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Catshark

Catsharks are small to medium-sized sharks belonging to the family Scyliorhinidae within the order Carcharhiniformes, distinguished by their elongated, cat-like eyes equipped with a nictitating membrane and a bottom-dwelling lifestyle.^[1] This is the largest family of sharks, encompassing around 160 species across 17 genera, with many species rarely exceeding 1 meter in length, though the maximum recorded size reaches about 1.6 meters.^[1]^[2] They inhabit a wide range of benthic environments in temperate and tropical seas worldwide, from shallow coastal waters and intertidal zones to depths greater than 2,000 meters on continental and insular slopes.^[1]^[3] Physically, catsharks feature a fusiform body covered in placoid scales, five gill slits (with the fifth positioned over the pectoral fin base), two small spineless dorsal fins located posteriorly on the body, and an anal fin.^[3] Their mouths are positioned forward but not fully under the snout, and most lack prominent nasal barbels, though exceptions exist in genera like Poroderma.^[4] These sharks are generally slow-moving and non-migratory, with many exhibiting nocturnal behavior; some species, such as swell sharks in the genus Cephaloscyllium, can inflate their stomachs with air or water as a defense mechanism.^[1] Biologically, catsharks are predominantly oviparous, with about 90% of species laying eggs encased in tough, rectangular capsules often equipped with tendrils for attachment to substrates like algae or rocks, facilitating internal fertilization prior to deposition.^[1] A smaller number are ovoviviparous, retaining eggs internally until hatching. Their diet consists mainly of small fishes, crustaceans, mollusks, and other invertebrates, with feeding strategies ranging from bottom foraging to ambush predation.^[1]^[3] While harmless to humans, many catsharks hold ecological importance as predators in marine food webs and some economic value in fisheries, though certain species face threats from overfishing and habitat degradation, leading to vulnerable or near-threatened statuses for several taxa.^[1]

Taxonomy and classification

Families and genera

The term "catshark" collectively refers to small sharks in the order Carcharhiniformes assigned to five main families, encompassing approximately 160 species characterized by their elongated cat-like eyes and bottom-dwelling habits. As of 2024, updates include the addition of new species like Apristurus ovicorrugatus in Pentanchidae.^[5] The family Scyliorhinidae, known as true catsharks, includes the majority of shallow-water species and is now restricted to three genera with about 36 species following recent revisions: Cephaloscyllium (swellsharks, 18 species), Poroderma (2 species), and Scyliorhinus (16 species, including the nursehound S. stellaris). Pentanchidae, the deepwater catsharks, comprises around 90 species across 10 genera, such as Apristurus (ghost catsharks, approximately 39 species), Galeus (sawtail catsharks, 18 species), and Parmaturus (11 species); this family was historically subsumed within Scyliorhinidae but elevated based on distinct morphological traits like the absence of supraorbital crests. Atelomycteridae, the coloured catsharks, features about 12 species in two subfamilies and genera including Atelomycterus (6 species) and Schroederichthys (4 species); it was revalidated and split from Scyliorhinidae using molecular and morphological evidence to reflect its unique ectodermal pit distribution and coloration patterns. Pseudotriakidae, the false catsharks, contains 5 species in three genera: Pseudotriakis, Gollum, and Planonasus, distinguished by continuous labial furrows and deep-sea adaptations.^[6] Proscylliidae, the finback catsharks, includes 7 species in three genera: Ctenacis, Eridacnis, and Proscyllium, noted for their slender bodies and rudimentary nictitating membranes.^[7] A 2022 phylogenetic study utilizing 143 morphological characters and NADH2 gene sequences confirmed the monophyly of these families and most genera, driving updates like the redefinition of Apristurus and the addition of subfamilies within Pentanchidae (Halaelurinae and Galeinae), enhancing understanding of catshark diversity.

Etymology and nomenclature

The common name "catshark" originates from a linguistic evolution in post-medieval European vernaculars, where the Latin term catulus (meaning "puppy" or "young dog") was misinterpreted or adapted into words evoking "cat" in Romance languages, such as French chat (cat) and Italian gatto (cat).^[8] This shift appeared in early ichthyological texts, including Guillaume Rondelet's 1554 description as Chat rochier and Ippolito Salviani's 1558 Pescie Gatto, reflecting a misapplication of canine descriptors to these sharks' small size and bottom-dwelling habits rather than their ocular features.^[8] Although popularly attributed to the sharks' large, reflective, cat-like eyes, historical analysis confirms the name's canine roots, with English usage emerging in the 18th century alongside Linnaean taxonomy.^[8] In nomenclature, catsharks were initially classified by Carl Linnaeus in his 1758 Systema Naturae under the order Selachii (a broad grouping for cartilaginous fishes) and the genus Squalus, with species like Squalus canicula (now the lesser spotted catshark, Scyliorhinus canicula) named using binomial descriptors emphasizing diminutive canine traits (canicula from Latin for "little dog").^[9] The family Scyliorhinidae, established by Theodore Gill in 1862, derives its name from the genus Scyliorhinus (Blainville, 1816), combining Greek skýlion (small dog or whelp, alluding to dogfish-like qualities) and rhī́nē (rasp or file, referring to the rough, denticle-covered skin), though some interpretations link it to rhīs (nose) for the tapered snout.^[8]^[3] Modern binomial nomenclature applies this system across genera, exemplified by Scyliorhinus canicula for the widespread northeast Atlantic species.^[10] Common names vary regionally, with many European populations of Scyliorhinus species referred to as "dogfish" due to overlapping historical descriptors, leading to frequent confusion with true dogfishes of the family Squalidae (e.g., spurdogs like Squalus acanthias).^[11] In fisheries contexts, terms like "ground shark" or "rock salmon" (a euphemism for S. canicula in UK markets) further obscure distinctions, as catsharks inhabit benthic grounds but differ taxonomically from other ground sharks.^[12] Synonymy issues stem from early misclassifications, such as Linnaeus's Squalus catulus (1758), a junior synonym of Scyliorhinus canicula arising from redundant canine epithets.^[8] In deepwater taxa, genera like Apristurus (family Pentanchidae, formerly lumped with Scyliorhinidae) were historically termed "black catsharks" based on uniform dark coloration, but recent phylogenetic revisions specify them by depth ranges (e.g., 400–2000 m) to resolve ambiguities with shallower Scyliorhinus species.^[13]^[14]

