Dark shyshark
Encyclopedia
The dark shyshark or pretty Happy (Haploblepharus pictus) is a species
of catshark
, family
Scyliorhinidae, endemic to the temperate
waters off southern Namibia
and western South Africa
. It is benthic
in nature and inhabits shallow, inshore waters and favors rocky reef
s and kelp forest
s. Growing to 60 cm (23.6 in) long, this small, stocky shark has a wide, flattened head with a rounded snout and a large flap of skin extending from before the nostrils to the mouth. Its dorsal coloration is extremely variable and may feature black-edged orange to blackish saddles and/or white spots on a light brown to nearly black background.
When threatened, the dark shyshark curls into a ring with its tail covering its eyes, hence the name "shyshark". It preys mainly on small crustacean
s, bony fishes, and molluscs. Reproduction is oviparous and proceeds throughout the year. Females lay two egg cases at a time, which hatch after 6–10 months. This harmless species is of little commercial significance
due to its small size. It is frequently caught by recreational fishers
and persecuted as a pest. The International Union for Conservation of Nature (IUCN) has listed the dark shyshark under Least Concern
, as it is common and does not appear to be substantially threatened by fishing or habitat degradation.
German physicians and biologists Johannes Peter Müller
and Friedrich Gustav Jakob Henle
originally described the dark shyshark in their 1838–41 Systematische Beschreibung der Plagiostomen, based on five specimens caught off the Cape of Good Hope
and deposited in the Rijksmuseum van Natuurlijke Historie
in Leiden, The Netherlands. Because of the shark's ornate coloration, they gave it the specific epithet pictum from the Latin
for "painted". Originally placed in the now-obsolete genus Scyllium, subsequent authors moved this species to the genus Haploblepharus
, coined by American zoologist Samuel Garman in 1913.
The dark shyshark was often regarded to be the same as the puffadder shyshark
(H. edwardsii) until 1975, with the publication of A.J. Bass, Jeanette D'Aubrey, and Nat Kistnasamy's review of southern African sharks. It continues to be confused for the other three shyshark species because of its extremely variable coloration. The common name
"pretty Happy" ("Happy" refers to the genus name Haploblepharus) was recently introduced to the public as an easily remembered alternative to the colloquial names "shyshark" and "doughnut", which can apply to several species and have confounded research efforts. Brett Human's 2006 phylogenetic analysis
, based on three mitochondrial DNA
gene
s, found that the dark shyshark and the brown shyshark
(H. fuscus) are sister species, and that the two make up the more derived
clade
within the genus.
in southern Namibia
to east of the Storms River
mouth in the Eastern Cape Province of South Africa
. It is abundant, particularly west of Cape Agulhas
. This species is a bottom-dweller found close inshore, from the intertidal zone
to a depth of 35 m (114.8 ft). It prefers rocky reefs and kelp forest
s, but also presumably traverses sandy flats in between patches of more suitable habitat
. As this shark is not known to travel long distances, there is likely subpopulation differentiation across parts of its range.
Reaching no more than 60 cm (23.6 in) long, the dark shyshark differs from other shysharks in that it is slender-bodied when juvenile and stocky-bodied when adult. Its head is short, wide, and flattened, with a bluntly rounded snout and very large nostrils. The anterior rims of the nostrils bear greatly enlarged lobes of skin, which are fused into a single flap that reaches the mouth; the flap conceals the nasal excurrent openings and a pair of grooves that run between them and the mouth. The large, horizontally oval eyes are equipped with rudimentary nictitating membrane
s (protective third eyelids), and have strong ridges beneath. The mouth is short but wide and bears furrows at the corners extending onto both jaws. There are 45–83 upper and 47–75 lower tooth rows; each tooth has a long central cusp flanked by a pair of smaller cusplets. The five pairs of gill slit
s are located fairly high on the body.
