Beautiful Oceans Blog : Applied Coral Reef Biology For Snorkelers, Scuba Divers And Underwater Photographers

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Coral Reef Mapping Adventures at Club Med

Published by Bridget Spelke January 23rd, 2008 in Reef Mapping Adventures and Coral Reef Biology. 0 Comments

Hello, this is Bridget from Beautiful Oceans. As you may know, we took a “giant stride entry” into 2008 by sending two of our lucky Staff Science Instructors to Club Med’s stunning resort on Columbus Isle - San Salvador, Bahamas.

Club Med Beach - Columbus Isle, Bahamas

For the past three month, Ian and Natascia have been spending their days underwater working hard to develop 3D-maps of the most commonly visited dive sites, for use in Beautiful Ocean new Coral Reef Biology Adventures at Club Med Columbus Isle. While ‘reef mapping’ comes with its own set of trials and challenges, few of us are fortunate enough to share our daily work environment with a passing hammerhead shark or this beautiful queen triggerfish. As such, we are a starting a new mini-series, “Reef Mapping Adventures”, to share with you some of Ian and Natascia’s more remarkable sightings as they map the reefs supporting this diverse and abundant display of life. Described by Ian as some of the best diving he has experienced in the Caribbean, we give you a virtual dive, with photographs and anecdotes of species and their unique behaviors. Be warned! If these descriptions have a similar effect on you as they have had on me, you might find yourself tempted to abandon terra firma, grab fins and wetsuit, and dive right in!

Here is little sample to wet your appetite: On January 19th, Ian spent the afternoon mapping one of the resort’s many snorkeling sites, called Staghorn. In his hour-long swim, he encountered two southern stingrays, one yellow stingray, two hawksbill turtles, and a Nassau grouper sizing up a lionfish. Perhaps most remarkable, all this happened only 100m from the shore and in water less than 5m deep!

Red Lionfish

Did you know that the red lionfish is an Indo-Pacific species that started to invade Caribbean and Atlantic reefs less than 10 years ago? These gorgeous looking fish have a formidable set of defenses that Caribbean species are unable to handle. Their “lion-like” dorsal, anal and pelvic fins are each equipped with vicious stinging spines, painful to humans and poisonous to potential predators. When Ian describes the Nassau grouper checking out the lionfish, he’s observing precisely the mechanism through which this invasive species has spread: the big predator of the Caribbean can check out this funny looking fish for as long as it wants, but it won’t find a way to eat it. In contrast, the opportunistic lionfish has been devouring native fishes and crustaceans at an alarming rate: even the juvenile Nassau grouper has been found in its stomach. Quite the role reversal for the grouper! Today, the small population of lionfish first observed in 2000 has expanded to the entire East Coast of the United States, with individuals reported as far north as Massachusetts.

In addition to being an exciting year for Beautiful Oceans, 2008 marks the beginning of the second International Year of the Reef (IYOR), a worldwide campaign devoted to raising awareness of the value and threats facing coral reefs throughout the world. Similar to Beautiful Ocean’s aims, the campaign organized by the International Coral Reef Initiative (ICRI) seeks to motivate individuals to take actions to protect these precious ecosystems. To find more tips such as the one listed below visit www.iyor.org.

Tip of the Day:

Educate yourself about coral reefs and the creatures they support. How many different species live in reefs? What new medicines have been developed from reef organisms? Participate in training or educational programs that focus on reef ecology. When you further your own education, you can help others understand the fragility and value of the world’s coral reefs. (www.iyor.org)

Jet-skis make great artificial reefs

Published by Ian Popple August 5th, 2007 in Marine Conservation, Reef Ecotourism, Authors and Diving Trips. 1 Comment

Standard Podcast [7:41m]: Play Now | Play in Popup | Download

No I’m not about to highlight a neat new scientific research paper, just a little idea I had the other night about how to deal with the plague of jet-skis infecting in our planet. As you’ve probably guessed from my desire to place jet skis at the bottom of the ocean, I’m not a fan.

In many Caribbean islands – Barbados being a classic example – many local operators spend the day zipping between beaches in an attempt to rent their jet-ski out to as many tourists are possible for an average price of around $25US for 15 minutes. At the last count there were over 100 operators on the south and west coasts of Barbados. That’s nearly 7 per mile, but the concentration is usually much higher around popular beaches. Consequently, there’s pretty-much nowhere you can go on the west and south coasts of Barbados to escape the annoying mosquito like buzz of jet-skis. There are also very few locations where you actually feel safe in the water, especially as a diver or snorkeler.

