What is Shark Diving?
Shark diving, or cage diving, allows divers, researchers and film crews to view the extraordinary world of Great White Sharks in comfort and safety. Specially designed shark viewing cages provide adequate protection for the sharks from sport divers, while allowing divers total freedom of movement and panoramic views. Our shark diving crews are industry professionals who care about your safety and enjoyment. Equally important, they care about making our dives safe for the sharks.
Is Shark Diving Dangerous?
To date, our most serious injury has been a sunburn. White sharks have many myths surrounding them. One is that they are killing machines attacking anything in sight. We have found that even at the height of a feeding event with multiple animals around a carcass, white sharks prove to be shy, slow moving animals. Our divers are amazed to learn first hand that these animals are almost gentle. That said, divers should always maintain a healthy respect for these awesome predators, in and out of the water!
Showing posts with label Scuba Jay. Show all posts
Showing posts with label Scuba Jay. Show all posts
Tuesday, August 12, 2008
Monday, February 25, 2008
DIVING WITH SHARKS

DIVING WITH SHARKS AND RAYS
Source of post: http://elasmodiver.com/Shark%20diving%20101.htm
First and foremost, I can't stress enough the need to gain as much knowledge as possible about the animals and their environment. To go into the water without at least a basic idea of how the sharks are likely to react is foolhardy to say the least. If you are participating in an organized "shark diving experience" you may feel that the operator's knowledge is sufficient and that you can sit back and watch the show. It's important to remember that every shark interaction is different. Just because countless people have watched the parade of sharks at a particular site passively swim by does not mean that you will have the same experience. Following are some guidelines for minimising the dangers associated with interacting in the wild with sharks and rays. Whilst the advice hopefully is useful it should be regarded as a vague guideline only. Your experiences will differ greatly from mine and the sharks and rays you encounter may react in a completely different way. As such, I take no responsibility for the outcome of any encounters that you may have or for the validity of any information stated below.
1. Get educated!
Ask local divers and fishers what species of sharks you are likely to see. Knowing if an area is frequented by nurse sharks or tigers may make a big difference to how alert you feel you need to be on the dive. Learn the stats on different sharks. The shark attack file is a good place to start to find out which sharks have been responsible for attacks in the past.
Find out how the sharks in the area normally respond to divers. Most free swimming sharks will disappear the minute they see a noisy, bubble blowing diver heading their way but some sharks are more curious. Occasionally sharks like to wander up to divers and give them a closer look. Being buzzed or even brushed by a shark does not necessarily mean that you are about to become lunch.
First and foremost, I can't stress enough the need to gain as much knowledge as possible about the animals and their environment. To go into the water without at least a basic idea of how the sharks are likely to react is foolhardy to say the least. If you are participating in an organized "shark diving experience" you may feel that the operator's knowledge is sufficient and that you can sit back and watch the show. It's important to remember that every shark interaction is different. Just because countless people have watched the parade of sharks at a particular site passively swim by does not mean that you will have the same experience. Following are some guidelines for minimising the dangers associated with interacting in the wild with sharks and rays. Whilst the advice hopefully is useful it should be regarded as a vague guideline only. Your experiences will differ greatly from mine and the sharks and rays you encounter may react in a completely different way. As such, I take no responsibility for the outcome of any encounters that you may have or for the validity of any information stated below.
1. Get educated!
Ask local divers and fishers what species of sharks you are likely to see. Knowing if an area is frequented by nurse sharks or tigers may make a big difference to how alert you feel you need to be on the dive. Learn the stats on different sharks. The shark attack file is a good place to start to find out which sharks have been responsible for attacks in the past.
Find out how the sharks in the area normally respond to divers. Most free swimming sharks will disappear the minute they see a noisy, bubble blowing diver heading their way but some sharks are more curious. Occasionally sharks like to wander up to divers and give them a closer look. Being buzzed or even brushed by a shark does not necessarily mean that you are about to become lunch.
Are the sharks in the area regularly fed by divers? It can be disconcerting to drop down onto an area of reef where shark feeds normally take place and immediately find yourself surrounded by expectant sharks.
Ask if bait will be used or if any member of the dive group is planning to spear fish. Aggressive behaviour is significantly increased in the presence of struggling fish or when blood and other juices are in the water.
Find out if the sharks in the area are territorial. Sharks may respond to divers as threats to territory and defensively attack.
2. Dress appropriately.
There are differing points of view on the subject of what colors are most likely to attract a shark's attention. Every conceivable color combination has been tried at one time or another in an effort to deter sharks from attacking. Even broad black and white stripes have been tried in an effort to replicate the appearance of a banded sea snake which is an animal avoided by the majority of shark species.
As a rule of thumb, tropical sharks are mainly fish eaters and as such are attracted to bright and shiny objects. Therefore it would seem logical that a neon yellow wetsuit would attract the attention of sharks looking for a meal. In shark diving circles neon yellow has actually been given the nickname of "yum yum yellow". Other bright colours may also have the same effect so if you're planning on regularly putting yourself in the presence of tropical fish eating sharks it may be a good idea to tone down your fashion statement and choose a more muted color or black. Bear in mind that thousands of divers swim with tropical sharks every day wearing all manner of clothing from bikinis to camouflaged full body dive skins and the incidence of attack is extremely low.
If you have bright metal objects such as reels or dive knifes attached to the outside of your BC try to stash them out of sight in a pocket or replace them with darker coloured alternatives. Even a diver's first stage can look good to a hungry reef shark as I found out in the Bahamas.
Wear dark gloves. From a shark's point of view there's nothing more tempting than seeing two small lily white "fish" flapping around in front of them. If you don't have any gloves try to keep your arms folded across your chest. Using your hands to swim with is asking for trouble.
Full suits are better than shorty wetsuits. This is the same principle as exposing your hands. try not to expose distinct areas of skin that a shark can focus on or mistake for a fish. Even if you have dark skin it's a good idea to cover up. A lot of injury can occur from the brush of a shark's sandpaper like skin.
Some sharks in temperate seas feed on seals and sea lions. The chances are that you will never see a white shark under water. I have a friend that lives on Catalina Island who has seen a couple but he considers himself very lucky indeed to have done so. Many divers prefer the tough guy black commando look and this is reflected by the choices of suits that manufacturers offer. Personally I think that mimicking a seal doesn't seem like such a good idea. Keep in mind again that there are plenty of fish eaters in temperate seas as well, including smaller white sharks, so flashing bright colours and shiny objects may also be unwise. I own a nice neutral blue dry suit that hopefully differentiates me from both pinnipeds and schools of fish.
Lastly, fins tend to be prime targets for bites. This is more likely to do with their movements and exposed position rather than colour but white, silver, or bright fins should probably be avoided.
3. Avoid erratic movements.
Sharks are able to pick up on disturbances in their environment. They are looking for the tell tale signature of a wounded fish or other animal. Once they find one they carry out their civic duty and remove the wounded creature from the gene pool. Thrashing around in the water may mimic the vibrations sent out by a wounded fish and/or may replicate the movements of a feeding shark. Either way, slow, rhythmic fin strokes are more likely to be ignored. Good buoyancy is also important. crashing into the reef or struggling to stay down could generate interest or may work in reverse and drive away sharks that you were hoping would stay around.
4. Look but don't touch.
The best way to get bitten by a shark is to grab it by the tail or any other part of its anatomy. You wouldn't think this needs putting into print but a surprising amount of shark bites are the direct result of divers trying to man handle otherwise docile creatures. Joe diver sees a nurse shark's tail protruding from under the reef and thinks that if he gives it a little poke or tug the nurse shark will shift into a position where Joe can get a better look at its head. He grabs the shark's tail and before he has time to register exactly what has happened he looks down to find a nurse shark jaw wrapped around his wrist. Contrary to popular belief, nurse sharks do have rows of sharp little teeth and once Joe is finally released (which sometimes doesn't happen until he is literally dragged out of the water) Joe gets to spend the rest of his holiday at the very least with a bandaged arm. Don't be Joe Diver. Sharks are extremely flexible and explosively fast.
Rays usually remain very docile if you approach them slowly until their personal space is encroached upon and then they finally either bolt or slowly lift off the bottom and relocate a few meters away. The best way to get near them is to move in close to the sea bed. Rays feel more threatened when approached from above.
In rays the two defence mechanisms that a diver needs to be aware of are: the stingrays tail barb, and the electric rays ability to shock.
Waders (often fishing) have been wounded and even killed where medical attention was not available as the result of stingray barbs entering the abdomen or other vital organs. The barbs often carry toxins which compound the medical problem and create immense pain. Luckily divers are rarely faced with stingrays using this defence mechanism as it is only employed as a last resort when the animal is pinned down. Stingrays are more than happy to move away if they are too closely approached by a diver. I am not aware of a single diver that has been stabbed whilst on a dive. This is not to say that you won't step on one with painful results whilst attempting a shore entry. If this occurs wash the wound in fresh water and apply as much heat to the area as possible. This will help to break down the toxins and relieve some of the pain. Seek medical attention as soon as possible. Stingray barbs often break up upon entry and the wound may need to be cut open and cleaned to avoid infection.
