Galapagos shark

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Galapagos shark
Temporal range: Pliocene–Recent [1]
Carcharinus galapagensis 1.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Subdivision: Selachimorpha
Order: Carcharhiniformes
Family: Carcharhinidae
Genus: Carcharhinus
Species:
C. galapagensis
Binomial name
Carcharhinus galapagensis
(Snodgrass & Heller, 1905)
Carcharhinus galapagensis distmap.png
Range of the Galapagos shark
Synonyms

Carcharias galapagensisSnodgrass & Heller, 1905

The Galapagos shark (Carcharhinus galapagensis) is a species of requiem shark, in the family Carcharhinidae, found worldwide. It favors clear reef environments around oceanic islands, where it is often the most abundant shark species. A large species that often reaches 3.0 m (9.8 ft), the Galapagos reef shark has a typical fusiform "reef shark" shape and is very difficult to distinguish from the dusky shark (C. obscurus) and the grey reef shark (C. amblyrhynchos). An identifying character of this species is its tall first dorsal fin, which has a slightly rounded tip and originates over the rear tips of the pectoral fins.

The Galapagos shark is an active predator often encountered in large groups. It feeds mainly on bottom-dwelling bony fishes and cephalopods; larger individuals have a much more varied diet, consuming other sharks, marine iguanas, sea lions, and even garbage. As in other requiem sharks, reproduction is viviparous, with females bearing litters of 4–16 pups every 2 to 3 years. The juveniles tend to remain in shallow water to avoid predation by the adults. The International Union for Conservation of Nature (IUCN) has assessed this species as least concern, but it has a slow reproductive rate and there is heavy fishing pressure across its range.

Taxonomy and phylogeny

The Galapagos shark was originally described as Carcharias galapagensis by Robert Evans Snodgrass and Edmund Heller in 1905; subsequent authors moved this species to the genus Carcharhinus. The holotype was a 65 cm (2.13 ft) long fetus from the Galapagos Islands, hence the specific epithet galapagensis. [3] [4]

Garrick (1982) placed the Galapagos shark and the dusky shark at the center of the "obscurus group", one of two major groupings within Carcharhinus. The group consisted of the bignose shark (C. altimus), Caribbean reef shark (C. perezi), sandbar shark (C. plumbeus), dusky shark (C. obscurus), and oceanic whitetip shark (C. longimanus), all large, triangular-toothed sharks and is defined by the presence of a ridge between the two dorsal fins. [5] Based on allozyme data, naylor (1992) reaffirmed the integrity of this group, with the additions of the silky shark (C. falciformis) and the blue shark (Prionace glauca). The closest relatives of the Galapagos shark were found to be the dusky, oceanic whitetip, and blue sharks. [6]

Distribution and habitat

Galapagos sharks are common around oceanic island reefs. Galapagos shark.jpg
Galapagos sharks are common around oceanic island reefs.

The Galapagos shark is found mainly off tropical oceanic islands. In the Atlantic Ocean, it occurs around Bermuda, the Virgin Islands, Madeira, Cape Verde, Ascension Island, Saint Helena and São Tomé Island. In the Indian Ocean, it is known from Walter's Shoal off southern Madagascar. In the Pacific Ocean, it occurs around Lord Howe Island, the Marianas Islands, the Marshall Islands, the Kermadec Islands, Tupai, the Tuamotu Archipelago, the Juan Fernández Islands, the Hawaiian Islands, the Galapagos Islands, Cocos Island, the Revillagigedo Islands, Clippperton Island, and Malpelo. There are a few reports of this species in continental waters off the Iberian Peninsula, Baja California, Guatemala, Colombia, and eastern Australia. [7]

The Galapagos shark is generally found over continental and insular shelves near the coast, preferring rugged reef habitats with clear water and strong converging currents. [4] It is also known to form groups around rocky islets and seamounts. [2] This species is capable of crossing the open ocean between islands and has been reported at least 50 km (31 mi) from land. Juveniles seldom venture deeper than 25 m (82 ft), while adults have been reported to a depth of 180 m (590 ft). [7]

Description

The Galapagos shark can be difficult to distinguish from other large requiem sharks Carcharhinus galapagensis hawaii.jpg
The Galapagos shark can be difficult to distinguish from other large requiem sharks