Phylogenetic relationships

The families collectively referred to as catsharks belong to the order Carcharhiniformes, commonly known as ground sharks, where they occupy a basal position relative to other families such as Triakidae (houndsharks).^[15] This order is characterized by shared morphological traits including a nictitating membrane and a caudal fin with a ventral lobe longer than the dorsal lobe. Phylogenetic analyses indicate that the crown group of Carcharhiniformes originated in the Early Jurassic, with divergence times estimated at approximately 192 million years ago (95% highest posterior density interval: 175–207 Ma), aligning with the Jurassic period's onset around 201–145 Ma.^[16] Molecular evidence from studies utilizing mitochondrial DNA (mtDNA) and nuclear genes has elucidated key splits within Carcharhiniformes, including the separation of Pentanchidae (deep-sea catsharks) from Scyliorhinidae. A 2012 analysis of NADH dehydrogenase 2 (ND2) mtDNA sequences across diverse elasmobranchs supported the basal positioning of scyliorhinids and highlighted paraphyletic patterns in related families, reinforcing earlier morphological frameworks.^[17] Complementary work by Maisey (2012) integrated paleontological data with molecular phylogenies, emphasizing the evolutionary divergence of catshark lineages from triakids around 150–190 million years ago during the Jurassic. Shirai's 1992 cladistic analysis of skeletal and muscular characters further established the monophyly of Carcharhiniformes while positioning Scyliorhinidae as a foundational clade, with subsequent molecular validations confirming these interrelationships.^[18] In broader phylogenetic trees of Carcharhiniformes, Proscylliidae (finback catsharks) occupies the most basal position, followed by Scyliorhinidae, with Triakidae and more derived families like Carcharhinidae branching later.^[19] The monophyly of Scyliorhinidae has been affirmed by genomic analyses in the 2020s, including mitogenomic studies that resolve internal relationships using complete mitochondrial genomes and nuclear markers, demonstrating cohesive genetic clustering distinct from neighboring families.^[20] These trees underscore catsharks' primitive traits, such as egg-laying reproduction, as plesiomorphic within the order. The fossil record of catshark-like forms dates to the Late Jurassic, with articulated skeletons from Germany representing early Carcharhiniformes around 150 million years ago, though definitive Scyliorhinidae fossils appear in the Cretaceous (~100 Ma).^[21] Notable examples include Paracarcharias from Late Cretaceous deposits of South Carolina, USA, featuring dental morphologies akin to modern catsharks, providing evidence of their persistence through the Mesozoic.^[22] This record aligns with molecular divergence estimates, illustrating a gradual diversification from Jurassic ancestors.^[22]

Physical characteristics

Morphology and anatomy

Catsharks in the family Scyliorhinidae exhibit an elongated, slender fusiform body shape that tapers at both ends, often slightly depressed, facilitating efficient movement through aquatic environments. The body features two dorsal fins positioned posteriorly, typically with the first dorsal fin originating over or behind the pelvic fin bases, and both lacking spines, a characteristic distinguishing them from many other shark families. An anal fin is present, contributing to propulsion, while the caudal fin is asymmetrical with a long upper lobe and a shorter lower lobe featuring a subterminal notch.^[1]^[23] The head of catsharks is relatively narrow to moderately broad, with a snout that varies from short and bluntly rounded to moderately long and pointed, often lacking lateral skin flaps. Eyes are large and cat-like, positioned dorsolaterally as horizontal ovals, equipped with a rudimentary nictitating membrane for protection but without subocular pockets. Sensory adaptations include nasal barbels (prominent in some genera, such as Poroderma) and, in many species, nasoral grooves connecting the nostrils to the mouth, enhancing chemosensation; spiracles, moderately large and positioned below the eyes, aid in water intake for respiration. Additional sensory structures encompass ampullae of Lorenzini for detecting electric fields and a lateral line system for mechanoreception, with olfactory rosettes providing a well-developed sense of smell.^[1]^[24]^[23] The skeletal system is entirely cartilaginous, hardened by calcified deposits, providing flexibility and lightness compared to bony structures in other fish, which supports agile swimming and reduces overall body weight. Muscular arrangements include well-developed trunk and appendicular musculature, with specific units in the cephalic region integrating feeding and sensory functions, though detailed muscular differentiation varies across development.^[25]^[26] Respiratory adaptations feature five pairs of gill slits on the sides of the head, increasing in size posteriorly in some genera, without extension onto the dorsal surface or filter screens. Spiracles supplement gill ventilation by allowing water to enter directly, particularly useful in low-oxygen benthic habitats, while buccopharyngeal denticles line the mouth and pharyngeal regions, offering protection against abrasion during feeding. Some species, such as those in deeper waters, exhibit enlarged branchial regions to cope with hypoxic conditions.^[1]^[25]^[23]

Size variations and growth

Catsharks display considerable variation in adult size across species, with most attaining total lengths (TL) of 20–100 cm. Representative examples include the small-spotted catshark (Scyliorhinus canicula), which reaches a maximum of approximately 100 cm TL, and the blackmouth catshark (Galeus melastomus), typically growing to 70–80 cm TL.^[27]^[28] At the extremes, deepwater species such as certain Apristurus max out at 30–50 cm TL, while larger shallow-water species like the nursehound (Scyliorhinus stellaris) can exceed 170 cm TL.^[29]^[30] Growth in catsharks is generally slow, with annual increments of 0.5–2 cm in later stages, as indicated by von Bertalanffy growth parameters (e.g., growth coefficient K ≈ 0.20 year⁻¹ for S. canicula).^[31] Sexual maturity occurs at 30–60 cm TL, varying by species; for instance, S. canicula males mature at about 43 cm TL and females at 45 cm TL, often after 6–7 years.^[32] Longevity ranges from 10 to 30 years, with tag-recapture studies confirming lifespans exceeding 12 years in S. canicula and up to 20+ years in related species through vertebral ageing validation.^[27]^[33] Sexual dimorphism is prevalent, with females typically larger than males at maturity and exhibiting extended growth post-maturity.^[34] Growth curves, estimated via counts of annual vertebral bands, reveal sex-specific trajectories; in S. canicula, females surpass males in asymptotic length, reaching 5–10 cm greater maximum sizes.^[35]^[36] Factors such as habitat depth and latitude influence size attainment, with deepwater species consistently smaller (e.g., Bythaelurus reaching a maximum of 30–76 cm TL) compared to shallower-water species.^[29] Latitudinal effects are evident in species like S. canicula, where Mediterranean populations achieve larger sizes than those at higher latitudes, potentially due to temperature-driven growth differences.^[27]

