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What Are Coral Reefs

2013-03-30T03:52:35Z

Prison15pike: Die Seite wurde neu angelegt: „[http://blog.stevenwsmeltzer.com/what-are-coral-reefs/introduction-to-the-underwater-world/ What Are Coral Reefs] - Introduction to the Underwater World [http://…“

[http://blog.stevenwsmeltzer.com/what-are-coral-reefs/introduction-to-the-underwater-world/ What Are Coral Reefs] - Introduction to the Underwater World
[http://blog.stevenwsmeltzer.com/what-are-coral-reefs/ Coral reefs] consist of tiny animals which belong to the class anthozoans, the major class of organisms within the phylum cnidaria (the "c" is silent). Cnidaria has more than 6,000 recognized species of jellyfish, sea pansies, sea anemones and sea fans. Corals, subsequent to their larvae stage, aren't mobile but rather stay permanently in one place. This type of animal is called a sessile animal.

[http://www.stevenwsmeltzer.com Coral reef] colonies are made of millions of these very small, cup-shaped animals termed polyps. A solitary coral polyp might be as big as a saucer or smaller than the head of a pin. Millions of polyps working together in a collaborative colony generation after generation create the limestone skeletons that create the framework of the wonderful coral reef. Corals begin life in tropical waters as free-floating larvae. Following a relatively short period of time, the larva eventually attaches itself to a hard surface and turns into a polyp. Coral reef colonies reproduce both sexually and asexually. In sexual reproduction, the coral polyps release both eggs and sperm in the water. (This is also called coral spawning.) One kind of asexual reproduction happens when fragments of coral are broken off as a consequence of storm storms. The broken pieces of corals more often than not survive and continue to grow and make a new colony. This process is referred to as "fragmentation". Corals live in colonies consisting of numerous individuals, each of which is called polyp. They produce a hard calcium carbonate (rock-like) skeleton, which serves as a uniform foundation or substrate for the colony. This skeleton provides two fundamental functions, first for the coral itself it offers safety, as the polyps can contract into the structure if predators draw near and second this same skeletal construction is what creates the coral reefs over time. The calcium carbonate is produced at the base of the polyps, consequently the living portion of the coral colony occurs at the surface of the skeletal structure, totally covering it. The calcium carbonate deposited by the colony continually adds to the dimensions of the general structure and thus the growth of the reef. The growth of these coral reef structures differs greatly, based on the species of coral and environmental conditions-- ranging from 0.3 to 10 centimeters per year. The skeletons of stony corals are secreted by the lower portion of the polyp. This process produces a cup, called the calice, in which the polyp rests. The walls around the cup are called the theca, and the floor is called the basal plate. Thin, calcareous septa (sclerosepta), which give structural integrity, shelter, and an increased surface area for the polyp's soft tissues, extend upward from the basal plate and radiate inward from its outer wall. Periodically, a polyp will raise up off its base and secrete a new floor to its cup, forming a new basal plate just above the old one. This produces a tiny chamber in the skeleton. If polyps are physically stressed or under possible attack, they contract into the calice so that almost no part is exposed above the skeletal platform. This protects the organism from predators and the elements (Barnes, R.D., 1987; Sumich, 1996). Different species of coral build structures of different dimensions and shapes such as brain corals, fan corals, encrusting corals, etc., making fantastic diversity and complexity in the coral reef ecosystem. Various coral species tend to be segregated into characteristic zones on a reef, separated out by competition with other varieties along with environmental conditions. Corals have only a limited level of organ development and consists of three basic tissue layers: an external layer or epidermis, an inner layer of cells lining the gastrovascular cavity (an internal space for digestion) and a layer known as the mesoglea in between the other two layers Barnes, R.D., 1987. Corals feed by reaching out by means of tentacles to seize prey such as small fish and planktonic animals (any drifting organisms, animal, plant, archaea or bacteria that inhabit the pelagic zone of the oceans). See Also: Creatures of the Coral Reefs Resources: Marine Species Galleries: Coral Reef Images Pictures of Fish Sea Turtles Crustaceans and Echinoderms Moray Eels Detailed Information on select Marine Species: Caribbean Fish Hawaiian Fish Sponges Crustaceans, Invertebrates, Mollusks, Echinoderms

Which is the Best Point and Shoot Camera?

2013-03-20T23:08:38Z

Prison15pike: Die Seite wurde neu angelegt: „There are a number of digital cameras that are worth exploring and should be compared based upon fetures such as lens speed or the "f-stop" rating. The faster the…“

There are a number of digital cameras that are worth exploring and should be compared based upon fetures such as lens speed or the "f-stop" rating. The faster the lens., e.g., the lower the f-stop number the better and the more light which the lens permits into the digital camera making higher qualtity less noisy images. f2.0 is very fast and f3.9 is ok, although will not take as good a picture in situations where the lighting is low and can typically be more difficult to focus in lower light conditions. Another feature is the ability of the zoom lens along with how much of the "zoom" is created by the lens compared to a digital zoom, where a software program is generating the zooming effect. One more feature for taking pictures close up would be the capability to take macro photographs and how near to the subject you can come with the camera and still focus. One other feature to consider is the ability to take video and the video processors speed, e.g., is the video processor high speed meaning it will capture in excess of 200 frames per second (fps), or else is it a low speed, e.g. around 30 fps. A faster vidwo processor will create higher quality videos.

The evaluations of the waterproof digital cameras listed below offers a good quality synopsis of a number of of the best point and shoot waterproof cameras along with a suggestion on the top camera.