One of the largest species in its genus, the Galapagos shark commonly reaches 3.0 m (9.8 ft) long. The maximum length has been variously recorded as 3.3 m (11 ft) to 3.7 m (12 ft). [8] The maximum recorded weight is 195 kg (430 lb) for a 3.0 m (9.8 ft) long female (longer specimens having apparently been unweighed). [9] This species has a slender, streamlined body typical of the requiem sharks. The snout is wide and rounded, with indistinct anterior nasal flaps. The eyes are round and of medium size. The mouth usually contains 14 tooth rows (range 13–15) on either side of both jaws, plus one tooth at the symphysis (where the jaw halves meet). The upper teeth are stout and triangular in shape, while the lower teeth are narrower; both upper and lower teeth have serrated edges. [7]

The first dorsal fin is tall and moderately falcate (sickle-shaped), with the origin over the pectoral fin rear tips. It is followed by a low midline ridge running to the second dorsal fin. The second dorsal fin originates over the anal fin. The pectoral fins are large with pointed tips. The coloration is brownish gray above and white below, with a faint white stripe on the sides. The edges of the fins are darker but not prominently marked. [7] The Galapagos shark can be distinguished from the dusky shark in having taller first and second dorsal fins and larger teeth, and it can be distinguished from the grey reef shark in having a less robust body and less pointed first dorsal fin tip. However, these characters can be difficult to discern in the field. These similar species also have different numbers of precaudal (before the tail) vertebrae: 58 in the Galapagos shark, 86–97 in the dusky shark, 110–119 in the grey reef shark. [4] [7]

Biology and ecology

A Galapagos shark off Kure Atoll in the Hawaiian Islands. Carcharhinus galapagensis kure.jpg
A Galapagos shark off Kure Atoll in the Hawaiian Islands.

The Galapagos shark is often the most abundant shark in shallow island waters. [7] In their original description of this species, Snodgrass and Heller noted that their schooner had taken "several hundred" adult Galapagos sharks and that "thousands" more could be seen in the water. [3] At the isolated Saint Peter and Paul Rocks along the Mid-Atlantic Ridge, the resident Galapagos sharks have been described as "one of the densest shark populations of the Atlantic Ocean". [10] At some locations they form large aggregations, though these are not true schools. [7]

During group interactions, Galapagos sharks are dominant to blacktip sharks (C. limbatus) but deferent to silvertip sharks (C. albimarginatus) of equal size. [7] When confronted or cornered, the Galapagos shark may perform a threat display similar to that of the grey reef shark, in which the shark performs an exaggerated, rolling swimming motion while arching its back, lowering its pectoral fins, puffing out its gills, and gaping its jaw. The shark may also swing its head from side to side, so as to keep the perceived threat within its field of vision. [11] A known parasite of the Galapagos shark is the flatworm Dermophthirius carcharhini, which attaches to the shark's skin. [12] In one account, a bluefin trevally (Caranax melampygus) was seen rubbing against the rough skin of a Galapagos shark to rid itself of parasites. [13]

Feeding

The Galapagos shark usually hunts near the sea bottom. Carcharinus galapagensis.jpg
The Galapagos shark usually hunts near the sea bottom.

The primary food of Galapagos sharks are benthic bony fishes (including eels, sea bass, flatfish, flatheads, and triggerfish) and octopuses. They also occasionally take surface-dwelling prey such as mackerel, flyingfish and squid. As the sharks grow larger, they consume increasing numbers of elasmobranchs (rays and smaller sharks, including of their own species) and crustaceans, as well as indigestible items such as leaves, coral, rocks, and garbage. [7] [14] At the Galapagos Islands, this species has been observed attacking Galapagos fur seals (Arctophoca galapagoensis) and sea lions (Zalophus wollebaeki), and marine iguanas (Amblyrhynchus cristatus). [4] While collecting fishes at Clipperton Island, Limbaugh (1963) noted that juvenile Galapagos sharks surrounded the boat, with multiple individuals rushing at virtually anything trailing in the water and striking the boat bottom, oars, and marker buoys. The sharks were not slowed by rotenone (a fish toxin) or shark repellent, and some followed the boat into water so shallow that their backs were exposed. [15]

