This species is known by a variety of common names. The most common name is giant tiger prawn (shrimp). However, they are also called Asian prawn shrimp, ghost prawn, and grass shrimp.
Giant tiger prawns have eyestalks on their heads which enable them to detect predators and search out prey. The eyes are called ommatidia, and are composed of clusters of photoreceptors. Since giant tiger prawns are nocturnal, they must have very good vision at night to detect predators and prey, but can also see well in daylight. Eyestalks have the ability to change their optical properties based on light-dark adaptations. In dark light, eyestalks receive light from a wide angle and create a superposition image, formed by mirrors in the sides of the cornea instead of by lenses. This superposition image is very effective at detecting movement. In bright light, eyestalks have the ability to see almost 360 degrees and form apposition images, a more efficient detector of light than superposition images. Molting Inhibition Hormone (MIH), which controls the molting cycle, is produced in the eyestalks; a recent study showed that when eyestalks are ablated, molting is accelerated. It is also known that ablating eyestalks in this species induces ovulation and jeopardizes growth. Giant tiger prawns also have flagellae on their antennae, which detect predators and prey through vibrations. These flagellae also have chemosensors, which detect amino acids and differences in pH, salinity and food stimulants.
Communication Channels: visual ; tactile ; chemical
Other Communication Modes: vibrations
Perception Channels: visual ; tactile ; vibrations ; chemical
This species has no special conservation status.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
Eggs begin development by slowly sinking to the bottom of outer littoral areas. Giant tiger prawns develop through a complex life cycle beginning with three larval stages. Naupilii hatch twelve to fifteen hours after spawning is completed and look like tiny spiders. Larvae at this stage do not feed, instead surviving on their yolks as they are carried by tidal currents from open ocean towards shore. Naupilii larvae pass through six quick molts, increasing their body size. Individuals in the next larval stage, called protozoea, are identified by increased body size and length, the appearance of feathery appendages and, though still planktonic, beginning to feed. After molting three more times, protozoea proceed into the mysis larval stage. At this stage, they begin to have characteristics of adult prawns including segmented bodies, eye stalks, and tails. Mysis larvae molt three more times, becoming postlarvae. At this point in the life cycle, they change from planktonic to benthic feeding. This entire process takes two to three weeks. Prawns continue to molt through a juvenile phase, lasting 1-6 months. Juveniles and adults are distinguished mainly by location and carapace length. Carapace lengths of juveniles range from 2.2-11 mm and they are found mainly in estuarine areas located at the mouth or middle of bays and mangroves while adults are found in outer littoral areas of full salinity, and have carapace lengths ranging from 37-81 mm.
Development - Life Cycle: metamorphosis
This species is invasive in waters around the United States. Diseases carried by giant tiger prawns are highly contagious and can infect native shrimp populations, harming local fishing industries.
It has been estimated that up to 38% of native mangrove forests in Asia have been destroyed to be converted into ponds for shrimp farming, triggering erosion and harming habitat for mollusks and many other species, including shorebirds. Farming pools are sprayed with many chemicals and antibiotics to maximize shrimp production and these chemicals can enter natural waterways, harming animals and humans alike. These pools are often abandoned after a few years and there is typically no effort to return these lands to their original conditions.
Farming of Giant tiger prawns constitutes 47% of total world shrimp production giving it significant economic importance, particularly in Asian countries. With a high demand in Asian and international markets, building and running farms to produce these shrimp can be highly profitable and create many jobs.
Positive Impacts: food
Giant tiger prawns are detritivores and consumers of small invertebrates. They also are prey for many species of fishes and invertebrates.
Giant tiger prawns are a host for a variety of viruses, all of which are extremely contagious within populations and cause high mortality rates. The Yellowhead virus, originally isolated from this species, causes the hepatopancreas and cephalothorax to become discoloured and swollen. WSSV (White Spot Syndrome Virus) causes white spot disease, symptoms of which include lesions and white deposits on the skin and connective tissue. There are two types of Baculovirus infections commonly seen in these prawns: Baculoviral Midgut Gland Necrosis, which affects mainly larvae, and Monodon baculovirus disease, which is typically followed by secondary bacterial infections. These diseases are of particular concern in aquaculture environments and in areas where this species has been introduced.