The two dorsal fin
s are of nearly equal size and placed far back on the body, with the first originating over the latter third of the pelvic fin bases and the second over the latter half of the anal fin base. The pectoral and pelvic fins are broad and rounded; the males have stout claspers. The pelvic and anal fins are about as large as the dorsal fins. The broad caudal fin comprises about a fifth of the total body length and has a strong notch near the tip of the upper lobe and an indistinct lower lobe. The skin is thick and covered by well-calcified
arrowhead-shaped dermal denticles. The coloration of the dark shyshark is highly variable, and particular individuals can resemble any of the other shyshark species. The background color ranges from light brown to reddish to grayish to almost black above, transitioning abruptly to white or cream below, sometimes with dark blotches beneath the paired fins. There may be 6–8 orange, brown, or blackish variably shaped saddles along the back and tail, edged more or less obviously in black. There may also be white spots within or within and between the saddles.
predator whose main food sources are, in descending order of importance, small benthic crustacean
s, bony fishes, and molluscs. Larger sharks consume proportionately more crustaceans. Polychaete worms and echinoderm
s are also taken on occasion, and algae
may be swallowed incidentally. This species is preyed upon by the broadnose sevengill shark
(Notorynchus cepedianus), and potentially also other large fishes and marine mammal
s. When threatened, it adopts a characteristic defense posture in which it curls into a ring with its tail over its eyes; this behavior likely makes the shark harder to swallow and is the origin of the common names "shyshark" and "doughnut". In captivity, the whelks
Burnupena papyracea
and B. lagenaria
have been documented piercing the egg cases of this species and extracting the yolk. A known parasite of the dark shyshark is the trypanosome
Trypanosoma haploblephari, which infests the blood
.
Like other members of its genus, the dark shyshark is oviparous; adult females have a single functional ovary
and two functional oviduct
s. There appears to be no distinct breeding season
and reproduction occurs year-round. Females produce mature eggs two at a time, one per oviduct. The eggs are enclosed in purse-shaped capsules measuring 5.5 cm (2.2 in) long and 2.5 cm (0.984251968503937 in) across; each capsule is plain amber to dark brown in color and bears thin, coiled tendrils at the four corners. In one observation of an egg that hatched after 104 days, the developing embryo
had external gill filaments until it was 50 days old, and completely absorbed its yolk sac
shortly before hatching. Eggs in nature typically hatch in 6–10 months, with the newly hatched shark measuring 10–12 cm (3.9–4.7 in) long. Both sexes grow at approximately the same rate, reaching sexual maturity
at around 15 years of age. Mature males and females range from 40–57 cm (15.7–22.4 in) and 36–60 cm (14.2–23.6 in) long respectively. The maximum lifespan is 25 years.
casting from the shore, who regard the shark as a pest and often kill it. It may also be caught by subsistence fishers
and in lobster trap
s and bottom trawls, though not in substantial quantities. This shark occasionally finds its way into the aquarium trade
, though there is no direct fishing for this purpose. As the dark shyshark remains common and does not seem heavily threatened by human activity, it has been assessed as Least Concern
by the International Union for Conservation of Nature (IUCN). Its small range does raise concerns that an increase in regional fishing pressure or habitat degradation could impact the entire population.
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 catshark
Catshark
Catsharks are ground sharks of the family Scyliorhinidae, with over 150 known species. While they are generally known as catsharks, many species are commonly called dogfish....
, 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...
Scyliorhinidae, endemic to the temperate
Temperate
In geography, temperate or tepid latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally relatively moderate, rather than extreme hot or cold...
waters off southern Namibia
Namibia
Namibia, officially the Republic of Namibia , is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Angola and Zambia to the north, Botswana to the east and South Africa to the south and east. It gained independence from South Africa on 21 March...
and western 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...
. It is benthic
Benthic zone
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos. They generally live in close relationship with the substrate bottom; many such...
in nature and inhabits shallow, inshore waters and favors rocky reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
s and kelp forest
Kelp forest
Kelp forests are underwater areas with a high density of kelp. They are recognized as one of the most productive and dynamic ecosystems on Earth. Smaller areas of anchored kelp are called kelp beds....
s. Growing to 60 cm (23.6 in) long, this small, stocky shark has a wide, flattened head with a rounded snout and a large flap of skin extending from before the nostrils to the mouth. Its dorsal coloration is extremely variable and may feature black-edged orange to blackish saddles and/or white spots on a light brown to nearly black background.
