''Nephrops norvegicus'', known variously as the Norway lobster, Dublin Bay prawn, ' (compare
langostino
''Langostino'' is a Spanish word with different meanings in different areas. In the United States, it is commonly used in the restaurant trade to refer to the meat of the squat lobster, which is neither a true lobster nor a prawn. Squat lobsters ...
) or ''
scampi
Scampi, also called Dublin Bay Prawn or Norway Lobster (''Nephrops norvegicus''), is an edible lobster of the order '' Decapoda''. It is widespread in the Mediterranean and northeastern Atlantic, from North Africa to Norway and Iceland, and i ...
'', is a slim, orange-pink
lobster
Lobsters are a family (biology), family (Nephropidae, Synonym (taxonomy), synonym Homaridae) of marine crustaceans. They have long bodies with muscular tails and live in crevices or burrows on the sea floor. Three of their five pairs of legs ...
which grows up to long, and is "the most important commercial crustacean in Europe".
It is now the only extant species in the genus ''
Nephrops
''Nephrops'' is a genus of lobsters comprising a single extant species, ''Nephrops norvegicus'' (the Norway lobster or Dublin Bay prawn), and several fossil species. It was erected by William Elford Leach in 1814, to accommodate ''N. norvegicus' ...
'', after several other species were moved to the closely related genus ''
Metanephrops
''Metanephrops'' is a genus of lobsters, commonly known as scampi. Important species for fishery include '' Metanephrops australiensis'' (Australian scampi) and ''Metanephrops challengeri'' (New Zealand scampi). It differs from other lobsters su ...
''. It lives in the north-eastern
Atlantic Ocean, and parts of the
Mediterranean Sea, but is absent from the
Baltic Sea and
Black Sea. Adults emerge from their burrows at night to feed on worms and fish.
Description
''Nephrops norvegicus'' has the typical body shape of a
lobster
Lobsters are a family (biology), family (Nephropidae, Synonym (taxonomy), synonym Homaridae) of marine crustaceans. They have long bodies with muscular tails and live in crevices or burrows on the sea floor. Three of their five pairs of legs ...
, albeit narrower than the large genus ''
Homarus''.
It is pale orange in colour, and grows to a typical length of , or exceptionally long, including the tail and
claws.
A
carapace
A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...
covers the animal's
cephalothorax
The cephalothorax, also called prosoma in some groups, is a tagma of various arthropods, comprising the head and the thorax fused together, as distinct from the abdomen behind. (The terms ''prosoma'' and ''opisthosoma'' are equivalent to ''cepha ...
, while the abdomen is long and segmented, ending in a broad tail fan.
The first three pairs of legs bear claws, of which the first are greatly elongated and bear ridges of
spines.
Of the two pairs of
antennae, the second is the longer and thinner.
There is a long, spinous
rostrum, and the
compound eyes are
kidney-shaped, providing the name of the genus, from the
Greek roots (''
nephros'', "kidney") and ''ops'' ("eye").
Distribution
''Nephrops norvegicus'' is found in the north-eastern
Atlantic Ocean and
North Sea as far north as
Iceland and northern
Norway, and south to
Portugal. It is not common in the
Mediterranean Sea except in the
Adriatic Sea, notably the north Adriatic. It is absent from both the
Black Sea and the
Baltic Sea.
Due to its ecological demands for particular sediments, ''N. norvegicus'' has a very patchy distribution, and is divided into over 30 populations. These populations are separated by inhospitable terrain, and adults rarely travel distances greater than a few hundred metres.
Ecology
''Nephrops norvegicus'' adults prefer to inhabit muddy seabed sediments, with more than 40 percent silt and clay.
Their
burrow
An Eastern chipmunk at the entrance of its burrow
A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion. Burrows provide a form of sh ...
s are semi-permanent, and vary in structure and size. Typical burrows are deep, with a distance of between the front and back entrances.
Norway lobsters spend most of their time either lying in their burrows or by the entrance, leaving their shelters only to forage or mate.
Diet
''Nephrops norvegicus'' is a
scavenger
Scavengers are animals that consume dead organisms that have died from causes other than predation or have been killed by other predators. While scavenging generally refers to carnivores feeding on carrion, it is also a herbivorous feeding b ...
and
predator that makes short foraging excursions, mainly during periods of subdued light. They feed on active prey, including
worms and
fish, which they capture with their
chelipeds and walking legs, and food is conveyed to the mouth using the anterior walking legs, assisted by the
maxillipeds.
There is evidence that ''Nephrops norvegicus'' is a major eater of
jellyfish.
Parasites and symbionts
''Nephrops norvegicus'' is the
host to a number of
parasites and
symbionts
Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasit ...
. A number of
sessile organisms attach to the
exoskeleton of ''N. norvegicus'', including the
barnacle
A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in eros ...
''
Balanus crenatus
''Balanus crenatus'' is a species of acorn barnacle in the Balanidae family. It is found in the North Pacific and the North Atlantic Ocean.