Now, far be it for me to get on my moral high horse and tell people how they should and should not spend their well-earned time and money, but I figure everyone should know a few truths about jet-skis before they decide to hand over 25 bucks and waste 15 minutes of their life.

JET-STINK

Jet-skis release large quantities of hydrocarbons into the environment, polluting both our water and atmosphere. One of the main reasons for this is that most jet-skis are powered by dirty 2-stroke engines that discharge as much as one third of their fuel and oil unburned into the water and air. According to the Environmental Protection Agency, 2-stroke engines are the number one source of toxic water pollution in the US. A one hour jet-ski ride can release as much as a gallon of unburned fuel into the environment. Some estimates suggest this amount is even higher. Now, multiply that figure by the number of operators and you have some serious pollution to the environment – about 20 bathtubs full of fuel per day!

Jet ski in action Even low hydrocarbon levels in aquatic systems can have serious toxic affects on plankton, fish eggs and larvae, and crustaceans like crabs, shrimps and lobsters. Remember the environmental disaster caused when the Exxon Valdez ran aground in 1989, spilling nearly 11 million gallons of crude oil into Prince William Sound, Alaska? Well it is estimated that jet-skis alone contribute the equivalent of four Exxon Valdez spills to American waters annually. Add 2-stroke outboard engines to this and the number rises to 15 Exxon Valdez spills per year. Research from Michigan State University indicates that the toxicity of such discharges is made 50,000 times worse by the ultraviolet light of the sun, so just imagine what this is doing to our coral reefs!

MOS-SKI-TO

The mosquito-like high-pitched whine of a jet ski is not just irritating; it is dangerous to both humans and wildlife. Underwater, it is next to impossible to figure out the direction from which a jet-ski is approaching. Considering most jet-skis are capable of hitting speeds up to 60 mph, they will often on top of you before you have time to figure it out even if you could!The noise associated with jet skis is also known to disturb wildlife. Jet-skis emit 85 to 105 decibels of sound per unit. For comparison, a busy city street usually clocks in at around 70 decibels and nearby jet plane measures around 150 decibels. The United States Park Service limit on noise pollution is 82 decibels at 82 feet; jet-skis are borderline at best.

Studies by Woods Hole Oceanographic Institute describe how jet skis, which lack low frequency sounds, fail to provide enough warning of approaching danger to surfacing animals like birds, mammal and turtles. Obviously this can results in a great number of collisions with these animals. Numerous studies have also demonstrated that jet-skis disrupt the feeding and nesting of shore birds and cause other animals to change their natural behavior.

SEA-DOO?…SEA-DON’T!

In many countries, like Barbados for example, you don’t need a license or even any experience to rent a jet-ski. Can you imagine if motorbikes were rented out in a similar, irresponsible way? Many of the people that rent jet-skis have no idea how to operate one, some are not even aware that they lack breaks, and most have no idea what a dive flag looks like! It is hardly surprising therefore that jet-skis account for 50% of all boating accidents, while represent less than 10% of all motorized water craft. This is serious food for thought. And let’s not forget that the victims in these accidents are not just jet-ski operators, but also other boat operators, swimmers, snorkelers, divers and even people on shore!

For every country that brushes the jet-ski problem under the rug, however, there are others that tackle the issue right. St. Lucia is one such country, Dominica is another. Last month I spent two weeks in the beautiful and well-managed Soufriere Marine Management Area (SMMA) certifying Beautiful Oceans instructors at Sunswept Resorts (more about this in my next blog). The SMMA strictly controls the use of jet-skis, and it makes a huge difference. This is the kind of peace, tranquility and safe diving and snorkeling that you expect when you visit the Caribbean.

How to survive jet-ski infested waters

• When swimming or snorkeling always try to stay within clearly marked swimming areas

• When diving or snorkeling, always carry a dive flag, even if you are in a no-boating area. It doesn’t matter how close to the beach you feel you are (or even on it) jet-skis have been known to go there!

• If you are duck-diving while snorkeling and hear a jet-ski approaching try to surface as close to your dive flag as possible. If you cannot reach your dive flag, or you do not have one, raise your hand above your head as you surface. You may even wish to remove a fin to hold above your head as you surface. The idea is that this presents an object that hopefully will be visible before your head, allowing the jet-ski operator to adjust course and avoid a collision

How to be a responsible jet-ski operator

• Always adhere to local water craft regulations. Ensure you have all the necessary permits and never enter swimming areas

• In some countries you must have a license to ride a jet-ski. In countries where the law is more relaxed make sure you never lend your jet-ski to a minor or someone without experience

• Always respect other water users. Know which side to pass other boats and jet-skis. Learn how to recognize dive flags and stay clear of them!