The electric organs of some rays are potentially dangerous but again in the majority of cases the ray is far more likely to move away than shock. However, torpedo rays are known to have a bad temper and there have been a few cases of these animals chasing divers and repeatedly shocking them. Some torpedo rays have been shown to be able to emit in excess of 200 volts! Usually if the animal is not harassed it will leave divers alone.
5. Stay away from the chum.
Sharks that come to a shark feed are not there to socialise. They want food and if you're between them and dinner you're in the wrong place at the wrong time. Keep your distance from any hanging bait that has been placed in the water and if the current is moving a chum slick away from the area make sure that you are positioned off to the side or up stream.
Having watched the shark's behaviour for some time you may feel confident about moving in for better pictures or a better look. Remember that if the current is running and you are down stream any sharks that are swimming up to the bait may think that those delicious odours are emanating from you. Now you're stuck in a position where a shark is coming toward you and you are drifting into it. As it's very hard to swim against even a mild current you probably now have to turn around to make headway against it to get back up stream which puts you with your back to the approaching shark. A better course of action is to swim sideways until clear of the chum slick at which point you can kick up current without looking like a fleeing wounded animal.
6. Get underwater.
Floating at the surface in the presence of sharks sends the wrong message. You want to descend as soon as you can for a few reasons:
Firstly, a body floating at the surface is high on the list of desirable objects for a shark to explore. In the ocean dead things float. Oily chum tends to create a slick on the surface that you may be covering yourself in while you remain there.
Secondly, if your head is above water you are effectively blind to the movements of any sharks underwater.
Thirdly, a positively buoyant diver's actions are far more limited. It takes time to become negative and descend out of trouble and swimming at the surface in dive gear looks an awful lot like a thrashing animal.
7. Read the sharks.
It's important to pay attention to the behaviour of the sharks participating in a feed. Although sharks become agitated as soon as they know food is available they will usually continue to cruise around calmly waiting for the opportunity to strike at the bait. In a well organized feed, access to the bait is often restricted to keep the sharks interested but not overexcited.
If too much bait ends up in the water, the sharks may become very aggressive. They may chase each other tearing at the food and in their single-mindedness any divers that get in the way stand a chance of getting hit. To understand the significance of being thumped by a shark underwater it's necessary to look at the medium the sharks are moving through. If an adrenalin filled dog were to hit you at 20 miles an hour it would bowl you down. Now replay this scenario in a medium 800 times denser than air and you don't get bowled over anymore because you're supported by the water. However, the object hitting you is still travelling at the same speed resulting in a tremendous impact. Even a leisurely swimming shark can hurt a diver but sharks rarely collide with anything unless they are panicked. Pay attention to the dynamics of the feed.
Beyond a critical level of excitement sharks may become too aggressive for divers to safely remain in the water, and it is difficult to judge when this point is approaching. If many sharks are in attendance and ploughing into the food, seemingly indifferent to anything else around them they may become excited enough to bite randomly at whatever is close to them. Often the surprising thing is how fast the pace can change.
Some sharks regardless of food stimulus may become aggressive towards divers. Any type of posturing is a bad sign. The threat display of Grey reef sharks has been well documented. This consists of exaggerated swimming motions, back arching, raising of the snout, lowering of the pectoral fins, and head swinging. Not all sharks will give you these visual cues but you may see some small modified behaviour. The message is a clear one: BACK OFF! Hopefully the diver will notice the posturing and move away before the shark takes its next defensive strategy which is often to attack. The most common scenario in which this situation occurs is when a shark is cornered. Try to always give sharks an escape route.
It may be tempting to want to photograph posturing behaviour but this has proven to be the downfall of numerous divers in the past. A camera flash is often the catalyst that brings on the final attack. Even bringing a camera up to eye level may be enough to push a shark over the edge and it's important to remember that no matter how ready you think you are, if a shark attacks at speed you are unlikely to be able to block the attack in time.
8. Be a responsible participant.
We have come a long way since the early days of Jacques Cousteau pitting himself against the monsters of the sea. The survival of the sharks that cruise today's oceans hangs in the balance. There is no excuse for harming any shark or even interrupting important behaviours such as mating or birthing. If you feel that a shark diving situation may require the use of a power head or other weapon for protection then the dive should not take place.
It is also important to protect the fragile environment that sharks and rays inhabit. "Getting the shot" is secondary to protecting the reef regardless of what the subject is. Always practice good buoyancy skills and if the situation calls for you to crouch inconspicuously on the sea floor find a barren spot that will not damage any corals or other marine creatures. That group of orange sponges may make for a better photo location but not at the expense of the surrounding corals.
If baiting sharks in to an area is enough to create a worthwhile experience, then actual feeding is not necessary. The consensus is that it is far more harmful and behaviour changing to actually feed sharks that to just lure them into the area.
Try to avoid creating a repetitive feeding area where resident sharks wait for a handout. Whilst this may be a convenient way to re-attract sharks it provides an easy target for unscrupulous shark fishers.
Diving with sharks can be a fun and highly rewarding activity but this becomes hollow and selfish enjoyment if you in any way harm the animals that you have come to see.
SHARK EVOLUTION
MISCONCEPTIONS AND INTERPRETATIONS
Source: http://elasmodiver.com/elasmobranch_evolution.htm
There are many misconceptions regarding the evolution of sharks and rays. Contrary to popular belief they have not remained unchanged for 300 million years. However, many of the families we have today have been in existence for perhaps the last 150 million years. Compared to our own paltry 3.5 million years this makes the elasmobranch lineage very ancient indeed. The fossil record is sketchy at best when it comes to sharks. Cartilage is preserved very poorly so the body structures of many early sharks are purely speculative. Fortunately for the paleontologists, sharks discard their teeth on a regular basis and these teeth which fossilize well are often enough to allow accurate identification of individual groups and help place them correctly in the evolutionary time line. One of the pitfalls of using fossilized teeth for identification is that the teeth of sharks sometimes vary significantly depending on which area of the jaw they have come from. In the past this has led to paleontologists inventing multiple species of extinct sharks that were actually the same animal. During a shark's lifetime it's dentition also may change which only adds to the confusion. In recent years there has been a revision of extinct species that paid more attention to the herero-dental nature of modern species, and consequently the list of extinct species has been paired down.
A WORLD BEFORE FISH...
How life first came about on earth is a burning question that many scientists and theologists have dedicated their entire careers to solving. Be it by chance or divine intervention, it is likely that super heated compounds developed a complexity at which point they were able to grow by absorbing the chemicals around them. Complex compounds are a far cry from even the most basic fishes but at some point (around 3.5 billion years ago) simple organisms started evolving. These most ancient forms of life on earth were called stromatolites and they may still be seen today. Stromatolites are simple organisms that cluster together and form mounds not unlike coral reefs but with a far less complex structure.
1.4 billion years later the first cells with a nucleus were ooching around looking for a way to take advantage of both the chemicals in their environment and each other. As is the nature of evolution, a radiation took place after this point that enabled these basic creatures to fill every niche that was available to them. By about 600 million years ago, multi-cellular organisms such as jellyfish, worms, sea-pens, and more obscure soft bodied invertebrates had taken over the ocean deserts.
540 million years ago near the beginning of the Phanerozoic Eon (which last to this day and is split into the Cambrian, Palaeozoic, Mesozoic, and Cenozoic Periods) Most of the modern groups of animals were developing. This era heralded the development of shelled creatures which have been preserved very well in the fossil record.
There is some conjecture regarding how primitive fishes managed to develop from these invertebrates. Most likely, fishes evolved from the larval forms of their predecessors. Most invertebrates release eggs and sperm which after combining, develop into free swimming, fish-like larvae. These larvae drift within the planktonic soup until they reach a point of metamorphosis. In many groups such as corals and tunicates this metamorphosis is highly dramatic, involving a complete restructuring of the body to adapt to a sessile lifestyle. However, if the planktonic environment were rich enough it would be prudent for some larvae to remain as free swimming organisms permanently. Which group of invertebrates are responsible for spawning the first fishes is not known but it is possible that it may have been the echinoderms (seastars and sea cucumbers) as they share an early cell developmental process with vertebrates. Some scientists believe that sea squirts are responsible. Recent fossil evidence also points to a now extinct animal called a conodont that was characteristically fish-like and may have been the true predecessor.
THE AGNATHA
Around 500 to 450 million years ago the first primitive fishes appeared in the fossil record. They were the Agnathans and they were characterized by two (dorsal and ventral) bony shields on the head with many trunk scales tapering towards a primitive caudal fin in which the notocord turned upwards rather like the sharks of today. Agnathans were very successful and diversified to dominate every niche available until well into the Devonian period towards the late Paleozoic. The various groups developed many of the characteristics associated with vertebrates today including: paired limbs, cellular bone, a complex sensory line system, dentine, and complex eyes and inner ears. Sadly these pioneers of all that represents our ancenstry, mostly vanished during the Devonian extinctions. Today the two remaining groups of agnatha are represented by the Hagfishes and Lampreys. They are jawless, limbless, and have cartilaginous skeletons.
THE RISE OF JAWED FISHES
At some point during the Ordovician Period also known as the early Paleozoic, the major groups separated themselves from eachother.
Between about 400 and 350 million years ago the seas were beginning to fill. The major groups were:
Osteichthyes - the bony fishes which eventually outnumbered all other vertebrates by species.