Coloration and camouflage

Catsharks in the family Scyliorhinidae exhibit a diverse array of coloration patterns that primarily serve adaptive purposes in their respective habitats, often featuring mottled browns, grays, or darker tones interspersed with spots, saddles, or bars. For instance, the lesser spotted catshark (Scyliorhinus canicula) displays a light grayish-brown dorsal surface adorned with numerous small, dark spots and subtle saddles, contrasting with a pale ventral side, which aids in blending with sandy or rocky seabeds.^[27]^[37] Similarly, species in the genus Atelomycterus, such as the coral catshark (A. marmoratus), possess more vivid patterns including bold black spots outlined in white against a brownish background, providing disruptive camouflage among coral structures.^[38]^[39] These patterns vary across genera, with deeper-water forms like the filetail catshark (Parmaturus xaniurus) showing uniform gray-brown dorsally without prominent markings, suited to dimly lit slopes.^[40] A key camouflage mechanism in catsharks is countershading, where the dorsal surface is darker to match the shadowed underwater environment from above, while the lighter ventral side mimics the brighter downwelling light, reducing visibility to predators in benthic or midwater settings.^[41] In addition, many species incorporate biofluorescence, particularly in deeper waters, where skin pigments absorb blue light and re-emit it as green fluorescence that enhances their mottled patterns. For example, in the chain catshark (Scyliorhinus retifer) and swellshark (Cephaloscyllium ventriosum), this green glow intensifies the contrast of spots and saddles under low-light conditions, potentially aiding concealment by matching ambient light spectra.^[42]^[43] This fluorescent enhancement is chemically derived from brominated tryptophan metabolites in the skin, which not only produce the glow but also contribute to the overall pigmentation.^[43] Ontogenetic changes in coloration are common among scyliorhinid catsharks, with juveniles typically displaying more vivid and contrasting patterns that fade or become more subdued as adults mature, reflecting shifts in habitat use or predation pressures. In many species, early life stages feature bolder spots or saddles for crypsis in nursery areas, which homogenize with growth to suit broader adult ranges.^[44] These transformations underscore the adaptive flexibility of catshark pigmentation, aligning visual traits with developmental ecology across the family.

Distribution and habitat

Global range

Catsharks, belonging to the family Scyliorhinidae, exhibit a cosmopolitan distribution across temperate and tropical oceans worldwide, inhabiting the Atlantic, Indian, and Pacific basins from shallow coastal waters to deep-sea environments.^[3] This broad range spans multiple biogeographic provinces, with species documented on continental shelves and slopes across all major ocean systems except the polar Arctic and Antarctic regions in significant numbers.^[1] Recent taxonomic revisions have reduced the family to 37 species across 3 genera (as of November 2025), unevenly distributed, with higher diversity in the Indo-Pacific compared to the Atlantic.^[45]^[46] Many genera show regional biases, such as Scyliorhinus, which predominates in the Northern Hemisphere's temperate waters of the eastern Atlantic and Mediterranean Sea, where species like the small-spotted catshark (Scyliorhinus canicula) range from Norway to Senegal.^[47] Other genera extend into the western Atlantic and eastern Pacific. Endemism is particularly pronounced in isolated or deep-sea regions, contributing to the family's species diversity. High endemism rates underscore the role of oceanographic barriers in speciation.^[48] Most catshark species are sedentary, with limited large-scale migrations, though some coastal forms exhibit seasonal movements tied to temperature or prey availability. In the Mediterranean, for instance, populations of Scyliorhinus show restricted dispersal influenced by historical glacial refugia, maintaining genetic structure over small scales.^[49]

Habitat preferences

Catsharks, members of the family Scyliorhinidae, predominantly exhibit benthic and demersal lifestyles, residing on or near the seafloor in a variety of coastal and shelf ecosystems. They favor substrates such as rocky reefs, seagrass beds, and soft sediments including sand, mud, and gravel, which provide ample cover and foraging opportunities. For instance, the small-spotted catshark (Scyliorhinus canicula) thrives in shallow coastal waters up to 400 m deep, commonly over sandy or muddy bottoms in the northeastern Atlantic.^[50]^[1] These sharks often associate with structural features for shelter, hiding in crevices, caves, or among algae during inactive periods. Species in the genus Cephaloscyllium, such as the swellshark (Cephaloscyllium ventriosum), actively inflate their bodies with water or air to wedge tightly into rocky crevices or caves, enhancing security against predators. This behavior underscores their preference for complex reef habitats that offer microhabitats for resting and egg deposition.^[51]^[1] Catsharks generally require moderate marine conditions, with salinity levels around 30–35 ppt and temperatures ranging from 5–25°C, varying by species and geographic distribution. Temperate species like S. canicula prefer 14–19°C and salinities near 35 ppt in coastal environments.^[52] They also co-occur with other benthic fauna in shared dens or overlapping habitats, such as with the octopus Eledone cirrhosa and various crustaceans, where resource partitioning allows coexistence in reef and sedimentary areas.^[53]

Depth and environmental adaptations

Catsharks exhibit a wide range of depth distributions, with species primarily inhabiting shallower coastal waters from 0 to 200 meters, while some extend to mesopelagic depths up to 1,500 meters or more.^[1]^[54]^[55] This vertical stratification reflects evolutionary adaptations to pressure gradients, where the flexible, cartilaginous skeleton of catsharks provides inherent compressibility, allowing tissues to withstand hydrostatic pressures up to 450 atmospheres without structural collapse, unlike rigid bony skeletons in teleost fishes.^[56]^[57] Physiological mechanisms enable catsharks to thrive in these environments, including elevated urea concentrations in their blood and tissues for osmoregulation, which maintains cellular hydration under high salinity and pressure conditions common in deep waters. Deep-dwelling species possess enlarged livers rich in low-density squalene oils, comprising up to 20% of body weight, which provide neutral buoyancy and reduce energy expenditure on locomotion in the absence of a swim bladder.^[58] Additionally, hemoglobin variants in these sharks exhibit high oxygen affinity, facilitating efficient oxygen uptake in low-oxygen deep-sea waters, with some species demonstrating exceptional hypoxia tolerance comparable to the most resilient marine fishes.^[59]^[60] Catsharks also display resilience to environmental stressors such as temperature fluctuations and hypoxia, critical for survival in variable deep-sea conditions. Recent deep-sea research, including 2023 expeditions identifying new species in Australian waters at depths over 1,000 meters, has highlighted specialized sensory adaptations in these catsharks for navigating extreme environments, though direct associations with hydrothermal vents remain under investigation in ongoing studies.^[61]

Biology and ecology

Diet and feeding habits

Catsharks are carnivorous predators with diets dominated by benthic invertebrates and small fishes, reflecting their opportunistic foraging in coastal and shelf environments. The small-spotted catshark (Scyliorhinus canicula), a common shallow-water species, primarily consumes crustaceans such as shrimp and crabs, alongside small demersal fishes and occasional mollusks, with stomach content analyses revealing crustaceans comprising up to 38% of the diet by numerical abundance and fishes around 53%.^[62] In deeper-water species like the blackmouth catshark (Galeus melastomus), decapod crustaceans remain a key component (46% by index of relative importance), but cephalopods, euphausiids, and mesopelagic fishes contribute significantly as secondary prey.^[63] Feeding strategies among catsharks emphasize ambush predation, where individuals often lie in wait on the seafloor during the day, relying on camouflage before striking at passing prey, particularly during nocturnal activity peaks.^[64] They capture prey using a combination of biting and suction feeding, facilitated by jaw protrusion that enhances intraoral pressure and allows rapid enclosure of targets within the gape.^[65] This modulation of feeding kinematics enables effective predation on mobile invertebrates and evasive fishes, with smaller catsharks exhibiting greater reliance on suction for elusive prey.^[66] As mid-level predators, catsharks occupy trophic levels typically ranging from 3.5 to 4.0, positioning them as mesopredators that regulate lower trophic tiers while facing predation from larger elasmobranchs.^[37] Dietary composition shifts with ontogeny, season, and habitat depth; juveniles and smaller individuals preferentially target invertebrates like mysids and euphausiids, transitioning to more fishes as they grow, while seasonal variations reflect prey availability.^[67] Stomach content studies highlight depth-related differences, with shallow-water species deriving over 70% of their diet from invertebrates in some populations, compared to deeper conspecifics or related taxa incorporating more pelagic fishes (up to 50% or higher).^[68] These patterns underscore the trophic plasticity of catsharks, enabling adaptation to varying environmental conditions.^[69]

