(IMAGE) Technical University of Munich (TUM) Caption Most of the world's mussel stocks are in decline and some species face extinction like the freshwater pearl mussel or so-called Margaritifera margaritifera. Credit (Photo: TUM/ Geist) Usage Restrictions To be used together with the press release of TUM License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.