heritage site.

In 2005, a Thai fisherman caught a record-breaking giant catfish in the Mekong, prompting biologist Zeb Hogan to investigate the world's largest freshwater fish. Hogan, with support from the World Wildlife Fund and National Geographic Society, launched the Megafish Project to study and protect these species. Despite their global distribution, many giant freshwater fish species are understudied and face threats from overfishing, dams, and pollution. Hogan's work includes hosting a TV show, 'Monster Fish,' and advocating for conservation efforts. Positive developments include countries committing to clean rivers, the establishment of protected areas, and local communities leading conservation efforts. The article also highlights the resilience of the Mekong's fish populations and ongoing research projects, such as 'Wonders of the Mekong,' funded by the US government.

The Vjosa River in southern Albania has been designated as a 'wild river national park,' a unique status that protects it from threats like dams and mining. This initiative, led by the international coalition Save the Blue Heart of Europe and supported by Patagonia, aims to preserve the river's ecological integrity. The park includes over 250 miles of waterways and adjacent land, housing more than 1,100 species. The success of the Vjosa campaign is inspiring similar conservation efforts in the Balkans and potentially worldwide, with rivers like the Una and Morača being considered for future protection. The designation is seen as a model for river conservation, emphasizing the need for a river-focused approach rather than traditional land protections.