Blotched fantail ray
Encyclopedia
The blotched fantail ray (Taeniura meyeni) is a species
of stingray
in the family
Dasyatidae, found throughout the nearshore waters of the tropical Indo-Pacific
, as well as off islands in the eastern Pacific. It is a bottom-dwelling inhabitant of lagoon
s, estuaries, and reef
s, generally at a depth of 20–60 m (65.6–196.9 ft). Reaching 1.8 m (5.9 ft) across, this large ray is characterized by a thick, rounded pectoral fin disc covered by small tubercle
s on top, and a relatively short tail bearing a deep ventral fin fold. In addition, it has a variable but distinctive light and dark mottled pattern on its upper surface, and a black tail.
Generally nocturnal, the blotched fantail ray can be solitary or gregarious, and is an active predator of small, benthic molluscs, crustacean
s, and bony fishes. It is aplacental viviparous, with the embryo
s sustained by yolk, and later histotroph ("uterine milk") secreted by the mother; up to seven pups are born at a time. Although not aggressive, if provoked the blotched fantail ray will defend itself with its venom
ous tail spine, and it has been responsible for at least one fatality. It is valued by ecotourist
divers and recreational anglers
. This slow-reproducing species is threatened by commercial fishing
, both targeted and as bycatch
, and habitat degradation across much of its range. As a result, the International Union for Conservation of Nature (IUCN) has assessed it as Vulnerable
.
and Friedrich Gustav Jakob Henle
in their 1841 Systematische Beschreibung der Plagiostomen, based on two syntype
s collected from Mauritius
. However, this species is better known under the name Taeniura melanospila (or melanospilos), which was applied by Dutch ichthyologist Pieter Bleeker
to a juvenile specimen from Java
, in a 1953 volume of the scientific journal
Natuurkundig Tijdschrift voor Nederlandsch Indië.
Other common name
s for the blotched fantail ray include black spotted ray, black-blotched stingray, black-spotted stingray, fantail ray, fantail stingray, giant reef ray, round ribbontail ray, and speckled stingray. In Australia
, it is one of several species referred to as "bull ray
". A minority of authors place this species with the river stingrays in the family Potamotrygonidae
. Preliminary morphological
examination has suggested that the blotched fantail ray is more related to Dasyatis
and Indo-Pacific Himantura
than to the congeneric bluespotted ribbontail ray
(T. lymma), which is closer to the amphi-American Himantura (H. pacifica and H. schmardae) and the river stingrays.
region: it is found from KwaZulu-Natal
in South Africa
northward along the East Africa
n coast to the Red Sea
, including Madagascar
and the Mascarenes; from there, its range extends eastward through the Indian subcontinent
to Southeast Asia
and Micronesia
, occurring as far north as Korea
and southern Japan
, and as far south as Australia
, where it is found from at least Ningaloo Reef
off Western Australia
to Stradbroke Island
off Queensland
, including Lord Howe Island
. In the easternmost portion of its range, it has been reported from Cocos Island
and the Galápagos Islands
, with individuals possibly dispersing as far as Central America
.
Bottom-dwelling in nature, the blotched fantail ray is typically found close to shore at a depth of 20–60 m (65.6–196.9 ft), though it has been reported anywhere from the surf zone
to a depth of 439 m (1,440.3 ft). It favors sand or rubble bottoms in shallow lagoon
s or near coral
and rocky reef
s, and may also enter estuaries.
s. There is a short and broad curtain of skin between the oval nostril
s, with a finely fringed trailing margin. The mouth is wide and curved, with faint furrows at the corners. There is a row of seven papilla
e on the floor, with the outermost pair smaller and set apart from the others. There are 37–46 tooth rows in the upper jaw and 39–45 tooth rows in the lower jaw. The teeth are small with a deep groove across the crown, and are arranged in a dense quincunx
pattern into flattened surfaces.
The pelvic fins are small and narrow. The tail is relatively short, not exceeding the width of the disc, and bears one (rarely two) long, serrated stinging spine on the upper surface. The base of the tail is broad; past the spine the tail rapidly thins, and bears a deep ventral fin fold that runs to the tail tip. The upper surface of the disc and tail are roughened by a uniform covering of small, widely spaced granule
s. There is also a midline row of sharp tubercles on the back, with two shorter rows alongside. The first of these tubercles develop at a length of around 46 cm (18.1 in), over the "shoulders" and in the single midline row.