When threatened, the dark shyshark curls into a ring with its tail covering its eyes, hence the name "shyshark". It preys mainly on small 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, bony fishes, and molluscs. Reproduction is oviparous and proceeds throughout the year. Females lay two egg cases at a time, which hatch after 6–10 months. This harmless species is of little commercial significance
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...
due to its small size. It is frequently caught by recreational fishers
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....
and persecuted as a pest. The International Union for Conservation of Nature (IUCN) has listed the dark shyshark under 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...
, as it is common and does not appear to be substantially threatened by fishing or habitat degradation.
Taxonomy and phylogeny
Johannes 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...
originally described the dark shyshark in their 1838–41 Systematische Beschreibung der Plagiostomen, based on five specimens caught off the Cape of Good Hope
Cape of Good Hope
The Cape of Good Hope is a rocky headland on the Atlantic coast of the Cape Peninsula, South Africa.There is a misconception that the Cape of Good Hope is the southern tip of Africa, because it was once believed to be the dividing point between the Atlantic and Indian Oceans. In fact, the...
and deposited in the Rijksmuseum van Natuurlijke Historie
Rijksmuseum van Natuurlijke Historie
The Rijksmuseum van Natuurlijke Historie was a museum in Leiden, The Netherlands. It was founded in 1820 by Royal Decree, formed from a merger of several existing collections. This happened at the instigation of Coenraad Jacob Temminck, who saw the museum primarily as a research institute...
in Leiden, The Netherlands. Because of the shark's ornate coloration, they gave it the specific epithet pictum from the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "painted". Originally placed in the now-obsolete genus Scyllium, subsequent authors moved this species to the genus Haploblepharus
Haploblepharus
Haploblepharus is a genus of catshark, family Scyliorhinidae, containing four species of shysharks. Their common name comes from a distinctive defensive behavior in which the shark curls into a circle and covers its eyes with its tail. The genus is endemic to southern Africa, inhabiting shallow...
, coined by American zoologist Samuel Garman in 1913.
The dark shyshark was often regarded to be the same as the puffadder shyshark
Puffadder shyshark
The puffadder shyshark or happy Eddie is a species of catshark, family Scyliorhinidae, endemic to the temperate waters off South Africa. This common shark is found on or near the bottom in sandy or rocky habitats, from the intertidal zone to a depth of . Typically reaching in length, the...
(H. edwardsii) until 1975, with the publication of A.J. Bass, Jeanette D'Aubrey, and Nat Kistnasamy's review of southern African sharks. It continues to be confused for the other three shyshark species because of its extremely variable coloration. The 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...
"pretty Happy" ("Happy" refers to the genus name Haploblepharus) was recently introduced to the public as an easily remembered alternative to the colloquial names "shyshark" and "doughnut", which can apply to several species and have confounded research efforts. Brett Human's 2006 phylogenetic analysis
Molecular phylogeny
Molecular phylogenetics is the analysis of hereditary molecular differences, mainly in DNA sequences, to gain information on an organism's evolutionary relationships. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree...
, based on three mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...
gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s, found that the dark shyshark and the brown shyshark
Brown shyshark
The brown shyshark or plain happy, is a species of catshark, family Scyliorhinidae, endemic to the shallow, coastal waters of South Africa from west of Cape Agulhas to KwaZulu-Natal. This benthic species is usually found over sandy or rocky bottoms...
(H. fuscus) are sister species, and that the two make up the more derived
Derived
In phylogenetics, a derived trait is a trait that is present in an organism, but was absent in the last common ancestor of the group being considered. This may also refer to structures that are not present in an organism, but were present in its ancestors, i.e. traits that have undergone secondary...
clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
within the genus.
Distribution and habitat
The range of the dark shyshark is restricted to the coastal waters of southern Africa, from north of LüderitzLüderitz
Lüderitz is a harbour town in south-west Namibia, lying on one of the least hospitable coasts in Africa. It is a port developed around Robert Harbour and Shark Island.- Overview :...
in southern Namibia
Namibia
Namibia, officially the Republic of Namibia , is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Angola and Zambia to the north, Botswana to the east and South Africa to the south and east. It gained independence from South Africa on 21 March...
to east of the Storms River
Storms River
Storms River is a river in the Eastern Cape province of South Africa. The river mouth is located in the Tsitsikamma National Park.- See also :* Tsitsikamma National Park* Paul Sauer Bridge* List of rivers of South Africa...
mouth in the Eastern Cape Province of 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...
