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No Records
Occasional
Range

Map base conforms with ICES grid squares.

Porbeagle Shark, Atlantic Mackerel Shark, Blue Dog, Bottle-nosed 
Shark, Beaumaris Shark, Requin-Taupe Commun (Fr), Marrajo 
Sardinero (Es), Tiburón Sardinero (Es), Tintorera (Es).

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).

COMMON NAMES

•  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.

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).

SYNONYMS

DISTRIBUTION

APPEARANCE

???

VU

Text & Illustrations © Shark Trust 2009

Lateral View (

♀)

Ventral View (

♀)

Porbeagle Shark

Lamna nasus

N

AT

M

ED

CR

NE A

TL:

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SIMILAR SPECIES

Carcharodon carcharias, White Shark
Isurus oxyrinchus, Shortfin Mako Shark
Isurus paucus, Longfin Mako Shark
Prionace glauca, Blue Shark

 

Porbeagle Shark

Text & Illustrations © Shark Trust 2009

(Not to scale)

Supported by:

Lamna nasus,
Porbeagle Shark

Carcharodon carcharias,
White Shark

Isurus oxyrinchus,
Shortfin Mako Shark

Isurus paucus,
Longfin Mako Shark

Prionace glauca,
Blue Shark

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Porbeagle Shark 

Lamna nasus

TEETH

The teeth are moderately large and 
blade-like with lateral cusps. The 
first upper lateral teeth have nearly 
straight cusps (Roman, Unknown).

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

(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).

Text & Illustrations © Shark Trust 2009

ECOLOGY AND BIOLOGY

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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).

IUCN RED LIST ASSESSMENT

Vulnerable (2005).
Critically Endangered in northeast Atlantic.

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.

•  Handle with care.
•  Large shark.
•  Powerful jaws and sharp teeth.
•  Abrasive skin.

 

Porbeagle Shark

Text & Illustrations © Shark Trust 2009

Supported by:

THREATS, CONSERVATION, LEGISLATION

HANDLING AND THORN ARRANGEMENT

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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.

REFERENCES

Porbeagle Shark 

Lamna nasus

Text & Illustrations © Shark Trust 2009

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.

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