Life history

Like other requiem sharks, the Galapagos shark exhibits a viviparous mode of reproduction, in which the developing embryos are sustained by a placental connection formed from the depleted yolk sac. Females bear young once every 2–3 years. Mating takes place from January to March, at which time scars caused by male courtship bites appear on the females. The gestation period is estimated to be around one year; the spring following impregnation, females move into shallow nursery areas and give birth to 4–16 pups. The size at birth has been reported to be 61–80 cm (2.00–2.62 ft), though observations of free-swimming juveniles as small as 57 cm (1.87 ft) long in the eastern Pacific suggest that birth size varies geographically. [14] Juvenile sharks remain in shallow water to avoid predation by larger adults. [4] Males mature at 2.1–2.5 m (6.9–8.2 ft) long and 6–8 years old, while females mature at 2.2–2.5 m (7.2–8.2 ft) long and 7–9 years old. Neither sex is thought to reproduce until 10 years of age. [14] The lifespan of this species is at least 24 years. [4]

Human interactions

Galapagos shark hooked on a longline off Hawaii Carcharhinus galapagensis hooked.jpg
Galapagos shark hooked on a longline off Hawaii
Galapagos shark being tagged by researchers in the Papahanaumokuakea Marine National Monument PMNM - Tag Sharks (27618417071).jpg
Galapagos shark being tagged by researchers in the Papahānaumokuākea Marine National Monument

Inquisitive and persistent, the Galapagos shark is regarded as potentially dangerous to humans. However, several live-aboard boats take divers to Wolf and Darwin, the northernmost Galapagos islands, every week specifically to dive in open water with these sharks where they and the scalloped hammerheads accumulate in numbers, and only a few incidents have been reported. They are known to approach close to swimmers, showing interest in swim fins or hands, and are drawn in large numbers by fishing activities. Fitzroy (1839) observed off St. Paul's Rocks that "as soon as a fish was caught, a rush of voracious sharks was made at him, notwithstanding blows of oars and boat hooks, the ravenous monsters could not be deterred from seizing and taking away more than half the fish that were hooked". [10] Limbaugh (1963) reported that at Clipperton Island "at first, the small sharks circled at a distance, but gradually they approached and became more aggressive ... various popular methods for repelling sharks proved unsuccessful". The situation eventually escalated to the point at which the divers had to retreat from the water. [15] Excited Galapagos sharks are not easily deterred; driving one away physically only results in the shark circling back while inciting others to follow, whereas using weapons against them could trigger a feeding frenzy. [7]

As of 2008, the Galapagos shark has been confirmed to have attacked three people: one fatal attack in the Virgin Islands; [16] a second fatal attack in the Virgin Islands, at Magens Bay on the north shore of St. Thomas; [17] and a third non-fatal, attack off Bermuda. [7] [16] February 2018 saw a non-fatal shark attack in the Galapagos islands that shark photographer Jeremy Stafford-Deitsch suggested may have been carried out by a Galapagos shark, but the species remains unconfirmed. [18]

The International Union for Conservation of Nature (IUCN) has assessed the Galapagos shark as least concern, but its low reproductive rate limits its capacity to withstand population depletion. There is no specific utilization data available, though this species is certainly caught by commercial fisheries operating across many parts of its range. [2] The meat is said to be of excellent quality. [4] While still common at areas such as Hawaii, the Galapagos shark may have been extirpated from sites around Central America and its fragmented distribution means other regional populations may also be at risk. The populations at the Kermadec and Galapagos Islands are protected within marine reserves. [2]

Conservation status

The New Zealand Department of Conservation has classified the Galapagos shark as "Not Threatened" under the New Zealand Threat Classification System with the qualifiers "Conservation Dependent" and "Secure Overseas". [19]

Related Research Articles

<span class="mw-page-title-main">Requiem shark</span> Family of sharks

Requiem sharks are sharks of the family Carcharhinidae in the order Carcharhiniformes. They are migratory, live-bearing sharks of warm seas and include such species as the bull shark, lemon shark, spinner shark, blacknose shark, blacktip shark, grey reef shark, blacktip reef shark, silky shark, dusky shark, blue shark, copper shark, oceanic whitetip shark, and whitetip reef shark.