Giant tiger prawns are also host to a number of protozoan ectoparasites and endoparasites. Their ectoparasites attach themselves to the gills and limbs, potentially interfering with breathing and motility, while their endoparasites live in the gut and can affect nutrient absorption. This species is also known to host of a number of fungal microsporidians.
Commensal/Parasitic Species:
In their first larval stage, giant tiger prawns feed on their yolk reserves. Later larval stages filter feed on plankton, diatoms, and other small organisms in the water column before becoming benthic feeders with a diet composed of organisms such as polycheate worms (Sabellaridae, Spionidae, Unicidae), as well as detritus. In the wild, adult giant tiger prawns feed on mollusks (including squid, blood clams (Arca sp.) and oysters), small crustaceans (including isopods, crabs and their eggs, and young penaeid prawns, including their own species). In aquaculture, these prawns feed on artificial diets consisting mainly of fishmeal; it has been noted that individuals grow more quickly when fed this diet.
Animal Foods: fish; eggs; carrion ; mollusks; aquatic or marine worms; aquatic crustaceans; other marine invertebrates
Plant Foods: phytoplankton
Other Foods: detritus
Foraging Behavior: filter-feeding
Primary Diet: carnivore (Eats non-insect arthropods, Molluscivore , Vermivore, Scavenger ); omnivore ; planktivore ; detritivore
Giant tiger prawns are native to the coasts of the Arabian peninsula and the Pacific and Indian Ocean coasts of Australia, Indonesia, south and southeast Asia, and South Africa. They were accidentally introduced to the United States off the coast of South Carolina in 1988, by an unexpected release from an aquaculture center. They had spread as far south as Florida's coastline by 1990 and, since 2006, have been found in the Gulf of Mexico; they are found along the coastlines of Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina and Texas.
Biogeographic Regions: nearctic (Introduced ); palearctic (Native ); oriental (Native ); ethiopian (Native ); australian (Native ); indian ocean (Native ); atlantic ocean (Introduced ); pacific ocean (Native )
Young giant tiger prawns are most commonly found in estuaries, lagoons and mangroves; they are very tolerant to a range of salinity levels from 2-30 ppt. Adults move into deeper waters and live on rocky or muddy bottoms, ranging in depth from 0-110 m (most commonly at 20-50 m). These shrimps may bury themselves in the substrate during the day, emerging to feed at night. They live in waters ranging from 28-33°C and are unlikely to survive in waters colder than 13°C.
Range depth: 0 to 110 m.
Habitat Regions: temperate ; tropical ; saltwater or marine
Aquatic Biomes: benthic ; coastal ; brackish water
Other Habitat Features: estuarine ; intertidal or littoral
The lifespan for wild and captive giant tiger prawns is about 2 years, though it has been suggested that individuals introduced into the Gulf of Mexico have a lifespan closer to 3 years.
Typical lifespan
Status: wild: 2 to 3 years.
Average lifespan
Status: captivity: 2 years.
Giant tiger prawns have a typical prawn body plan including a head, tail, five pairs of swimming legs (pleopods) and five pairs of walking legs (pereopods), as well as numerous head appendages. A carapace (hard exoskeleton) encloses the cephalothorax. Their heads have a rostrum (an extension of the carapace in front of the eyes) and six to eight dorsal teeth, as well as two to four sigmoidally-shaped ventral teeth. A posterior ridge called the adrostral carina extends from the rostrum to the edge of the epigastric spine, which reaches to the posterior end of the carapace. Their first three pairs of pereopods have claws and they are distinguished from other shrimp species by the lack of an exopod (an external branch) on their fifth pleopodia. The telson at the posterior end of the prawn is unarmed, with no spines.
Giant tiger prawns are identified by distinct black and white stripes on their backs and tails; on their abdomens, these stripes alternate black/yellow or blue/yellow. Base body color varies from green, brown, red, grey, or blue. These prawns are very large, reaching 330 mm or greater in length (largest individual found at 336 mm total length) and are sexually dimorphic, with females are larger than males. At sexual maturity, female carapace lengths range from 47-164 mm and their total lengths from 164-190 mm, while male carapace lengths fall between 37 and 71 mm, with total lengths of up to 134 mm. On average, females weigh 200-320 g and males weigh 100-170 g.