• Keep your speed down. This is particularly important in crowded areas, and around divers, snorkelers and swimmers

• Ensure that your jet-ski has a regular service. This can help minimize pollution to the natural environment

• Newer jet-ski models are a massive improvement on old models. Some new models use cleaner 4-stroke engines and/or catalytic converters, which help reduce emissions

You Scratch My Back… A Tale of Cleaning and Pseudocleaning

Published by Natascia Tamburello July 6th, 2007 in Coral Reef Organism Behavior, Underwater photography, Reef Ecotourism, Coral Reef Biology, Authors and Eco-Diving. 1 Comment

You Scratch My Back... A Tale of Cleaning and Pseudocleaning [5:09m]: Play Now | Play in Popup | Download

Hi again everybody, this is Natascia from Beautiful Oceans, and if you are listening to this entry as a podcast you can find us and our blogs at www.beautifuloceans.com.

Today I’d like to talk to you about some alternative feeding strategies of organisms on the reef and the interesting behavioural relationships these strategies create – in particular, I will be discussing the sordid triangle between reef fish, their parasites, and the cleaner organisms who love them.

Just as is true here on land, not everybody on the reef makes an honest living by actively hunting or foraging for food, and some organisms such as the many parasites that take reef fish as their hosts have chosen the carefree lives of freeloaders. Of these the external parasites, also known as ectoparasites, will be the most apparent to divers; sometimes dramatically so!

Blackbar Soldierfish with attached Chymothoid isopod. While most ectoparasites, including copepods and flatworms, are too small to see, Chymothoid isopods are conspicuously large parasitic crustaceans resembling pillbugs that attach to particular reef fish hosts as larvae and remain there for the rest of their lives. By attaching near the head of a host, the isopods are privilege to the food scraps missed by feeding hosts, and the hosts, in turn, do not seem to be disturbed by their hitchhikers. In contrast, many other ectoparasites take up residence at the host’s expense, often burrowing into the delicate tissue around the eyes, fins and mouth, and sometimes even penetrating the gills. Once embedded, these parasites feed on host blood or tissue, and can often lead to illness and reduced reproductive potential. It is therefore in the interest of the fish to get rid of these parasites regularly before enough accumulate to kill the individual.

Many fish attempt to scrape the parasites off themselves by rapidly diving towards the bottom and rubbing up against sand or rocks in a behaviour known as ‘flashing’, however, this is both ineffective and energetically expensive, and it remains a last resort when no alternatives are available. Instead, fish attempt to benefit from visits to sites known as ‘cleaning stations’ whenever possible. At these stations, small fish and shrimp collect to feed on, and thus remove, the parasites found on client fish and they occasionally nip at the scales or mucous coating of the clients themselves. When visiting these stations, client fish typically tilt their bodies upwards, open their mouths and flare out their fins so that cleaners can get into every nook and cranny. Some fish even assume a particular colour pattern to advertise their desire to be cleaned.

Although it was once assumed that what kept clients coming back to cleaning stations was the promise of relief from parasites, it appears that the behavioural relationship is less straightforward than that! As early as the 70’s, scientists have often captured and examined client fish just arriving at cleaning sites and found them to be parasite-free, and in recent years this has led to the proposal that the client fish might just keep coming back for a cleaning because, well, it’s nice to be pampered every once in a while isn’t it? To put it in more scientific terms, the fish are thought to return for the promise of tactile stimulation, regardless of their parasite load, in much the same way that humans love a good massage any time and not just when we have tense or knotted muscles! From the point of view of the cleaner organisms, providing pleasant sensations during cleaning services would be advantageous as it would encourage repeat customers and thus a steady meal ticket. Redband parrotfish that appears to be engaged in psuedocleaning. Support for the tactile stimulation argument came in 1977 when Ronald Thresher, then at the University of Miami, first described scientifically a bizarre behaviour known as pseudocleaning. Off the coast of Florida, Thresher observed several species of parrotfish as well as doctorfish posing, as if to be cleaned, in or near the fronds of gorgonians and other soft corals which contained no cleaning species upon later inspection. During these posing sessions, which lasted up to 18 minutes, the fish appeared to be in a trance as is the case for fish posing at real cleaning stations, and on subsequent sessions fish always returned to the same gorgonian bush. This site fidelity supports the theory that fish return to sites of tactile stimulation due to positive reinforcement, which would be provided just as well by the softly waving gorgonian fronds as it would by the attention of cleaner species. This does not mean that cleaning stations are not useful, as cleaners still do remove parasites that could make fish sick, and reefs with an abundance of cleaning stations generally have more and healthier fish. All it means is that fish may have ulterior motives for visiting cleaning stations when they do!