Reproduction and development

Catsharks (family Scyliorhinidae) are predominantly oviparous, with females laying eggs encased in leathery capsules known as mermaid's purses, which feature tendrils for attachment to substrates such as algae, rocks, or coral to prevent drifting.^[70] These egg cases are typically deposited one per oviduct, though some species exhibit multiple oviparity, retaining several in each uterus simultaneously. Internal fertilization occurs via the males' claspers, paired appendages on the pelvic fins that deliver sperm during mating, a process observed year-round in many tropical and subtropical species but with seasonal peaks in temperate ones, such as winter and summer breeding activity in the blackmouth catshark (Galeus melastomus).^[1]^[71]^[72] Embryonic development within the egg case is direct, with the embryo absorbing the yolk sac completely before hatching, resulting in fully formed, independent juveniles without a prolonged yolk-sac larval stage. Incubation periods vary by species and environmental conditions, typically ranging from 4 to 12 months; for example, the small-spotted catshark (Scyliorhinus canicula) hatches after 5-6 months at temperate temperatures, while the larger nursehound (Scyliorhinus stellaris) requires 9-12 months.^[73]^[74] Hatchlings emerge at lengths of 8-15 cm, depending on the species, and are immediately capable of predatory feeding and dispersal.^[75] Fecundity in catsharks generally ranges from 10 to 50 eggs per female annually, increasing with female size and species; the small-spotted catshark produces 29-62 eggs per year, while larger congeners like the nursehound may lay more due to greater ovarian capacity.^[73]^[76] Egg production is often continuous but modulated by environmental cues, contributing to the family's relatively high reproductive output among oviparous elasmobranchs.^[72] Catsharks in the family Scyliorhinidae exhibit predominantly nocturnal or crepuscular activity patterns, with increased movement and foraging occurring at night while they rest during the day. For instance, the small-spotted catshark (Scyliorhinus canicula) shows higher activity levels and larger activity spaces at night (mean speed of 79 ± 41 m/h and activity space of 0.13 ± 0.04 km²) compared to daytime (activity space of 0.09 ± 0.02 km²), often remaining inactive at midday possibly through buccal pumping while sheltered in crevices or caves.^[77] Similarly, the swellshark (Cephaloscyllium ventriosum) rests motionless in rocky dens during daylight hours and becomes active at night to hunt, aligning with its ambush predation strategy.^[78] Locomotion in catsharks relies on a combination of axial undulation for steady propulsion and pectoral fin movements for precise maneuvering and stability. In species like the small-spotted catshark, steady swimming involves anguilliform body undulation, with pectoral fins angling to generate lift and control pitch during cruising or turns. This fin-based maneuvering allows for agile navigation over complex benthic habitats. In the swellshark genus (Cephaloscyllium), slow, weak swimming is supplemented by pectoral fin adjustments, enabling the species to hover or position itself effectively for prey ambushes.^[42] Catsharks are generally solitary, showing no evidence of complex social hierarchies, though juveniles may aggregate when familiar with one another and adults occasionally form loose groups in areas of high prey density. Adult small-spotted catsharks, for example, display high site fidelity and residency without grouping tendencies, with females exhibiting stronger philopatry than males.^[77] In contrast, juvenile S. canicula form non-random aggregations driven by familiarity, increasing social attraction indices but not necessarily group sizes, suggesting a role in reducing predation risk during early life stages. Swellsharks (C. ventriosum) are typically solitary but may congregate in caves or high-prey reef areas, without observed dominance structures.^[42] Antipredator behaviors in catsharks emphasize camouflage, immobility, and physical defenses rather than aggression. Many species, including the small-spotted catshark, employ a freeze response when detecting threats, remaining motionless to blend with the substrate and avoid detection by larger predators like other sharks. In the swellshark genus (Cephaloscyllium), individuals curve their bodies into a U-shape and gulp water or air into the stomach to inflate up to double their size, making them difficult to swallow and deterring predators. These responses to threats, such as approaching larger elasmobranchs, highlight adaptations suited to their benthic lifestyle.

Conservation and human interactions

Threats and vulnerabilities

Catsharks, belonging to the family Scyliorhinidae, face significant threats from bycatch in commercial fisheries, particularly demersal trawls and gillnets targeting demersal fish species. In the Northeast Atlantic, species such as the small-spotted catshark (Scyliorhinus canicula) are commonly captured as incidental catch, comprising a notable proportion of discards due to their abundance in coastal and shelf habitats.^[79] Although many individuals exhibit high post-release survivorship, the cumulative mortality from repeated captures contributes to population stress, especially for smaller-bodied species with limited escape capabilities.^[80] Habitat degradation poses another major vulnerability, primarily through bottom trawling that disrupts benthic environments like rocky reefs and seagrass beds essential for catshark shelter and egg deposition. This fishing method physically damages substrate structures, reducing available nursery areas and increasing exposure to predators.^[81] Additionally, coastal development and pollution, including chemical contaminants, adversely affect egg case integrity and embryonic development, as catsharks are oviparous and rely on protective capsules for reproduction.^[82] Climate change exacerbates these risks, with ocean warming and acidification altering physiological processes in catsharks. Experimental studies on the small-spotted catshark demonstrate that combined warming and acidification impair embryonic growth, hatching success, and early juvenile metabolism, potentially reducing recruitment rates.^[83] Furthermore, rising temperatures may shift species distributions poleward, disrupting established ranges and increasing overlap with intensified fishing grounds.^[84] Overfishing represents a direct threat, as some catshark species are targeted or retained for fishmeal, bait, and aquarium trade, compounded by their k-selected life history traits including slow growth and low fecundity. In regions like the Mediterranean, intense exploitation has led to regional declines, classifying certain populations as vulnerable despite global assessments often rating the family as least concern overall.^[79] This vulnerability is heightened by their limited mobility and dependence on stable habitats, making recovery challenging without reduced fishing pressure.^[85]