Crossopterygii - which split to form the Porolepiformes which evolved into salamanders and the Osteolepiformes which eventually evolved into frogs and toads, reptiles, birds, and mammals.
Dipnoans - the lungfishes
Acanthodians - also called the spiny sharks - Superficially shark like with strong broad spines strengthening all of their fins except the caudal fin which was upturned (heterocercal) as in the true sharks. Their bodies were covered with small flat bony scales. The Acanthodians survived into the early permian about 200 million years ago.
Placoderms - a large group of fishes covered with big bony plates and blade like jaws that proliferated during the Devonian and then died out at the beginning of the carboniferous period.
Chondrichthyes - the cartilaginous fishes that evolved into today's sharks, skates, rays, and chimaeras.
THE FIRST SHARK - Cladoselache
Although Chondrichthyes are rooted in the Ordovician period the first, well preserved early shark fossil to be discovered was Cladoselache dating from approximately 350 million years ago. The fossil of this shark was found miraculously intact in the Cleveland Shale of Lake Erie. It was so well preserved that its muscle fibers were visible as were its kidneys. Cladoselache Had two low dorsal fins both with prominent spines, broad based pectoral fins and eyes set far forward on the head. The mouth was at the front of the head as opposed to the under slung mouths of modern sharks, and the teeth had a large central pointed cusp with a smaller point on each side. Although cladoselache was almost certainly not the first ever true elasmobranch, armed with Cladoselache, Paleontologists were able to categorically state that elasmobranchs had arrived.
TWO VISIBLE SUBCLASSES
At the end of the Devonian another group of cartilaginous fish became evident. These fish known as Chimaeras or Ghost sharks had distinct mobility differences in their skeletal structure. The upper jaw was fused to the skull, the pectoral fins were large and able to flap unlike the rigid fins of sharks and their bodies tapered to a thin whip like tail. Due to the great distance between the chimaeras and the modern elasmobranchs, extant chimaeras are considered in the separate subclass Holocephali and presently consist of three families.
AN EXPLOSION OF FORMS
During the evolution of chrondrichthyes there have been many groups with bizarre appearances. Sometimes these families are collectively referred to as "paraselachians" . Many fossil skeletons contain unusual appendages. Most of which have as yet not been conclusively explained.
Some examples of these paraselachians include:
Stethacanthus - a Cladodont which lived through the Silurian Period between 380 and 300 million years ago. It had a modified first dorsal fin that terminated in a spine covered pad reminiscent of an inverted scrubbing brush. Its forehead also had a similar surface. These surfaces may have been used for pinning prey or for mating.
Helicoprion - from the Permian Period, had a conveyor belt of teeth that spiraled out of its lower jaw and a thin corresponding line of sharp teeth in the upper jaw. The lower whorl of teeth rotated out of the jaw as the shark grew. Unlike most sharks it retained the smaller previous teeth which rotated back into the jaw forming a spiral or whorl not unlike the growth pattern of a shell. The two dermal surfaces sliced against each other giving it a formidable shearing weapon.
Falcatus - from the carboniferous period had a curving, forward facing appendage in place of its first dorsal fin. It has been suggested that only the male may have had this sword like structure.
Xenacanthus - a member of the pleurocanthids. It had a long backward facing spike extending from the back of its skull and an eel like or ribbon like fin running down the length of its back.
Iniopteryx - Iniopterygians lived from the Devonian into the Carboniferous period. More closely related to modern day chimaeras, they had flexible pectoral fins which were disproportionately long and rayed for strength. It is unclear whether these "wings" were used to glide above the water or to paddle under it. The leading edge of the wings were covered with sharp toothy denticles.
Most of these evolutionary experiments were probably adaptations to the demands of life in an ever more competitive environment. During the Carboniferous Period the ranks of the sharks swelled to their greatest diversity ever but towards the beginning of the Permian Period many ancient forms became extinct along with the majority of the more experimental forms.
ENTER THE NEOSELACHIANS
As the Permian Period was drawing to a close the seas were filling with Actinopterygians - the ray finned fishes. This was a food source that could not be ignored by the oceans predators. In response the elasmobranchs began to radiate again and during the early Triassic a shark appeared in the fossil record that was similar enough in appearance to modern day sharks to be considered one of the first of the "modern sharks". The name of this shark was Palaeospinax.
Palaeospinax was morphologically similar to the dogfish of the family squalidae. It had a calcified sectioned vertebral column instead of a continuous notochord, its two dorsal fins had supportive leading edge spines, and most notably it had the under slung mouth of a modern shark.
NEOSELACHIAN RADIATION
Amongst the first of the presently extant sharks to swim in the seas were the slow swimming Horn sharks and the Cow sharks but towards the mid cretaceous the fair to be had in the mid oceans was enough to push the development of fast moving predators that could pick off large, schooling, off shore fishes. At the time the seas were ruled by enormous icthyosaurs and plesiosaurs so this new food source did not come without risk to the sharks.
During the Cretaceous most of the present genera were firmly established and then around 60 million years ago at the end of the Cretaceous a catastrophe occurred which wiped out the dinosaurs and many other species, leaving the remaining sharks as the supreme rulers of the oceans.
CARCHARODON MEGALODON
About 50 million years ago a super predator evolved, the size of which the world had not previously seen. Megalodon was similar in shape and dentition to the White shark (Carcharodon carcharias) the most notorious shark of today's temperate oceans. Its size however was spectacular. The largest of its fossilized teeth that have been found to date have measured over six inches long from point to base. Extrapolating this information and using Carcharodon carcharias as a guide, it would not be unreasonable to assume that Megalodon reached somewhere between 50 to 100 feet in length. Sadly but perhaps just as well for us, no Megalodon have been seen for some time. Estimates on the time of its extinction vary widely. Some popular literature would like us to believe that Megalodon is still down there somewhere lurking in the shadows. More likely Megalodon faded away some time within the last 30 million years due to a combination of a waning food supply and a changing climate.
RAY RADIATION
Meanwhile, back at the end of the Triassic, at about the same time as Palaeospinax was swimming around the coastline of the super continent Pangaea, another group of sharks were adapting well to the bottom terrain of the shallow slopes. By the upper Jurassic Period the first guitarfishes were grubbing around for food and blending into the bottom sediments. These rays were a little more primitive than those of today. The main differences being a more shark like skeletal structure and the presence of fin spines. It has been suggested that all modern rays were derived from primitive guitarfishes but it is unclear exactly where the families are linked. The most recent addition to the batoid tree are the stingrays which showed up a mere 60 million years ago yet fill the shallows of most tropical and temperate continental waters.
Source: http://elasmodiver.com/elasmobranch_evolution.htm
There are many misconceptions regarding the evolution of sharks and rays. Contrary to popular belief they have not remained unchanged for 300 million years. However, many of the families we have today have been in existence for perhaps the last 150 million years. Compared to our own paltry 3.5 million years this makes the elasmobranch lineage very ancient indeed. The fossil record is sketchy at best when it comes to sharks. Cartilage is preserved very poorly so the body structures of many early sharks are purely speculative. Fortunately for the paleontologists, sharks discard their teeth on a regular basis and these teeth which fossilize well are often enough to allow accurate identification of individual groups and help place them correctly in the evolutionary time line. One of the pitfalls of using fossilized teeth for identification is that the teeth of sharks sometimes vary significantly depending on which area of the jaw they have come from. In the past this has led to paleontologists inventing multiple species of extinct sharks that were actually the same animal. During a shark's lifetime it's dentition also may change which only adds to the confusion. In recent years there has been a revision of extinct species that paid more attention to the herero-dental nature of modern species, and consequently the list of extinct species has been paired down.
A WORLD BEFORE FISH...
How life first came about on earth is a burning question that many scientists and theologists have dedicated their entire careers to solving. Be it by chance or divine intervention, it is likely that super heated compounds developed a complexity at which point they were able to grow by absorbing the chemicals around them. Complex compounds are a far cry from even the most basic fishes but at some point (around 3.5 billion years ago) simple organisms started evolving. These most ancient forms of life on earth were called stromatolites and they may still be seen today. Stromatolites are simple organisms that cluster together and form mounds not unlike coral reefs but with a far less complex structure.
1.4 billion years later the first cells with a nucleus were ooching around looking for a way to take advantage of both the chemicals in their environment and each other. As is the nature of evolution, a radiation took place after this point that enabled these basic creatures to fill every niche that was available to them. By about 600 million years ago, multi-cellular organisms such as jellyfish, worms, sea-pens, and more obscure soft bodied invertebrates had taken over the ocean deserts.
540 million years ago near the beginning of the Phanerozoic Eon (which last to this day and is split into the Cambrian, Palaeozoic, Mesozoic, and Cenozoic Periods) Most of the modern groups of animals were developing. This era heralded the development of shelled creatures which have been preserved very well in the fossil record.
There is some conjecture regarding how primitive fishes managed to develop from these invertebrates. Most likely, fishes evolved from the larval forms of their predecessors. Most invertebrates release eggs and sperm which after combining, develop into free swimming, fish-like larvae. These larvae drift within the planktonic soup until they reach a point of metamorphosis. In many groups such as corals and tunicates this metamorphosis is highly dramatic, involving a complete restructuring of the body to adapt to a sessile lifestyle. However, if the planktonic environment were rich enough it would be prudent for some larvae to remain as free swimming organisms permanently. Which group of invertebrates are responsible for spawning the first fishes is not known but it is possible that it may have been the echinoderms (seastars and sea cucumbers) as they share an early cell developmental process with vertebrates. Some scientists believe that sea squirts are responsible. Recent fossil evidence also points to a now extinct animal called a conodont that was characteristically fish-like and may have been the true predecessor.