The dorsal coloration is light to dark gray, brown-gray, or purplish, becoming most intense towards the fin margins, with a highly variable pattern of irregular darker mottling and white speckles or streaks. The tail past the spine, including the fin fold, is uniformly black, while the underside is creamy white with darker fin margins and additional dots. Young rays are more plain in coloration than adults. One of the largest stingray species, the blotched fantail ray can grow to 1.8 m (5.9 ft) across, 3.3 m (10.8 ft) long, and 150 kg (330.7 lb) in weight.
or cobia
(Rachycentron canadum); these smaller fishes may feed on food stirred up by the ray's activities, or use the ray's body as cover for approaching their own prey. The blotched fantail ray hunts for bivalves, crab
s, shrimp
s, and small bony fishes on the bottom. When feeding, it adopts a characteristic posture in which it presses the margin of its disc against the bottom and takes in water through its spiracles, which it blows through its mouth to uncover prey buried in the sediment. This species may fall prey to larger fishes such as shark
s, and marine mammal
s. When threatened, it raises its tail over its back so that the spine faces forward, and waves it back and forth. Known parasites of this species include the monogenea
n Dasybatotrema spinosum, Dendromonocotyle pipinna, Neoentobdella garneri and N. taiwanensis, and the nematode
Echinocephalus overstreeti.
Little information is available on the life history of the blotched fantail ray. Like other stingrays, it is aplacental viviparous: the unborn embryo
s are initially sustained by yolk, which is later supplemented by histotroph ("uterine milk", containing protein
s, lipid
s, and mucus
) produced by the mother. Reproductive aggregations numbering in the hundreds have been observed at Cocos Island shortly after the onset of La Niña
, which brings cooler temperatures. During these periods a single female may be pursued by dozens of males. Females bear litters of up to seven pups, each measuring 33–35 cm (13–13.8 in) across and 67 cm (26.4 in) long. Off South Africa, birthing may take place in the summer. Males attain sexual maturity
at a disc width of 1–1.1 m (3.3–3.6 ft); the maturation size of females is unknown.
ous tail spine. This species has been responsible for at least one recorded fatality, of a diver who was stabbed while attempting to ride the ray. The blotched fantail ray is popular with ecotourist
divers because of its size and spectacular appearance. Although displayed in public aquarium
s, it is not hardy and 81 days is the longest one has been kept in captivity.
The International Union for Conservation of Nature (IUCN) has assessed the blotched fantail ray as Vulnerable
. It cannot withstand heavy fishing pressure due to its low reproductive rate, and there is widespread degradation of its coral reef habitat, including from agricultural runoff and destructive fishing practices such as blast fishing
. This species is caught by commercial
and fisheries
throughout its range, using line gear and trawls. One region where it is heavily pressured is in Indonesian waters, where it and other large rays are taken intentionally and otherwise by tangle netters
, longliners, and trawlers operating off Java, Bali
, New Guinea
, and Lombok
. All landed individuals are brought to market for human consumption.
Off South Africa, the blotched fantail ray is captured incidentally by prawn
trawlers on offshore banks, but is not utilized. Because of its size and strength, it is also prized by sport anglers, who usually release it unharmed. South Africa sets a recreational bag limit of one ray per species per person per day, and does not allow spearfishing
for this species. In Australian waters, this ray has been assessed as of Least Concern
. Although it is caught (and discarded) by prawn trawlers, this mortality has been reduced by the mandatory installation of Turtle Excluder Device
s (TEDs). Furthermore, a portion of its Australian range lies within the Great Barrier Reef Marine Park
. This species has also been listed under Least Concern in the Maldives
where, due to the tourist value of rays, the government has created protected marine reserves and banned the export of rays in 1995 and ray skins in 1996.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of stingray
Myliobatiformes
Myliobatiformes is one of the four orders of batoids, cartilaginous fishes related to sharks. They were formerly included in the order Rajiformes, but more recent phylogenetic studies have shown that the myliobatiforms are a monophyletic group, and that its more derived members evolved their...
in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Dasyatidae, found throughout the nearshore waters of the tropical Indo-Pacific
Indo-Pacific
The Indo-Pacific is a biogeographic region of the Earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia...
