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Temp: Surf 72°C
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Dive type : Aquarium
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Visibility: Good
Water: Fresh
Recent Divers in Denver, CO
Dive Profile
- 1. Air
- 12L Steel
138 → 48 bar
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- Average depth: 4.7m
Data provided by EOL.org
Species Identified
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 pili...
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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 .
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 primar...
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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 .
Hemicaranx leucurus (Günther, 1864) (Jack)
Found in coastal waters . Penetrates brackish waters . Usually forming schools . Marketed fresh and salted or dried .
Found in coastal waters . Penetrates brackish waters . Usually forming schools . Marketed fresh and salted or dried .
Heniochus diphreutes Jordan, 1903 (False moorish idol)
Occur primarily along outer reef slopes, in current channels. Juveniles in aggregations around isolated patch reefs, adults in large schools well above the bottom . In Indonesia, adults most common in depth 40-50 m, repo...
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Occur primarily along outer reef slopes, in current channels. Juveniles in aggregations around isolated patch reefs, adults in large schools well above the bottom . In Indonesia, adults most common in depth 40-50 m, reported to 200 m . Benthopelagic . Feed on plankton. Juveniles may act as cleaners ; also observed in adults . Oviparous . Form pairs during breeding .
Chelonia mydas Linnaeus 1758 (Green Turtle)
Green turtles are long-lived and may take up to 59 years to reach sexual maturity Undertaking tremendous feats of navigation, adults return to the same beach to breed each season, part of the population in Brazil astonish...
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Green turtles are long-lived and may take up to 59 years to reach sexual maturity Undertaking tremendous feats of navigation, adults return to the same beach to breed each season, part of the population in Brazil astonishingly migrates around 2,250 kilometres across the open ocean to breed on the Ascension Islands . Mating tends to occur just offshore of the nesting beaches; using a curved claw on each front flipper and a flat nail at the end of the tail, males are able to grip their mates . Females haul out onto the beach at night and dig large nests with their back flippers beyond the high tide mark, they typically lay between 100 and 150 eggs in one nest and then proceed to cover the eggs with sand; the whole process takes around two hours . A single female returns to breed only once every two to five years but will lay up to nine nests in that one season . Incubation takes between 45 and 70 days, and temperature has been shown to determine of the sex of hatchlings; with females being produced at warmer temperatures . Breaking open their eggs with a special hooked 'egg tooth' that will subsequently be lost; hatchlings use their powerful front flippers to reach the surface, and then proceed to the sea . The soft-bodied juveniles are particularly vulnerable at this time from a variety of predators, such as ghost crabs and gulls on the beach to sharks and dolphins in the water . Unlike other marine turtles, adult green turtles are almost exclusively herbivorous, grazing on seagrasses and algae ; it is assumed that juveniles are more omnivorous although the exact composition of their diet is unknown
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 shoaling...
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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 .
Etelis oculatus (Valenciennes, 1828) (Red snapper)
Inhabits rocky bottoms and feeds mainly on small fishes and squids. Abundant near oceanic islands . Small individuals are taken as by-catch in trawl fisheries . Marketed mostly fresh, sometimes frozen. Flesh of good quality.
Inhabits rocky bottoms and feeds mainly on small fishes and squids. Abundant near oceanic islands . Small individuals are taken as by-catch in trawl fisheries . Marketed mostly fresh, sometimes frozen. Flesh of good quality.
Naso brevirostris (Cuvier, 1829) (Spotted unicornfish)
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Cache
United States
Date: 2009-06-21 - 13:30
Max Depth: 7m Duration: 40mins
