Rhincodon typus Smith, 1828 (Whale shark)These sharks are usually solitary, but loose groups of up to 100 individuals have been sighted, often when they are feeding . Whale sharks appear to be highly migratory , and have been tracked for thousands of kilometres .... Read MoreThese sharks are usually solitary, but loose groups of up to 100 individuals have been sighted, often when they are feeding . Whale sharks appear to be highly migratory , and have been tracked for thousands of kilometres . Individuals who regularly visit the Ningaloo Reef in Australia, between March and May every year, appear to be mainly immature males . It is not clear whether movements across deep ocean basins follow prey routes or are undertaken for other reasons. Very little is known about the reproduction of the world's largest fish, but in 1995, one pregnant female was captured who contained nearly 300 foetuses . The species is ovoviviparous; the young hatch from eggs retained within the mother so that she then gives birth to live young. Whale sharks are fairly docile creatures and feed on planktonic organisms and small fish by suction filter-feeding . This species is thought to be a more dynamic filter-feeder than, for example, the basking shark, actively sucking food in through their vast mouths and passing the water over the gill arches, where prey are retained and then swallowed . They have also been observed actively swimming through shoals of fish with their mouth agape or hanging vertically in the water and drawing food into their mouths .
Prionace glauca (Linnaeus, 1758) (Blue shark)Blue sharks are viviparous, giving birth to live young after a gestation period of nine to twelve months . Up to 135 pups can be born per litter, partially depending on the size of the female, but the average is 25 to 50 ... Read MoreBlue sharks are viviparous, giving birth to live young after a gestation period of nine to twelve months . Up to 135 pups can be born per litter, partially depending on the size of the female, but the average is 25 to 50 . Maturity is reached at approximately five to six years old and blue sharks are known to have lived to 20 years . Although often observed cruising slowly and sluggishly the blue shark is capable of rapid movement if it is excited or feeding . This species will often circle its prey before moving in to attack it. Blue sharks primarily feed upon relatively small prey, such as bony fish and squid, but will also take larger prey including mammalian carrion .
Share on Social Networks
personalize your shared text as well as its destination (wall, page...) or send as a private message to a friend
Almost flat calm seas. Easy access to dive site from the cul de sac. High tide was at 19:00 approx. Visability was down to about 3-4 m with quite a lot of sediment in the water. Still, it was an excellent dive and the sunset on surfacing was amazing. Few fish about, mostly starfish and crab.
Este mergulho serviu para testar a utilização de fatos secos, uma vez que nunca tinha experimentado.
A experiência não foi muito agradável uma vez que o fato me estava muito apertado no pescoço e senti algumas dificuldades ao respirar e ao mexer-me.