Porbeagle Shark Lamna nasus - The Shark Trust

Lateral View (♀) 

Porbeagle Shark Lamna nasus 

COMMON NAMES 

Porbeagle Shark, Atlantic Mackerel Shark, Blue Dog, Bottle-nosed 

Shark, Beaumaris Shark, Requin-Taupe Commun (Fr), Marrajo 

Sardinero (Es), Tiburón Sardinero (Es), Tintorera (Es). 

SYNONYMS 

Squalus glaucus (Gunnerus, 1758), Squalus cornubicus (Gmelin, 1789), 

Squalus pennanti (Walbaum, 1792), Lamna pennanti (Desvaux, 1851), 

Squalus monensis (Shaw, 1804), Squalus cornubiensis (Pennant, 1812), 

Squalus selanonus (Walker, 1818), Selanonius walkeri (Fleming, 1828), 

Lamna punctata (Storer, 1839), Oxyrhina daekyi (Gill, 1862), Lamna 

philippi (Perez Canto, 1886), Lamna whitleyi (Phillipps, 1935). 

DISTRIBUTION 

In the northern 

hemisphere, the 

Porbeagle Shark 

occurs only in the 

North Atlantic and 

Mediterranean, 

whilst in the 

southern 

hemisphere it 

is found in a 

circumglobal band 

(Francis et al, 2008). 

Map base conforms with ICES grid squares. 

Text & Illustrations © Shark Trust 2009 

No Records 

Occasional 

Range 

Ventral View (♀) 

APPEARANCE 

• Heavily built but streamlined mackerel shark. 

• Moderately long conical snout with a relatively large eyes. 

• Large first dorsal fin with a conspicuous white free rear tip. 

• Second dorsal fin and anal fin equal-sized and set together. 

• Lunate caudal fin with strong keel and small secondary keel. 

• Dorsally dark blue to grey with no patterning. 

• Ventrally white. 

• Maximum length of 365cm, though rarely to this size. 

The Porbeagle Shark is a large, streamlined mackerel shark with a 

conical snout and powerful body. The first dorsal fin is large and 

originates above or slightly behind the pectoral fins. It has a free rear 

tip which is white. The second dorsal fin is tiny and is set above the 

anal fin, to which it is comparable in size. The caudal fin is strong and 

lunate with a small terminal notch. The caudal keel is strong and, 

uniquely for the northeast Atlantic, a smaller secondary caudal keel is 

present. Dorsally, it is dark blue to grey with no patterning. Ventrally it 

is white with darker patterning on the edges of the pectoral fins. The 

maximum recorded length is 365cm but animals less than 300cm in 

length are much more commonly encountered (Compagno, 2001). 

In European waters it can be confused with the White Shark, 

Carcharodon carcharias, the Shortfin Mako Shark. Isurus oxyrinchus, 

the Longfin Mako Shark, Isurus paucus, and the Blue Shark, Prionace 

glauca. However, it is distinguished from all of these species by its 

white free rear tip on the first dorsal fin and the secondary caudal keel. 

NE ATL MED 

CR 

NE ATL: 

??? VU

SIMILAR SPECIES 

Carcharodon carcharias, White Shark 

Isurus oxyrinchus, Shortfin Mako Shark 

Isurus paucus, Longfin Mako Shark 

Prionace glauca, Blue Shark 

(Not to scale) 

Supported by: 

Carcharodon carcharias, 

White Shark 

Isurus paucus, 

Longfin Mako Shark 



Lamna nasus, 


Isurus oxyrinchus, 

Shortfin Mako Shark 

Prionace glauca, 

Blue Shark

TEETH 


The teeth are moderately large and 

blade-like with lateral cusps. The 

first upper lateral teeth have nearly 

straight cusps (Roman, Unknown). 

ECOLOGY AND BIOLOGY 

HABITAT 

The Porbeagle Shark can be found from the surface to 715m in 

coastal and pelagic waters (Roman, Unknown). Tagging studies 

have revealed a preference for shelf waters, although one tagged 

individual travelled 1,800km into the mid-Atlantic. There is only 

one record of a tagged shark crossing the Atlantic from Ireland 

to Canada and it appears that the two populations are separate 

(Francis et al., 2008). While it does not appear to enter freshwater, 

catches from a brackish estuary in Argentina have been reported 

(Roman, Unknown). 

