Phocoenoides dalli True 1885
7. Dall’s Porpoise Phocoenoides dalli French: Marsouin de Dall / German: Weilflanken-Schweinswal / Spanish: Marsopa de Dall Other common names: Dall Porpoise, True Porpoise; Dalli-type Dall's Porpoise (dalli); Truei-type Dall’s Porpoise, True's Porpoise (true) Taxonomy. Phocaena dalli True...
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Format: | Other/Unknown Material |
Language: | unknown |
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Lynx Edicions
2014
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Online Access: | https://zenodo.org/record/6607558 https://doi.org/10.5281/zenodo.6607558 |
Summary: | 7. Dall’s Porpoise Phocoenoides dalli French: Marsouin de Dall / German: Weilflanken-Schweinswal / Spanish: Marsopa de Dall Other common names: Dall Porpoise, True Porpoise; Dalli-type Dall's Porpoise (dalli); Truei-type Dall’s Porpoise, True's Porpoise (true) Taxonomy. Phocaena dalli True, 1885, USA, Alaska, “in the strait west of Adakh [sic] Island, one of the Aleutian group.” Two subspecies are recognized. Subspecies and Distribution. P. d. dalli True, 1885 — cool temperate regions of the N Pacific Ocean from Japan to Alaska and S to N Baja California, Mexico. P d. truee Andrews, 1911 — NW Pacific ÚCCZUI waters ¢.35-534° N, including the Okhotsk Sea. Descriptive notes. Total length 165-240 cm; weight 60-200 kg. Dall’s Porpoise is the largest member of the family, reaching lengths of up to 240 cm for males and 220 cm for females. It is very stocky, with a very small head and small appendages. There is a very slight, poorly defined beak. Dorsal fin is wide-based and triangular, and in males,it is extremely canted forward. Tailstock is deepened, exceedingly in adult males. Flukes may have a convex trailing edge, especially in adult males. Color pattern is contrasting black and white, with a large, ventrally continuous, white flank patch (extending farther forward in the subspecies truei) and white frosting on upper margins of dorsal fin and trailing edge of flukes. In newborns, color pattern is muted, consisting of various shades of gray, and frosting on fin and flukes is absent. Color pattern becomes bolder as individuals age, and frosting (or trim) begins to appear in the first year of age. Tooth counts generally are 23-28 in each half of each jaw. Habitat. Deep, cold waters. Dall’s Porpoises are generally found far offshore, but they do occur in nearshore waters where there is water deeper than 100-200 m nearby. They are commonly seen in the inshore waters of north-western USA (Washington, Alaska) and west Canada (British Columbia), where they inhabit deep channels and passes. Food and Feeding. Dall’s ... |
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