THE AGNATHA
Around 500 to 450 million years ago the first primitive fishes appeared in the fossil record. They were the Agnathans and they were characterized by two (dorsal and ventral) bony shields on the head with many trunk scales tapering towards a primitive caudal fin in which the notocord turned upwards rather like the sharks of today. Agnathans were very successful and diversified to dominate every niche available until well into the Devonian period towards the late Paleozoic. The various groups developed many of the characteristics associated with vertebrates today including: paired limbs, cellular bone, a complex sensory line system, dentine, and complex eyes and inner ears. Sadly these pioneers of all that represents our ancenstry, mostly vanished during the Devonian extinctions. Today the two remaining groups of agnatha are represented by the Hagfishes and Lampreys. They are jawless, limbless, and have cartilaginous skeletons.
THE RISE OF JAWED FISHES
At some point during the Ordovician Period also known as the early Paleozoic, the major groups separated themselves from eachother.
Between about 400 and 350 million years ago the seas were beginning to fill. The major groups were:
Osteichthyes - the bony fishes which eventually outnumbered all other vertebrates by species.
Crossopterygii - which split to form the Porolepiformes which evolved into salamanders and the Osteolepiformes which eventually evolved into frogs and toads, reptiles, birds, and mammals.
Dipnoans - the lungfishes
Acanthodians - also called the spiny sharks - Superficially shark like with strong broad spines strengthening all of their fins except the caudal fin which was upturned (heterocercal) as in the true sharks. Their bodies were covered with small flat bony scales. The Acanthodians survived into the early permian about 200 million years ago.
Placoderms - a large group of fishes covered with big bony plates and blade like jaws that proliferated during the Devonian and then died out at the beginning of the carboniferous period.
Chondrichthyes - the cartilaginous fishes that evolved into today's sharks, skates, rays, and chimaeras.
THE FIRST SHARK - Cladoselache
Although Chondrichthyes are rooted in the Ordovician period the first, well preserved early shark fossil to be discovered was Cladoselache dating from approximately 350 million years ago. The fossil of this shark was found miraculously intact in the Cleveland Shale of Lake Erie. It was so well preserved that its muscle fibers were visible as were its kidneys. Cladoselache Had two low dorsal fins both with prominent spines, broad based pectoral fins and eyes set far forward on the head. The mouth was at the front of the head as opposed to the under slung mouths of modern sharks, and the teeth had a large central pointed cusp with a smaller point on each side. Although cladoselache was almost certainly not the first ever true elasmobranch, armed with Cladoselache, Paleontologists were able to categorically state that elasmobranchs had arrived.
TWO VISIBLE SUBCLASSES
At the end of the Devonian another group of cartilaginous fish became evident. These fish known as Chimaeras or Ghost sharks had distinct mobility differences in their skeletal structure. The upper jaw was fused to the skull, the pectoral fins were large and able to flap unlike the rigid fins of sharks and their bodies tapered to a thin whip like tail. Due to the great distance between the chimaeras and the modern elasmobranchs, extant chimaeras are considered in the separate subclass Holocephali and presently consist of three families.
AN EXPLOSION OF FORMS
During the evolution of chrondrichthyes there have been many groups with bizarre appearances. Sometimes these families are collectively referred to as "paraselachians" . Many fossil skeletons contain unusual appendages. Most of which have as yet not been conclusively explained.
Some examples of these paraselachians include:
Stethacanthus - a Cladodont which lived through the Silurian Period between 380 and 300 million years ago. It had a modified first dorsal fin that terminated in a spine covered pad reminiscent of an inverted scrubbing brush. Its forehead also had a similar surface. These surfaces may have been used for pinning prey or for mating.
Helicoprion - from the Permian Period, had a conveyor belt of teeth that spiraled out of its lower jaw and a thin corresponding line of sharp teeth in the upper jaw. The lower whorl of teeth rotated out of the jaw as the shark grew. Unlike most sharks it retained the smaller previous teeth which rotated back into the jaw forming a spiral or whorl not unlike the growth pattern of a shell. The two dermal surfaces sliced against each other giving it a formidable shearing weapon.
Falcatus - from the carboniferous period had a curving, forward facing appendage in place of its first dorsal fin. It has been suggested that only the male may have had this sword like structure.
Xenacanthus - a member of the pleurocanthids. It had a long backward facing spike extending from the back of its skull and an eel like or ribbon like fin running down the length of its back.
Iniopteryx - Iniopterygians lived from the Devonian into the Carboniferous period. More closely related to modern day chimaeras, they had flexible pectoral fins which were disproportionately long and rayed for strength. It is unclear whether these "wings" were used to glide above the water or to paddle under it. The leading edge of the wings were covered with sharp toothy denticles.
Most of these evolutionary experiments were probably adaptations to the demands of life in an ever more competitive environment. During the Carboniferous Period the ranks of the sharks swelled to their greatest diversity ever but towards the beginning of the Permian Period many ancient forms became extinct along with the majority of the more experimental forms.
ENTER THE NEOSELACHIANS
As the Permian Period was drawing to a close the seas were filling with Actinopterygians - the ray finned fishes. This was a food source that could not be ignored by the oceans predators. In response the elasmobranchs began to radiate again and during the early Triassic a shark appeared in the fossil record that was similar enough in appearance to modern day sharks to be considered one of the first of the "modern sharks". The name of this shark was Palaeospinax.
Palaeospinax was morphologically similar to the dogfish of the family squalidae. It had a calcified sectioned vertebral column instead of a continuous notochord, its two dorsal fins had supportive leading edge spines, and most notably it had the under slung mouth of a modern shark.
NEOSELACHIAN RADIATION
Amongst the first of the presently extant sharks to swim in the seas were the slow swimming Horn sharks and the Cow sharks but towards the mid cretaceous the fair to be had in the mid oceans was enough to push the development of fast moving predators that could pick off large, schooling, off shore fishes. At the time the seas were ruled by enormous icthyosaurs and plesiosaurs so this new food source did not come without risk to the sharks.
During the Cretaceous most of the present genera were firmly established and then around 60 million years ago at the end of the Cretaceous a catastrophe occurred which wiped out the dinosaurs and many other species, leaving the remaining sharks as the supreme rulers of the oceans.
CARCHARODON MEGALODON
About 50 million years ago a super predator evolved, the size of which the world had not previously seen. Megalodon was similar in shape and dentition to the White shark (Carcharodon carcharias) the most notorious shark of today's temperate oceans. Its size however was spectacular. The largest of its fossilized teeth that have been found to date have measured over six inches long from point to base. Extrapolating this information and using Carcharodon carcharias as a guide, it would not be unreasonable to assume that Megalodon reached somewhere between 50 to 100 feet in length. Sadly but perhaps just as well for us, no Megalodon have been seen for some time. Estimates on the time of its extinction vary widely. Some popular literature would like us to believe that Megalodon is still down there somewhere lurking in the shadows. More likely Megalodon faded away some time within the last 30 million years due to a combination of a waning food supply and a changing climate.
RAY RADIATION
Meanwhile, back at the end of the Triassic, at about the same time as Palaeospinax was swimming around the coastline of the super continent Pangaea, another group of sharks were adapting well to the bottom terrain of the shallow slopes. By the upper Jurassic Period the first guitarfishes were grubbing around for food and blending into the bottom sediments. These rays were a little more primitive than those of today. The main differences being a more shark like skeletal structure and the presence of fin spines. It has been suggested that all modern rays were derived from primitive guitarfishes but it is unclear exactly where the families are linked. The most recent addition to the batoid tree are the stingrays which showed up a mere 60 million years ago yet fill the shallows of most tropical and temperate continental waters.
Whale shark
Common Names: Whale shark.Latin Name: Rhincodon Typus
Family: Rhincodontidae
Identification: Enormous size (worlds largest fish). Body scalloped (with two distinct ridges running from behind head along each flank into caudal fin. Pattern of white spots and indistinct lines on grey dorsum. Ventrum white or pale. First dorsal large. Caudal large. Mouth terminal and often open when observed feeding on plankton.
Size: Maximum length 18m (unconfirmed) reliably to 16m.
Habitat: Pelagic. Comes into reef areas when food supply is abundant e.g. coral spawning.
Habitat: Pelagic. Comes into reef areas when food supply is abundant e.g. coral spawning.
Abundance and distribution: Circumtropical except Mediterranean.
Behavior: Usually seen swimming with mouth agape in feeding mode. Little is known about the Whale sharks biology or migratory patterns.
Reproduction: Ovoviviparous. Previously thought to be oviparous due to an eggcase containing a Whale shark embryo dredge from the bottom of the sea. This perception changed in 1995 when a Taiwanese fishing boat harpooned an 8m female containing 300 embryos. Whale sharks have been observed at Ningaloo performing figure 8 maneuvers while nose to tail. It has been speculated that this may be some form of courting behavior.