<span class="mw-page-title-main">Grey reef shark</span> Species of shark

The grey reef shark or gray reef shark is a species of requiem shark, in the family Carcharhinidae. One of the most common reef sharks in the Indo-Pacific, it is found as far east as Easter Island and as far west as South Africa. This species is most often seen in shallow water near the drop-offs of coral reefs. It has the typical "reef shark" shape, with a broad, round snout and large eyes. It can be distinguished from similar species by the plain or white-tipped first dorsal fin, the dark tips on the other fins, the broad, black rear margin on the tail fin, and the lack of a ridge between the dorsal fins. Most individuals are less than 1.88 m (6.2 ft) long.

<span class="mw-page-title-main">Silky shark</span> Species of fish

The silky shark, also known by numerous names such as blackspot shark, gray whaler shark, olive shark, ridgeback shark, sickle shark, sickle-shaped shark and sickle silk shark, is a species of requiem shark, in the family Carcharhinidae, named for the smooth texture of its skin. It is one of the most abundant sharks in the pelagic zone, and can be found around the world in tropical waters. Highly mobile and migratory, this shark is most often found over the edge of the continental shelf down to 50 m (164 ft). The silky shark has a slender, streamlined body and typically grows to a length of 2.5 m. It can be distinguished from other large requiem sharks by its relatively small first dorsal fin with a curving rear margin, its tiny second dorsal fin with a long free rear tip, and its long, sickle-shaped pectoral fins. It is a deep, metallic bronze-gray above and white below.

<span class="mw-page-title-main">Blacktip reef shark</span> Species of shark

The blacktip reef shark is a species of requiem shark, in the family Carcharhinidae, which can be easily identified by the prominent black tips on its fins. Among the most abundant sharks inhabiting the tropical coral reefs of the Indian and Pacific Oceans, this species prefers shallow, inshore waters. Its exposed first dorsal fin is a common sight in the region. The blacktip reef shark is usually found over reef ledges and sandy flats, though it has also been known to enter brackish and freshwater environments. It typically attains a length of 1.6 m (5.2 ft). Like other sharks, the females are larger than the males.

<span class="mw-page-title-main">Whitetip reef shark</span> Species of shark

The whitetip reef shark is a species of requiem shark, in the family Carcharhinidae, and the only member of its genus. A small shark that does not usually exceed 1.6 m (5.2 ft) in length, this species is easily recognizable by its slender body and short but broad head, as well as tubular skin flaps beside the nostrils, oval eyes with vertical pupils, and white-tipped dorsal and caudal fins. One of the most common sharks found on Indo-Pacific coral reefs, the whitetip reef shark occurs as far west as South Africa and as far east as Central America. It is typically found on or near the bottom in clear water, at a depth of 8–40 m (26–131 ft).

<span class="mw-page-title-main">Copper shark</span> Species of shark

The copper shark, bronze whaler, or narrowtooth shark is a species of requiem shark found mostly in temperate latitudes. It is distributed in a number of separate populations in the northeastern and southwestern Atlantic, off southern Africa, in the northwestern and eastern Pacific, and around Australia and New Zealand, with scattered reports from equatorial regions. The species can be found from brackish rivers and estuaries to shallow bays and harbors, to offshore waters 100 m (330 ft) deep or more. Females are found apart from males for most of the year, and conduct seasonal migrations. A large species reaching 3.3 m (11 ft) long, the copper shark is difficult to distinguish from other large requiem sharks. It is characterized by its narrow, hook-shaped upper teeth, lack of a prominent ridge between the dorsal fins, and plain bronze coloration.

<span class="mw-page-title-main">Dusky shark</span> Species of shark

The dusky shark is a species of requiem shark, in the family Carcharhinidae, occurring in tropical and warm-temperate continental seas worldwide. A generalist apex predator, the dusky shark can be found from the coast to the outer continental shelf and adjacent pelagic waters, and has been recorded from a depth of 400 m (1,300 ft). Populations migrate seasonally towards the poles in the summer and towards the equator in the winter, traveling hundreds to thousands of kilometers. One of the largest members of its genus, the dusky shark reaches more than 4 m (13 ft) in length and 350 kg (770 lb) in weight. It has a slender, streamlined body and can be identified by its short round snout, long sickle-shaped pectoral fins, ridge between the first and second dorsal fins, and faintly marked fins.

