Thousands of Fish Die in Bali's Batur Lake Caused by Limnology and Natural Hydrothermal

DENPASAR - The Geological Agency, Ministry of Energy and Mineral Resources (ESDM) revealed that the phenomenon of thousands of fish suddenly dying in Lake Batur, Bangli Regency, Bali, was triggered by natural limnological and hydrothermal dynamics.

"This is not an indication of an eruption at Mount Batur," said Acting Head of the Geological Agency of the Ministry of Energy and Mineral Resources, Lana Saria, as reported by ANTARA, Friday, July 24.

Limnology is a science about terrestrial aquatic ecosystems whose studies reveal the structure and function of the relationship between terrestrial aquatic organisms and their relationship with the physical, chemical and biological dynamics of the environment.

Based on the analysis of the Geological Agency, the phenomenon of the emergence of gas explosions in the largest lake on the Island of the Gods is related to the natural dynamics that occur within the caldera of Mount Batur.

He explained that under certain conditions, especially when there is a mixing of water masses (overturn / upwelling), water from the bottom layer of the lake which is low in oxygen and contains dissolved gases, such as hydrogen sulfide (H2S), can be lifted to the surface.

The release of gas, he added, can cause a sulfur smell and a decrease in dissolved oxygen levels in the waters potentially causing mass fish deaths.

Meanwhile, regarding volcanic activity at the volcano which is 1,717 meters above sea level, Lana added that there was no indication of an increase in volcanic tremors.

"The level of activity of Mount Batur is still at level I or normal with the recommendation that tourists or the community do not have activities in the crater of Mount Batur," he added.

Previously, since the beginning of this week, thousands of Nile tilapia fish, including those cultivated by farmers, have died en masse.

Until now, the Bangli Regency Government through the Bangli Regency Food and Fisheries Directorate (KPP) is calculating the estimated number of dead fish.

"For the number of dead fish, we have not released it because the sulfur eruption has not stopped yet," said Head of the Bangli KPP Office Wayan Sarma.