Elasmobranchii (sharks and rays) > Lamniformes
(Mackerel sharks) > Lamnidae
(Mackerel sharks or white shark)
Etymology: Lamna: Greek, lamna, -es = a shark (Ref. 45335); ditropis: Named comes from the greek 'di' meaning two and 'tropis' meaning keel (Ref. 6885). More on author: Hubbs.
Environment / Climate / Range
Marine; pelagic-oceanic; oceanodromous (Ref. 51243); depth range 0 - 650 m (Ref. 50550), usually 0 - 152 m (Ref. 55221). Temperate; 66°N - 22°N, 120°E - 115°W
Length at first maturity / Size / Weight / Age
Maturity: Lm ?, range 180 - 240 cm
Max length : 305 cm TL male/unsexed; (Ref. 247); common length : 180 cm TL male/unsexed; (Ref. 9988); max. published weight: 175.0 kg (Ref. 9988)
North Pacific: Japan, Korea, and the Sea of Okhotsk to the Bering Sea and southward to southern California, USA (Ref. 247) and Baja California, Mexico (Ref. 9253).
A coastal-littoral and epipelagic shark that prefers boreal to cool temperate waters, from the surface to at least 152 m (Ref. 247). Common in continental offshore waters but range inshore to just off beaches (Ref. 247). Occurs singly or in schools or feeding aggregations of several individuals (Ref. 247). Feeds on fishes (Ref. 247). Ovoviviparous, embryos feeding on yolk sac and other ova produced by the mother (Ref. 50449). With up to 4 young in a litter (Ref. 247). Fast swimmer (Ref. 9988). Potentially dangerous but has never or seldom been implicated in human attacks (Ref. 247). Causes considerable damage to commercial catches and gear (Ref. 6885). Utilized fresh, dried or salted, and frozen; fins, hides and livers are also used, with fins having particular value; can be broiled and baked (Ref. 9988).
Exhibit ovoviparity (aplacental viviparity), with embryos feeding on other ova produced by the mother (oophagy) after the yolk sac is absorbed (Ref. 50449). Litter size is up to 4 young (Ref. 247). Distinct pairing with embrace (Ref. 205).
Compagno, L.J.V., 1984. FAO Species Catalogue. Vol. 4. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part 1 - Hexanchiformes to Lamniformes. FAO Fish. Synop. 125(4/1):1-249. Rome: FAO. (Ref. 247)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
Fisheries: minor commercial; gamefish: yes
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.7813 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00933 (0.00407 - 0.02141), b=3.04 (2.84 - 3.24), based on LWR estimates for this Family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 4.5 ±0.80 se; Based on food items.
Resilience (Ref. 69278
): Very Low, minimum population doubling time more than 14 years (Fec=4).
Vulnerability (Ref. 59153
): High vulnerability (59 of 100) .