, as well as off islands in the eastern Pacific. It is a bottom-dwelling inhabitant of lagoon
Lagoon
A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...
s, estuaries, and reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
s, generally at a depth of 20–60 m (65.6–196.9 ft). Reaching 1.8 m (5.9 ft) across, this large ray is characterized by a thick, rounded pectoral fin disc covered by small tubercle
Tubercle
A tubercle is generally a wart-like projection, but it has slightly different meaning depending on which family of plants or animals it is used to refer to....
s on top, and a relatively short tail bearing a deep ventral fin fold. In addition, it has a variable but distinctive light and dark mottled pattern on its upper surface, and a black tail.
Generally nocturnal, the blotched fantail ray can be solitary or gregarious, and is an active predator of small, benthic molluscs, crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s, and bony fishes. It is aplacental viviparous, with the embryo
Embryo
An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination...
s sustained by yolk, and later histotroph ("uterine milk") secreted by the mother; up to seven pups are born at a time. Although not aggressive, if provoked the blotched fantail ray will defend itself with its venom
Venom
Venom is the general term referring to any variety of toxins used by certain types of animals that inject it into their victims by the means of a bite or a sting...
ous tail spine, and it has been responsible for at least one fatality. It is valued by ecotourist
Ecotourism
Ecotourism is a form of tourism visiting fragile, pristine, and usually protected areas, intended as a low impact and often small scale alternative to standard commercial tourism...
divers and recreational anglers
Recreational fishing
Recreational fishing, also called sport fishing, is fishing for pleasure or competition. It can be contrasted with commercial fishing, which is fishing for profit, or subsistence fishing, which is fishing for survival....
. This slow-reproducing species is threatened by commercial fishing
Commercial fishing
Commercial fishing is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice it as an industry must often pursue fish far into the ocean under adverse conditions...
, both targeted and as bycatch
Bycatch
The term “bycatch” is usually used for fish caught unintentionally in a fishery while intending to catch other fish. It may however also indicate untargeted catch in other forms of animal harvesting or collecting...
, and habitat degradation across much of its range. As a result, the International Union for Conservation of Nature (IUCN) has assessed it as Vulnerable
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
.
Taxonomy and phylogeny
As Taeniura meyeni, the blotched fantail ray was described by German biologists Johannes Peter MüllerJohannes Peter Müller
Johannes Peter Müller , was a German physiologist, comparative anatomist, and ichthyologist not only known for his discoveries but also for his ability to synthesize knowledge.-Early years and education:...
and Friedrich Gustav Jakob Henle
Friedrich Gustav Jakob Henle
Friedrich Gustav Jakob Henle was a German physician, pathologist and anatomist. He is credited with the discovery of the loop of Henle in the kidney. His essay "On Miasma and Contagia" was an early argument for the germ theory of disease...
in their 1841 Systematische Beschreibung der Plagiostomen, based on two syntype
Syntype
In biological nomenclature, a syntype is a term used to indicate a specimen with a special status.In zoological nomenclature, a syntype is defined as "Each specimen of a type series from which neither a holotype nor a lectotype has been designated [Arts. 72.1.2, 73.2, 74]. The syntypes...
s collected from Mauritius
Mauritius
Mauritius , officially the Republic of Mauritius is an island nation off the southeast coast of the African continent in the southwest Indian Ocean, about east of Madagascar...
. However, this species is better known under the name Taeniura melanospila (or melanospilos), which was applied by Dutch ichthyologist Pieter Bleeker
Pieter Bleeker
Pieter Bleeker was a Dutch medical doctor and ichthyologist, famous for his work on the fishes of East Asia – Atlas Ichthyologique des Orientales Neerlandaises – which was published 1862–1877....
to a juvenile specimen from Java
Java
Java is an island of Indonesia. With a population of 135 million , it is the world's most populous island, and one of the most densely populated regions in the world. It is home to 60% of Indonesia's population. The Indonesian capital city, Jakarta, is in west Java...