<span class="mw-page-title-main">Silvertip shark</span> Species of shark

The silvertip shark is a large species of requiem shark, in the family Carcharhinidae, with a fragmented distribution throughout the tropical Indian and Pacific Oceans. It is often encountered around offshore islands and coral reefs, and has been known to dive to a depth of 800 m (2,600 ft). The silvertip shark resembles a larger and bulkier grey reef shark, but can be easily identified by the prominent white margins on its fins. It attains a maximum length of 3 m (10 ft).

<span class="mw-page-title-main">Blacktip shark</span> Species of shark

The blacktip shark is a species of requiem shark, and part of the family Carcharhinidae. It is common to coastal tropical and subtropical waters around the world, including brackish habitats. Genetic analyses have revealed substantial variation within this species, with populations from the western Atlantic Ocean isolated and distinct from those in the rest of its range. The blacktip shark has a stout, fusiform body with a pointed snout, long gill slits, and no ridge between the dorsal fins. Most individuals have black tips or edges on the pectoral, dorsal, pelvic, and caudal fins. It usually attains a length of 1.5 m (4.9 ft).

<span class="mw-page-title-main">Caribbean reef shark</span> Species of shark

The Caribbean reef shark is a species of requiem shark, belonging to the family Carcharhinidae. It is found in the tropical waters of the western Atlantic Ocean from Florida to Brazil, and is the most commonly encountered reef shark in the Caribbean Sea. With a robust, streamlined body typical of the requiem sharks, this species is difficult to tell apart from other large members of its family such as the dusky shark and the silky shark. Distinguishing characteristics include dusky-colored fins without prominent markings, a short free rear tip on the second dorsal fin, and tooth shape and number.

<span class="mw-page-title-main">Blacknose shark</span> Species of shark

The blacknose shark is a species of requiem shark, belonging to the family Carcharhinidae, common in the tropical and subtropical waters of the western Atlantic Ocean. This species generally inhabits coastal seagrass, sand, or rubble habitats, with adults preferring deeper water than juveniles. A small shark typically measuring 1.3 m (4.3 ft) long, the blacknose has a typical streamlined "requiem shark" shape with a long, rounded snout, large eyes, and a small first dorsal fin. Its common name comes from a characteristic black blotch on the tip of its snout, though this may be indistinct in older individuals.

<span class="mw-page-title-main">Bignose shark</span> Species of shark

The bignose shark is a species of requiem shark, in the family Carcharhinidae. Distributed worldwide in tropical and subtropical waters, this migratory shark frequents deep waters around the edges of the continental shelf. It is typically found at depths of 90–430 m (300–1,410 ft), though at night it may move towards the surface or into shallower water. The bignose shark is plain-colored and grows to at least 2.7–2.8 m (8.9–9.2 ft) in length. It has a long, broad snout with prominent nasal skin flaps, and tall, triangular upper teeth. Its pectoral fins are long and almost straight, and there is a ridge on its back between the two dorsal fins.

<span class="mw-page-title-main">Hardnose shark</span> Species of shark

The hardnose shark is a species of requiem shark, in the family Carcharhinidae, so named because of the heavily calcified cartilages in its snout. A small bronze-coloured shark reaching a length of 1.1 m (3.6 ft), it has a slender body and a long, pointed snout. Its two modestly sized dorsal fins have distinctively elongated rear tips. The hardnose shark is widely distributed in the western Indo-Pacific, from Kenya to southern China and northern Australia. It inhabits warm, shallow waters close to shore.

<span class="mw-page-title-main">Spinner shark</span> Species of shark

The spinner shark is a type of requiem shark, in the family Carcharhinidae, named for the spinning leaps it makes as a part of its feeding strategy. This species occurs in tropical and warm temperate waters worldwide, except for in the eastern Pacific Ocean. It is found from coastal to offshore habitats to a depth of 100 m (330 ft), though it prefers shallow water. The spinner shark resembles a larger version of the blacktip shark, with a slender body, long snout, and black-marked fins. This species can be distinguished from the blacktip shark by the first dorsal fin, which has a different shape and is placed further back, and by the black tip on the anal fin. It attains a maximum length of 3 m (9.8 ft).

