Scientists offer explanation for Jesus’ ‘miraculous catch of fish’
Analysis of rare mass fish mortality events in Sea of Galilee reveals that strong winds cause lower, oxygen-poor water levels to rise, suffocating fish and bringing them to surface
Sue Surkes is The Times of Israel's environment reporter
Israeli researchers have posited a possible scientific explanation for the Christian “miraculous catch of fish” — two separate accounts set in northern Israel’s Sea of Galilee, in which Jesus turned unsuccessful attempts to catch fish into massive hauls.
The research, published in Water Resources Research last week, points to incidences of strong winds that triggered internal waves. These waves caused low-oxygen water from deeper layers of the lake to rise up, probably suffocating the fish to death.
The fish floated to the surface, becoming accessible to fishermen.
Mass fish mortality has been reported once in the 1990s and in 2007, 2012, and 2023, according to Dr. Tamar Zohary, a researcher from the Kinneret Limnological Laboratory, part of the Israel Oceanographic and Limnological Research institute, which teamed up with the Agriculture Ministry’s Volcani Institute, and Griffith University, Australia, for the research.
Last year’s incident in the Tzalmon estuary of the Sea of Galilee initially triggered suspicions of poisoning.
Sensors installed in the lake in 2003 have been tracking temperatures in the water column and the direction and speed of the winds.
The team reached its conclusion after using the data to create a 3D model of the lake and the atmosphere during the fish kill events.
“The Sea of Galilee is a stratified lake. The upper layer is warm and oxygenated, while the lower layer is cold and lacks oxygen,” Yael Amitai, a physical limnologist from the Kinneret laboratory, explained.
“When a strong westerly wind blows, it pushes the upper warmer layer of water from the lake’s west to the east, where it piles up, pressing on the existing water. In the west of the lake, water from the lower layer rises. In this way, fluctuations called internal waves are created in the water profile.”
Ehud Strobach, a climate researcher from the Volcani Institute, has demonstrated the phenomenon using a dynamic lake model coupled with an atmospheric model.
“Using observations from the monitoring program in the Sea of Galilee, we created short 3D lake simulations for two fish kill events,” he said. “These simulations indicate the initiation of internal waves and upwelling of cold anoxic (oxygen-poor) water into the surface at the location and time of the fish kill events.”
The study highlights the rarity of these events, which occur under specific environmental conditions.
According to the researchers, understanding these conditions can help predict and potentially mitigate future fish kills in the Sea of Galilee and other similar water bodies.
The Israel Water Authority partly funded the study.