. It is abundant, particularly west of Cape Agulhas
Cape Agulhas
Cape Agulhas is a rocky headland in the Western Cape, South Africa. It is the geographic southern tip of Africa and the official dividing point between the Atlantic and Indian oceans...
. This species is a bottom-dweller found close inshore, from the intertidal zone
Intertidal zone
The intertidal zone is the area that is above water at low tide and under water at high tide . This area can include many different types of habitats, with many types of animals like starfish, sea urchins, and some species of coral...
to a depth of 35 m (114.8 ft). It prefers rocky reefs and kelp forest
Kelp forest
Kelp forests are underwater areas with a high density of kelp. They are recognized as one of the most productive and dynamic ecosystems on Earth. Smaller areas of anchored kelp are called kelp beds....
s, but also presumably traverses sandy flats in between patches of more suitable habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
. As this shark is not known to travel long distances, there is likely subpopulation differentiation across parts of its range.
Description
Nictitating membrane
The nictitating membrane is a transparent or translucent third eyelid present in some animals that can be drawn across the eye for protection and to moisten it while maintaining visibility. Some reptiles, birds, and sharks have a full nictitating membrane; in many mammals, there is a small...
s (protective third eyelids), and have strong ridges beneath. The mouth is short but wide and bears furrows at the corners extending onto both jaws. There are 45–83 upper and 47–75 lower tooth rows; each tooth has a long central cusp flanked by a pair of smaller cusplets. The five pairs of gill slit
Gill slit
Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of Cartilaginous fish such as sharks, rays, sawfish, and guitarfish. Most of these have five pairs, but a few species have 6 or 7 pairs...
s are located fairly high on the body.
The two dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
s are of nearly equal size and placed far back on the body, with the first originating over the latter third of the pelvic fin bases and the second over the latter half of the anal fin base. The pectoral and pelvic fins are broad and rounded; the males have stout claspers. The pelvic and anal fins are about as large as the dorsal fins. The broad caudal fin comprises about a fifth of the total body length and has a strong notch near the tip of the upper lobe and an indistinct lower lobe. The skin is thick and covered by well-calcified
Calcification
Calcification is the process in which calcium salts build up in soft tissue, causing it to harden. Calcifications may be classified on whether there is mineral balance or not, and the location of the calcification.-Causes:...
arrowhead-shaped dermal denticles. The coloration of the dark shyshark is highly variable, and particular individuals can resemble any of the other shyshark species. The background color ranges from light brown to reddish to grayish to almost black above, transitioning abruptly to white or cream below, sometimes with dark blotches beneath the paired fins. There may be 6–8 orange, brown, or blackish variably shaped saddles along the back and tail, edged more or less obviously in black. There may also be white spots within or within and between the saddles.
Biology and ecology
The dark shyshark is a generalistGeneralist and specialist species
A generalist species is able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources . A specialist species can only thrive in a narrow range of environmental conditions or has a limited diet. Most organisms do not all fit neatly into either...
predator whose main food sources are, in descending order of importance, small benthic 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, bony fishes, and molluscs. Larger sharks consume proportionately more crustaceans. Polychaete worms and echinoderm
Echinoderm
Echinoderms are a phylum of marine animals. Echinoderms are found at every ocean depth, from the intertidal zone to the abyssal zone....
s are also taken on occasion, and algae
Algae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
may be swallowed incidentally. This species is preyed upon by the broadnose sevengill shark
Broadnose sevengill shark
The broadnose sevengill shark is the only extant member of the genus Notorynchus, in the family Hexanchidae. It is recognizable because of its seven gill slits, while most shark species have five gill slits, with the exception of the members of the order Hexanchiformes and the sixgill sawshark.The...
