When the first frozen remains of these ancient creatures were discovered on Sol-3, early paleontologists had little infomation to go on and made countless errors. Once thought clumsy and slow-moving, the species is now known to have been quite agile despite their hefty bulk.
I'd be scared shitless. But I dont think they are silent. They making grunting noises and you can hear their fat flaps jiggle. It lets you know they're coming.