ON  THE  EVALUATION  OF  THE  CREST  FACTOR  OF  BIONIC  SIGNALS  USED  IN  HYDROACOUSTIC   COMMUNICATION  SYSTEMS

In this article, the authors evaluated the crest factor of bionic signals used in hydroacoustic communication systems, using the example of the study of signals based on the use of recordings of sounds of various whale species. The calculations and literature analysis show that the sound recordings of the following whale species have an acceptable crest factor value (p ≤ 4): Blue whale, Alaska humpback whale, Atlantic blue whale and Northeast Pacific blue whale. Recordings of the sounds of these types of whales should be used in the appropriate hydroacoustic communication systems. In contrast, recordings of the sounds of such whale species as Atlantic fin whale, Atlantic minke whale, South Pacific blue whale, and Western Pacific blue whale have an increased crest factor value (p > 4) and without adaptation, it is impractical to use them in appropriate hydroacousticcommunication systems. It is established that bionic signals used in hydroacoustic communication systems, based on the example of the study of signals based on the use of recordings of sounds of various species of whales, can have both an acceptable value of the crest factor or an increased one. It is advisable to pay attention of the de-velopers and manufacturers of the corresponding hydroacoustic communication systems to this conclusion during designing, testing and implementation of such systems.

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A NEW HYBRID BETWEEN A BLUE WHALE, BALAENOPTERA MUSCULUS, AND A FIN WHALE, B. PHYSALUS: FREQUENCY AND IMPLICATIONS OF HYBRIDIZATION

Marine Mammal Science ◽

10.1111/j.1748-7692.1998.tb00692.x ◽

1998 ◽

Vol 14 (1) ◽

pp. 82-98 ◽

Cited By ~ 50

Author(s):

Martine Berube ◽

Alex Aguilar

Keyword(s):

Balaenoptera Musculus ◽

Blue Whale ◽

Fin Whale

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Cetacean records along a coastal-offshore gradient in the Vitória-Trindade Chain, western South Atlantic Ocean

Brazilian Journal of Biology ◽

10.1590/1519-6984.21812 ◽

2014 ◽

Vol 74 (1) ◽

pp. 137-144 ◽

Cited By ~ 16

Author(s):

LL Wedekin ◽

MR Rossi-Santos ◽

C Baracho ◽

AL Cypriano-Souza ◽

PC Simões-Lopes

Keyword(s):

Humpback Whale ◽

South Atlantic ◽

Breeding Habitat ◽

Humpback Whales ◽

Balaenoptera Physalus ◽

Fin Whale ◽

Antarctic Minke Whale ◽

Trindade Island ◽

The Antarctic ◽

Species Being

Oceanic waters are difficult to assess, and there are many gaps in knowledge regarding cetacean occurrence. To fill some of these gaps, this article provides important cetacean records obtained in the winter of 2010 during a dedicated expedition to collect visual and acoustic information in the Vitória-Trindade seamounts. We observed 19 groups of cetaceans along a 1300-km search trajectory, with six species being identified: the humpback whale (Megaptera novaeangliae, N = 9 groups), the fin whale (Balaenoptera physalus, N = 1), the Antarctic minke whale (Balaenoptera bonaerensis, N = 1), the rough-toothed dolphin (Steno bredanensis, N = 1), the bottlenose dolphin (Tursiops truncatus, N = 2), and the killer whale (Orcinus orca, N = 1). Most humpback whale groups (N = 7; 78%) were observed in the Vitória-Trindade seamounts, especially the mounts close to the Abrolhos Bank. Only one lone humpback whale was observed near Trindade Island after a search effort encompassing more than 520 km. From a total of 28 acoustic stations, humpback whale songs were only detected near the seamounts close to the Abrolhos Bank, where most groups of this species were visually detected (including a competitive group and groups with calves). The presence of humpback whales at the Trindade Island and surroundings is most likely occasional, with few sightings and low density. Finally, we observed a significant number of humpback whales along the seamounts close to the Abrolhos Bank, which may function as a breeding habitat for this species. We also added important records regarding the occurrence of cetaceans in these mounts and in the Western South Atlantic, including the endangered fin whale.

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Fin whale tracks recorded by a seismic network on the Juan de Fuca Ridge, Northeast Pacific Ocean

The Journal of the Acoustical Society of America ◽

10.1121/1.4774275 ◽

2013 ◽

Vol 133 (3) ◽

pp. 1751-1761 ◽

Cited By ~ 19

Author(s):

Dax C. Soule ◽

William S. D. Wilcock

Keyword(s):

Pacific Ocean ◽

Seismic Network ◽

Juan De Fuca Ridge ◽

Fin Whale ◽

Fuca Ridge ◽

Northeast Pacific ◽

Juan De Fuca ◽

Northeast Pacific Ocean

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Great Whales

10.1071/9780643096196 ◽

2008 ◽

Cited By ~ 6

Author(s):

John Bannister

Keyword(s):

Sperm Whale ◽

Modern Technology ◽

Current Status ◽

Blue Whale ◽

Baleen Whales ◽

Fin Whale ◽

Right Whale ◽

Toothed Whale ◽

History Of ◽

Storey Building

Whales are mysterious and fascinating creatures. Despite modern technology, their world is still largely unexplored and unknown. They can only be seen, or rather glimpsed, when they are near the sea surface, either from boats, or perhaps from shore, or underwater by divers. They also reach astonishing sizes – the blue whale, for example, can grow to 30 metres in length, equivalent to the height of a six-storey building, and can weigh more than 130 tonnes. Seven ‘Great Whales’ are found in the coastal waters surrounding Australia. These include six of the largest baleen whales – blue whale, fin whale, humpback whale, sei whale, Bryde’s whale and southern right whale – and the sperm whale, the largest toothed whale. This book provides a detailed account of these extraordinary mammals. As well as the seven Great Whales, a smaller species – the minke whale – is included because of its special interest to Australians. The book describes whales’ highly specialised mammalian structure and biology, and the history of people’s association with them, at first through legend and wonder, then whaling, and more recently whale watching. It also looks at their past and current status, and the conservation initiatives that are in place to protect them from existing or potential threats. With both historical and recent photographs, as well as an extensive glossary, Great Whales will be enjoyed by natural history enthusiasts, zoologists and students alike.

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