“We discovered that Hawaiian monk seals—one of the world’s most endangered marine mammals—are far more vocal underwater than previously known.”
Scientists previously thought monk seals had only six vocalizations based on observations of captive animals. After analyzing over 4,500 hours of underwater recordings across five habitats, University of Hawaii researchers found 25 distinct call types, including 20 never before documented. They also discovered seals combining calls together, a communication strategy never reported in any pinniped species. The findings matter because these low-frequency calls overlap with boat engine noise.