Conservation measures

Conservation efforts for catsharks are guided primarily by assessments from the International Union for Conservation of Nature (IUCN), which classify many species in the family Scyliorhinidae as Data Deficient due to insufficient data on population trends, distribution, and threats. For instance, the small-spotted catshark (Scyliorhinus canicula), one of the most abundant and widely distributed species, is rated Least Concern, reflecting its resilience across coastal waters of the Northeast Atlantic and Mediterranean. In contrast, deepwater species such as the yellowspotted catshark (Scyliorhinus capensis) are assessed as Near Threatened (assessed 01 August 2019), underscoring their vulnerability to habitat disturbance and bycatch in deeper oceanic zones.^[86] Regulatory measures have been enacted to mitigate impacts on catshark populations, particularly in regions with intensive fishing. The European Union introduced a comprehensive deep-sea fisheries regulation in 2016, prohibiting bottom trawling below 800 meters in EU waters to safeguard vulnerable marine ecosystems, including habitats frequented by deepwater catsharks.^[87] In 2022, the European Commission closed 87 areas to all bottom-contact fishing gears, representing about 7% of EU waters and further protecting deep-sea habitats used by catsharks.^[87] While no catshark species are currently listed under the Convention on International Trade in Endangered Species (CITES), broader protections for elasmobranchs, such as those for rare deep-sea taxa in families like Atelomycteridae, are advocated through regional agreements to prevent unregulated trade. These policies aim to reduce incidental capture, a key threat briefly noted in vulnerability assessments, by enforcing gear restrictions and closed seasons in high-risk areas.^[88] Research initiatives play a crucial role in informing conservation strategies for catsharks. The International Council for the Exploration of the Sea (ICES) Working Group on Elasmobranch Fishes (WGEF) conducted population monitoring in 2023, including tagging studies to track movements and abundance of species like S. canicula, revealing limited migration patterns that support targeted protection efforts.^[89] Additionally, aquaculture programs for conservation breeding have been established, such as those at the Cologne Zoo Aquarium, where coral catsharks (Atelomycterus marmoratus) have been successfully reared since 2010 to bolster captive populations and genetic diversity for potential reintroduction.^[90] Success stories demonstrate the efficacy of protected areas in catshark recovery. In the Mediterranean, the establishment of marine protected areas (MPAs) post-2010, such as those under the Barcelona Convention, has led to observed increases in elasmobranch densities, including catsharks, by restricting fishing activities and allowing habitat regeneration.^[88] These MPAs have contributed to localized population rebounds, providing models for expanding conservation networks across catshark ranges.^[91]

Role in fisheries and aquaria

Catsharks are harvested in commercial fisheries primarily in Europe and Asia for their meat and skins, contributing to local and regional markets. In European waters, species such as the small-spotted catshark (Scyliorhinus canicula) hold moderate commercial importance, with catches targeted for human consumption and processed products. ^[27] ^[1] In Asia, Indo-Pacific catsharks like the bamboo catshark (Chiloscyllium punctatum) are caught for similar uses, often as part of broader elasmobranch fisheries. ^[92] The European Union represents a significant market for shark and dogfish meat, including catsharks, with trade focused on intra-regional consumption. ^[93] Several catshark species are popular in public aquaria due to their small size, bottom-dwelling habits, and relative ease of care, making them suitable for educational displays. The bamboo catshark is frequently featured in touch pools at facilities such as the Aquarium of the Pacific and the New England Aquarium, where visitors can interact with these docile animals to learn about shark biology. ^[94] ^[95] Similarly, the small-spotted catshark is commonly displayed in aquarium tanks across Europe and North America for its adaptability to captivity. ^[96] Captive breeding programs for elasmobranchs, including catsharks like coral and small-spotted species, are implemented in aquaria to support sustainable exhibits and reduce reliance on wild captures, employing reproductive technologies such as artificial insemination. ^[97] ^[98] Sustainable practices in catshark fisheries emphasize low-impact methods and eco-labeling to ensure long-term viability. Programs like the Marine Stewardship Council certify shark fisheries that minimize bycatch and adhere to science-based quotas, applying to some catshark-harvesting operations in Europe as part of broader elasmobranch management. ^[99] These initiatives promote alternatives to overexploitation, such as selective gear and stock assessments, while aquarium breeding reduces demand for wild specimens. ^[99] Catsharks hold cultural significance in coastal communities, serving as bait in targeted fisheries and contributing to traditional shark-derived products. In some Asian regions, shark species including catsharks are incorporated into folk medicines for purported health benefits, though scientific validation is limited. ^[100] Ecotourism opportunities allow divers to observe catsharks in their natural habitats, fostering public appreciation and supporting conservation awareness without direct handling. ^[96]

