A human-sized shark and a school of smaller sharks were observed swimming near a diver off the coast of Jeju Island, South Korea [1].

The encounter highlights a growing trend of large marine predators appearing in regional waters. Experts said rising sea temperatures driven by climate change are shifting fish distributions, which leads to more frequent sightings of large sharks in Korean waters [1].

Park Shin-hye, a haenyeo diver, described the experience of seeing a shark roughly the size of a human body accompanied by a group of smaller sharks [1]. She said the sharks circled around her in a ring before swimming away, and she was surprised by the encounter [1].

Some of the large sharks observed in the area are estimated to be between two and three meters in length [2]. These animals are believed to belong to the bigeye thresher shark family [1].

The presence of these predators is becoming a documented pattern in the region. The Coast Guard in Jeju has confirmed 14 shark sightings in these waters over the past three years [1].

While these sightings are increasing, the sharks in this specific encounter did not attack the diver. However, the shift in migration patterns suggests that the local marine ecosystem is reacting to broader environmental changes occurring across the Pacific.

“A human-sized shark and a school of smaller sharks were observed swimming near a diver”

The increasing frequency of large shark sightings in Jeju waters serves as a biological indicator of ocean warming. As climate change alters water temperatures, species typically found in warmer or deeper currents are migrating into new territories. This shift not only changes the local biodiversity but also increases the likelihood of interactions between humans and large marine predators in areas where such encounters were previously rare.