Monodon monoceros Linnaeus, 1756 English: Narwhal German: Narwal Spanish: Narval French: Narval Family: Monodontidae 1. Description Narwhals are completely mottled on the back with white ventral and lateral fields
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چکیده
Narwhals are completely mottled on the back with white ventral and lateral fields that increase with age. Old males only maintain a narrow dark spotted pattern on the top of the back, whereas the rest of the body is white. Newborns are grey to brownish and develop the mottled pattern after 2 years. The rear margin of the tail flukes is markedly convex and the fin is replaced by a low ridge. Average Body length is 400 cm and 450 cm in adult males and females, respectively, and mass reaches 1000 kg and 1600 kg, respectively (HeideJørgensen, 2009).
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Highly Directional Sonar Beam of Narwhals (Monodon monoceros) Measured with a Vertical 16 Hydrophone Array
Recordings of narwhal (Monodon monoceros) echolocation signals were made using a linear 16 hydrophone array in the pack ice of Baffin Bay, West Greenland in 2013 at eleven sites. An average -3 dB beam width of 5.0° makes the narwhal click the most directional biosonar signal reported for any species to date. The beam shows a dorsal-ventral asymmetry with a narrower beam above the beam axis. Thi...
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