15 July, 2025

Martha Henriques The world's smallest sea is suffering from an unusual blight: marine mucilage, more commonly known as "sea snot". Each year, pollution and warming waters in Turkey's Marmara Sea boost the growth of tiny organisms called phytoplankton. These organisms coat fish larvae, eggs, mussels, corals and other living things in a thick layer of slime. Katie Nadworny reports on how Istanbul is scrambling to stem the sea pollution. Plus: you think you know the dodo? Think again.

CLIMATE CONVERSATION Saving a sea smothered in 'snot' The Marmara Sea is plagued with "snot", which throttles life below the waves. Credit: Tahsin Ceylan For much of the year, life on the Turkish island of Burgazada is a peaceful experience, accompanied by the sound of chirping birds and the waves of the Marmara Sea lapping at the shore. ‌ But come the warmer months, the tiny Marmara Sea becomes choked with a plague of marine mucilage, coating living things in a thick layer of slime. The problem is visible from the surface, but below the waves the strings of "sea snot" are even more dense. ‌ Caused by a combination of factors, including rising temperatures, pollution and the local geography, sea snot is an ever-growing problem in the Marmara Sea as waters warm with climate change. Officials have put together a plan to reduce the pollution running into the sea which fuels the growth of mucilage, but locals have yet to see many results. ‌ Read about the Marmara Sea's struggles and the measures that could revive it by clicking the button below. See the slimy sea

THE BIG PICTURE The lonely puma with a lasting legacy P-22 was LA's best-known puma, and became the face of the campaign for the world's largest wildlife bridge. Credit: Steve Winter In a city brimming with celebrities, only one has led to the creation of what will be the world's largest wildlife crossing. The puma, or mountain lion, known as P-22 was a charismatic male who came to live in a Los Angeles park just outside Hollywood. P-22 was cut off from any potential mates by the eight lanes of the 101 Freeway, sparking a campaign to build a huge bridge for animals. Click the button below to read about P-22's legacy.  Meet the 'Brad Pitt' of pumas

CLIMATE QUIZ Which breed of dog is especially hard to protect from extreme heat? A. German shepherd B. Labrador C. Bulldog Scroll to the bottom of this newsletter for the answer.

MORE CLIMATE FROM THE BBC China's carbon emissions may be falling  As the world races to cut climate-warming emissions, a potentially game-changing milestone may have been reached.   Keep reading >‌ Tiny animals gorge, get fat and fight global warming An obscure creature often sold as aquarium food has been quietly slowing our planet's heating, scientists have found.   Keep reading >‌ Mediterranean Sea up to 7C above normal It has been the western Mediterranean's most extreme heatwave for the time of year, with areas 7C (13F) hotter than usual.   Keep reading >‌