<span class="mw-page-title-main">Nervous shark</span> Species of shark

The nervous shark is a species of requiem shark, and part of the family Carcharhinidae, so named because of its timid behavior in regard to humans. It is common in shallow, coastal waters off northern Australia, Papua New Guinea, and the Solomon Islands. A small brownish or grayish shark typically measuring 1.0–1.3 m (3.3–4.3 ft) long, this species has a short, blunt snout, oval eyes, and a relatively large second dorsal fin. The leading margins of most fins are finely edged with black, and the lower caudal fin lobe is black-tipped.

<span class="mw-page-title-main">Finetooth shark</span> Species of shark

The finetooth shark is a species of requiem shark, in the family Carcharhinidae, found in the western Atlantic Ocean, from North Carolina to Brazil. It forms large schools in shallow, coastal waters, and migrates seasonally following warm water. A relatively small, slender-bodied shark, the finetooth shark can be identified by its needle-like teeth, dark blue-gray dorsal coloration, and long gill slits. It attains a maximum length of 1.9 m (6.2 ft). The diet of this species consists primarily of small bony fishes, in particular menhaden. Like other members of its family, it is viviparous with females giving birth to two to six pups in estuarine nursery areas every other year.

<span class="mw-page-title-main">Smoothtooth blacktip shark</span> Species of shark

The smoothtooth blacktip shark is a species of requiem shark in the family Carcharhinidae. It is known only from the type specimen caught from the Gulf of Aden, off eastern Yemen, and a handful of additional specimens caught from the Persian Gulf, off Kuwait. Reaching 1.3 m (4.3 ft) in length, this species has a stocky greenish-colored body, a short snout, and black-tipped fins. It can be distinguished from similar species by its teeth, which are narrow, erect, and smooth-edged.

<span class="mw-page-title-main">Smalltail shark</span> Species of shark

The smalltail shark is a species of requiem shark, and part of the family Carcharhinidae. It is found in the western Atlantic Ocean, from the northern Gulf of Mexico to southern Brazil. It inhabits shallow waters close to shore, particularly over muddy bottoms around estuaries. It tends to swim low in the water column and forms large aggregations segregated by sex. A slim species generally not exceeding 1.1 m (3.6 ft) in length, the smalltail shark has a rather long, pointed snout, a broad, triangular first dorsal fin, and a second dorsal fin that originates over the midpoint of the anal fin base. It is plain gray in color, without prominent markings on its fins.

<span class="mw-page-title-main">Blackspot shark</span> Species of shark

The blackspot shark is a small species of requiem shark in the family Carcharhinidae found in the tropical Indo-West Pacific Ocean between latitudes 24°N and 30°S, from the surface to a depth around 40 m (130 ft). Its length is a little under one meter (yard) and it is not considered to be dangerous to humans. It feeds mainly on fish, crustaceans, and squid. This shark is also caught in small-scale fisheries for human consumption.

<span class="mw-page-title-main">Spot-tail shark</span> Species of shark

The spot-tail shark, or sorrah shark, is a species of requiem shark, in the family Carcharhinidae, found in the tropical Indo-West Pacific Ocean between latitudes 31°N and 31°S from the surface to a depth around 72 m (236 ft). This shark grows to about 1.6 m. It is fished commercially over much of its range and the IUCN considers it to be near threatened.