Observations:
Photographs: Ningaloo Reef, Western Australia.
Similar species:
Reaction to divers: Whale sharks generally move away from the noise creatred by scuba bubbles and from physical contact. Getting too close to a whale shark often causes it to dive and 'riding' the sharks interferes with their natural behavior and should be discoraged even if local rules are very liberal. The best encounters tend to be on scuba.
Reaction to divers: Whale sharks generally move away from the noise creatred by scuba bubbles and from physical contact. Getting too close to a whale shark often causes it to dive and 'riding' the sharks interferes with their natural behavior and should be discoraged even if local rules are very liberal. The best encounters tend to be on scuba.
Diving logistics: Operators around the world run Whale shark encounters. Some use spotter planes while others rely on the sharks returning to well known feeding sites. Ningaloo Reef encounters are very predicable and the customers generally get a few sharks each day during the season. For more information on Ningaloo go to the Exmouth / Ningaloo page in the Shark diving hotspots section of Elasmodiver or follow the link here.
Marine Biology Degree Programs in the U.S.
Marine Biology Degree Programs in the U.S.
The following is our list of all U.S. schools that offer degrees in Marine Biology. All links open in a new window linking directly to each school's marine biology program. To determine which school is right for you, you may want to consult the current rankings, but be forewarned that they are not always the best indicator of the "best" school. It is often better to make your own assessment based on the school's curricula, the experience of its faculty, and good laboratory facilities for hands on experience. To browse through a list of research facilities, click here. » Download the 256 page Admission Guide created by Franziska Elmer from Switzerland (700KB) - contains addresses, contact, student residential and program information as well as admission details for international students interested in Marine Biology degrees in the U.S. Thank you Franziska!
Contact us if you have any comments, changes or additions.
International Marine Biology Degree Programs »
Alabama
Alabama State University BS
Auburn University BS, MS, PhD
Samford University BS
Tuskegee University BS
University of Alabama BS, MS
University of North Alabama BS
University of South Alabama MS, PhD
University of West Alabama BS
Alaska Alaska Pacific University BS
University of Alaska Fairbanks MS, PhD
University of Alaska Southeast BS
California
California Lutheran University BA
California State University, Long Beach BS, MS
California State University (Moss Landing Marine Laboratories) MS
California State University Monterey Bay BS, MS
Humboldt State University BS, MS
San Diego State University BS
San Francisco State University BS, MA
San Jose State University BS
Sonoma State University BS
University of California Berkeley BS, MS, PhD
University of California Los Angeles BS
University of California Santa Barbara BS, MS, PhD
University of California Santa Cruz BS
Univ of California San Diego (Scripps Institution of Oceanography)University of San Diego BA, MS in Marine Science
University of Southern California PhD
Connecticut
University of New Haven BS
University of Connecticut BS, BA
Florida Barry University BS
Eckerd College BS
Florida Atlantic University BS, MS
Florida Institute of Technology BS, MS, PhD
Florida International University BS
Florida Keys Community College AS
Florida State University BS
Jacksonville University BS
Nova Southeastern University BS, MS, PhD
Stetson University BS
University of Florida: Fisheries/Aquatic Sciences (FAS) BS, MS, PhD
University of Miami: Rosenstiel School of Marine & Atmospheric Science BS, MA, MS, PhD
University of South Florida BS, MS, PhD
University of Tampa BS
University of West Florida BS
Georgia
University of Georgia BS, MS, PhD
Hawaii
Hawaii Pacific University BS
University of Hawaii Hilo BS
University of Hawaii - Hawaii Institute of Marine Biology BS
Kansas
Southwestern College BS
Louisiana
Nicholls State University BS, MS
Maine
Maine Maritime Academy BS
Unity College BS
University of Maine BS, MS, PhD
University of Maine Machias BS
University of New England BS
Maryland
University of Maryland MS, PhD
Massachusetts
Boston University MA, PhD
Hampshire College BS
Harvard College summer program only
Salem State College BS
Suffolk University BS
University of Massachusetts Darmouth BS
Mississippi
University of Southern Mississippi Coastal Science MS, PhD
University of Southern Mississippi Marine Science BS, MS, PhD
New Hampshire
University of New Hampshire - Marine Program BS, MS, PhD
New Jersey
Fairleigh Dickinson University BS
Richard Stockton College of New Jersey BS
Rutgers BS, MS, PhD
New York
Hofstra University BA, MA, MS
Long Island University, Southampton College BS, BA
State University of New York BS
State University of New York - Stony Brook BS, MS, PhD
North Carolina
Duke University BS, MEM (Master of Environmental Management), PhDUniversity of North Carolina Chapel Hill MS, PhD
University of North Carolina Wilmington BS, MS, PhD
Ohio
Bowling Green State University (BGSU) Aquatic and Marine Science BS Biology with an emphasis in marine and freshwater science
Ohio University BS
Oregon
University of Oregon BS(eMB), MS, PhD
Pennsylvania
Bloomsburg University BS
East Stroudsburg University of Pennsylvania BS
Puerto Rico University of Puerto Rico Hunacao BS
University of Puerto Rico Myaguez Campus MS, PhD
Rhode Island
Roger Williams University BS, BA
University of Rhode Island BS
South Carolina
Coastal Carolina University BS, MS
College of Charleston BS, MS
Medical University of South Carolina MS
University of South Carolina BS, MS, PhD
Texas
Texas A&M University Corpus Christi BS, MS
Texas A&M University Galveston BS, MS
University of Texas at Austin BS
Virginia
College of William and Mary MS, PhD
Hampton University BS
Old Dominion University BS, MS, PhD
Washington
Seattle Pacific University BA, BS
University of Washington: Marine Biology BS
University of Washington: School of Aquatic and Fishery Science BS, MS, PhD
Western Washington University BS, MS
Wisconsin
Carroll College BS
Lawrence University BS
University of Wisconsin Superior BS
Graduate School Directory for Marine Sciences »
« Back to MarineBio Education & Career Resources
The following is our list of all U.S. schools that offer degrees in Marine Biology. All links open in a new window linking directly to each school's marine biology program. To determine which school is right for you, you may want to consult the current rankings, but be forewarned that they are not always the best indicator of the "best" school. It is often better to make your own assessment based on the school's curricula, the experience of its faculty, and good laboratory facilities for hands on experience. To browse through a list of research facilities, click here. » Download the 256 page Admission Guide created by Franziska Elmer from Switzerland (700KB) - contains addresses, contact, student residential and program information as well as admission details for international students interested in Marine Biology degrees in the U.S. Thank you Franziska!
Contact us if you have any comments, changes or additions.
International Marine Biology Degree Programs »
Alabama
Alabama State University BS
Auburn University BS, MS, PhD
Samford University BS
Tuskegee University BS
University of Alabama BS, MS
University of North Alabama BS
University of South Alabama MS, PhD
University of West Alabama BS
Alaska Alaska Pacific University BS
University of Alaska Fairbanks MS, PhD
University of Alaska Southeast BS
California
California Lutheran University BA
California State University, Long Beach BS, MS
California State University (Moss Landing Marine Laboratories) MS
California State University Monterey Bay BS, MS
Humboldt State University BS, MS
San Diego State University BS
San Francisco State University BS, MA
San Jose State University BS
Sonoma State University BS
University of California Berkeley BS, MS, PhD
University of California Los Angeles BS
University of California Santa Barbara BS, MS, PhD
University of California Santa Cruz BS
Univ of California San Diego (Scripps Institution of Oceanography)University of San Diego BA, MS in Marine Science
University of Southern California PhD
Connecticut
University of New Haven BS
University of Connecticut BS, BA
Florida Barry University BS
Eckerd College BS
Florida Atlantic University BS, MS
Florida Institute of Technology BS, MS, PhD
Florida International University BS
Florida Keys Community College AS
Florida State University BS
Jacksonville University BS
Nova Southeastern University BS, MS, PhD
Stetson University BS
University of Florida: Fisheries/Aquatic Sciences (FAS) BS, MS, PhD
University of Miami: Rosenstiel School of Marine & Atmospheric Science BS, MA, MS, PhD
University of South Florida BS, MS, PhD
University of Tampa BS
University of West Florida BS
Georgia
University of Georgia BS, MS, PhD
Hawaii
Hawaii Pacific University BS
University of Hawaii Hilo BS
University of Hawaii - Hawaii Institute of Marine Biology BS
Kansas
Southwestern College BS
Louisiana
Nicholls State University BS, MS
Maine
Maine Maritime Academy BS
Unity College BS
University of Maine BS, MS, PhD
University of Maine Machias BS
University of New England BS
Maryland
University of Maryland MS, PhD
Massachusetts
Boston University MA, PhD
Hampshire College BS
Harvard College summer program only
Salem State College BS
Suffolk University BS
University of Massachusetts Darmouth BS
Mississippi
University of Southern Mississippi Coastal Science MS, PhD
University of Southern Mississippi Marine Science BS, MS, PhD
New Hampshire
University of New Hampshire - Marine Program BS, MS, PhD
New Jersey
Fairleigh Dickinson University BS
Richard Stockton College of New Jersey BS
Rutgers BS, MS, PhD
New York
Hofstra University BA, MA, MS
Long Island University, Southampton College BS, BA
State University of New York BS
State University of New York - Stony Brook BS, MS, PhD
North Carolina
Duke University BS, MEM (Master of Environmental Management), PhDUniversity of North Carolina Chapel Hill MS, PhD
University of North Carolina Wilmington BS, MS, PhD
Ohio
Bowling Green State University (BGSU) Aquatic and Marine Science BS Biology with an emphasis in marine and freshwater science
Ohio University BS
Oregon
University of Oregon BS(eMB), MS, PhD
Pennsylvania
Bloomsburg University BS
East Stroudsburg University of Pennsylvania BS
Puerto Rico University of Puerto Rico Hunacao BS
University of Puerto Rico Myaguez Campus MS, PhD
Rhode Island
Roger Williams University BS, BA
University of Rhode Island BS
South Carolina
Coastal Carolina University BS, MS
College of Charleston BS, MS
Medical University of South Carolina MS
University of South Carolina BS, MS, PhD
Texas
Texas A&M University Corpus Christi BS, MS
Texas A&M University Galveston BS, MS
University of Texas at Austin BS
Virginia
College of William and Mary MS, PhD
Hampton University BS
Old Dominion University BS, MS, PhD
Washington
Seattle Pacific University BA, BS
University of Washington: Marine Biology BS
University of Washington: School of Aquatic and Fishery Science BS, MS, PhD
Western Washington University BS, MS
Wisconsin
Carroll College BS
Lawrence University BS
University of Wisconsin Superior BS
Graduate School Directory for Marine Sciences »
« Back to MarineBio Education & Career Resources
Thursday, February 7, 2008
Hawaii's coral reefs
Hawaii's coral reefs and nearshore waters are home to more than 7,000 forms of marine life, a quarter of them found nowhere else on Earth. Hawaii’s reefs contribute more than $360 million annually to the state’s economy – that’s $1 million a day.