Females have a sperm receptacle (thyelycum) located ventrally on the last thoracic segment. After mating, sperm remain in this receptacle until eggs are released. Females have a pair of internal fused ovaries that extend almost the entire length of their bodies, from the cardiac region of the stomach to the anterior portion of the telson. Males have a copulatory organ (petasma, formed by the longitudinally folded endopods of the first pair of pleopods. The presence of an appendix masculina (an oval flap on the second pleopod) can distinguish males from females. Testes are unpigmented/translucent and are found dorsal to the hepatopancreas under the carapace. The vas deferens is also internal, and arises from the posterior margins of the main axis of the testes. Sperm are released through genital pores on the fifth pereopod.
Range mass: 100 to 320 g.
Range length: 37 to 174 mm.
Other Physical Features: ectothermic ; bilateral symmetry
Sexual Dimorphism: female larger
Throughout their lifetimes, giant tiger prawns face a variety of predators, including birds, comb jellies, crustaceans, and fishes. When adult prawns move from shallow inshore areas to deeper water, their rate of mortality drops.
Giant tiger prawns have developed a variety of defenses to protect themselves from predation. Prawns have spines on either end of their body (a rostrum above the mouth, and a telson located at the dorsal end of the body). Their distinctive stripes and body color, which is similar to their muddy environment, help to camouflage them from predators. These prawns also bury themselves in substrate, not only hiding their bodies but also masking their waste, which would otherwise likely be detected by potential fish predators' chemosensory systems.
Known Predators:
Anti-predator Adaptations: cryptic
Giant tiger prawns are known to mate prior to ovarian maturation; females store sperm in sacs within their closed thelycum until eggs are fully mature. Although little is known regarding specific mating behaviors, it has been noted that this species mates nocturnally, in off-shore waters, shortly after females have molted and their carapaces are still soft (males typically still have hard carapaces during breeding). Copulation begins with a male swimming parallel to a female. The male bends his body and first pair of pleopods with the petasma (caught by the appendix masculina) stretched vertically down, in order to facilitate the forward swinging of the second pair of pleopods. The first pair of pleopods pulls apart the petasmal halves, preventing the loss of sperm during copulation. The pair then takes an abdomen-to-abdomen position. The female exerts pressure on the male's petasma using her 4th pair of pereiopods and a spermatophore (sac of sperm) is thrust into her thyelycum, after which the pair separate. A majority of adult individuals copulate more than once; females are known to spawn 4 times during their lives, at carapace lengths of 50, 62, 66, and 72 mm.
Mating System: polygynandrous (promiscuous)
It is difficult to estimate age at sexual maturity, but males become mature upon reaching an average carapace size of 37 mm, females at 47 mm. Females can produce 248,000-810,000 eggs at a time and are known to spawn up to four times during their lifespan. Once eggs are mature, they are expelled in a greenish-white cloud, along with stored spermatophores, into the ocean where external fertilization occurs. Eggs range in size from 0.27-0.31 mm.
Breeding interval: Females spawn 4 times during their lifespan at carapace lengths of 50, 62, 66, and 72 mm. It is unknown how many times males mate.
Breeding season: This species breeds year round.
Range number of offspring: 248,000 to 810,000.
Range gestation period: 12 to 15 hours.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (External ); broadcast (group) spawning; oviparous ; sperm-storing ; delayed fertilization
Males exhibit no parental involvement after mating. Females invest by yolking and protecting eggs while they are still in their bodies. They exhibit no further parental involvement once eggs and sperm have been released.
Parental Investment: female parental care ; pre-fertilization (Provisioning, Protecting: Female)
Penaeus monodon, commonly known as the giant tiger prawn,[1][2] Asian tiger shrimp,[3][4] black tiger shrimp,[5][6] and other names, is a marine crustacean that is widely reared for food.
