Related by context. Frequent words. (Click for all words.) 71 hydrophones 51 radio transmitters 50 sonar 49 transmitters 48 longlines 47 seismometers 46 sonars 46 microphones 45 transmitter 45 buoys 45 seismographs 45 infrasound 44 seismometer 44 vocalizations 44 porpoises 43 foghorn 42 dolphins 42 dorsal fins 41 earphones 41 Microphones 41 whale 41 whales 41 ear bud 41 baited hooks 41 echolocation 40 Transmitters 40 emergency beacons 40 kilohertz 40 electrodes 40 beaked whales 40 VHF radio 40 infrared camera 40 headphones 40 orcas 40 antennae 40 headsets 40 strobe light 40 marine biologists 39 beeps 39 infrared cameras 39 cetaceans 39 AUVs 39 underwater robot 39 cetacean 39 earpiece 39 humpback whale 39 optical telescopes 39 auditory nerve 39 infra red 39 distress beacon 39 beep 39 radios 39 beeping 39 marine mammals 39 earpieces 39 sperm whales 39 ultrasonic 38 hearing aids 38 detectors 38 satellites orbiting 38 marine mammal 38 webcams 38 autonomous underwater 38 sensors 38 beached whales 38 telemetry 37 earbuds 37 decoys 37 orbiting satellites 37 earbud 37 elephant seals 37 brainwaves 37 sirens 37 VHF 37 locator beacon 37 narwhal 37 pods 37 sea gulls 37 underwater robots 37 Detectors 37 scan sonar 37 telescopes 37 EPIRB 37 calliope 37 Jodrell Bank 37 vocalization 37 humpbacks 37 headset 37 Global Positioning System 37 geostationary satellites 36 audiologists 36 Geiger counters 36 squid 36 sea lions 36 motion detector 36 stethoscope 36 offshore wind turbines 36 radio transmissions 36 ambient noise 36 basking shark 36 oceanographers