Description
The shell of ''B. crenatus'' is made of six calcareous plates and grows up to across. The up ...
'' and the
foraminiferan ''
Cyclogyra'', but overall ''Nephrops'' suffers fewer infestations of such
epibionts than other decapod crustaceans do.
In December 1995, the
commensal ''
Symbion pandora'' was discovered attached to the
mouthparts
Mouthparts may refer to:
* The parts of a mouth
** Arthropod mouthparts
*** Insect mouthparts
{{disambig ...
of ''Nephrops norvegicus'', and was found to be the first member of a new
phylum
In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature f ...
,
Cycliophora, a finding described by
Simon Conway Morris as "the zoological highlight of the decade". ''S. pandora'' has been found in many populations of ''N. norvegicus'', both in the north Atlantic and in the Mediterranean Sea. Individuals may be found on most segments of the lobster's mouthparts, but are generally concentrated on the central parts of the larger mouthparts, from the
mandible to the third
maxilliped.
The most significant parasite of ''N. norvegicus'' is a
dinoflagellate
The dinoflagellates (Greek δῖνος ''dinos'' "whirling" and Latin ''flagellum'' "whip, scourge") are a monophyletic group of single-celled eukaryotes constituting the phylum Dinoflagellata and are usually considered algae. Dinoflagellates are ...
of the genus ''
Hematodinium'', which has caused
epidemic infection in fished populations of ''N. norvegicus'' since the 1980s.
''Hematodinium'' is a genus that contains major pathogens of a wide variety of decapod crustaceans, although its internal taxonomy is poorly resolved.
The species which attacks ''N. norvegicus'' causes a
syndrome originally described as "post-moult syndrome", in which the
carapace
A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...
turns opaque and becomes highly pigmented, the
haemolymph becomes milky white, and the animal appears
moribund.
Other parasites of ''N. norvegicus'' include the
gregarine
The gregarines are a group of Apicomplexan alveolates, classified as the Gregarinasina or Gregarinia. The large (roughly half a millimeter) parasites inhabit the intestines of many invertebrates. They are not found in any vertebrates. However, g ...
protozoa
Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic tissues and debris. Histo ...
n ''
Porospora nephropis'', the
trematode ''
Stichocotyle nephropis'' and the
polychaete ''
Histriobdella homari''.
Life cycle
The typical
life span of ''N. norvegicus'' is 5–10 years, reaching 15 years in exceptional cases. Its
reproductive cycle varies depending on geographical position: "the periods of hatching and spawning, and the length of the incubation period, vary with latitude and the breeding cycle changes from annual to biennial as one moves from south to north".
Incubation of eggs is
temperature-dependent, and in colder climates, the duration of the incubation period increases. This means that, by the time hatching occurs, it may be too late for the females to take part in that year's breeding cycle. In warmer climates, the combined effects of recovery from
moulting
In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...
and ovary maturation mean that spawning can become delayed. This, in turn, has the effect of the female missing out a year of egg carrying.
Adult male ''Nephrops norvegicus''
moult once or twice a year (usually in late winter or spring) and adult females moult up to once a year (in late winter or spring, after hatching of the eggs).
In annual breeding cycles, mating takes place in the spring or winter, when the females are in the soft, post-moult state. The ovaries mature throughout the spring and summer months, and egg-laying takes place in late summer or early autumn. After spawning, the berried (egg-carrying) females return to their burrows and remain there until the end of the incubation period. Hatching takes place in late winter or early spring. Soon after hatching, the females moult and mate again.
During the planktonic larval stage (typically 1 to 2 months in duration) the nephrops larvae exhibit a diel vertical migration behaviour as they are dispersed by the local currents. This complex biophysical interaction determines the fate of the larvae; the overlap between advective pathway destination and spatial distributions of suitable benthic habitats must be favourable in order for the larvae to settle and reach maturity.
Fisheries
The muscular tail of ''Nephrops norvegicus'' is frequently eaten, and its meat is known as ''
scampi
Scampi, also called Dublin Bay Prawn or Norway Lobster (''Nephrops norvegicus''), is an edible lobster of the order '' Decapoda''. It is widespread in the Mediterranean and northeastern Atlantic, from North Africa to Norway and Iceland, and i ...
''. The ''N. norvegicus'' is eaten only on special occasions in
Spain and Portugal, where it is less expensive than the common lobster, ''
Homarus gammarus''. ''N. norvegicus'' is an important species for
fisheries
Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life; or more commonly, the site where such enterprise takes place ( a.k.a. fishing ground). Commercial fisheries include wild fisheries and fish farms, both ...
, being caught mostly by
trawling. Around 60,000
tonnes are caught annually, half of it in the
United Kingdom's
waters.