In the southern hemisphere it may move further north, out of 

its usual range, during the cooler months but is not found further 

north than 35 o S during the summer. Around Australia it may move 

into subtropical waters during the winter. It appears to be limited 

to waters between 1–23 o C, with abundance declining above 19 o C 

(Francis et al., 2008). 

In the North Atlantic, temperatures of -1–15 o C have been 

recorded with a mean of 7–8 o C. Its abundance is also governed by 

seasonal variations with records of Porbeagles moving north along 

the coast of North America during the spring and early summer 

with the return migration in late autumn (Francis et al., 2008). 

The Porbeagle Shark appears to segregate by sex and size. In 

Spanish waters, males dominate catches over females in a ratio of 

2:1, while 30% more females than males are caught off Scotland. In 

the Bristol Channel, smaller individuals are found with a dominance 

of males over females (Francis et al., 2008). This segregation is likely 

to have evolved as a mechanism of reducing predation of neonates 

by adults and also to limit breeding to appropriate seasons (Roman, 

Unknown). 

DIET 

The Porbeagle Shark is primarily a piscivore with teleost fish 

constituting 90% of the diet of some individuals. It has been 

reported that pelagic fish are preferred during the spring and 

summer when abundant. During the autumn and winter, groundfish 

are the dominant prey. (Roman, Unknown). Compagno (2001) 

lists the most common prey items as mackerels, pilchards and 

herring, various gadoids including cod, hakes, haddock, cusk, and 

whiting, and john dories, dogfishes and hound sharks (Squalus and 

Galeorhinus spp.), and squids (Compagno, 2001). 


REPRODUCTION 

Species in the family lamnidae are viviparous with embryos 

nourished either by a continual supply of unfertilized eggs (oophagy) 

or through feeding on less developed siblings (adelphophagy, known 

only from the Sandtiger Shark, Carcharias taurus) (Martin, 1984). The 

Porbeagle Shark employs oophagy to supply nutrients to embryos 

once the original yolk-sac supply has been depleted. Its ovaries are 

well adapted to this task and may contain up to 200,000 unfertilised 

eggs, measuring 1.5–5mm in diameter (Lombardi, 1998). 

It has been reported from the northwest Atlantic that females 

mature at 200–219cm and 50% are mature by 208cm. Males 

mature at 155–177cm with 50% mature by 166cm. In the southern 

hemisphere off New Zealand, females mature at 170–180cm and 

males mature at 140–150cm (Francis et al., 2008). 

In the North Atlantic mating occurs in autumn and winter and 

the females give birth during spring and summer after an 8–9 

month gestation period. It appears that populations in the southern 

hemisphere may breed at different times but data is lacking. The 

females give to birth to a litter of 1–5 pups, although 4 is normal with 

2 pups to each uterus. Each of these pups measures 58–67cm long at 

birth (Francis et al., 2008).

Supported by: 

COMMERCIAL IMPORTANCE 

One of the most valuable elasmobranch species to commercial 

fisheries, the Porbeagle Shark is taken across its range in targeted 

longline fisheries and its flesh is used for human consumption, its 

fins for sharkfin soup, its liver oil for vitamins and its carcass can 

be processed for fishmeal. It is also regularly taken as bycatch, 

particularly in tuna longline fisheries in the South Pacific but also in 

trawl, handline and gillnet fisheries. It is an important recreational 

species on both sides of the North Atlantic (Stevens et al., 2006). 

The Porbeagle Shark has been fished commercially since the early 

1800’s, principally by Scandinavian fishers, to provide flesh for 

human consumption, fins for sharkfin soup, liver oil for vitamins 

and carcass’ for fishmeal (Gauld, 1989). Global catches peaked in the 

1960’s at around 9,000 tons, followed by a rapid decline to 1,300– 

2,600 tons in the 1990’s (Francis et al., 2008). Catches in the North 

Atlantic have varied wildly during the 20th century, particularly in 

the case of the Norwegian targeted fishery. In 1926, 279 tons were 

landed. This increased to 3,884 tons in 1933 followed by a sharp 

decline due to the reduction in fishing effort during the Second 

World War. In 1947, catches were back up to 2,824 tons but then 

declined steadily to 207 tons in 1970 and just 25 tons in 1994. The 

fishery attempted to boost catches by moving across to the west 

Atlantic stock but had to switch focus to other species such as the 

Shortfin Mako Shark, Isurus oxyrinchus, and swordfish (Compagno, 

2001). 

