Climate change alters distribution of sea life

The Korea Institute of Ocean Science and Technology (KIOST, President Hyi Seung Lee) established, through genetic connectivity analysis, that a northward shift in the habitat of Turbo sazae, from the southern coast to the eastern coast of Korea, is closely related to rising sea temperatures caused by climate change. The research findings were published in an international academic journal.*

* Title of publication: Insights into the Genetic Connectivity and Climate-Driven Northward Range Expansion of Turbo sazae (Gastropoda: Turbinidae) Along the Eastern Coast of Korea. Hyun-sung Yang, Kyung-man Kwon & Hyun-soo Roh, KIOST; Young-Ghan Cho et al., NIFS. Animals, May 2, 2025.

According to the National Comprehensive Investigation into Marine Ecosystems conducted by the Korea Marine Environment Management Corporation, T. sazae, which had primarily inhabited the southern coast of Korea, were found to have expanded their habitat 37 degrees north (near Uljin) as of 2018. This suggests that climate change-driven rises in sea temperatures are gradually expanding northward the inhabitable environment for sea life, which a research team at KIOST verified through genetic connectivity analysis.

A team of researchers led by Dr. Hyun-sung Yang of the Tropical and Subtropical Research Center at KIOST and another research team led by Dr. Young-Ghan Cho of the Tidal Flat Research Institute at the National Institute of Fisheries Science collaborated on the study, which predicted the impact of barren ground* caused by climate change on marine benthic life and analyzed the physiological, ecological, and genetic characteristics of T. sazae accordingly. They found that the T. sazae found around Jeju Island and on the eastern coast were varieties with identical genetic characteristics.

* The phenomenon in which kelp disappears from coastal rocky areas to be replaced by white calcareous algae, leaving the affected areas white. An element of marine desertification.

In addition, a research team at the Jeju Bio Research Center at KIOST found the main cause of an observed decline in T. sazae population to be a decrease in immune function caused by rising sea temperatures. Previously, it had been speculated that urchin barrens changed the feeding patterns of T. sazae living around Jeju Island, causing the decline in their population, but the research findings* indicate that the changed feeding patterns do not impact T. sazae’s reproduction or physiology, and that the real cause is compromised immune function of the mollusk as a result of warmer waters.

* Title of publication: Effect of Diet Changes in Benthic Ecosystems Owing to Climate Change on the Physiological Responses of Turbo sazae in Waters Around Jeju Island, Korea. Yong-kyun Ryu, Chulhong Oh, Hyun-sung Yang, KIOST. Marine Environmental Research, Feb. 6, 2025.

The findings are scientific evidence that T. sazae larvae likely move northward along ocean currents such as the Tsushima Current to settle on the eastern coast, resulting in an expansion of their habitat. These findings are also a significant achievement in that they clarify some of the impacts of climate change on the distribution of sea life through a comprehensive analysis of the morphological features and genetic information of the T. sazae populations around Jeju Island and along the eastern coast.

In particular, the fact that rising sea temperatures allow the northward expansion of T. sazae’s habitat is expected to be key information in understanding climate-adaptive mechanisms of sea life as well as in forming climate change response strategies.

KIOST President Hyi Seung Lee explained, “Climate change-driven rises in sea temperatures are a core variable in the impact of climate change on marine ecosystems.” He went on to say, “KIOST will use its latest research findings to gain a scientific understanding of patterns of change in the distribution of sea life and continue the scientific mission to protect sea life.”

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.