, in a 1953 volume of the scientific journal
Scientific journal
In academic publishing, a scientific journal is a periodical publication intended to further the progress of science, usually by reporting new research. There are thousands of scientific journals in publication, and many more have been published at various points in the past...
Natuurkundig Tijdschrift voor Nederlandsch Indië.
Other common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
s for the blotched fantail ray include black spotted ray, black-blotched stingray, black-spotted stingray, fantail ray, fantail stingray, giant reef ray, round ribbontail ray, and speckled stingray. In Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, it is one of several species referred to as "bull ray
Bull ray (disambiguation)
Various stingray species are at times called bull rays. These include:* Bull rays * Bull ray * Blotched fantail ray * Black stingray or thorntail stingray...
". A minority of authors place this species with the river stingrays in the family Potamotrygonidae
Potamotrygonidae
River stingrays are Neotropical freshwater fishes of the Potamotrygonidae family .They are native to northern, central and eastern South America, living in rivers that drain into the Caribbean, and into the Atlantic as far south as the Río de la Plata in Argentina...
. Preliminary morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
examination has suggested that the blotched fantail ray is more related to Dasyatis
Dasyatis
Dasyatis is a genus of stingray. The members of the genus Neotrygon were formerly included in Dasyatis.-Species:...
and Indo-Pacific Himantura
Himantura
Himantura is a genus of stingray in the family Dasyatidae, commonly known as the whiprays. They are distinguished from other stingrays by a long, slender tail without tail folds. Himantura species are very morphologically diverse and the genus may be polyphyletic...
than to the congeneric bluespotted ribbontail ray
Bluespotted ribbontail ray
The bluespotted ribbontail ray is a species of stingray in the family Dasyatidae. Found from the intertidal zone to a depth of , this species is common throughout the tropical Indian and western Pacific Oceans in nearshore, coral reef-associated habitats...
(T. lymma), which is closer to the amphi-American Himantura (H. pacifica and H. schmardae) and the river stingrays.
Distribution and habitat
The blotched fantail ray has a wide distribution in the Indo-PacificIndo-Pacific
The Indo-Pacific is a biogeographic region of the Earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia...
region: it is found from KwaZulu-Natal
KwaZulu-Natal
KwaZulu-Natal is a province of South Africa. Prior to 1994, the territory now known as KwaZulu-Natal was made up of the province of Natal and the homeland of KwaZulu....
in South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
northward along the East Africa
East Africa
East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
n coast to the Red Sea
Red Sea
The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez...
, including Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
and the Mascarenes; from there, its range extends eastward through the Indian subcontinent
Indian subcontinent
The Indian subcontinent, also Indian Subcontinent, Indo-Pak Subcontinent or South Asian Subcontinent is a region of the Asian continent on the Indian tectonic plate from the Hindu Kush or Hindu Koh, Himalayas and including the Kuen Lun and Karakoram ranges, forming a land mass which extends...
to Southeast Asia
Southeast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
and Micronesia
Micronesia
Micronesia is a subregion of Oceania, comprising thousands of small islands in the western Pacific Ocean. It is distinct from Melanesia to the south, and Polynesia to the east. The Philippines lie to the west, and Indonesia to the southwest....
, occurring as far north as Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...
and southern Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, and as far south as Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, where it is found from at least Ningaloo Reef
Ningaloo Reef
Ningaloo Reef is a fringing coral reef located off the west coast of Australia, approximately 1200 km north of Perth. The reef is 260 km long and is Australia's largest fringing coral reef and the only large reef positioned very close to a landmass....
off Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
to Stradbroke Island
Stradbroke Island
Stradbroke Island, also known as Minjerribah, was a large sand island that formed much of the eastern side of Moreton Bay near Brisbane, Queensland until the late 19th century...
off Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
, including Lord Howe Island
Lord Howe Island
Lord Howe Island is an irregularly crescent-shaped volcanic remnant in the Tasman Sea between Australia and New Zealand, directly east of mainland Port Macquarie, and about from Norfolk Island. The island is about 11 km long and between 2.8 km and 0.6 km wide with an area of...
