Sonar is a technique that uses sound propagation to navigate, measure distances (ranging), communicate with or detect objects on or under the surface of the water, such as other vessels.
The Strait of Juan de Fuca is a body of water about 96 miles long that is the Salish Sea's main outlet to the Pacific Ocean. The international boundary between Canada and the United States runs down the centre of the Strait.
A hydrophone is a microphone designed for underwater use, for recording or listening to underwater sound. Most hydrophones contains a piezoelectric transducer that generates an electric potential when subjected to a pressure change, such as a sound wave.
The Strait of Georgia or the Georgia Strait is an arm of the Salish Sea between Vancouver Island and the extreme southwestern mainland coast of British Columbia, Canada, and the extreme northwestern mainland coast of Washington, United States. It is approximately 240 kilometres (150 mi) long and varies in width from 20 to 58 kilometres. Along with the Strait of Juan de Fuca and Puget Sound, it is a constituent part of the Salish Sea.
Reflection seismology is a method of exploration geophysics that uses the principles of seismology to estimate the properties of the Earth's subsurface from reflected seismic waves. The method requires a controlled seismic source of energy, such as dynamite or Tovex blast, a specialized air gun or a seismic vibrator. Reflection seismology is similar to sonar and echolocation.
The SOFAR channel, or deep sound channel (DSC), is a horizontal layer of water in the ocean at which depth the speed of sound is at its minimum. The SOFAR channel acts as a waveguide for sound, and low frequency sound waves within the channel may travel thousands of miles before dissipating. An example was reception of coded signals generated by the US Navy-chartered ocean surveillance vessel Cory Chouest off Heard Island, located in the southern Indian Ocean, by hydrophones in portions of all five major ocean basins and as distant as the North Atlantic and North Pacific.
Bloop was an ultra-low-frequency, high amplitude underwater sound detected by the U.S. National Oceanic and Atmospheric Administration (NOAA) in 1997. By 2012, earlier speculation that the sound originated from a marine animal was replaced by NOAA's description of the sound as being consistent with noises generated via non-tectonic cryoseisms originating from glacial movements such as ice calving, or through seabed gouging by ice.
A marine mammal observer (MMO) is a professional in environmental consulting who specializes in whales and dolphins.
The Salish Sea is a marginal sea of the Pacific Ocean located in the Canadian province of British Columbia and the U.S. state of Washington. It includes the Strait of Georgia, the Strait of Juan de Fuca, Puget Sound, and an intricate network of connecting channels and adjoining waterways.
Underwater acoustics is the study of the propagation of sound in water and the interaction of the mechanical waves that constitute sound with the water, its contents and its boundaries. The water may be in the ocean, a lake, a river or a tank. Typical frequencies associated with underwater acoustics are between 10 Hz and 1 MHz. The propagation of sound in the ocean at frequencies lower than 10 Hz is usually not possible without penetrating deep into the seabed, whereas frequencies above 1 MHz are rarely used because they are absorbed very quickly.
An autonomous recording unit (ARU) is a self-contained audio recording device that is deployed in marine or terrestrial environments for bioacoustical monitoring. The unit is used in both marine and terrestrial environments to track the behavior of animals and monitor their ecosystems. On a terrestrial level, the ARU can detect noises coming from bird habitats and determine relative emotions that each bird conveys along with the population of the birds and the relative vulnerability of the ecosystem. The ARU can also be used to understand noises made by marine life to see how the animals' communication affects the operation of their ecosystem. When underwater, the ARU can track the sound that human made machines make and see the effect those sounds have on marine life ecosystems. Up to 44 work days can be saved through the utilization of ARU's, along with their ability to discover more species.
RV Song of the Whale is a research vessel owned by Marine Conservation Research International and operated by Marine Conservation Research Ltd. The 70-foot vessel was designed specifically to carry out research on cetaceans using benign research techniques such as passive acoustic monitoring.
Ocean Networks Canada is a world-leading research and ocean observing facility hosted and owned by the University of Victoria, and managed by the not-for profit ONC Society. ONC operates unparalleled observatories in the deep ocean and coastal waters of Canada’s three coasts–the Arctic, the Pacific and the Atlantic–gathering biological, chemical, geological and physical data to drive solutions for science, industry and society. ONC operates the NEPTUNE and VENUS cabled ocean observatories in the northeast Pacific Ocean and the Salish Sea. Additionally, Ocean Networks Canada operates smaller community-based observatories offshore from Cambridge Bay, Nunavut., Campbell River, Kitamaat Village and Digby Island. These observatories collect data on physical, chemical, biological, and geological aspects of the ocean over long time periods. As with other ocean observatories such as ESONET, Ocean Observatories Initiative, MACHO and DONET, scientific instruments connected to Ocean Networks Canada are operated remotely and provide continuous streams of freely available data to researchers and the public. Over 200 gigabytes of data are collected every day.
The Whale Museum is a natural history museum located in Friday Harbor, Washington. Founded in 1979, The Whale Museum is dedicated to the interpretation of whales in the wild. Its mission is to promote the stewardship of wild whales in the Salish Sea ecosystem through education and research programs.
Christine Erbe is a German-Australian physicist specializing in underwater acoustics. She is a professor in the School of Earth and Planetary Sciences and director of the Centre for Marine Science and Technology (CMST)—both at Curtin University in Perth, Western Australia. Erbe is known for her research on acoustic masking in marine mammals, investigating how man-made underwater noise interferes with animal acoustic communication.
Jennifer Miksis-Olds is an American marine scientist known for her research using acoustics to track marine mammals.
The waters of the Salish Sea, on the west coast of North America, are home to several ecologically distinct populations of orcas. The area supports three major ecotypes of orcas: northern residents, southern residents, and transients. A fourth ecotype, the offshore orcas, occasionally venture into nearshore waters. Little to no interaction occurs between the different ecotypes. Resident and transient orcas have not been observed interbreeding, although occasional brief interactions occur.
The marine mammals of the Salish Sea are numerous and diverse, both in taxonomy and morphology. A total of six species of pinnipeds, eight species of baleen whales, seventeen species of toothed whales, and one mustelid inhabiting the local waters of the Salish Sea and the outer coastal waters over the continental shelf off Washington and British Columbia. The Salish Sea's ecosystem is characterized by cold, upwelling-drenched waters that provide nourishment for huge quantities of fish and crustaceans, the primary food of marine mammals, and as such, the diversity and abundance of marine mammals in the area are among the highest in the world.
