Purnima- Pic- FinalWhen it comes to mon­i­toring the abun­dance and behav­iors of whales, most research and con­ser­va­tion efforts rely on visual obser­va­tions. People go out on a boat and sys­tem­at­i­cally scan the ocean, clip­board in hand. “But the ocean is very vast, and it takes time to do this kind of survey,” said Purnima Ratilal, asso­ciate pro­fessor in the Depart­ment of Elec­trical and Com­puter Engi­neering at Northeastern.