. In the easternmost portion of its range, it has been reported from Cocos Island
Cocos Island
Cocos Island is an uninhabited island located off the shore of Costa Rica . It constitutes the 11th district of Puntarenas Canton of the province of Puntarenas. It is one of the National Parks of Costa Rica...
and the Galápagos Islands
Galápagos Islands
The Galápagos Islands are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, west of continental Ecuador, of which they are a part.The Galápagos Islands and its surrounding waters form an Ecuadorian province, a national park, and a...
, with individuals possibly dispersing as far as Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
.
Bottom-dwelling in nature, the blotched fantail ray is typically found close to shore at a depth of 20–60 m (65.6–196.9 ft), though it has been reported anywhere from the surf zone
Surf zone
As ocean surface waves come closer to shore they break, forming the foamy, bubbly surface we call surf. The region of breaking waves defines the surf zone. After breaking in the surf zone, the waves continue to move in, and they run up onto the sloping front of the beach, forming an uprush of...
to a depth of 439 m (1,440.3 ft). It favors sand or rubble bottoms in shallow lagoon
Lagoon
A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...
s or near coral
Coral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
and rocky reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
s, and may also enter estuaries.
Description
The blotched fantail ray has a thick pectoral fin disc wider than it is long, with a smoothly rounded outer margin. The eyes are of medium size and are followed by larger spiracleSpiracle
Spiracles are openings on the surface of some animals that usually lead to respiratory systems.-Vertebrates:The spiracle is a small hole behind each eye that opens to the mouth in some fishes. In the primitive jawless fish the first gill opening immediately behind the mouth is essentially similar...
s. There is a short and broad curtain of skin between the oval nostril
Nostril
A nostril is one of the two channels of the nose, from the point where they bifurcate to the external opening. In birds and mammals, they contain branched bones or cartilages called turbinates, whose function is to warm air on inhalation and remove moisture on exhalation...
s, with a finely fringed trailing margin. The mouth is wide and curved, with faint furrows at the corners. There is a row of seven papilla
Papilla (fish mouth structure)
The papilla, in certain kinds of fish, particularly rays, sharks, and catfish, are small lumps of dermal tissue found in the mouth, where they are "distributed uniformly on the tongue, palate, and pharynx"...
e on the floor, with the outermost pair smaller and set apart from the others. There are 37–46 tooth rows in the upper jaw and 39–45 tooth rows in the lower jaw. The teeth are small with a deep groove across the crown, and are arranged in a dense quincunx
Quincunx
A quincunx is a geometric pattern consisting of five points arranged in a cross, that is five coplanar points, four of them forming a square or rectangle and a fifth at its center...
pattern into flattened surfaces.
The pelvic fins are small and narrow. The tail is relatively short, not exceeding the width of the disc, and bears one (rarely two) long, serrated stinging spine on the upper surface. The base of the tail is broad; past the spine the tail rapidly thins, and bears a deep ventral fin fold that runs to the tail tip. The upper surface of the disc and tail are roughened by a uniform covering of small, widely spaced granule
Granule
Granule is a generic term used for a small particle or grain. The generic term is employed in a variety of specific contexts.* Granule , visible structures in the photosphere of the Sun arising from activity in the Sun's convective zone...
s. There is also a midline row of sharp tubercles on the back, with two shorter rows alongside. The first of these tubercles develop at a length of around 46 cm (18.1 in), over the "shoulders" and in the single midline row.
The dorsal coloration is light to dark gray, brown-gray, or purplish, becoming most intense towards the fin margins, with a highly variable pattern of irregular darker mottling and white speckles or streaks. The tail past the spine, including the fin fold, is uniformly black, while the underside is creamy white with darker fin margins and additional dots. Young rays are more plain in coloration than adults. One of the largest stingray species, the blotched fantail ray can grow to 1.8 m (5.9 ft) across, 3.3 m (10.8 ft) long, and 150 kg (330.7 lb) in weight.
