These strange formations may look like the results of a gigantic sneeze in the sea but experts fear they might be a dangerous sign the world’s oceans are warming.

The scientists in this video studying the ghastly looking ‘blobs’ think they are caused by sea creatures becoming stressed by changes to their surroundings.

Marine Science Director of Marche Polytechnic University Roberto Danovaro from Ancona, Italy, and his team have been studying the mucus clouds for 10 years and have noticed a dramatic rise along the Mediterranean coast line.

The sea bogeys — gatherings of sugar substances squirted out by phytoplanktons — could pose a danger for swimmers because they can trap harmful viruses and bacteria.