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Fish round up : The prehistoric Coelacanth

par Ksso le 23 février 2011

Life origins from the oceans, that's something we've all learned at school. We also learned that at some point during the evolutions fish started wandering on the firm ground and got new appendixes to help them move on the ground more easily.The coelacanth (pronounced SEEL-uh-kanth) was thought to be extinct since the cretaceous period ( 70 to 140 million years ago). They are considered to be the link between the fish and the tetrapods (all things four-legged). With much surprise one specimen was fished in 1938 off the east coast of south africa and scientists discovered that the species is still present but only migrated to deeper water. Subsequently, a second species was fished in 1998...

Fish round up : the Sperm Whale

par Ksso le 16 février 2011

Sperm Whale Encounter from Howard Hall on Vimeo.

The sperm whale, also known as the common cachalot, can grow 20.5 meters long (67 ft), is the largest living toothed animal. The head can take up to one-third of the animal's length giving him the lagest brain of any animal on earth. It can live for 70 years.The sperm whale emits clicking vocalizations but while it's the loudest sound produced by any animal its function remains uncertain.It has been widely hunted between the 18th and late 20th century for the spermaceti (a white substance found in the animal's head and giving him the name), sperm oil and ambergris (a biliary secretion ) it produces and which are used in the perfume and...

An artificial reef made of 400 sculptures

par Ksso le 15 février 2011

Jason de Caires Taylor isn't a newbie in the matter with almost a dozen artificial reefs created on his record. His modus operandi is always the same, he designs a few sculptures that he drowns on a sandy spot at shallow depth (under 10m). But this time he outdid himself with his latest production "La Evolución Silenciosa" . With 400 sculptures drowned by 9m depth between Cancun and las islas Mujeres in Mexico, he created the biggest Arty-ficial reef.Contrary to other artificial reefs, Jason's don't get implanted with corals branches, which would have considerably sped up the coral creation. But overtime hopefully coral will grow and a whole new marine life will make this sculpture their...

Fish round up : the Cuttlefish

par Ksso le 13 février 2011

Contrary to its name, the Cuttlefish is a mollusk of the class Cephalopoda (just like the Squid and Octopus). The Cuttlefish is fairly widespread and can be easily spotted in Europe and Asia. The Cuttlefish has only one "bone", the cuttlebone, which works as an internal shell. They range from 15 to 25cm (5.9 to 9.8in)The Cuttlefish is fairly remarkable by its ability to change its skin color in seconds, just like a chameleon. He can do so either as a camouflage or as a means to communicate with fellow cuttlefish. Their skin is made of groups of red, yellow, brown, and black pigmented chromatophores above a layer of reflective iridophores and leucophores at a resolution of 359 DPI -...

Know your gear : the regulator

par Ksso le 12 février 2011

The regulator is a key piece of the diver's gear. Like my instructors used to repeat relentlessly "Air is life", and the regulator bring breathable air to your mouth. The main function of a regulator is fairly simple:

Adjust the air pressure (from the tank pressure to the environment pressure)

Enable inhale and exhale of the air

The classic regulator is composed of 2 stages. The first stage mounts right on the tank and will adapt the tank's air pressure to the environment. Standard 1st stage regulators also include a high-pressure plug to connect to the manometer and get a direct reading to the tank's pressure (and letting you know hom much air you've got left).A 1st stage regulator...

Laser sizing

par Ksso le 11 février 2011

Classic conversation after a dive :

Diver1 : Have you seen the grouper - it was huuuuge ! almost 2 meters long ! (note : that's unlikely ). Check out the pic I took !Diver2 : Bull***** - You kiddin', that's more like 20cm tops...

Now, there's a real point in that conversation : evaluating the proper size of something underwater wether it's a fish, a wreck or a cave, is quite complicated. And the pictures taken do miss scale to enable proper evaluation of the subject size.Working with the University of Queensland, the Marine Megafauna Foundation and CSIRO Marine and Atmospheric Research, a team of researchers led by Chris Rohner has come up with a new technique to add a scale to underwater...

San Fruttuoso's "Christ of the Abyss"

par Ksso le 9 février 2011

A few dive sites have been staged with intentionally drowned elements to attract divers. The Christ of the Abyss is a 8.5 feet tall 4000 pound bronze sculpture which has been drowned in 1954 at 55 feet depth in Mediterranean Sea off San Fruttuoso between Camogli and Portofino on the Italian Riviera.The statue was removed in 2003 and restored.Shallow high profile spur and groove coral formations are surrounded by relatively flat, coral and sponge encrusted hard bottom, and sand. Large Spotted Eagle Rays and Southern Stingrays are often sighted near the sandy perimeter.View Larger Map

Fish mondays : the Pufferfish (& the Fugu)

par Ksso le 8 février 2011

The Pufferfish ( scientific name : Tetraodontidae) is a fairly common fish that can be encountered especially easily on the US , Australian and western African coasts. The Puffer fish can be also referred ad balloonfish, blowfish, bubblefish, globefish, swellfish, toadfish, toadies, honey toads, sugar toads, and sea squab and represents a family of about 121 species within 20 genera.The blowfish eat mostly crustaceans and mollusks whose shells they crush with their four teeth (thus the scientific name).Puffer fish are generally believed to be the second–most poisonous vertebrate in the world, after the Golden Poison Frog. One of its best known representant is the japanese Fugu fish which...

Discovery Channel : Special forces combat diving

par Ksso le 7 février 2011

Military operation is nothing near usual diving. In this documentary follow the 6-weeks training course of special forces as they are transformed from combat swimmer to combat diver.This documentary aired on Discovery Channel.

How nets kill to protect our fears

par Ksso le 6 février 2011

Shark Angels - on Shark Nets from Shark Angels on Vimeo.

Very striking video made by the "Shark Angels" about the rampage done by nets. The most appalling thing is that those net don't only target sharks but dolphins, turtles and other harmless animals die there too.Again, it's a recall that actually few types of sharks are dangerous: of the existing 368 species of sharks, only 20 are dangerous to humans. Of them, four account for almost 60-70 shark attacks registered annually worldwide.If you were as appalled as I was by those images, go ahead and sign the petition at removethenets.com .