References

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Scyliorhinidae (Cat sharks) | INFORMATION - Animal Diversity Web
The family Scyliorhinidae is the largest shark family, with at least 15 genera and over 100 species. Their common name, catsharks, likely derives from their ...
[2]
FAMILY Details for Scyliorhinidae - Cat sharks - FishBase
Nov 29, 2012 · Family Scyliorhinidae - Cat sharks ; Order, : Carcharhiniformes ; Class, : Elasmobranchii ; No. in FishBase, : Genera : 4 | Species : 39 ...
[3]
Family SCYLIORHINIDAE - Fishes of Australia
Summary: Similar to the collared carpetsharks (Family Parascyllidae) in general shape but differ in having a more posteriorly placed mouth that is never totally ...
[4]
FAMILY Details for Pseudotriakidae - False catsharks - FishBase
Nov 29, 2012 · Family Pseudotriakidae - False catsharks ; Order, : Carcharhiniformes ; Class, : Elasmobranchii ; No. in FishBase, : Genera : 3 | Species : 5 ...
[5]
FAMILY Details for Proscylliidae - Finback catsharks - FishBase
Nov 29, 2012 · Carcharhiniformes · Proscylliidae. Class, : Elasmobranchii. No. in FishBase, : Genera : 3 | Species : 7 Eschmeyer's Catalog of Fishes.
[6]
[PDF] Family SCYLIORHINIDAE - The ETYFish Project
The deepwater catshark (Pentanchidae) genera Bythaelurus,. Cephalurus and Halaelurus are based on the Greek noun aílouros (αἴλουρος), meaning cat. Despite its ...
[7]
Scyliorhinus canicula (Linnaeus, 1758) - WoRMS
Jan 15, 2008 · Neoselachii (Subclass); Selachii (Infraclass); Galeomorphi ... Classification Scyliorhinus canicula (Linnaeus, 1758) [details]. Diet ...
[8]
Scyliorhinus canicula, Lesser spotted dogfish - FishBase
Most common catshark in coastal waters of Europe (Ref. 32804). Inhabits continental shelves and uppermost slopes. Found on sandy, coralline, algal, gravel or ...
[9]
Dogfish or Catshark? - ReefQuest Centre for Shark Research
Adding to the confusion, some catsharks (especially those of the genus Scyliorhinus) are often referred to as "dogfishes". But once one has learned their ...
[10]
Have scientists have changed the name of the Lesser-spotted ...
Have scientists have changed the name of the Lesser-spotted dogfish to Small-spotted catshark? ... When early naturalists such as Carl von Linné (aka Linnaeus) ...
[11]
Combined phylogeny and new classification of catsharks ...
The main changes in nomenclature and classification are the revised definition and scope of Scyliorhinidae, Apristurus and Pentanchus and the revalidation of ...<|separator|>
[12]
Apristurus melanoasper, Black roughscale catshark - FishBase
Etymology: Apristurus: a-, Latin privative, i.e., without; pristis, from pristes (Gr.), sawyer (but here meaning saw); oura (Gr.), tail, referring to absence of ...
[13]
Phylogeny of sharks of the family Triakidae (Carcharhiniformes) and ...
We present a study of inter- and intra-familial relationships of the carcharhiniform shark family Triakidae aimed at testing existing hypotheses of ...
[14]
Combining palaeontological and neontological data shows ... - Nature
Dec 19, 2022 · The divergence time estimates indicate an origin of the crown Carcharhiniformes in the Early Jurassic (191.7 Ma, 95% HPD = 174.7–207.1 Ma) ...
[15]
A DNA Sequence–Based Approach To the Identification of Shark ...
Jun 21, 2012 · A comprehensive survey of DNA sequences derived from the mitochondrial NADH2 gene was conducted for elasmobranchs collected from around the world.
[16]
What is an 'elasmobranch'? The impact of palaeontology in ...
The impact of palaeontology in understanding elasmobranch phylogeny and evolution. J. G. Maisey,. Corresponding Author. J. G. Maisey. Division ...
[17]
Complete mitochondrial genome and the phylogenetic position of ...
In this study, the complete mitogenome of Proscyllium habereri (Carcharhiniformes: Proscylliidae) is first determined. It is 16,708 bp in length, ...
[18]
(PDF) Combined phylogeny and new classification of catsharks ...
The main changes in nomenclature and classification are the revised definition and scope of Scyliorhinidae, Apristurus and Pentanchus and the revalidation of ...
[19]
A catshark (Neoselachii, Carcharhiniformes, Scyliorhinidae) from the ...
Aug 5, 2025 · The new taxon is known from a single articulated skeleton having the skull, the trunk and all of the fins preserved. The position of the first ...Missing: Paleo | Show results with:Paleo
[20]
Full article: A new genus and species of extinct ground shark ...
The new carcharhiniform is characterized by a unique combination of dental morphologies, indicating close architectural resemblance to the family Scyliorhinidae ...
[21]
[PDF] FAO species catalogue. Vol. 4. Sharks of the world. An annotated ...
Diagnostic Features: Head with short, anterior nasal flaps; flaps not expanded as barbels; snout flattened, broadly parabolic to slightly pointed, length ...<|control11|><|separator|>
[22]
The Sensory Shark: High-quality Morphological, Genomic and ...
High-quality morphological, genomic and transcriptomic data for the small-spotted catshark Scyliorhinus Canicula reveal the molecular bases of sensory organ ...
[23]
Catshark - an overview | ScienceDirect Topics
Catshark refers to a group of small, slender sharks, such as those in the genus Hemiscyllium, typically not exceeding 85 cm in total length, ...
[24]
Muscle development in the shark Scyliorhinus canicula - NIH
Jun 21, 2017 · Here we provide a detailed description of the development of specific muscular units integrating the cephalic and appendicular musculature of ...
[25]
Small-spotted Catshark - Florida Museum of Natural History
Feb 10, 2025 · This small, nocturnal catshark is a light sandy color with slightly darker saddles and patches, and a lot of dark spots all over it.
[26]
Blackmouth catshark | Institute of Marine Research
Sep 30, 2024 · The blackmouth catshark (Galeus melastomus) is a small deepwater shark (Pentanchidae) that is relatively abundant along most of the Norwegian coast.
[27]
A new microendemic species of the deep-water catshark genus ...
Dec 12, 2018 · The family Pentanchidae comprises the 11 genera Apristurus (39 species), Asymbolus (9), Bythaelurus (13), Cephalurus (1), Figaro (2), Galeus (18) ...Missing: elevation | Show results with:elevation
[28]
Scyliorhinus stellaris, Nursehound : fisheries, aquarium - FishBase
Length at first maturity / Size / Weight / Age. Maturity: Lm 78.0, range 77 - 79 cm. Max length : 170 cm TL male/unsexed; (Ref ...
[29]
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0207887
[30]
Growth and maturity of the lesser‐spotted dogfish Scyliorhinus ...
Sep 27, 2021 · Length and age at first maturity were estimated as 42.6 cm and 6 years for males and 44.5 cm and 7 years for females.Missing: rate longevity
[31]
Sharks Do Not Always Grow Slowly: Tagging Data Reveal a ... - MDPI
Nov 3, 2022 · Mm females and males grow at a similar rate in the first years of life, with females attaining larger sizes at ages than males after age 4 ( ...
[32]
Sharks Violate Rensch's Rule for Sexual Size Dimorphism
Jul 4, 2024 · We find that sharks violate Rensch's rule, as the magnitude of SSD increases with body size despite sharks predominantly exhibiting female-biased SSD.Missing: rates | Show results with:rates
[33]
Age Determination, Growth and Reproduction in the Lesser-spotted ...
Aug 9, 2025 · This paper examines sexual maturity of the female lesser spotted dogfish Scyliorhinus canicula (L., 1758) in the Cantabrian Sea (north of Spain) ...
[34]
[PDF] Age Determination & Growth and Reproduction in the Lesser ...
The length at 50% maturity for males was 53.5 cm and for females was 57.0 cm. These findings increase the life history data available for S. canicula and form ...
[35]
Scyliorhinus canicula, Lesser spotted dogfish - FishBase