These reefs are truly a global ocean treasure. Hawai'i has...
More unique marine species than any place of its size in the tropics
One of the last large-scale marine wilderness areas on the planet
Over 300,000 acres of nearshore coral reef
The Nature Conservancy launched its Hawai‘i Marine Program in 2002 to help preserve the Islands’ remarkable marine diversity. The Conservancy’s efforts are focused on restoring the health of our magnificent coral reefs and the unique species that depend on them for their survival.
A Resource at Risk
Despite their biological, economic, and cultural importance, Hawaii’s marine ecosystems continue to be severely degraded by human activity. With a resident population of 1.3 million and 7 million visitors arriving annually – the majority of whom engage in ocean-related activities – Hawaii’s reefs are strained beyond capacity.
The reality is that our ocean faces serious threats, most caused by humans, that have upset the delicate balance of life beneath the waves. Overfishing, the use of indiscriminate fishing practices such as lay gill nets, pollution, runoff, inappropriate recreational use, and the introduction and spread of invasive alien species all jeopardize the health of our reefs.
The good news is that reefs are resilient – if we act in time, we can restore them.
What The Conservancy Is Doing
We are working in collaboration with others to rescue Hawaii's coral reefs – our rainforests of the ocean – from further degradation. Major ongoing efforts include:
Community-based partnerships and programs
Invasive species removal
Reef Fund
Fair Catch responsible fishing campaign
Labels:
Advance Scuba training, Adventure Sports, Basic Open Water, Digital Underwater Photography, Extreme Scuba and Jason Kilgore, family travel, sharks, discount travel, Enriched Air, Hawaii Scuba Diving, Hawaiian Islands sight seeing, ITAN, Kona, NAUI, NOAA, other specialty certifications, sharks, SSI, TDI/SDI, airlines, family travel, family vacations, Hawaii reef divers, Hawaiian Islands, hotels, Jason Kilgore, Maui, scuba certification, scuba diving, scuba rental gear, Scuba Hawaii, Hawaii Travel, Caribbean Scuba, Scuba Certification, Scuba Jay
These reefs are truly a global ocean treasure. Hawai'i has...
More unique marine species than any place of its size in the tropics
One of the last large-scale marine wilderness areas on the planet
Over 300,000 acres of nearshore coral reef
The Nature Conservancy launched its Hawai‘i Marine Program in 2002 to help preserve the Islands’ remarkable marine diversity. The Conservancy’s efforts are focused on restoring the health of our magnificent coral reefs and the unique species that depend on them for their survival.
A Resource at Risk
Despite their biological, economic, and cultural importance, Hawaii’s marine ecosystems continue to be severely degraded by human activity. With a resident population of 1.3 million and 7 million visitors arriving annually – the majority of whom engage in ocean-related activities – Hawaii’s reefs are strained beyond capacity.
The reality is that our ocean faces serious threats, most caused by humans, that have upset the delicate balance of life beneath the waves. Overfishing, the use of indiscriminate fishing practices such as lay gill nets, pollution, runoff, inappropriate recreational use, and the introduction and spread of invasive alien species all jeopardize the health of our reefs.
The good news is that reefs are resilient – if we act in time, we can restore them.
What The Conservancy Is Doing
We are working in collaboration with others to rescue Hawaii's coral reefs – our rainforests of the ocean – from further degradation. Major ongoing efforts include:
Community-based partnerships and programs
Invasive species removal
Reef Fund
Fair Catch responsible fishing campaign
Labels:
Advance Scuba training, Adventure Sports, Basic Open Water, Digital Underwater Photography, Extreme Scuba and Jason Kilgore, family travel, sharks, discount travel, Enriched Air, Hawaii Scuba Diving, Hawaiian Islands sight seeing, ITAN, Kona, NAUI, NOAA, other specialty certifications, sharks, SSI, TDI/SDI, airlines, family travel, family vacations, Hawaii reef divers, Hawaiian Islands, hotels, Jason Kilgore, Maui, scuba certification, scuba diving, scuba rental gear, Scuba Hawaii, Hawaii Travel, Caribbean Scuba, Scuba Certification, Scuba Jay
Tuesday, February 5, 2008
“Six Degrees Could Change the World”
A new documentary titled “Six Degrees Could Change the World” will be airing on the National Geographic Channel on Sunday 10 February at 8pm ET.
The program, based on a book by the same title by Mark Lymas, sounds like scenes from a dramatic “The Day After” style disaster movie: from 1 degree of temperature increase: “residents flee midwest drought” “alpine villages threatened by frequent rockfalls” “mass bleaching of coral spreads, scientists warn of ecological impact” “hurricane expected to hit Mediterranean coast”… to 6 degrees of temperature increase:
“emergency alert system disbanded” “communications sporadic as major infrastructures collapse” “ocean’s surface becomes poisonous” “cities and towns unsustainable”
The book and documentary are based on the estimation that, during the last 100 years, global warming has increased by about .07 degrees Celsius or 1.2 degrees Farenheit. According to the UN Intergovernmental Panel on Climate Change (IPCC), at no other time in the past 1,300 years has our planet been as warm as it is now. Temperature records from the deep ocean suggest that temperatures are now within a degree of their highest levels in 1 million years.
The IPCC estimates that Earth will continue to increase in temperature between 1.4-5.8 degrees Celsius by the end of this century. Though six degrees doesn’t sound like a lot, it’s enough to alter the world as we know it in a devastating way. Much of life will be destroyed. The signs are already there - the snows of Kilimanjaro are melting, glaciers on the Matterhorn in the Alps are melting and releasing huge boulders, and atoll nations in the Pacific are disappearing inch by inch under the water as it rises due to global warming.
This documentary and book describe in vivid detail what will happen if global warming continues unchecked. Check them out! Sunday 10 February at 8pm ET
Keywords:
Advance Scuba training, Adventure Sports, Basic Open Water, Digital Underwater Photography, Extreme Scuba and Jason Kilgore, family travel, sharks, discount travel, Enriched Air, Hawaii Scuba Diving, Hawaiian Islands sight seeing, ITAN, Kona, NAUI, NOAA, other specialty certifications, sharks, SSI, TDI/SDI, airlines, family travel, family vacations, Hawaii reef divers, Hawaiian Islands, hotels, Jason Kilgore, Maui, scuba certification, scuba diving, scuba rental gear, Scuba Hawaii, Hawaii Travel, Caribbean Scuba, Scuba Certification, Scuba Jay, Costa Maya Scuba Dive, Gear, Cave Diving, TDI, Water Rescue Diving, Water Rescues, PADI Technical Scuba Diving, Dive Rescue, Scuba Dive Answers, Jason Kilgore and Martial Arts, Jason Kilgore and USANA, Jason Kilgore and Karate, Jason Kilgore and Scuba Diving, Sacramento, auburn, California, Hawaii, Jason Kilgore and Sierra Foothills Karate, Sierra Foothills Karate and Scuba Diving, Jason Kilgore and Scuba Diving, snorkel and fins, vacation, Basic Open Water, Extreme Scuba and Jason Kilgore, Hawaiian Islands, PADI Divemaster SCUBA Certification, Snorkel Bob, Snorkeling/Fin, TDI/SDI, Underwater Instructors, airlines, Divemaster scuba, family vacations, Reef Relief, coral reef, reef fish, maui divers, dive shops, scuba dive shops, cave diving, ice diving, wreck diving, Shark Diving, Shark Exploration, Baja, South America, vacation, Scuba and Jason Kilgore, Naui and Jason Kilgore, How to scuba dive?, skin diving, snorkel, mask, fins, sight seeing, hotels, Jason Kilgore and Hawaiian islands, Kona, Maui, other specialty certifications, Ocean Conservancy, International Coastal Cleanup, Costa Maya Hotel, Mexico Hotels, Mexico Scuba Diving, Diving in South American Scuba, Crabs, Sea Slugs, Marine Animals, Wildlife, Florida, Southern States, Marine Life, Pacific States, Pacific Northwestern States, California
The program, based on a book by the same title by Mark Lymas, sounds like scenes from a dramatic “The Day After” style disaster movie: from 1 degree of temperature increase: “residents flee midwest drought” “alpine villages threatened by frequent rockfalls” “mass bleaching of coral spreads, scientists warn of ecological impact” “hurricane expected to hit Mediterranean coast”… to 6 degrees of temperature increase:
“emergency alert system disbanded” “communications sporadic as major infrastructures collapse” “ocean’s surface becomes poisonous” “cities and towns unsustainable”
The book and documentary are based on the estimation that, during the last 100 years, global warming has increased by about .07 degrees Celsius or 1.2 degrees Farenheit. According to the UN Intergovernmental Panel on Climate Change (IPCC), at no other time in the past 1,300 years has our planet been as warm as it is now. Temperature records from the deep ocean suggest that temperatures are now within a degree of their highest levels in 1 million years.
