| Photo |
Porbeagle
© Unknown
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| Range Map |
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| Systematics |
Phylum: Vertebates (Chordata)
Class: Carlilagenous Fishes (Chondrichthyes)
Order: Mackerel sharks (Lamniformes)
Family: Mackerel sharks (Lamnidae)
Genus: Lamna (Lamna)
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| Name |
| Scientific: | Lamna nasus |
| German: | Heringshai |
| English: | Porbeagle |
| French: | Requin-taupe commun |
| Spanish: | Marrajo sardinero |
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| Appearance |
Spindle-shaped, heavy built body. Moderately long conical snout. First dorsal fin is large, second one is minute. Large gill slits. Two pairs of caudal keels on peduncle whereas the lower pair is shorter than the top one.
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| Coloration |
Blue-grey with a light ventral surface. Free rear tip of first dorsal fin is conspicuously white colored.
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| Distribution |
Mainly in colder waters of both hemispheres. Western Atlantic: Newfoundland, Gulf of St. Lawrence. Eastern Atlantic: Iceland, western Barent Sea to Gibraltar, Mediterranean, Madeira. South Africa (western Cape Province), South central Indo-Pacific. Southwestern South Pacific: Australia, Tasmania, New Zealand. Southeastern Pacific: Chile. Subarctic waters off South Georgia, Kerguelen Islands.
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| Biology |
Abundant in littoral and epipelagic waters, mainly over the continental shelves. Porbeagles prefer waters of colder temperatures (under 18°C) and therefore do normally not occur in tropical and subtropical waters (only during winter months in the Mediterranean). Found mainly in surface waters down to about 350 m. A very active and fast swimming species. Porbeagles can be found singly or in feeding aggregations.
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| Feeding |
Feed on schooling fishes such as mackerels, herrings, various gadoids (e.g cods, hakes etc.), small shark species (tope, dogfish) and squid.
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| Size |
Average size between 150 cm and 180 cm (135 kg), maximum length up to about 365 cm and 230 kg.
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| Reproduction |
Aplacental viviparity (ovoviviparity), embryos feed on eggs (oophagous). Almost allways 4 pups per litter. Gestation period is not known. Size at birth is between 60 cm to 75 cm. Pups show a fast growth and are born in pelagic waters. Females reach sexual maturity at about 150 cm (about 5 years old). Maximum age about 30 years.
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| Similar Species |
Shortfin Mako but the makos are more slender and do not have a second keel under the first one on the caudal peduncle.
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| Endangerment |
Status in the IUCN
Red List(1994):
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| Main criterion: |
 LR/nt (Low Risk/Near Threatened (1994)) |
| Sub criterion: |
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| Trend: |
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| Danger to Humans |
Harmless, although some see this species as "potentially dangerous" due to the size and jaws but no accident has ever been recorded.
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