Next time you’re on the reef diving, snorkeling or taking photographs (underwater photography that is), look for cleaning and pseudocleaning behaviour, and remember that just like yourself, reef fish can also appreciate a nice massage! Join me again next time for more interesting insights on reef organism behaviour and ecology.

“Keep off my lawn!” - The Dilemma of the Dusky Damselfish

Published by Natascia Tamburello June 13th, 2007 in Reef Ecotourism, Coral Reef Biology, Authors and Eco-Diving. 0 Comments

“Keep off my lawn!” – The dilemma of the Dusky Damselfish [4:26m]: Play Now | Play in Popup | Download

Hi everyone, this is Natascia from Beautiful Oceans; if you are listening to this entry as a podcast you can find us and our blogs at www.beautifuloceans.com.

As many of you may already know, damselfish are highly territorial fish that fight tooth and fin to defend both food resources and nesting grounds within the bounds of their chosen swath of reef. Stephan has already described how all this hard work translates into reproductive success in the blog entry “Damselfish - The King Of Coral Reef Dating”. Here, I would like to focus in on one damselfish species in particular, the Dusky Damselfish (Stegastes fuscus), in order to shed more light on the defensive strategy of these feisty little fish.

Dusky damselfish vigorously defend their territories against eachother, other herbivores, and known egg-snatchers. To get their point across, Dusky damyellowtail.selfish use a varied repertoire of aggressive signals. Like most other fish, they respond to a threat by first flaring out all their fins to appear bigger and more imposing than they really are in a world where size matters. If this impressive display is not enough to repulse intruders, Duskys will proceed to vigorously chase and even nip strategically at the vulnerable fins and eyes of their opponents. In the face of such an onslaught by a much faster and more nimble opponent, even larger fish choose to move away despite their size advantage.

Many of you may not know it, but these damselfish also use sound signals to intimidate trespassers in much the way a barking dog advertises his dislike of the postman’s intrusion. In the Dusky damselfish, these popping and thumping noises are produced by vibrating small muscles attached to the swim bladder and thereby using it as a sounding board to amplify and project the sound, the way the sound of a guitar’s vibrating strings is amplified by the large, hollow guitar body. Because the sounds produced by most fish lie in the low frequency range not normally detectable by the human ear, they are seldom heard by divers underwater. However, these sounds can be recorded using hydrophones, microphones designed for underwater use, and by artificially increasing their frequency they can be made audible to humans. Click on the above image to hear an angry Dusky damselfish sound off!

Although the Dusky damselfish puts up a valiant defence against intruders, there are a few species that routinely escape the brunt of its wrath. Eco-divers and eco-snorkelers may often see the larger Yellowtail damselfish (Microspathodon chrysurus) ranging across Dusky damselfish territories and helping themselves to a veritable algal salad-bar. Yellowtail damselfish, one of the biggest members of the damselfish family, will establish a territory which overlaps many smaller territories belonging to Dusky damselfish. At least four Dusky territories can be seen within the larger territory of the Yellowtail in the adjacent photo, taken off the West coast of Barbados, but according to one study as many as eleven Dusky damselfish territories may be included in that of a Yellowtail. Yellowtails use their large size to dominate the smaller Duskys and spend their days leisurely grazing among the many algal gardens tended and defended largely by their hapless hosts. Because of this relationship, divers will rarely ever see Yellowtails chasing intruders, a job which they leave mostly to the Dusky damselfish they govern. Because the Yellowtails spread their grazing out over many Dusky territories, each individual Dusky damselfish is minimally affected and so pragmatically tolerates the presence of this bully rather than wasting valuable energy trying to chase the dominant fish away.

Instead, the Dusky damselfish chooses to focus on repelling external intruders such as the voracious Blue Tang (Acanthurus coeruleus) which pose a much larger threat to its personal algal garden.

I hope you have enjoyed this entry and hopefully learned a little bit more about the fascinating behaviour of the Dusky damselfish. Join us again for more fascinating tales of marine organism behavior and ecology!

Giant barrel sponges (and lots of little stuff) abound in Dominica

Published by Ian Popple May 2nd, 2007 in Reef Ecotourism, Coral Reef Biology, Authors and Diving Trips. 0 Comments

Dominica giant barrel sponge [4:09m]: Play Now | Play in Popup | Download

Hi everyone

I’m writing this blog from Dominica, where I’ve come to check out the diving and to assess the island for inclusion in our list of eco-dive adventure destinations for next year.