Besides the established trawling fleets, a significant number of fleets using
lobster creels have developed. The better size and condition of lobsters caught by this method yield prices three to four times higher than animals netted by trawling. Creel fishing was found to have a reduced impact on the seafloor, require lower fuel consumption, and allow fishermen with smaller boats to participate in this high-value fishery. It has therefore been described as a reasonable alternative to demersal towed gears, and the allocation of additional fishing rights for this type of take has been suggested.
The North East Atlantic individual biological stocks of Nephrops are identified as functional units. A number of functional units make up the sea areas over which a total allowable catch (TAC) is set annually by the EU Council of Ministers. For example, the TAC set for North Sea Nephrops is based on the aggregate total tonnage of removals recommended by science for nine separate functional unit areas. This method has attracted criticism because it can promote the
overexploitation
Overexploitation, also called overharvesting, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable to replenish. The term app ...
of a specific functional unit even though the overall TAC is under-fished. In 2016, the UK implemented a package of emergency technical measures with the cooperation of the fishing industry aimed at reducing fishing activity to induce recovery of the Nephrops stock in the Farn(e) Deeps off North East England which was close to collapse. A stock assessment completed in 2018 by the International Council for the Exploration of the Sea (ICES) shows that fishing pressure has been cut and this stock is now below FMSY and that stock size is above MSY Btrigger meaning that the Farne Deeps nephrops stock is being fished at a sustainable level. However, ICES also warn that any substantial transfer of the current surplus fishing opportunities from other functional units to the Farne Deeps would rapidly lead to overexploitation. This suggests that controls on fishing effort should continue at least until the biomass reaches a size that is sustainable when measured against the level of fishing activity by all fishermen wanting to target the stock.
Discards from ''Nephrops'' fishery may account for up to 37% of the
energy requirements of certain marine
scavenger
Scavengers are animals that consume dead organisms that have died from causes other than predation or have been killed by other predators. While scavenging generally refers to carnivores feeding on carrion, it is also a herbivorous feeding b ...
s, such as the
hagfish ''
Myxine glutinosa''. Boats involved in ''Nephrops'' fishery also catch a number of fish species such as
plaice and
sole, and it is thought that without that revenue, ''Nephrops'' fishery would be economically unviable.
Taxonomic history
''Nephrops norvegicus'' was one of the species included by
Carl Linnaeus in his 1758
10th edition
1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit of counting or measurement. For example, a line segment of ''unit length'' is a line segment of length 1. I ...
of ', the starting point for
zoological nomenclature. In that work, it was listed as ', with a
type locality
Type locality may refer to:
* Type locality (biology)
* Type locality (geology)
See also
* Local (disambiguation)
* Locality (disambiguation)
{{disambiguation ...
of ' ("in the Norwegian sea"). In choosing a
lectotype,
Lipke Holthuis restricted the type locality to the
Kattegat at the
Kullen Peninsula in southern
Sweden
Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...
().
Two
synonyms
A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...
of the species have been published
– "''Astacus rugosus''", described by the eccentric zoologist
Constantine Samuel Rafinesque
Constantine Samuel Rafinesque-Schmaltz (; October 22, 1783September 18, 1840) was a French 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ultimat ...
in 1814 from material collected in the
Mediterranean Sea, and "''Nephropsis cornubiensis''", described by
Charles Spence Bate and
Joshua Brooking Rowe
Joshua () or Yehoshua ( ''Yəhōšuaʿ'', Tiberian: ''Yŏhōšuaʿ,'' lit. 'Yahweh is salvation') ''Yēšūaʿ''; syr, ܝܫܘܥ ܒܪ ܢܘܢ ''Yəšūʿ bar Nōn''; el, Ἰησοῦς, ar , يُوشَعُ ٱبْنُ نُونٍ '' Yūšaʿ ...
in 1880.
As new genera were erected, the species was moved, reaching its current position in 1814, when
William Elford Leach erected the genus ''
Nephrops
''Nephrops'' is a genus of lobsters comprising a single extant species, ''Nephrops norvegicus'' (the Norway lobster or Dublin Bay prawn), and several fossil species. It was erected by William Elford Leach in 1814, to accommodate ''N. norvegicus' ...
'' to hold this species alone.
Seven
fossil species have since been described in the genus.
Populations in the
Mediterranean Sea are sometimes separated as "''Nephrops norvegicus'' var. ''meridionalis'' Zariquiey, 1935", although this taxon is not universally considered valid.
See also
*
References
Citations
General and cited references
* Murray, F., & Cowie, P. R. (2011)
"Plastic contamination in the decapod crustacean ''Nephrops norvegicus'' (Linnaeus, 1758)" ''Marine Pollution Bulletin'', 62(6), 1207-1217. .
External links
FAOADRIAMED
FAO Species Fact Sheet*
{{Authority control
Commercial crustaceans
Crustaceans described in 1758
Crustaceans of the Atlantic Ocean
Edible crustaceans
Taxa named by Carl Linnaeus
True lobsters