Biology and ecology
The blotched fantail ray has nocturnal habits and rests motionless for much of the day, often near vertical structures, in caves, or under ledges. It may be solitary, or form small to large groups. This ray is frequently shadowed by one or more jacksCarangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
or cobia
Cobia
Cobia —also known as black kingfish, black salmon, ling, lemonfish, crabeaters, aruan tasek, etc.—are perciform marine fish, the sole representative of their family, the Rachycentridae.-Description:...
(Rachycentron canadum); these smaller fishes may feed on food stirred up by the ray's activities, or use the ray's body as cover for approaching their own prey. The blotched fantail ray hunts for bivalves, crab
Crab
True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...
s, shrimp
Shrimp
Shrimp are swimming, decapod crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Adult shrimp are filter feeding benthic animals living close to the bottom. They can live in schools and can swim rapidly backwards. Shrimp are an important...
s, and small bony fishes on the bottom. When feeding, it adopts a characteristic posture in which it presses the margin of its disc against the bottom and takes in water through its spiracles, which it blows through its mouth to uncover prey buried in the sediment. This species may fall prey to larger fishes such as shark
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
s, and marine mammal
Marine mammal
Marine mammals, which include seals, whales, dolphins, and walruses, form a diverse group of 128 species that rely on the ocean for their existence. They do not represent a distinct biological grouping, but rather are unified by their reliance on the marine environment for feeding. The level of...
s. When threatened, it raises its tail over its back so that the spine faces forward, and waves it back and forth. Known parasites of this species include the monogenea
Monogenea
Monogenea are a group of largely ectoparasitic members of the flatworm phylum Platyhelminthes, class Monogenea.-Characteristics:Monogenea are very small parasitic flatworms mainly found on skin or gills of fish....
n Dasybatotrema spinosum, Dendromonocotyle pipinna, Neoentobdella garneri and N. taiwanensis, and the nematode
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...
Echinocephalus overstreeti.
Little information is available on the life history of the blotched fantail ray. Like other stingrays, it is aplacental viviparous: the unborn embryo
Embryo
An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination...
s are initially sustained by yolk, which is later supplemented by histotroph ("uterine milk", containing protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
s, lipid
Lipid
Lipids constitute a broad group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins , monoglycerides, diglycerides, triglycerides, phospholipids, and others...
s, and mucus
Mucus
In vertebrates, mucus is a slippery secretion produced by, and covering, mucous membranes. Mucous fluid is typically produced from mucous cells found in mucous glands. Mucous cells secrete products that are rich in glycoproteins and water. Mucous fluid may also originate from mixed glands, which...
) produced by the mother. Reproductive aggregations numbering in the hundreds have been observed at Cocos Island shortly after the onset of La Niña
La Niña
La Niña is a coupled ocean-atmosphere phenomenon that is the counterpart of El Niño as part of the broader El Niño-Southern Oscillation climate pattern. During a period of La Niña, the sea surface temperature across the equatorial Eastern Central Pacific Ocean will be lower than normal by 3–5 °C...
, which brings cooler temperatures. During these periods a single female may be pursued by dozens of males. Females bear litters of up to seven pups, each measuring 33–35 cm (13–13.8 in) across and 67 cm (26.4 in) long. Off South Africa, birthing may take place in the summer. Males attain sexual maturity
Sexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
at a disc width of 1–1.1 m (3.3–3.6 ft); the maturation size of females is unknown.
Human interactions
The blotched fantail ray is not aggressive, and has been known to approach and investigate divers. However, if harassed it can inflict a severe wound with its venomVenom
Venom is the general term referring to any variety of toxins used by certain types of animals that inject it into their victims by the means of a bite or a sting...
ous tail spine. This species has been responsible for at least one recorded fatality, of a diver who was stabbed while attempting to ride the ray. The blotched fantail ray is popular with ecotourist
Ecotourism
Ecotourism is a form of tourism visiting fragile, pristine, and usually protected areas, intended as a low impact and often small scale alternative to standard commercial tourism...
divers because of its size and spectacular appearance. Although displayed in public aquarium
Public aquarium
A public aquarium is the aquatic counterpart of a zoo, housing living aquatic species for viewing. Most public aquariums feature tanks larger than those kept by home aquarists, as well as smaller tanks. Since the first public aquariums were built in the mid-19th century, they have become popular...
s, it is not hardy and 81 days is the longest one has been kept in captivity.
