Call of An Elephant Seal (AUDIO) Cell Press Your browser does not support the audio element. Caption This audio recording is a natural threat call of a northern elephant seal followed by four modified signals (pulse rate slowed down by 0.15 Hz and 1 Hz, centroid of the frequency spectrum shifted up by 50 and 200 Hz). Credit Mathevon et al. Usage Restrictions Credit required. 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.