Yesterday the Internet was shocked with the photos of thd yellow surface of the Baltic sea. Russian scientists know the reason and say it is nothing to worry about.

Researchers link this phenomenon with blooming of such plants like currant, rowan, hawthorn, wild rose. Pine trees are also an important source of pollen. During raining the pollen is washed out of flowers and concentrates on puddles' surface, and its major part stays on the sea surface, where becomes a vital protein source for little fish.

Researchers warn those, who are prone to allergy, to take care during the days of active blooming.