The use of an air bubble curtain to reduce the received sound levels for harbor porpoises (Phocoena phocoena).

Bony Nares Air Pressure and Nasal Plug Muscle Activity during Click Production in the Harbour Porpoise, Phocoena Phocoena, and the Bottlenosed Dolphin, Tursiops Truncatus

Sound production mechanisms have been studied in two delphinid species the harbour porpoise, Phocoena phocoena (L.), and the bottlenosed dolphin, Tursiops truncatus (Montagu). It was found that, in both species, the click sound production was coupled to a considerable pressure increase in the bony nares. The maximum pressure recorded in Phocoena was approximately 54kPa and in Tursiops close to ...

Acoustic radiation from the head of echolocating harbor porpoises (Phocoena phocoena).

An experiment was conducted to investigate the sound pressure patterns on the melon of odontocetes by using four broadband hydrophones embedded in suction cups to measure echolocation signals on the surface of the forehead of two harbor porpoises (Phocoena phocoena). It has long been hypothesized that the special lipids found in the melon of odontocetes, and not in any other mammals, focus soun...

Temporary shift in masked hearing thresholds in a harbor porpoise (Phocoena phocoena) after exposure to seismic airgun stimuli.

An auditory study was conducted to derive data on temporary threshold shift (TTS) induced by single impulses. This information should serve as basis for the definition of noise exposure criteria for harbor porpoises. The measurements of TTS were conducted on a harbor porpoise by measuring the auditory evoked potentials in response to amplitude-modulated sounds. After obtaining baseline hearing ...

Functional morphology of the nasal complex in the harbor porpoise (Phocoena phocoena l.).

Toothed whales (Odontoceti, Cetacea) are the only aquatic mammals known to echolocate, and probably all of them are able to produce click sounds and to synthesize their echoes into a three-dimensional "acoustic image" of their environment. In contrast to other mammals, toothed whales generate their vocalizations (i.e., echolocation clicks) by a pneumatically-driven process in their nasal comple...

Arsenic speciation in bodily fluids of harbor seals (Phoca vitulina) and harbor porpoises (Phocoena phocoena)