Sea life depending on water and light

18 02 2010

The co-relation between water and light and how the last affects the first causes a variation in the kind of sea life which a diver might be able to enjoy while practicing the sport. Water and light affect each other as well as affect the way in which humans can interact with the sea depending on them.

This co-relation between water and light affects divers not only by causing variations in their vision but also by allowing them to see completely different kinds of sea life. The sea life which a diver might be able to see at day time is completely different than the one he could enjoy during night. Besides this, sea life also varies depending on the water depth in which a diver is and the amount of light that such depth receives.

There are three main sea regions in which different amounts of light reach and in which different kinds of fauna and flora can be found. These three sea regions are: the sunlight zone, the twilight zone, and the midnight zone. Each one of the three main zones have its own characteristics and is a whole different sea world that the others. Besides these zones, the coast line is also often seen as another sea region due to the way it can also show a specific sea activity.

The sunlight zone is the water region that is closer to the surface and therefore it is the one which receives the highest amount of light. The co-relation of water and light of this zone allows more than 90% of sea species to live in it. Besides, the sunlight zone is the only one in which plants can live due to the amount of light they receive in it.

The second sea region is the twilight zone. In this zone we can find sea animals such as shrimps and squids. And the third sea region, called the midnight zone, is the deep dark sea area where light doesn`t reach. In this zone only about 1% of sea species live, and animals such as sharks have their habitats in it. The temperature in the midnight zone is almost freezing and water pressure is very high.

Source: Dive Pilot

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Diving sites – Cabo Frio (RJ)

7 12 2009



Overshadowed by the glamour of Búzios and the fame of Arraial do Cabo as a diving destination, Cabo Frio has gone almost unnoticed by Brazilian divers.

But one just needs to peruse a nautical chart to see that the place is promising. A wonderful archipelago made up of six islands that extends off the coast, providing more than 30 diving sites.

Sea conditions vary, as they do along the entire southeastern coast. Visibility can exceed 30 meters and 25 degrees centigrade and, the very next day, drop to 10 meters and 12 degress centigrade. All of this because of the famous upswelling –  a cold current responsible for the name of the cape. One of Cabo Frio’s biggest advantages is it proximity to diving sites.
Ilha Comprida – Face Norte
A rocky mesa that covers an area of approximately 40 m2,a t a depth of 4 to 6 meters. to the left, near the passage way to Laje da Alagada, there are large burrows and a high incidence of open-water fish, including barracudas. Night divings is recommended.

Ilha Comprida – Laje de Dentro
A long strip of fine sand at 10 meters, and the not-so-rare presence of large rays and small nurse sharks at rest. Near the southern tip, a large rock formation serves as shelter for many moray eels. Excellent spot for underwater photography.
Ilha Comprida
The inlet is sheltered from the Northeastern and eastern winds. A rock formation with a strip of sand in the center provides shelter for rays, turtles, lobsters, many nudibranchs and various species of fish. Tumpetfish can be found at night.

Ilha Dois Irmãos
Excellent place for open water fish, but the timing is restricted to calm ocean days. Rarely visited, it offers rich and peculiar animal life. On the western side, the current makes drift dives possible.
Ilha dos Papagaios
The site most visited by dive operators. Exciting marine biodiversity: octopuses, spotted eagle rays, soft corals, nudibranchs and tropical fish. The sea is always calm, ideal for begginers. Don’t miss the site that divides the second and third inlets: a rock formation rising up to 21 meters has beautiful entrances and small caves in its shallower part – a small cathedral. In the third inlet, passageways in a wall that descends to 28 meters.

Carolina
Carolina lies near the mouth of the Araruama channel, from where the boats depart. The shipwreck is in pieces, with only the boilers left. But its structure can be easily discerned. A good place for macrophotography and night diving.

Source: Brazil Diving Guide