The IPCC estimates that Earth will continue to increase in temperature between 1.4-5.8 degrees Celsius by the end of this century. Though six degrees doesn’t sound like a lot, it’s enough to alter the world as we know it in a devastating way. Much of life will be destroyed. The signs are already there - the snows of Kilimanjaro are melting, glaciers on the Matterhorn in the Alps are melting and releasing huge boulders, and atoll nations in the Pacific are disappearing inch by inch under the water as it rises due to global warming.
This documentary and book describe in vivid detail what will happen if global warming continues unchecked. Check them out! Sunday 10 February at 8pm ET
Keywords:
Advance Scuba training, Adventure Sports, Basic Open Water, Digital Underwater Photography, Extreme Scuba and Jason Kilgore, family travel, sharks, discount travel, Enriched Air, Hawaii Scuba Diving, Hawaiian Islands sight seeing, ITAN, Kona, NAUI, NOAA, other specialty certifications, sharks, SSI, TDI/SDI, airlines, family travel, family vacations, Hawaii reef divers, Hawaiian Islands, hotels, Jason Kilgore, Maui, scuba certification, scuba diving, scuba rental gear, Scuba Hawaii, Hawaii Travel, Caribbean Scuba, Scuba Certification, Scuba Jay, Costa Maya Scuba Dive, Gear, Cave Diving, TDI, Water Rescue Diving, Water Rescues, PADI Technical Scuba Diving, Dive Rescue, Scuba Dive Answers, Jason Kilgore and Martial Arts, Jason Kilgore and USANA, Jason Kilgore and Karate, Jason Kilgore and Scuba Diving, Sacramento, auburn, California, Hawaii, Jason Kilgore and Sierra Foothills Karate, Sierra Foothills Karate and Scuba Diving, Jason Kilgore and Scuba Diving, snorkel and fins, vacation, Basic Open Water, Extreme Scuba and Jason Kilgore, Hawaiian Islands, PADI Divemaster SCUBA Certification, Snorkel Bob, Snorkeling/Fin, TDI/SDI, Underwater Instructors, airlines, Divemaster scuba, family vacations, Reef Relief, coral reef, reef fish, maui divers, dive shops, scuba dive shops, cave diving, ice diving, wreck diving, Shark Diving, Shark Exploration, Baja, South America, vacation, Scuba and Jason Kilgore, Naui and Jason Kilgore, How to scuba dive?, skin diving, snorkel, mask, fins, sight seeing, hotels, Jason Kilgore and Hawaiian islands, Kona, Maui, other specialty certifications, Ocean Conservancy, International Coastal Cleanup, Costa Maya Hotel, Mexico Hotels, Mexico Scuba Diving, Diving in South American Scuba, Crabs, Sea Slugs, Marine Animals, Wildlife, Florida, Southern States, Marine Life, Pacific States, Pacific Northwestern States, California
Kaaihue Brothers
We Snorkel With Turtles ? On Every Tour!! We travel the South Shore of Kauai; the islands best snorkeling year round and best whale watching (December - May)! Poipu, also known as ?Sunny Poipu? or locally as the South Side, is located only about 20 minutes from the airport in Lihue. With virtually no runoffs or streams, the visibility is exceptional and not affected by rainfall. Most of our tour is spent snorkeling with turtles, exotic fish and various sea life. We snorkel at least 2 locations and give you a guided tour through the water, pointing out eels, lobster, octopus, etc.
The surf on the south side is minimal. The large swells that hit our island in the winter months only affect the north and west shores? not the south! Therefore, if you’re planning on snorkeling on your vacation, or just want to join us for exceptional whale watching, be sure to go with Kaaihue Brothers.
Keywords:
Advance Scuba training, Adventure Sports, Basic Open Water, Digital Underwater Photography, Extreme Scuba and Jason Kilgore, family travel, sharks, discount travel, Enriched Air, Hawaii Scuba Diving, Hawaiian Islands sight seeing, ITAN, Kona, NAUI, NOAA, other specialty certifications, sharks, SSI, TDI/SDI, airlines, family travel, family vacations, Hawaii reef divers, Hawaiian Islands, hotels, Jason Kilgore, Maui, scuba certification, scuba diving, scuba rental gear, Scuba Hawaii, Hawaii Travel, Caribbean Scuba, Scuba Certification, Scuba Jay, Costa Maya Scuba Dive, Gear, Cave Diving, TDI, Water Rescue Diving, Water Rescues, PADI Technical Scuba Diving, Dive Rescue, Scuba Dive Answers, Jason Kilgore and Martial Arts, Jason Kilgore and USANA, Jason Kilgore and Karate, Jason Kilgore and Scuba Diving, Sacramento, auburn, California, Hawaii, Jason Kilgore and Sierra Foothills Karate, Sierra Foothills Karate and Scuba Diving, Jason Kilgore and Scuba Diving, snorkel and fins, vacation, Basic Open Water, Extreme Scuba and Jason Kilgore, Hawaiian Islands, PADI Divemaster SCUBA Certification, Snorkel Bob, Snorkeling/Fin, TDI/SDI, Underwater Instructors, airlines, Divemaster scuba, family vacations, Reef Relief, coral reef, reef fish, maui divers, dive shops, scuba dive shops, cave diving, ice diving, wreck diving, Shark Diving, Shark Exploration, Baja, South America, vacation, Scuba and Jason Kilgore, Naui and Jason Kilgore, How to scuba dive?, skin diving, snorkel, mask, fins, sight seeing, hotels, Jason Kilgore and Hawaiian islands, Kona, Maui, other specialty certifications, Ocean Conservancy, International Coastal Cleanup, Costa Maya Hotel, Mexico Hotels, Mexico Scuba Diving, Diving in South American Scuba, Crabs, Sea Slugs, Marine Animals, Wildlife, Florida, Southern States, Marine Life, Pacific States, Pacific Northwestern States, California
The surf on the south side is minimal. The large swells that hit our island in the winter months only affect the north and west shores? not the south! Therefore, if you’re planning on snorkeling on your vacation, or just want to join us for exceptional whale watching, be sure to go with Kaaihue Brothers.
Keywords:
Advance Scuba training, Adventure Sports, Basic Open Water, Digital Underwater Photography, Extreme Scuba and Jason Kilgore, family travel, sharks, discount travel, Enriched Air, Hawaii Scuba Diving, Hawaiian Islands sight seeing, ITAN, Kona, NAUI, NOAA, other specialty certifications, sharks, SSI, TDI/SDI, airlines, family travel, family vacations, Hawaii reef divers, Hawaiian Islands, hotels, Jason Kilgore, Maui, scuba certification, scuba diving, scuba rental gear, Scuba Hawaii, Hawaii Travel, Caribbean Scuba, Scuba Certification, Scuba Jay, Costa Maya Scuba Dive, Gear, Cave Diving, TDI, Water Rescue Diving, Water Rescues, PADI Technical Scuba Diving, Dive Rescue, Scuba Dive Answers, Jason Kilgore and Martial Arts, Jason Kilgore and USANA, Jason Kilgore and Karate, Jason Kilgore and Scuba Diving, Sacramento, auburn, California, Hawaii, Jason Kilgore and Sierra Foothills Karate, Sierra Foothills Karate and Scuba Diving, Jason Kilgore and Scuba Diving, snorkel and fins, vacation, Basic Open Water, Extreme Scuba and Jason Kilgore, Hawaiian Islands, PADI Divemaster SCUBA Certification, Snorkel Bob, Snorkeling/Fin, TDI/SDI, Underwater Instructors, airlines, Divemaster scuba, family vacations, Reef Relief, coral reef, reef fish, maui divers, dive shops, scuba dive shops, cave diving, ice diving, wreck diving, Shark Diving, Shark Exploration, Baja, South America, vacation, Scuba and Jason Kilgore, Naui and Jason Kilgore, How to scuba dive?, skin diving, snorkel, mask, fins, sight seeing, hotels, Jason Kilgore and Hawaiian islands, Kona, Maui, other specialty certifications, Ocean Conservancy, International Coastal Cleanup, Costa Maya Hotel, Mexico Hotels, Mexico Scuba Diving, Diving in South American Scuba, Crabs, Sea Slugs, Marine Animals, Wildlife, Florida, Southern States, Marine Life, Pacific States, Pacific Northwestern States, California
Friday, January 25, 2008
Philippines Scuba
Dive Instructor Thierry left Mexico last year and went off on an extensive journey to explore the Philippines. Here is a photo essay of his trip.
