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

Range-dependent flexibility in the acoustic field of view of echolocating porpoises (Phocoena phocoena)

Toothed whales use sonar to detect, locate, and track prey. They adjust emitted sound intensity, auditory sensitivity and click rate to target range, and terminate prey pursuits with high-repetition-rate, low-intensity buzzes. However, their narrow acoustic field of view (FOV) is considered stable throughout target approach, which could facilitate prey escape at close-range. Here, we show that,...

Acoustic evidence that harbor porpoises (Phocoena phocoena) avoid bottlenose dolphins (Tursiops truncatus)

EIREN K. JACOBSON, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0208, U.S.A.; KARIN A. FORNEY, Marine Mammal and Turtle Divison, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 110 Shaffer Road, Santa Cruz, California 95060, U.S.A.; JAMES T. HARVEY, ...

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

Single source sound production and dynamic beam formation in echolocating harbour porpoises (Phocoena phocoena).

Echolocating toothed whales produce high-powered clicks by pneumatic actuation of phonic lips in their nasal complexes. All non-physeteroid toothed whales have two pairs of phonic lips allowing many of these species to produce both whistles and clicks at the same time. That has led to the hypothesis that toothed whales can increase the power outputs and bandwidths of clicks, and enable fast cli...

Histological investigations on the thyroid glands of marine mammals (Phoca vitulina, Phocoena phocoena) and the possible implications of marine pollution.

In 1988 and 1989, thousands of harbor seals (Phoca vitulina) died in the North Sea from phocine distemper infection. The morphology of thyroid glands from 40 harbor seals found dead on the North Sea coastlines of Schleswig-Holstein, Federal Republic of Germany, during an epizootic of phocine distemper, was compared with the morphology of thyroid glands from five healthy harbor seals collected i...