Colouration: color pattern with dark spots well-defined, predominantly ... Most common catshark in coastal waters of Europe (Ref. 32804). Inhabits ...Missing: coloration | Show results with:coloration
[36]
Coral Catshark | Smithsonian Ocean
Their leopard-like pattern provides camouflage as they swim through their reef habitat. Due to habitat destruction and overfishing, the coral catshark is ...Missing: coloration | Show results with:coloration
[37]
Coral Catshark - Atelomycterus marmoratus
Dorsal coloration a striking pattern of bold black and white spots and ... Coral Catshark, Atelomycterus marmoratus, Bugtong Batu Seamount, Malapascua Island, ...
[38]
Filetail Catshark – Discover Fishes - Florida Museum of Natural History
Feb 10, 2025 · Parmaturus xaniurus. This small, soft-bodied shark lives in deep ... Coloration The filetail catshark is gray-brown above, lighter below ...
[39]
shark biology - Save Our Sharks
Sharks use countershading, with darker dorsal and lighter ventral sides, and some use camouflage, like tiger sharks and wobbegongs, to blend in.Missing: catsharks | Show results with:catsharks
[40]
Biofluorescence in Catsharks (Scyliorhinidae) - Nature
Apr 25, 2016 · We examined the spectral sensitivity and visual characteristics of these reclusive sharks, while also considering the fluorescent properties of their skin.Missing: photophores | Show results with:photophores
[41]
Article Bright Green Biofluorescence in Sharks Derives from Bromo ...
Sep 27, 2019 · We describe a new form of biofluorescence from the skin of catsharks · Bromo-tryptophan-kynurenines are biofluorescent and show antimicrobial ...
[42]
[PDF] A Revision of the Catsharks, Family Scyliorhinidae
The major responsibilities of the National Marine Fisheries Service (NMFS) are to monitor and assess the abundance and geographic distribution of fishery ...
[43]
Catsharks (Family Scyliorhinidae) - iNaturalist NZ
Catsharks are ground sharks of the family Scyliorhinidae. They are one of the largest families of sharks with around 160 species placed in 17 genera.
[44]
Map showing the geographic distribution of Scyliorhinus canicula ...
Representatives of this genus are found in all oceans worldwide, with three species known from European waters, including the Mediterranean Sea. Scyliorhinus ...
[45]
World Register of Marine Species - Proscylliidae Fowler, 1941
Mar 29, 2005 · Proscylliidae Fowler, 1941 · Genus Ctenacis Compagno, 1973 · Genus Eridacnis Smith, 1913 · Genus Proscyllium Hilgendorf, 1904 · Genus Calliscyllium ...
[46]
Galeus arae | Shark-References
Galeus arae, or Roughtail catshark, has a pale yellowish brown ground with dark blotches, found in the Western Central Atlantic, and is bathydemersal at 250- ...
[47]
Description of a new species of deepwater catshark, Bythaelurus ...
Mar 5, 2012 · It is presumed to be endemic to the archipelago. The newspecies differs from its congeners in its coloration, the length of its anal-fin base, ...
[48]
(PDF) Apristurus melanoasper, a new species of deep-water ...
For example, Apristurus melanoasper was originally described from the North Atlantic Ocean [78] and subsequently identified in the western South Pacific, Indian ...
[49]
Yale Peabody Museum - Facebook
Jul 24, 2018 · Apristurus Garman, also known as ghost catsharks and demon catsharks ... Endemism is high, with 37% of species known from only one ...
[50]
Unveiling deep-sea habitats of the Southern Ocean-facing ...
Here we present the outcomes of the first deep-sea remotely operated vehicle study of previously unexplored submarine canyon systems along the southwest ...
[51]
How the Last Ice Age Shaped European Shark Migration Patterns
Sep 22, 2025 · Many previous studies on sharks suggest they move over large distances. But catsharks in the Mediterranean Sea appear to move and migrate ...
[52]
Small-spotted catshark - Facts, Diet, Habitat & Pictures on Animalia.bio
It is found primarily over sandy, gravelly, or muddy bottoms from depths of a few metres down to 400 m (1,300 ft). S. canicula is one of the most abundant ...
[53]
Swell shark | Animals - Monterey Bay Aquarium
By day, this small, harmless and well-camouflaged shark hides in rocky crevices. By night, a swell shark feeds. It actively sucks in some fishes, and captures ...
[54]
Metabolomic profiling of blood and seminal plasma in the small ...
These findings highlight alterations in both the blood and seminal plasma metabolomic profiles between aquarium-housed and wild animals.
[55]
Community–environment interactions explain octopus-catshark ...
Characterizing how benthic and pelagic seascape properties shape species interactions across space and time is pivotal to properly address community spatial ...
[56]
Scyliorhinidae - an overview | ScienceDirect Topics
Scyliorhinidae refers to a family of sharks known as catsharks, comprising 50 species, with varied habitats including deep-water and transitory environments.
[57]
Deepwater Catshark Facts and Species Information - Private Scuba
Oct 15, 2025 · The depth range for most deep-water catsharks is typically between four hundred (400) and two thousand (2,000) metres, with some going even ...<|separator|>
[58]
Cartilage and adaptations to extreme pressure: What can we learn ...
The cartilage tissues of deep-sea fish are different from mammalian cartilage types, and are adapted to the high-pressure environment they live in.
[59]
Exploring Biomechanical Adaptations of Deep-Sea Creatures
Nov 6, 2024 · ... cartilage, allowing for some compression and bending to withstand the high pressures. This increased flexibility is also not limited to just ...<|control11|><|separator|>
[60]
The buoyancy and locomotory movements of electric rays
May 11, 2009 · T. nobiliana was so buoyant because it had large livers (up to 20% by weight) containing a lot (up to 70 %) of oil of low density (0·91 g/cm3) ...
[61]
Temperature effects on the blood oxygen affinity in sharks - PubMed
Mar 5, 2018 · Although the hemoglobin (Hb) of most fish has a decreased affinity for oxygen with an increase in temperature, some regionally endothermic ...Missing: catshark | Show results with:catshark
[62]
Robot Discovers Eels and Sharks Thriving in Deep-sea Void Where ...
Jan 21, 2019 · "To our knowledge, the catshark and cusk eel represent the most hypoxia [oxygen deficiency] tolerant fish species known," Gallo told Newsweek. " ...
[63]
A comparison of the spatial ecology, trophic ecology ... - BORA – UiB
A comparison of the spatial ecology, trophic ecology, and hypoxia tolerance of Velvet belly lanternshark (Etmopterus spinax) and Blackmouth catshark (Galeus ...Missing: anoxic | Show results with:anoxic
[64]
'A Bit Spooky': The New Shark Species With Bright, White Eyes
May 12, 2023 · A newly discovered species of demon catshark is found in the deep waters off Australia. Apristurus ovicorrugatus, a long, gray shark with bright white eyes.
[65]
Food and feeding habits of the small-spotted catshark, Scyliorhinus ...
Aug 5, 2025 · The diet was composed predominantly of fish (53.1% numerical abundance and 56.6% frequency of occurrence), crustaceans (37.7% and 36.9%, ...
[66]
(PDF) Feeding habits of blackmouth catshark Galeus melastomus ...
Aug 7, 2025 · G. melastomus mostly preyed on decapod crustaceans (46% in terms of IRI), with cephalopods, euphausiids and mesopelagic fish as a secondary prey ...
[67]
Biofluorescence in Catsharks (Scyliorhinidae) - NIH
Apr 25, 2016 · Biofluorescence could also potentially help camouflage catsharks against potential predators who do have color vision, although very ...
[68]
[PDF] Food capture kinematics in the deep-water chain catshark ...
The Scyliorhinidae represent the largest family of extant sharks (within the largest order, Carcharhiniformes), and include more than 15 genera and over 100 ...
[69]
(PDF) Food capture kinematics in the deep-water chain catshark ...