References

  1. ↑ Bourdon, Jim. "The Life and Times of Long Dead Sharks". www.elasmo.com. Retrieved 2023-10-03.
  2. 1 2 3 4 Kyne, P.M.; Barreto, R.; Carlson, J.; Fernando, D.; Fordham, S.; Francis, M.P.; Herman, K.; Jabado, R.W.; Liu, K.M.; Pacoureau, N.; Romanov, E.; Sherley, R.B. (2019). "Carcharhinus galapagensis". IUCN Red List of Threatened Species . 2019: e.T41736A2954286. doi: 10.2305/IUCN.UK.2019-3.RLTS.T41736A2954286.en . Retrieved 19 November 2021.
  3. 1 2 Snodgrass, R.E.; Heller, E. (January 31, 1905). "Papers from the Hopkins-Stanford Galapagos Expedition, 1898–1899. XVII. Shore fishes of the Revillagigedo, Clipperton, Cocos and Galapagos Islands". Proceedings of the Washington Academy is of Science. 6: 333–427.
  4. 1 2 3 4 5 6 7 Bester, C. Biological Profiles: Galapagos Shark Archived 2010-04-30 at the Wayback Machine . Florida Museum of Natural History Ichthyology Department. Retrieved on April 26, 2009.
  5. ↑ Garrick, J.A.F. (1982). "Sharks of the genus Carcharhinus". NOAA Technical Report, NMFS CIRC-445.
  6. ↑ Naylor, G.J.P. (1992). "The phylogenetic relationships among requiem and hammerhead sharks: inferring phylogeny when thousands of equally most parsimonious trees result" (PDF). Cladistics. 8 (4): 295–318. doi:10.1111/j.1096-0031.1992.tb00073.x. hdl: 2027.42/73088 . PMID   34929961. S2CID   39697113.
  7. 1 2 3 4 5 6 7 8 9 10 11 Compagno, L.J.V. (1984). Sharks of the World: An Annotated and Illustrated Catalogue of Shark Species Known to Date. Rome: Food and Agricultural Organization. pp. 473–475. ISBN   92-5-101384-5.
  8. ↑ "Galapagos shark". FishBase.
  9. ↑ Castro, J.I. (2011). The Sharks of North America. Oxford University Press. pp. 417–420. ISBN   9780195392944.
  10. 1 2 Edwards, A.J.; Lubbock, H.R. (February 23, 1982). "The Shark Population of Saint Paul's Rocks". Copeia. 1982 (1). American Society of Ichthyologists and Herpetologists: 223–225. doi:10.2307/1444304. JSTOR   1444304.
  11. ↑ Martin, R.A. (March 2007). "A review of shark agonistic displays: comparison of display features and implications for shark–human interactions". Marine and Freshwater Behaviour and Physiology. 40 (1): 3–34. Bibcode:2007MFBP...40....3M. doi: 10.1080/10236240601154872 .
  12. ↑ Rand, T.G.; Wiles, M. & Odense, P. (April 1986). "Attachment of Dermophthirius carcharhini (Monogenea: Microbothriidae) to the Galapagos Shark Carcharhinus galapagensis". Transactions of the American Microscopical Society. 105 (2). American Microscopical Society: 158–169. doi:10.2307/3226388. JSTOR   3226388.
  13. ↑ Papastamatiou, Y.P.; Meyer, C.G. & Maragos, J.E. (June 2007). "Sharks as cleaners for reef fish". Coral Reefs. 26 (2): 277. doi:10.1007/s00338-007-0197-y. S2CID   45413817.
  14. 1 2 3 Wetherbee, B.M.; Crow, G.L. & Lowe, C.G. (1996). "Biology of the Galapagos shark, Carcharhinus galapagensis, in Hawai'i". Environmental Biology of Fishes. 45 (3): 299–310. doi:10.1007/BF00003099. S2CID   39220492.
  15. 1 2 Limbaugh, C. (1963). "Field notes on sharks". In Gilbert, P.W. (ed.). Sharks and Survival. Boston: D. C. Heath Canada, Ltd. pp. 63–94. ISBN   0-669-24646-8.
  16. 1 2 "ISAF Statistics on Attacking Species of Shark". International Shark Attack File. Florida Museum of Natural History, University of Florida. 24 January 2018.
  17. ↑ Randall, J.E. (1963). "A fatal attack by the shark Carcharhinus galapagensis at St. Thomas, Virgin Islands". Caribbean Journal of Science. 3 (4).
  18. ↑ Daniel O'Mahony (6 February 2018). "London businessman attacked by shark while snorkelling in the Galapagos Islands" . Retrieved 11 February 2022.
  19. ↑ Duffy, Clinton A. J.; Francis, Malcolm; Dunn, M. R.; Finucci, Brit; Ford, Richard; Hitchmough, Rod; Rolfe, Jeremy (2016). Conservation status of New Zealand chondrichthyans (chimaeras, sharks and rays), 2016 (PDF). Wellington, New Zealand: Department of Conservation. p. 9. ISBN   9781988514628. OCLC   1042901090.

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