In wave physics and engineering, directional emission sets a fundamental limitation on conventional simple sources as their sizes should be sufficiently larger than their wavelength. Artificial metamaterial and animal biosonar…
Algorithms are presented for the accurate time of arrival difference estimation of high frequency narrow band echolocation clicks from Harbor Porpoise. These clicks typically have a center frequency of around…
Unlike the large number of species of true dolphins, there are only seven porpoise or phocoenid species, inhabiting different habitats and climate zones. They range from ice-covered water in the…
Studies on odontocetes (e.g., porpoises) have revealed that these animals may adaptively use vision. The present study examined the contributions of vision to the approaching behavior of the harbor porpoise…
Cetaceans use sound for communication, navigation and finding prey. Most extant odontocetes produce broadband (BB) biosonar clicks covering frequency ranges from tens of kilohertz to 150–170 kHz. In contrast, the…
Social delphinids employ a vocal repertoire of clicks for echolocation and whistles for communication. Conversely, the less social and acoustically cryptic harbour porpoises (Phocoena phocoena) only produce narrow-band high-frequency (NBHF)…
Marine renewable energy (MRE) developments often coincide with sites frequented by small cetaceans. To understand habitat use and assess potential impact from development, echolocation clicks were recorded with acoustic click…
Harbor porpoises (Phocoena phocoena) use narrow band echolocation signals for detecting and locating prey and for spatial orientation. In this study, acoustic impedance values of tissues in the porpoise's head…
Porpoises are small-toothed whales, and they can produce directional acoustic waves to detect and track prey with high resolution and a wide field of view. Their sound-source sizes are rather…
The mechanism by which odontocetes produce sound is unique among mammals. To gain insight into the physiological properties that support sound production in toothed whales, we examined myoglobin content ([Mb]),…