The “International Day of the Baltic Harbour Porpoise” is celebrated on the third Sunday in May of each year, to raise awareness of the alarming situation of the harbour porpoise, a rather unique marine mammal. And indeed: it is the only cetacean that calls the Baltic Sea its permanent home.
In the Baltic Sea region, harbour porpoises (Phocoena phocoena) were actively hunted until the end of the 19th century. Although this practice has stopped, their populations declined rapidly since the middle of the 20th century. They are now heavily impacted by other human pressures, most notably by-catch in fishing gear, but also pollutants, habitat deterioration and disturbance caused by underwater noise.
The “International Day of the Baltic Harbour Porpoise” (IDBHP) was declared an international observance by the Agreement on the Conservation of Small Cetaceans in the Baltic, North East Atlantic, Irish and North Seas (UNEP/ASCOBANS).