Currently in the North Atlantic, the Porbeagle Shark is taken 

primarily in directed longline fisheries, although there is some 

bycatch from bottom trawls, handlines and gill nets. The majority of 

the catch in the southern hemisphere is bycatch from tuna longline 

fleets in the South Pacific and southern Indian Ocean, although 

there is a small Norwegian targeted fishery (Francis et al., 2008). The 

only landings reported to the FAO from the southern hemisphere 

are from the New Zealand fishery, meaning that the fishing 

mortality for the southern stock is almost unknown (Compagno, 

2001). 

In the northeast Atlantic, the Porbeagle Shark is covered by EC 

Regulation No. 1185/2003 which prevents the removal of its fins 

at sea and the subsequent discard of the body. This applies to all 

vessels operating in EC waters, as well as to EC vessels operating 

anywhere (CPOA Sharks, 2009). In addition, a total allowable catch 

(TAC) applies to this species in European Waters. In 2008 this TAC 

was 581 tons. Despite scientific advice for a zero TAC for 2009, it 

was lowered by only 25% to 436 tons with a maximum landing 

size of 210cm designed to protect breeding individuals (European 

Commission, 2008). In 2010, the TAC was finally reduced to zero 

meaning the species cannot be landed by commercial fishers in the 

EU. 

IUCN RED LIST ASSESSMENT 

Vulnerable (2005). 

Critically Endangered in northeast Atlantic. 

THREATS, CONSERVATION, LEGISLATION HANDLING AND THORN ARRANGEMENT 


• Handle with care. 

• Large shark. 

• Powerful jaws and sharp teeth. 

• Abrasive skin. 

Porbeagle Shark

REFERENCES 


COMPAGNO, L. J. V. 2001. Sharks of the World: An Annotated and 

Illustrated Catalogue of Shark Species Known to Date. Volume 

2. Bullhead, Mackerel and Carpet Sharks (Heterodontiformes, 

Lamniformes and Orectolobiformes). FAO. Rome, Italy. 

FRANCIS, M. P., NATANSON, L. J., CAMPANA, S. E. 2008. The Biology 

and Ecology of the Porbeagle Shark, Lamna nasus. In: Camhi, 

M. D., Pikitch, E. K., Babcock, E. A. (Eds.) 2008. Sharks of the 

Open Ocean: Biology, Fisheries and Conservation. Blackwell 

Publishing Ltd. Oxford, UK. 

GAULD, J. A. 1989. Records of Porbeagles Landed in Scotland, with 

Observations on the Biology, Distribution and Exploitation 

of the Species. Department of Agriculture and Fisheries for 

Scotland. 

LOMBARDI, J. 1998. Comparative Vertebrate Reproduction. 

Springer. New York, USA. 

MARTIN, R. A. 1994. From Here to Maternity. Diver Magazine, April 

1994. 

ROMAN, B. Unknown. Porbeagle. Florida Museum of Natural 

History. www.flmnh.ufl.edu/fish/. 

STEVENS, J., FOWLER, S.L., SOLDO, A., MCCORD, M., BAUM, J., 

ACUÑA, E., DOMINGO, A., FRANCIS, M. 2006. Lamna nasus. In: 

IUCN 2008. 2008 IUCN Red List of Threatened Species. www. 

iucnredlist.org. 


Text: Richard Hurst. 

Illustrations: Marc Dando. 

Citation 

Shark Trust; 2010. An Illustrated Compendium of Sharks, Skates, Rays 

and Chimaera. Chapter 1: The British Isles and Northeast Atlantic. Part 

2: Sharks. 

Any ammendments or corrections, please contact: 

The Shark Trust 

4 Creykes Court, The Millfields 

Plymouth, Devon PL1 3JB 

Tel: 01752 672008/672020 

Email: enquiries@sharktrust.org 

For more ID materials visit www.sharktrust.org/ID. 

Registered Company No. 3396164. 

Registered Charity No. 1064185

Porbeagle Shark Lamna nasus - The Shark Trust

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