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An Overview of Coral Reefs

2013-03-19T21:38:17Z

Beetleinch2: 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 reef systems] consist of thousands and thousands of tiny creatures that belong to the class anthozoans, the major class of organisms within the phylum cnidaria (the "c" is silent). Cnidaria has in excess of 6,000 identified species of sea anemones, sea pansies, sea fans and jellyfish. Corals, after their larvae stage, no longer move but are fixed in a single place. This type of animal is called a sessile animal.

Coral reef colonies are made of millions of these tiny, cup-shaped creatures known as polyps. A solitary coral polyp may be as big as a saucer or smaller than the head of a pin. Millions of polyps working in concert in a collaborative colony over many years make the limestone skeletons that form the framework of the wonderful coral reef. Corals begin life in tropical waters as free-floating larvae. Following a comparatively short period of time, the larva eventually attaches itself to a hard surface and turns into a polyp. [http://www.stevenwsmeltzer.com Coral reef] colonies reproduce both sexually and asexually. In sexual reproduction, the coral polyps discharge both eggs and sperm in the water. (This is also known as 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 create a new colony. This process is referred to as "fragmentation". Corals live in colonies consisting of many individuals, each of which is called polyp. They secrete a hard calcium carbonate (rock-like) skeleton, that serves as a consistent base or substrate for the colony. This skeleton provides two basic functions, first for the coral itself it offers shelter, as the polyps can contract into the structure if predators draw near and second this same skeletal structure is what creates the coral reefs over a period of time. The calcium carbonate is produced at the base of the polyps, consequently the living portion of the coral colony occurs at the exterior of the skeletal structure, totally covering it. The calcium carbonate deposited by the colony continually adds to the dimensions of the overall structure and thus the enlargement of the coral reef. The expansion of these reef structures varies greatly, based on the varieties of coral and environmental conditions-- ranging from 0.3 to 10 centimeters per year. The skeletons of stony corals are produced by the lower portion of the polyp. This method creates a cup, called the calice, in which the polyp is located. The walls surrounding the cup are called the theca, and the floor is called the basal plate. Thin, calcareous septa (sclerosepta), that give structural integrity, protection, and an increased surface region for the polyp's soft tissues, extend upward from the basal plate and radiate inward coming from its outer wall. From time to time, a polyp will lift off its base and produce a new floor to its cup, forming a new basal plate just above the old one. This generates a tiny chamber in the skeleton. If polyps are physically stressed or under impending attack, they contract into the calice so that virtually no part is exposed above the skeletal platform. This protects the organism from predators and the elements (Barnes, R.D., 1987; Sumich, 1996). Different varieties of coral build structures of different sizes and shapes such as brain corals, fan corals, encrusting corals, etc., creating incredible variety 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 species along with environmental conditions. Corals have only a narrow degree of organ development and consists of three basic tissue layers: an external layer or epidermis, an internal layer of cells lining the gastrovascular cavity (an internal space for digestion) and a layer called the mesoglea between the other two layers Barnes, R.D., 1987. Corals feed by reaching out with tentacles to seize quarry 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

Best Waterproof Digital Cameras

2013-03-16T20:13:50Z

Beetleinch2: Die Seite wurde neu angelegt: „There are a number of [http://www.squidoo.com/best-waterproof-point-and-shoot-camera point and shoot cameras] that are worth exploring and should be compared base…“

There are a number of [http://www.squidoo.com/best-waterproof-point-and-shoot-camera point and shoot 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 that the lens permits into the digital camera making for higher quality, less noise images. f2.0 is very fast and f3.9 is ok, although it will have more difficulty in situations where the lighting is low and may typically be a little more tricky to focus in lower light conditions. An additional attribute is the ability of the zoom lens and how much of the "zoom" is produced by the lens versus a digital zoom, where a software program is producing the zooming effect. Another feature for shooting close up would be the capability to take macro shots and how near to the subject you can come with the camera and still focus. One additional feature to think about is the ability to shoot video and the video processors speed, e.g., is the video processor high speed meaning it can capture more than 200 frames per second (fps), or else is it a low speed, e.g. around 30 fps. The faster the video processor, e.g. more fps, the the higher the quality of the video.

The evaluations of the cameras listed below gives an interesting synopsis of a number of of the best point and shoot waterproof cameras along with a suggestion on the top camera.

Water-resistant 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 waterproof point and shoot camera] setup then one of the finest underwater cameras in the extreme camera market is certainly the Olympus TG-1 iHS. This camera when purchased with the optional Olympus underwater case and strobe allows the diver to take photographs at a depth of up to 130 feet and in addition makes a very good beginning level underwater camera for both the advanced and recreational diver. TotalThe e investment consists of the camera, a rugged case that allows the diver to take the camera down to 135 feet along with an independent strobe that affords the ability to photograph in a varity of diverse situations.

Grand Cayman wreck diving - USS Kittiwake

2013-02-27T16:51:19Z

Beetleinch2:

This is a great shipwreck dive in grand cayman and one of the best in the caribbean The USS Kittiwake was reefed a little over one year and the site is maturing well. The ship has five decks, is a little over76 meters in length amd 12 meters in beam and approximately 50 feet high. The ship was built specifically for submarine rescue and was launched on July 10, 1945 and which was sunk in Grand Cayman on January 5, 2011.

This article provides an overview of what to expect on the dive a little history about the ship and information regarding the shipwreck and an guide of what you can find on the shipwreck. You can see the whole [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 wreck along with a history of the ship.

What you will find on the Dive:

The boat was reefed In january 2011 off the west side of the island at the end of Seven Mile Beach in Grand Cayman.

There are 5 decks on the 47 foot tall [http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000Wcb0w0RopvI USS Kittiwake]. To meet caymanian law regarding reefed ships, 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 radio and navigation room. The has also been removed. The Captain and executive officer's quarters are also on the upper decks.

The main deck contains the mess hall, toolshop, recompression chambers and rec room. You will see an [http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000nrOSPnFJRtU a-frame structure] on the stern which rescue divers, along with the diving bell where divers would enter to return to the ship from the ocean and then be placed in the chambers for decompression.

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 ammunition lockers, cold storage, barber shop and other areas. While the USS Kittiwake has been opened up with big[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000evHtkg3GaYQ access holes] in the sides of the ship, all of the space on the vessel was used when the boat was in service.

Make sure to lay out your dive adequately. One approach would be to begin at the stern before entry into the vessel to get photographs around the[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000MlfKl.47lgI "USS Kittiwake" logo] on the stern and also get photos by the screw (propeller) and rudder. For Divers that intend on entering the shipwreck, after you leave the stern make your way to the top of the ship then go into the funnel which is located on the Bridge Deck. If you do not plan on entering the shipwreck you can begin your investigation of the ship on the deck just above the Screw..

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 shipwreck. You can then exit the shaft on the first platform or in the cargo hold. The hold does not have any exterior exits and should only be entered by advanced divers. When you exit to the first platform you can see the Engineering logo in the Motor Room section. This area is easily accessible and can be the subject of a incredibly interesting underwater photograph close to the "[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000Y0UeUwX5JJc Engineering Mural]". The sediment can be substantial here so you must move slowly to prevent stirring up the sediment. For advanced divers you should also explore shaft alley and the front hold sections of the shipwreck. For others you can explore the various compartments on the first platform and then start making your way up one deck at a time until finally coming to the Bridge (Pilot House) where you can do your safety stop.

Look at images of additional [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 specific shipwrecks.