A magnitude 7.8 earthquake that struck southern Mindanao in the Philippines on Monday caused the seabed to rise by up to two meters, resulting in significant damage to marine ecosystems, officials said Sunday. The tremor, centered near the Cotabato Trench, killed at least 61 people and left around 40 others missing, according to updated figures from the country’s disaster agency.

The Philippine Institute of Volcanology and Seismology reported that the seismic event triggered a phenomenon known as coastal uplift, which pushed parts of the coastline in Sarangani and Davao Occidental provinces upward, exposing areas of the seabed that were previously underwater. This change extended the shoreline by as much as 200 meters in certain locations.

Following the earthquake, local residents observed the exposed coral reefs and seagrass beds two days later, raising alarms about potential health hazards from gases emitted by decaying marine organisms. Environmental teams sent to survey the area confirmed that large stretches of reef and seagrass had become uncovered, causing widespread death among marine life, including reef fish, eels, clams, and shells.

Officials noted the difficulty in determining the full extent of the affected areas due to the size of the coastline involved. Photographs released by the environment department’s regional office depicted extensive coral exposure with numerous dead aquatic creatures scattered on the newly uncovered seabed.

The Cotabato Trench, situated approximately 50 kilometers off southern Mindanao’s coast, is known for its seismic activity, including a series of minor tremors earlier this year. The recent earthquake represents one of the more powerful events linked to the trench in recent history, underscoring ongoing geological risks in the region.

Authorities continue to assess the environmental impact as well as the human toll, while rescue and recovery operations proceed in the affected provinces. The damage to marine habitats may have long-term implications for local fisheries and coastal communities dependent on these ecosystems.