Penaeus monodon was first described by Johan Christian Fabricius in 1798. That name was overlooked until 1949, when Lipke Holthuis clarified to which species it referred.[7] Holthuis also showed that P. monodon had to be the type species of the genus Penaeus.[7]
Females can reach about 33 cm (13 in) long, but are typically 25–30 cm (10–12 in) long and weigh 200–320 g (7–11 oz); males are slightly smaller at 20–25 cm (8–10 in) long and weighing 100–170 g (3.5–6.0 oz).[1] The carapace and abdomen are transversely banded with alternative red and white. The antennae are grayish brown. Brown pereiopods and pleopods are present with fringing setae in red.[8]
Its natural distribution is the Indo-Pacific, ranging from the eastern coast of Africa and the Arabian Peninsula, as far as Southeast Asia, the Pacific Ocean, and northern Australia.[9]
It is an invasive species in the northern waters of the Gulf of Mexico[4] and the Atlantic Ocean off the Southern U.S.[10]
The first occurrence of P. monodon in the U.S. was in November 1988. Close to 300 shrimp were captured off the Southeastern shore after an accidental release from an aquaculture facility. This species can now be caught in waters from Texas to North Carolina. Although P. monodon has been an invasive species for many years, it has yet to grow large, established populations.[11] Escapes in other parts of the world, though, have led to established P. monodon populations, such as off West Africa, Brazil, and the Caribbean.[12][13]
P. monodon is suited to inhabit a multitude of environments.[14] They mainly occur in Southeastern Asia, but are widely found.[14] Juveniles of P. monodon are generally found in sandy estuaries and mangroves, and upon adulthood, they move to deeper waters (0- 110 m) and live on muddy or rocky bottoms.[15] The P. monodon has shown to be nocturnal in the wild, burrowing into substrate during the day, and coming out at night to feed.[16] P. monodon typically feed on detritus, polychaete worms, mollusks, and small crustaceans.[16][17] They feed on algae, as well. Due to their nutrient-rich diet, these shrimp are unable to consume phytoplankton because of their feeding appendages, but they are able to consume senescent phytoplankton.[18] They also commence mating at night, and can produce around 800,000 eggs.[14]
P. monodon is the second-most widely cultured prawn species in the world, after only whiteleg shrimp, Litopenaeus vannamei. In 2009, 770,000 tonnes were produced, with a total value of US$3,650,000,000.[1] P. monodon makes up nearly 50% of cultured shrimp alone.[19]
The prawn is popular to culture because of its tolerance to salinity and very quick growth rate,[11] but they are very vulnerable to fungal, viral, and bacterial infections.[20] Diseases such as white spot disease and yellowhead disease have led to a great economic impact in shrimp industries around the globe.[21] They can receive transmitted diseases from other crustaceans such as the Australian red claw crayfish (Cherax quadricarinatus), which is susceptible to yellowhead disease and has shown to transmit it to P. monodon in Thailand.[22]
Black tiger shrimp's susceptibility to many diseases engenders economic constraints towards the black tiger shrimp food industry in Australia, which is farm-raised. To confront such challenges, attempts have been made to selectively breed specific pathogen-resistant lines of thee species.[23]
P. monodon has been farmed throughout the world, including West Africa, Hawaii, Tahiti, and England.[12] For optimal growth, P. monodon is raised in waters between 28 and 33°C. Characteristically for the Penaeus genus, P. monodon has a natural ability to survive and grow in a wide range of salinity, though its optimal salinity is around 15-25 ppt.[24] While in a farm setting, the shrimp are typically fed a compound diet, which is produced in dried pellets.[17] By mixing the diet to have compound feeds and fresh feed, P. monodon was shown to have better reproductive performance.[17]
In 2010, Greenpeace added P. monodon to its seafood red list – "a list of fish that are commonly sold in supermarkets around the world, and which have a very high risk of being sourced from unsustainable fisheries". The reasons given by Greenpeace were "destruction of vast areas of mangroves in several countries, overfishing of juvenile shrimp from the wild to supply farms, and significant human-rights abuses".[25]
In an effort to understand whether DNA repair processes can protect crustaceans against infection, basic research was conducted to elucidate the repair mechanisms used by P. monodon.[26] Repair of DNA double-strand breaks was found to be predominantly carried out by accurate homologous recombinational repair. Another, less accurate process, microhomology-mediated end joining, is also used to repair such breaks.
{{cite journal}}: Cite journal requires |journal= (help) Penaeus monodon, commonly known as the giant tiger prawn, Asian tiger shrimp, black tiger shrimp, and other names, is a marine crustacean that is widely reared for food.
Tiger prawns displayed in a supermarket
