-
Temp: Fond 22°C
-
Type de plongée : Aquarium Shark Dive
-
Visibilité : Bonne
Type d'eau Salée
Equipement particulier utilisé
Profil de plongée
- 1. Air
- 8L Aluminium
214 → 117 bar
-
- Profondeur moyenne: 4.5m
Données fournies par EOL.org
Espèces identifiées
Carcharhinus plumbeus (Nardo, 1827) (sandbar shark)
The sandbar shark spends the majority of its time near the sea bottom, where it patrols continuously for prey , such as small bottom-dwelling fishes, molluscs and crustaceans . Whilst the diet of the adult consists pr...
Lire la suite
The sandbar shark spends the majority of its time near the sea bottom, where it patrols continuously for prey , such as small bottom-dwelling fishes, molluscs and crustaceans . Whilst the diet of the adult consists primarily of fish, the pups appear to feed more on soft blue crabs . Despite its size and large triangular teeth, the sandbar shark has never been blamed for attacks on humans, preferring instead to stick to its live fish meals . Like most other members of the Carcharhinidae family, the sandbar shark is viviparous, giving birth to between 1 and 14 pups in each litter . The size of the litter varies depending on the size of the mother, with large females giving birth to larger litters . Pregnancy is estimated to last from 8 to 12 months , and appears to differ between geographical locations . The time of year in which the pups are born also varies slightly, but all females move inshore to shallow nursery areas to give birth . These nursery grounds are separated from the normal ranges of adults , and presumably offer the young a calm, food-rich environment in which to begin their lives. The females leave these coastal areas soon after giving birth, while the young remain in the nursery grounds until winter , when they move into warmer and deeper water . A common feature of sharks is their slow growth rate and low reproductive output. Estimates of the age at which the sandbar shark matures range from eight to ten years in Hawaii , to between 12 and 15 years of age in the Northwest Atlantic Ocean . Females give birth every other year at most . Populations of sandbar sharks appear to segregate by age .
Carcharias taurus Rafinesque, 1810 (sand tiger shark)
The sand tiger shark is one of the best-studied of the shark species. They are the only sharks known to gulp air at the surface and store it in their stomach to provide buoyancy . These sharks generally mate between Oc...
Lire la suite
The sand tiger shark is one of the best-studied of the shark species. They are the only sharks known to gulp air at the surface and store it in their stomach to provide buoyancy . These sharks generally mate between October and November and courtship can take a long time, with the male aggressively nipping his potential mate . Females are ovoviviparous, giving birth to two large pups every two years. Pups hatch out of their eggs within the oviduct of the mother's reproductive system, one in each oviduct, and then feed on eggs that the female continues to produce . Over nine months to a year, the pups grow within their mother feeding on hundreds to thousands of eggs and, by the time they are born, measure up to a metre long . During the day they are found near caves and ledges , hovering just above the surface either singly or in small groups . These fairly docile sharks are sluggish and, despite a ferocious reputation, feed mainly on fish .
Ginglymostoma cirratum (Bonnaterre, 1788) (Nurse shark)
During the day the nurse shark is a sluggish animal, spending most of its time resting on sandy bottoms, or in crevices in rocks and coral reefs. Often several nurse sharks may congregate when resting, sometimes even ...
Lire la suite
During the day the nurse shark is a sluggish animal, spending most of its time resting on sandy bottoms, or in crevices in rocks and coral reefs. Often several nurse sharks may congregate when resting, sometimes even piling on top of one another . At night however, the nurse shark actively roams the sea bottom and reef for prey. It feeds on bottom invertebrates such as spiny lobsters, shrimps, crabs, sea urchins, squid and octopi . It is also feeds on fish, its nocturnal nature enabling it to prey on resting fish that would be too active during the day to capture . The nurse shark's small mouth and large pharynx enable it to feed by a unique suction method, effectively making the nurse shark the 'hoover' of the ocean floor. By cupping its mouth over a hole or crevice and expanding its throat, it creates a vacuum that sucks prey out of their hiding . This suction-feeding is also useful for extracting snails from their shells , and it will dig in sand to root out prey sensed by its fleshy barbels . The nurse shark is one of few sharks in which courtship behaviour is relatively well known . The male swims alongside the female, grabs one of the pectoral fins in his mouth, rolls her over and they mate . A large number of males will often try to mate with a single female, and females often bear numerous bite-scars and bruises received during mating attempts. It is therefore not surprising that females frequently try to avoid males by swimming in very shallow water, where they can bury their pectoral fins in the sand . Nurse sharks are ovoviviparous , a method of reproduction whereby the young develop inside a weakly-formed egg shell within the mother, receiving nourishment from their yolk sac, for five to six months . The females move to shallow seagrass beds and coral reefs to give birth to 20 to 30 pups in late spring and summer . Like many sharks the nurse shark is slow growing, with males not reaching maturity until 10 to 15 years of age, and females 15 to 20 years .
Pristis pectinata Latham, 1794 (smalltooth sawfish)
The sawfish uses its saw to catch prey in two ways; firstly by using it as a rake to sift through the sand for crustaceans such as crabs and shrimps, and secondly by using it as a sword to swipe through schools of shoa...
Lire la suite
The sawfish uses its saw to catch prey in two ways; firstly by using it as a rake to sift through the sand for crustaceans such as crabs and shrimps, and secondly by using it as a sword to swipe through schools of shoaling fish such as mullet, lacerating or stunning individuals. The smalltooth sawfish is predated on by sharks, but only when it is young and undersized . Little is known about the life cycle of the smalltooth sawfish but it is thought to breed year round in areas of constant climate, but elsewhere, only in the summer. Fertilisation is internal and the pups develop inside the female, who gives birth a year later to 15 to 20 pups. The saws of the newborns are sheathed and malleable at birth for protection. The pups are around 60 cm long at birth .
Muraena retifera Goode and Bean, 1882 (Moray eel)
Known only from moderate depths along outer continental shelf.
Known only from moderate depths along outer continental shelf.
Partager sur les Réseaux Sociaux
Lien direct vers cette plongée
Toutes les informations de cette plongée seront définitivement supprimées (profil de plongée, notes, espèces, photos,...) Êtes-vous certain ?
Vous devez sélectionner au moins une plongée à importer sur Diveboard
Cette plongée va être copiée dans votre carnet de plongée.
Veuillez indiquer quels infos vous souhaitez conserver.
Cette plongée a été copiée dans votre carnet de plongée.
Diveboard participe aujourd'hui au concours de startups Techcrunch Disrupt. Montrez que vous aimez Diveboard en votant pour nous !
Un seul clic est nécessaire !
Cette fenêtre ne s'affichera qu'une seule fois. N'oubliez pas de voter avant de la fermer ! Merci !
Greg Dietz
États-Unis
Date : 2009-07-26 - 16:00
Profondeur Max: 6.7m Durée : 35mins