Aug 7, 2025 · Where the pectoral girdle is mentioned, it is hypothesized to be immobile during suction feeding: forming a stable attachment site for the jaw- ...<|separator|>
[70]
Feeding habits of small-spotted catshark (Scyliorhinus canicula ...
Aug 6, 2025 · They are carnivorous fish species that show a transition in their dietary preferences from crustaceans to larger prey such as cephalopods and ...
[71]
Trophic habits of an abundant shark in the northwestern ...
Jul 31, 2018 · We studied the feeding ecology of the small-spotted catshark in the northwestern Mediterranean Sea using stable isotopes (nitrogen and carbon isotopic values) ...Missing: growth | Show results with:growth
[72]
Trophic habits of an abundant shark in the ... - NASA ADS
Here, we studied the feeding ecology of the small-spotted catshark in the northwestern Mediterranean Sea using stable isotopes (nitrogen and carbon isotopic ...<|control11|><|separator|>
[73]
Scyliorhinidae) off the west coast of southern Africa - Oxford Academic
In all, 637 catsharks comprising five species, smalleyed catshark, Apristurus microps (Gilchrist, 1922), Saldanha catshark, A. saldanha (Barnard, 1925), grey ...
[74]
(PDF) Reproductive biology of the blackmouth catshark, Galeus ...
Aug 7, 2025 · Mating and egg-deposition take place all year round, with two reproductive peaks of activity, in winter and summer. Egg capsules are, on average ...
[75]
Observations on the reproductive biology of three catsharks ...
Oct 18, 2010 · The reproductive mode of all species was confirmed as single oviparous (carrying only one egg case in each uterus at a time). Ovarian fecundity ...
[76]
First Analysis of Multiple Paternity in an Oviparous Shark, the Small ...
Nov 3, 2011 · Annual fecundity in catsharks from southern England has been estimated at between 29 and 62 eggs, which take 5–6 months to hatch depending on ...
[77]
[PDF] Biological observations on the nursehound, Scyliorhinus stellaris ...
Only 20 of the 27 eggs placed in Tanks 2 and 3 completed embryonic development until hatching. The length of embryonic development was 9-12 months. No embryonic ...Missing: hatchling | Show results with:hatchling
[78]
(PDF) Production, maturity, reproductive cycle and fecundity of small ...
May 2, 2025 · Scyliorhinus canicula in the Bristol Channel (sex ratios 1.2♀: 1♂) hatch at approximately 100 mm, with 50 % maturity reached at 550 mm and 520 ...
[79]
Production, maturity, reproductive cycle and fecundity of small ...
Feb 25, 2014 · The largest male and female were 521 mm and 531 mm TL, respectively and weighed 449 and 445.5 g, respectively. There was a not significant ...
[80]
https://www.sciencedirect.com/science/article/abs/pii/S1095643318302484
[81]
Diel Activity Rhythms in the Nocturnal, Bottom-Dwelling Sharks ...
4. Activity of a swell shark, Cephaloscyllium ventriosum, kept 55 days in a light and tem- perature controlled laboratory. Lower horizontal line for each day ...
[82]
[PDF] Scyliorhinus canicula, Smallspotted Catshark - IUCN Red List
Sep 17, 2014 · Range Description: This catshark is widespread in the Northeast and Eastern Central Atlantic. In the northern extent of its range, it can be ...
[83]
Survival rates and physiological recovery responses in the lesser ...
Our results showed that 95.7% of the animals survived 24 h after trawling. We confirmed that trawling elicited acute stress responses in catshark but that they ...
[84]
[PDF] High Seas Bottom Trawl Fisheries And Their Impacts On The ...
Bottom trawl fishing poses a major threat to the biodiversity of vulnerable deep- sea habitats and ecosystems. Losses of up to 95-98% of the coral cover of.
[85]
Adapting to a pollution hotspot? Catsharks shift to plastic substrates ...
Dec 10, 2024 · Scyliorhinus canicula is known to preferably lay egg cases on habitat forming invertebrates such as hydroids, sponges and bryozoans (Bo et al., ...
[86]
Shark critical life stage vulnerability to monthly temperature ...
In a 10-month experimental study, we assessed the combined impact of warming and acidification on critical life stages of small-spotted catshark.
[87]
Sharks, Rays, and Climate Change: Impacts on Habitat, Prey ...
Jul 12, 2023 · Warming ocean temperatures and more intense storms caused by climate change are impacting prey availability and habitat quality for migratory sharks and rays.<|separator|>
[88]
Overfishing drives over one-third of all sharks and rays toward a ...
Nov 8, 2021 · Overfishing is compounded by habitat loss, climate change, and pollution. Three additional main threats were identified that act in combination ...Missing: catshark | Show results with:catshark
[89]
Deep-sea fisheries - Oceans and fisheries - European Commission
Sep 11, 2024 · trawls below 800m are banned completely in EU waters, and 87 areas with vulnerable marine ecosystems (VMEs) are closed to bottom fishing ...
[90]
[PDF] Elasmobranchs of the mediterranean and black sea: status, ecology ...
Oct 9, 2012 · Overfishing, habitat degradation and slow recovery rates are potential factors that lead to such dramatic declines, especially in areas such as ...
[91]
Report of the Working Group on Elasmobranch Fishes (WGEF)
ICES WGEF provides assessments and advice on sharks, skates, and rays. In 2023, they advised on 25 stocks, with some advice changing greatly. New methods were ...Missing: program | Show results with:program
[92]
Keeping and breeding of the coral catshark (Atelomycterus ...
14 juvenile coral catsharks have been successfully reared at the Cologne Zoo Aquarium and are now available for breeding projects.
[93]
[PDF] The effects of marine protected areas on ecosystem recovery ... - HAL
Dec 1, 2020 · Specifically, MTI analysis revealed that the. 430 impacts of recreational fisheries were greater (positively and negatively) for Brown meagre.
[94]
Coral Catsharks, Atelomycterus marmoratus
Their slender body shape and ability to change coloration provide excellent camouflage, enabling them to stalk and ambush their prey with precision. While their ...
[95]
[PDF] Shark Fisheries and Trade in Europe (PDF, 200 KB) - Traffic.org
International trade by EU nations in shark and dogfish meat has been growing quite steadily for over a decade. The importance of shark meat on the EU market ...
[96]
Shark and Ray Touch Pool - Aquarium of the Pacific
Bamboo and epaulette sharks glide around the shallow touch pools, where guests can reach in and touch these gentle and graceful animals. The epaulette shark ...Missing: catshark | Show results with:catshark
[97]
Fun Facts About the 10+ Species in our Shark and Ray Touch Tank
Jul 11, 2025 · The brownbanded bamboo sharks in the Touch Tank exhibit are trained to participate in their own health care by swimming onto an underwater ...
[98]
Sharks in Aquariums | The Shark Trust
Nov 5, 2018 · Many aquariums will display smaller shark species that don't require much space in the wild, such as Smallspotted Catsharks, Nursehounds and Epaulette Sharks.
[99]
[PDF] The use of reproductive technologies in breeding programs for ...
Aug 13, 2016 · Captive breeding programs for elasmobranchs are becoming increasingly important, especially for display species that are threatened in their ...
[100]
Catshark Breeding? - Reef2Reef
Mar 23, 2023 · The keeping and breeding of coral catsharks can be classified as uncomplicated, given that sufficient swimming space and hiding places are provided.
[101]
Sharks and sustainable fishing | Marine Stewardship Council
Sustainable shark fishing is possible with improved management, and MSC labels support responsible fisheries, though illegal fishing and finning are threats.
[102]
(PDF) The Global Status of Sharks, Rays, and Chimaeras, Cultural ...
Jun 4, 2025 · 2015). Traditional use of sharks and rays as medicine dates back. centuries, especially in coastal communities highly dependent. on and ...