The Philippines is an archipelago consisting of 7,107 islands. They separate the Celebes Sea and the South China Sea from the Pacific OceanThe archipelago is the second-largest in the world after Indonesia.
The warm, clear waters of the Philippines are known to contain some of the most diverse and beautiful marine life to be found anywhere in the world. Its waters are home to more than 3000 species of fish and 448 species of coral (compared to 700 species of fish and 100 species of coral in the entire Caribbean). But there have also been a lot of mixed reports on the destructive aftermath of dynamite fishing. Many visitors return from the Phillippines dissapointed divers because they didn't encounter the abundant marine life and healthy reefs others talk so enthusiastically about. Although some of the world's most extensive coral reefs are found in the Philippines, they are under such sustained assault by dynamite fishing that marine biologists say the corals are on the verge of utter collapse.
"There are many horrific things going on in the world's oceans, but this tops the list," said John McCosker, the chairman of aquatic biology at the California Academy of Sciences in San Francisco. "When divers talked about the world's finest coral reefs 20 years ago, the consensus for the top spot was always the Philippines, but nobody feels that way now." Read more here...
A member of the Dive Global team snorkeled off Boracay island 20 years ago and remembered the reefs looking quite healthy back then. We were curious to find out from Thierry what his general impression was and if it still is a country worthwhile going to for scuba divers. Thierry visited quite a few islands during his stay and traveled by air, bus, ferry, banca (the traditional outrigger boat) and the famous Jeepny to get to the different places on his itinerary. A jeepny, for those of you that don’t know, is a US military vehicle left there in the Second World War. The jeeps have taken on a life of their own. Over the years, the Philippines have decorated these vehicles to their hearts content. You find them everywhere as a local means of transportation and they are considered a national symbol of the country.
Generally speaking, dive sites in the Philippines are known to include walls and drop-offs, coral gardens, drift dives and many rare and truly unique creatures including huge numbers of riggerfish, parrotfish, pennant fish, moray eels, surgeonfish, snappers, groupers, moorish idol, lizardfish, gobies, batfish, lionfish, trumpetfish, pufferfish, filefish, emperors, wrasses, fusiliers and trevallies. Invertebrates from the tiniest transparent shrimp and neon-colored nudibranchs to huge basket sponges adorned with hundreds of multi-colored crinoids can be found.
Anemones, sea cucumbers, starfish and worms reside with vast numbers of hard and soft corals and gorgonian sea fans. Turtles, octopus, cuttlefish, manta rays, eagle rays and sharks make guest appearances in certain areas.Palawan, which is south of Luzon, is considered the best (commercialized) diving destination in the Philippines. Shipwrecks abound in Coron, while excellent coral formations can be found in El Nido. Apo Island and the Tubbataha Reefs, to name a few, are still considered coral paradises.However, if you prefer to stay near Manila, you can go on a day trip to either Batangas (Anilao or Nasugbu) or Mindoro (Puerto Galera). Boracay is also very popular and easy to reach by a direct flight from Manila. It offers some amazing drift dives on walls and the beaches as positively stunning!
The island has become more commercialized over the years however and isn't as idyllic as it used to be.Thierry had an amazing time and even though he experienced some great dives in other locations, the highlight of his trip definitely was a visit to Malapascua Island which is known for a dive location where regular encounters with thresher sharks are pretty much guaranteed. Malapascua Island is in the Visayan Sea and belongs to Cebu. Cebu is easy to reach but this area has not yet been over-commercialized in diving terms and is considered one of the better exciting and off-the-beaten track diving destinations in the Philippines.
Keywords:
Advance Scuba training, Adventure Sports, airlines, Basic Open Water, Digital Underwater Photography, discount travel, Divemaster scuba, Enriched Air, Extreme Scuba and Jason Kilgore, family travel, family vacations, Hawaii reef divers, Hawaii Scuba Diving, Hawaiian Islands, Hawaiian Islands sight seeing, hotels, Jason Kilgore, Kona, Maui, scuba certification, other specialty certifications, NAUI, NOAA, scuba diving, scuba rental gear, sharks, SSI, TDI/SDI, Underwater Instructors, vacation, Scuba and Jason Kilgore, Naui and Jason Kilgore, How to scuba dive, skin diving, snorkel, mask, fins, Reef Relief, coral reef, reef fish, maui divers, dive shops, scuba dive shops, cave diving, ice diving, wreck diving
The Philippines is an archipelago consisting of 7,107 islands. They separate the Celebes Sea and the South China Sea from the Pacific OceanThe archipelago is the second-largest in the world after Indonesia.
The warm, clear waters of the Philippines are known to contain some of the most diverse and beautiful marine life to be found anywhere in the world. Its waters are home to more than 3000 species of fish and 448 species of coral (compared to 700 species of fish and 100 species of coral in the entire Caribbean). But there have also been a lot of mixed reports on the destructive aftermath of dynamite fishing. Many visitors return from the Phillippines dissapointed divers because they didn't encounter the abundant marine life and healthy reefs others talk so enthusiastically about. Although some of the world's most extensive coral reefs are found in the Philippines, they are under such sustained assault by dynamite fishing that marine biologists say the corals are on the verge of utter collapse.
"There are many horrific things going on in the world's oceans, but this tops the list," said John McCosker, the chairman of aquatic biology at the California Academy of Sciences in San Francisco. "When divers talked about the world's finest coral reefs 20 years ago, the consensus for the top spot was always the Philippines, but nobody feels that way now." Read more here...
A member of the Dive Global team snorkeled off Boracay island 20 years ago and remembered the reefs looking quite healthy back then. We were curious to find out from Thierry what his general impression was and if it still is a country worthwhile going to for scuba divers. Thierry visited quite a few islands during his stay and traveled by air, bus, ferry, banca (the traditional outrigger boat) and the famous Jeepny to get to the different places on his itinerary. A jeepny, for those of you that don’t know, is a US military vehicle left there in the Second World War. The jeeps have taken on a life of their own. Over the years, the Philippines have decorated these vehicles to their hearts content. You find them everywhere as a local means of transportation and they are considered a national symbol of the country.
Generally speaking, dive sites in the Philippines are known to include walls and drop-offs, coral gardens, drift dives and many rare and truly unique creatures including huge numbers of riggerfish, parrotfish, pennant fish, moray eels, surgeonfish, snappers, groupers, moorish idol, lizardfish, gobies, batfish, lionfish, trumpetfish, pufferfish, filefish, emperors, wrasses, fusiliers and trevallies. Invertebrates from the tiniest transparent shrimp and neon-colored nudibranchs to huge basket sponges adorned with hundreds of multi-colored crinoids can be found.
Anemones, sea cucumbers, starfish and worms reside with vast numbers of hard and soft corals and gorgonian sea fans. Turtles, octopus, cuttlefish, manta rays, eagle rays and sharks make guest appearances in certain areas.Palawan, which is south of Luzon, is considered the best (commercialized) diving destination in the Philippines. Shipwrecks abound in Coron, while excellent coral formations can be found in El Nido. Apo Island and the Tubbataha Reefs, to name a few, are still considered coral paradises.However, if you prefer to stay near Manila, you can go on a day trip to either Batangas (Anilao or Nasugbu) or Mindoro (Puerto Galera). Boracay is also very popular and easy to reach by a direct flight from Manila. It offers some amazing drift dives on walls and the beaches as positively stunning!
The island has become more commercialized over the years however and isn't as idyllic as it used to be.Thierry had an amazing time and even though he experienced some great dives in other locations, the highlight of his trip definitely was a visit to Malapascua Island which is known for a dive location where regular encounters with thresher sharks are pretty much guaranteed. Malapascua Island is in the Visayan Sea and belongs to Cebu. Cebu is easy to reach but this area has not yet been over-commercialized in diving terms and is considered one of the better exciting and off-the-beaten track diving destinations in the Philippines.
Keywords:
Advance Scuba training, Adventure Sports, airlines, Basic Open Water, Digital Underwater Photography, discount travel, Divemaster scuba, Enriched Air, Extreme Scuba and Jason Kilgore, family travel, family vacations, Hawaii reef divers, Hawaii Scuba Diving, Hawaiian Islands, Hawaiian Islands sight seeing, hotels, Jason Kilgore, Kona, Maui, scuba certification, other specialty certifications, NAUI, NOAA, scuba diving, scuba rental gear, sharks, SSI, TDI/SDI, Underwater Instructors, vacation, Scuba and Jason Kilgore, Naui and Jason Kilgore, How to scuba dive, skin diving, snorkel, mask, fins, Reef Relief, coral reef, reef fish, maui divers, dive shops, scuba dive shops, cave diving, ice diving, wreck diving
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