Lately, there have been a couple weeks of attention to the oceans of the world, have you noticed? World Oceans Day, held every June 8th, is the United Nations-recognized day of ocean celebration and action. http://ow.ly/i/bbQzC
Watch this interesting clip. Are there different kinds of happiness and how would you relate them to diving? http://ow.ly/NKq5q
Always been confused about your camera settings and how to set them underwater? Here is a quick explanation for you to understand the basics. http://ow.ly/NewS0
The word ‘Manta’ comes from Spain and means cloak or shawl. 20 years ago we almost did not know anything about the world’s largest Ray. There are two kinds of Mantas and that is Manta Birostris (the giant ocean manta) and Manta Alfred (the resident reef manta). Mantas are close relatives to all kind of sharks and rays but do not be afraid! They only feed on the smallest organisms in the sea, like small fishes, shrimps and plankton. They are also very intelligent, curious and playful. They actually have the largest brain of all the world’s fishes!
A Manta can never stop swimming. If they do the water will stop flowing over their gills which is the way they breathe. So if they do stop, even if it is only for resting they will die. After a lot of research we now know that Mantas can travels long distance in a very short time thanks to their huge wings. They also go very deep down in the ocean, research found one 1372 meter under the surface.
The Manta Birostris is the largest one and can be up to 7 meters from wing-tip to wing-tip and can weigh up to 2000 kilos. Mantas can probably live up to 50 years and possibly for 100 years, we do not know for sure.
The epaulette shark (Hemiscyllium ocellatum) is a species of long tailed carpet shark, found in the shallow, tropical waters of Australia and New Guinea (and possibly elsewhere).
The most fascinating thing about this shark is that it doesn’t swim! It actually walks on the bottom by the help of their fins. Only if it feels really threatened it swims just to get away. The name of this shark comes from the very large, white-margined black spot behind each pectoral fin, which are significant of military epaulettes.
It’s a small shark, typically less than 1 m long and has a small body with a short head and broad, paddle-shaped fins, two on each side. This little guy feeds on small shrimps, crabs, small fish and snails. The epaulette shark has evolved to cope with the severe nighttime oxygen depletion (hypoxia) in isolated tidal pools by increasing the blood supply to its brain and selectively shutting down non-essential neural functions. It is capable of surviving complete anoxia for an hour without ill effects, and at a much higher temperature than most other hypoxia-tolerant animals.
Sadly this shark is very common for people to have in their aquariums at home due to its size, and the worst natural enemies in the ocean are bigger fishes such as larger sharks. Hopefully there are enough sharks left in the oceans so that me and you can have the opportunity to swim with one someday.
Dugong is a large marine mammal, together with manatees, they belong to order of Sirenia, which today has only four living species.
Dugongs can weigh as much as 380 kg and reach up to 3 m in length. They can live long, oldest recorded specimen reached age of 73. They have several nick names like Sea Cow, Sea Pig, Lady of the Sea, the last one comes from the Malay word duyung. Dugongs have been on the hunters list for thousands of years due their meat and oil. Closest relative to dugong, the Steller’s sea cow was hunted down in the 18th century. Today authorities are trying to save dugongs with different conservation and protection projects.
In some cultures they are legendary for their medicinal purposes. In Southern China catching dugong was thought to bring bad luck.
Did you know that actually dugongs are considered to be the inspiration for Mermaids?
Dugong populates more than 37 countries throughout Indo-Pacific. Biggest population you can find is from coast of Northern Australia. The sea of Trang province in the Andaman Sea is home to dugong as the area is rich with sea grass.
Dugongs have few natural predators, although animals such as crocodiles, orcas, and sharks pose a threat to the young.
Dugongs are called as “sea cows” because their diet consists mainly of sea-grass. Occasionally they eat jellyfish, sea squirts, and shellfish. Dugong can spend all their life in sea water, without having need for fresh water.
Due to their poor eyesight, dugongs often use smell to locate edible plants. They dig up an entire plant and then shake it to remove the sand before eating it. Sometimes they collect first a pile of plants before eating it. The muscular upper lip is used to dig the plants out, witch leaves furrows in the sand in their path. They may travel long distances to find food. As they need a lot of sea grass then usually we can’t find many dugongs in the same area. They spend most of their lives solitary or in pairs.
Dugongs may stay under water up to six minutes, dive down to 39 meters, but most probably you can meet dugong at depth of around 10 meters. Most of the dugongs in Thailand we can find in Trang province (2013 about 110-125 individuals), where a much smaller population lives in Gulf of Thailand.