Waterproof cameras reviewed:
<ol>
<li>Panasonic Lumix TS4 12.1 TOUGH Waterproof Digital Camera with 4.6x Optical Zoom
<li>Nikon COOLPIX AW100 16 MP CMOS Waterproof Digital Camera with GPS and Full HD 1080p Video
<li>Canon PowerShot D20 12.1 MP CMOS Waterproof Digital Camera with 5x Image Stabilized Zoom 28mm Wide-Angle Lens a 3.0-Inch LCD and GPS Tracking
<li>Fujifilm XP170 Compact Digital Camera with 5xOptical Zoom Lens
<li>Olympus Stylus TG-830 iHS Digital Camera with 5x Optical Zoom and 3-Inch LCD
<li>Pentax Optio WG-1 Adventure Series 14 MP Waterproof Digital Camera with 5x Wide-Angle Optical Zoom
<li>Olympus TG-1iHS 12 MP Waterproof Digital Camera with 4x Optical Zoom
</li>
</ol>

If you're prepared to spend about $1,000 to obtain the [http://www.squidoo.com/best-waterproof-point-and-shoot-camera best underwater camera] setup then one of the finest underwater cameras in the extreme camera market is definitely the Olympus TG-1 iHS. This camera when bought with the optional Olympus underwater case and strobe enables the diver to take pictures at a depth of up to 130 feet and in addition makes a very decent entry level underwater camera for any diver. TotalThe e investment includes the camera, a rugged case which permits the diver to take the camera down to 135 feet along with an independent strobe that affords the ability to shoot in a varity of diverse situations.

Wreck diving Grand Cayman - USS Kittiwak

2013-03-14T02:07:40Z

Prison15pike:

This is the top wreck dive in Grand Cayman and one of the best in the Caribbean. The USS Kittiwake was reefed a about 18 months ago and the shipwreck site is maturing well. The shipwreck has five decks, is 251.6 ft (76.7 m) in length, 42ft (12.8 m) in beam and around 50 feet high. The ship was designated specifically for submarine rescue and was launched on July 10, 1945 and which was sunk in Grand Cayman on January 5, 2011.

The following is a description of the dive, some history and information about the vessel and an guide of what you can find on the wreck. You can see the entire [http://stevenwsmeltzer.com/gallery/Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/ photo gallery] on the web site and/or see the blog entry for the [http://blog.stevenwsmeltzer.com/dive-site-reviews-and-listings/dive-sites/scuba-diving-grand-cayman-uss-kittiwake-shipwreck/ USS Kittiwake] for supplementary data on the shipwreck plus a history about the ship.

What you will find on the Dive:

The ship was reefed January 5, 2011 off the north end of Seven Mile Beach in Grand Cayman.

There are five decks on the [http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000Wcb0w0RopvI USS Kittiwake]. To meet caymanian requirements for wrecks, a portion of the upper mast was removed. The are two bridges on the upper decks (both an external and internal bridge to allow operations in heavy seas) along with the navigation and radio rooms. The has also been removed from the ship. The Captain and executive officer's quarters are also on the upper decks.

On the main deck, from bow to stern, internally you will find the rec room, mess hall, ironing room, small tool workshop and recompression chambers.. You will note the large [http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000nrOSPnFJRtU a-frame structure] on the stern that supported submarines and hard hat divers, along with the diving bell that was used to bring back divers to the ship and to then move to the recompression chambers

The crews quarters, the engine room and medical facilities are located below the main deck along with ,[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000QmV9jUuDJyQ air bank storage] and compressors, as well as the steering gear, shaft, gyro, ammunition lockers, cold storage and barber shop to name a few areas. While there are now a number of big[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000evHtkg3GaYQ access holes] in the sides of the ship, every space on the vessel was utilized while in service.

It is important to plan your dive well. I would recommend heading to the stern prior to entry into the ship to take photographs around the[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000MlfKl.47lgI "USS Kittiwake" logo] on the the backof the ship and also get pictures by the screw (propeller) and rudder. For Divers that plan on penetrating the shipwreck, you can then make your way to the top of the ship then enter via the main funnel that is on on the Bridge Deck. If you do not intend on entering the wreck you should begin your exploration on the deck just above the Propeller.

The main [http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000ndu7PcxF.bM entry through the funnel makes an excellent underwater photograph] . try silhouetting your dive partner in the shaft diving down into the wreck. You can then exit the shaft on the first platform or in the cargo hold. Note the hold deck does not have any exterior exit points and is not recommended for divers that do not have an advanced certification and prior wreck experience. When you exit to the first platform you will be able to see the Engineering emblem in the Motor Room section. This area is easily accessible and makes for a especially good underwater photo near the "[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000Y0UeUwX5JJc Engineering Mural]". The sediment can be heavy at this point so you need to move slowly to prevent clouding up the water. For experienced divers you may also look at shaft alley and the front hold regions of the ship. For others you can view the various compartments on the first platform and then start going up deck by deck until finally arriving at the Bridge (Pilot House) where you can do your safety stop.

Review images of other [http://stevenwsmeltzer.com/gallery/Shipwrecks/G0000OtMyTETA74I/ shipwrecks] on http://www.stevenwsmeltzer.com or visit his [http://blog.stevenwsmeltzer.com/dive-site-reviews-and-listings/dive-sites/scuba-diving-grand-cayman-uss-kittiwake-shipwreck/ blog] for reviews of other shipwrecks.