(Notorynchus cepedianus), and potentially also other large fishes 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 adopts a characteristic defense posture in which it curls into a ring with its tail over its eyes; this behavior likely makes the shark harder to swallow and is the origin of the common names "shyshark" and "doughnut". In captivity, the whelks
Buccinidae
Buccinidae is a very large and diverse taxonomic family of large sea snails, often known as whelks or true whelks.True whelks are mostly marine gastropod mollusks in the clade Neogastropoda...
Burnupena papyracea
Burnupena papyracea
Burnupena papyracea, common name the papery burnupena, is a species of sea snail, a marine gastropod mollusk in the family Buccinidae, the true whelks....
and B. lagenaria
Burnupena lagenaria
Burnupena lagenaria is a species of sea snail, a marine gastropod mollusk in the family Buccinidae, the true whelks....
have been documented piercing the egg cases of this species and extracting the yolk. A known parasite of the dark shyshark is the trypanosome
Trypanosoma
Trypanosoma is a genus of kinetoplastids , a monophyletic group of unicellular parasitic flagellate protozoa. The name is derived from the Greek trypano and soma because of their corkscrew-like motion. All trypanosomes are heteroxenous and are transmitted via a vector...
Trypanosoma haploblephari, which infests the blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
.
Ovary
The ovary is an ovum-producing reproductive organ, often found in pairs as part of the vertebrate female reproductive system. Ovaries in anatomically female individuals are analogous to testes in anatomically male individuals, in that they are both gonads and endocrine glands.-Human anatomy:Ovaries...
and two functional oviduct
Oviduct
In non-mammalian vertebrates, the passageway from the ovaries to the outside of the body is known as the oviduct. The eggs travel along the oviduct. These eggs will either be fertilized by sperm to become a zygote, or will degenerate in the body...
s. There appears to be no distinct breeding season
Breeding season
The breeding season is the most suitable season, usually with favourable conditions and abundant food and water, for breeding among some wild animals and birds . Species with a breeding season have naturally evolved to have sexual intercourse during a certain time of year in order to achieve the...
and reproduction occurs year-round. Females produce mature eggs two at a time, one per oviduct. The eggs are enclosed in purse-shaped capsules measuring 5.5 cm (2.2 in) long and 2.5 cm (0.984251968503937 in) across; each capsule is plain amber to dark brown in color and bears thin, coiled tendrils at the four corners. In one observation of an egg that hatched after 104 days, the developing 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...
had external gill filaments until it was 50 days old, and completely absorbed its yolk sac
Yolk sac
The yolk sac is a membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals...
shortly before hatching. Eggs in nature typically hatch in 6–10 months, with the newly hatched shark measuring 10–12 cm (3.9–4.7 in) long. Both sexes grow at approximately the same rate, reaching 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 around 15 years of age. Mature males and females range from 40–57 cm (15.7–22.4 in) and 36–60 cm (14.2–23.6 in) long respectively. The maximum lifespan is 25 years.
Human interactions
The dark shyshark poses no danger to humans and is too small to be of commercial importance. Many are hooked by sport fishersRecreational 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....
casting from the shore, who regard the shark as a pest and often kill it. It may also be caught by subsistence fishers
Artisan fishing
Artisan fishing is a term used to describe small scale low-technology commercial or subsistence fishing practices. The term particularly applies to coastal or island ethnic groups using traditional techniques such as rod and tackle, arrows and harpoons, throw nets and drag nets, and traditional...
and in lobster trap
Lobster trap
Not to be confused with Lobster-tailed potA lobster trap or lobster pot is a portable trap that traps lobsters or crayfish and is used in lobster fishing. A lobster trap can hold several lobsters. Lobster traps are constructed of wire and wood. An opening permits the lobster to enter a tunnel of...
s and bottom trawls, though not in substantial quantities. This shark occasionally finds its way into the aquarium trade
Fishkeeping
Fishkeeping is a popular hobby concerned with keeping fish in a home aquarium or garden pond. There is also a fishkeeping industry, as a branch of agriculture.-Types of fishkeeping systems:...
, though there is no direct fishing for this purpose. As the dark shyshark remains common and does not seem heavily threatened by human activity, it has been assessed as 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...
by the International Union for Conservation of Nature (IUCN). Its small range does raise concerns that an increase in regional fishing pressure or habitat degradation could impact the entire population.