Global Warming Has Summoned the 'Deadly Poisonous' Blue-Ringed Octopus

Korean Peninsula Sea Temperature Rises Twice as Fast as Global Average
Changes in Fish Species and Catch Volume... Increased Appearance of Subtropical Species

Blue-ringed octopus. (Photo by National Institute of Fisheries Science)

[Asia Economy Reporter Yoon Seul-gi] The seas around the Korean Peninsula are heating up due to global warming. In Jeju, known as the frontline of climate change, the frequent discovery of subtropical species is becoming a common occurrence.

According to the Jeju Seogwipo Coast Guard Station, a blue-ringed octopus was found on the rocky shore of Soesokkak in Seogwipo City on the afternoon of the 13th. Although the blue-ringed octopus is small, about 10cm in size, it possesses a toxin called tetrodotoxin (TTX) in its jaws and teeth. This toxin is more than 10 times stronger than cyanide and is known to be lethal to humans with just 1mg.

If bitten or exposed to the toxin by touching it with bare hands, symptoms such as paralysis, vomiting, difficulty breathing, and cardiac arrest may occur. The mucus and ink also contain toxic substances, so caution is necessary when dealing with this creature.

The blue-ringed octopus mainly inhabits subtropical seas in the South Pacific, such as Australia, Indonesia, the Philippines, and Sri Lanka. Since its first discovery in 2012, sightings in domestic waters including Jeju have increased. Last year, there were a total of 11 sightings in Jeju, and it has also been occasionally spotted along the southern coast and southern East Sea areas such as Yeosu, Geoje, Gijang, Busan, and Ulsan.

The appearance of the subtropical blue-ringed octopus in the waters around the Korean Peninsula is an effect of global warming. According to the "National Marine Ecosystem Comprehensive Survey 3rd Cycle (2015?2020)" announced by the Ministry of Oceans and Fisheries last year, subtropicalization is progressing in the Jeju and southern coastal waters.

The survey results show that compared to temperate seaweed (brown algae such as seaweed and kelp), tropical-temperate mixed seaweed (red algae such as gim and umutgasari), which inhabit relatively warmer seas, have expanded in species number and distribution across all Korean waters except the western southern sea. Warm current fish species are also on the rise. An analysis of fish species (a total of 112 species) appearing in waters directly influenced by the warm Tsushima Current showed that the number of warm current species increased by about 18% over the past six years (52% in 2015 → 70% in 2020).

However, experts say it is still too early to conclude that the blue-ringed octopus has settled in Jeju. Go Jun-cheol, a researcher at the Jeju Fisheries Research Institute of the National Institute of Fisheries Science, said, "To determine that it has settled in Jeju waters, the population must be consistently confirmed, but that is not the case." He added, "While it is true that the frequency of sightings has increased due to rising sea temperatures in Jeju, the increase in citizen reports is also influenced by strengthened publicity about the dangers of the blue-ringed octopus, and there are signs that previously introduced blue-ringed octopuses are adapting to Jeju waters."

On the morning of the 19th, vacationers visiting Geumnung Beach in Hallim-eup, Jeju-si, are enjoying the summer atmosphere. [Image source=Yonhap News]

◆ The Heating Seas of the Korean Peninsula... Government Also Takes Action on Climate Change

According to the "Marine Climate Analysis Report" released by the Korea Meteorological Administration in January, the sea surface temperature and wave height around the Earth and the Korean Peninsula have continuously risen over the past 40 years from 1981 to 2020. The upward trend has been particularly noticeable since 2010.

The average surface water temperature near the Korean Peninsula (new normal value) is 18.53°C, which is 0.21°C higher than the average value (old normal value) of 18.32°C over the previous 30 years (1981?2010). Compared to the global average surface water temperature increase of 0.12°C (from 18.18°C to 18.30°C) during the same period, the rise around the Korean Peninsula is about twice as large.

The rise in sea temperature is also affecting marine ecosystems. Changes in catch species have caused significant damage to aquaculture. According to data submitted by the Ministry of Oceans and Fisheries to Shin Jeong-hoon, a member of the National Assembly’s Agriculture, Food, Rural Affairs, Oceans and Fisheries Committee from the Democratic Party, the damage to aquaculture caused by temperature changes and abnormal climate from 2012 to last year totaled 139.2 billion KRW, with 89% of the damage attributed to high water temperatures.

The government has taken measures to minimize losses caused by climate change. On the 15th, the Ministry of Oceans and Fisheries announced the 4th Comprehensive Plan for Climate Change Response in the Marine and Fisheries Sector (2022?2026), stating that major carbon emission sources such as shipping and ports will be converted to eco-friendly alternatives. The plan also includes a significant expansion of "blue carbon," which is gaining attention as a carbon sink.

This 4th plan concretely includes the 5-year implementation measures of the "2050 Carbon Neutral Roadmap for the Marine and Fisheries Sector," established last December. The Ministry of Oceans and Fisheries set policy goals to ▲reduce greenhouse gas emissions in the marine and fisheries sector by 70% by 2030 (compared to 2018), ▲minimize loss of life and property from coastal and marine climate disasters, and ▲enhance public awareness and experience of marine climate crisis response policies.

This content was produced with the assistance of AI translation services.