The International Union for Conservation of Nature (IUCN) has assessed the blotched fantail ray as Vulnerable
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
. It cannot withstand heavy fishing pressure due to its low reproductive rate, and there is widespread degradation of its coral reef habitat, including from agricultural runoff and destructive fishing practices such as blast fishing
Blast fishing
Blast fishing or dynamite fishing is the practice of using explosives to stun or kill schools of fish for easy collection. This often illegal practice can be extremely destructive to the surrounding ecosystem, as the explosion often destroys the underlying habitat that supports the fish...
. This species is caught by commercial
Commercial fishing
Commercial fishing is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice it as an industry must often pursue fish far into the ocean under adverse conditions...
and fisheries
Recreational fishing
Recreational fishing, also called sport fishing, is fishing for pleasure or competition. It can be contrasted with commercial fishing, which is fishing for profit, or subsistence fishing, which is fishing for survival....
throughout its range, using line gear and trawls. One region where it is heavily pressured is in Indonesian waters, where it and other large rays are taken intentionally and otherwise by tangle netters
Tangle net
Similar to a gillnet, the tangle net, or tooth net, is a type of nylon fishing net. Left in the water for no more than two days, and allowing bycatch to be released alive, this net is considered to be less harmful that other nets. The tangle net is used in the Philippines by commercial fishermen,...
, longliners, and trawlers operating off Java, Bali
Bali
Bali is an Indonesian island located in the westernmost end of the Lesser Sunda Islands, lying between Java to the west and Lombok to the east...
, New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, and Lombok
Lombok
Lombok is an island in West Nusa Tenggara province, Indonesia. It forms part of the chain of the Lesser Sunda Islands, with the Lombok Strait separating it from Bali to the west and the Alas Strait between it and Sumbawa to the east...
. All landed individuals are brought to market for human consumption.
Off South Africa, the blotched fantail ray is captured incidentally by prawn
Prawn
Prawns are decapod crustaceans of the sub-order Dendrobranchiata. There are 540 extant species, in seven families, and a fossil record extending back to the Devonian...
trawlers on offshore banks, but is not utilized. Because of its size and strength, it is also prized by sport anglers, who usually release it unharmed. South Africa sets a recreational bag limit of one ray per species per person per day, and does not allow spearfishing
Spearfishing
Spearfishing is an ancient method of fishing that has been used throughout the world for millennia. Early civilizations were familiar with the custom of spearing fish from rivers and streams using sharpened sticks....
for this species. In Australian waters, this ray has been assessed as of Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
. Although it is caught (and discarded) by prawn trawlers, this mortality has been reduced by the mandatory installation of Turtle Excluder Device
Turtle excluder device
A turtle excluder device or TED is a specialized device that allows a captured sea turtle to escape when caught in a fisherman's net.In particular, sea turtles can be caught when bottom trawling is used by the commercial shrimp fishing industry. In order to catch shrimp, a fine meshed trawl net is...
s (TEDs). Furthermore, a portion of its Australian range lies within the Great Barrier Reef Marine Park
Great Barrier Reef Marine Park
The Great Barrier Reef Marine Park protects a large part of Australia's Great Barrier Reef from damaging activities. Fishing and the removal of artefacts or...
. This species has also been listed under Least Concern in the Maldives
Maldives
The Maldives , , officially Republic of Maldives , also referred to as the Maldive Islands, is an island nation in the Indian Ocean formed by a double chain of twenty-six atolls oriented north-south off India's Lakshadweep islands, between Minicoy Island and...
where, due to the tourist value of rays, the government has created protected marine reserves and banned the export of rays in 1995 and ray skins in 1996.
External links
- Taeniura meyeni, Blotched fantail ray at FishBase
- Taeniura meyeni (Black-blotched Stingray, Black-spotted Stingray, Blotched Fantail Ray, Fantail Stingray, Giant Reef Ray, Round Ribbontail Ray, Speckled Stingray) at IUCN Red List
- Biological Profiles: Blotched Fantail Ray at Florida Museum of Natural History Ichthyology Department