The island of Dominica is simply beautiful. There are 365 rivers (one for ever day of the year) on the island that flow through thick, pristine rainforest. The island is mountainous and has some of the most stunning vistas in the Caribbean. The reefs are also pristine. This morning I did two reef dives in the south of the island – the Soufriere pinnacles. Both dives were wall dives, with a great diversity of corals and sponges. One of the most common species I saw was the giant barrel sponge (Xestospongia muta), often called the “redwood of the deep” because of its large size and longevity – they can grow to the size of a compact car and live for over 100 years. Scientists have documented giant barrel sponges increasing their size by around one third in as little as 18 months – a staggering increase in growth – although these growth rates seem to be seasonal or at least sporadic.

giant barrel sponge Not many people realize that sponges are actually capable of photosynthesizing in much the same way as corals, as well as filter feeding (removing tiny planktonic organisms from the water). Sponges however do not possess symbiotic zooxanthellae – the microscopic algae that live in the tissue of corals. Instead they have a symbiotic cyanobacteria that photosynthesizes. These cyanobacteria also give the sponge its grey to reddish/brown colouration. Like corals sponges can become bleached, which involves the loss of their symbiotic cyanobacteria. Sponge bleaching was first reported about 20 years ago. They change colour to a pale white, sometimes reduce in size and become more susceptible to predation by creatures like parrotfishes. This kind of bleaching is very common, but rarely fatal to the sponge.

One of the largest threats to giant barrel sponges appears to be monofilament fishing line. According to a 2002 study in the Florida Keys, monofilament line made up 38% of the total debris found on the reef. Monofilament line can easily cut through giant barrel sponge, and it is not uncommon to see sponges sliced in two. Although the sponge may be able to recover from this (depending on the extent of the damage), the removed pieces of sponge go not reattach and regrow.

feather duster worm inside barrel sponge The giant barrel sponge is covered in Beautiful Oceans’ second course Coral Reef Ecosystem & Foodweb, and the island of Dominica is currently on the drawing board as a new destination for our eco-adventure trips in conjunction with AquaDreams. But don’t worry, if you can’t wait ‘til next year, sign up for one of our upcoming trips this fall/winter. Giant barrel sponges can be found in all of the islands we will be visiting and your marine Biology Instructor will be able to tell you all about them.

Upcoming Beautiful Oceans eco-dive trips include:
Utila (August 18-25)
Grand Cayman (September 1-8)
Grenada (October 13-20)
Bonaire (December 1-8)
Curaçao (January 13-20).

To learn more about Beautiful Oceans’ eco-dive trips click here.

Until next time…happy diving,

Ian

Great White Sharks, Ultimate Top-Predators

Published by Stephan Becker March 8th, 2007 in Reef Ecotourism, Coral Reef Biology, Authors and Diving Trips. 0 Comments

Beautiful Oceans, Great White Sharks, Top Predators [10:16m]: Play Now | Play in Popup | Download

Great White Sharks - The Ultimate Top-Predator?

Summary: Great whites possess evolutionary adaptations that set them apart form any other top-predator, even other sharks. These adaptations include: highly developed electrosensory organs, hydrodynamic body shape with high maneuverability, strength, high ratio of red muscles, efficient combination of paired and unpaired fins, intricate network of dermal collagen, skin made of dermal denticles and much more…

Hi there, this is Stephan from Beautiful Oceans. You can find our blogs and podcasts at www.beautifuloceans.com.

Today, I would like to initiate a series of blogs and podcasts discussing why the great white shark can without the slightest doubt be considered the ultimate top predator of our Oceans. We all hear from time to time about these fearsome beasts – but instead of adding to gruesome accounts what I would like to do is to analyze in detail what makes Great Whites superior to any other fish species out there in the sea – well actually superior compared to its own kind – Great Whites can truly be considered the ultimate top predator of our Oceans - now lets have a look why.

The term top predator generally refers to the position a species occupies in the food chain — or better — food web of an ecosystem. As you may know, ecosystems can be as small as a drop of water or as big as planet Earth. Therefore, the position a species occupies in the food web also takes into consideration the geographical range in which a top predator operates. Although sharks are generally referred to as top predators, not all sharks are predators in the first place. The majority of the 370 shark species are harmless and some are not at all interested in hunting for large meals of meat but almost exclusively feed on plankton, macro-algae or smaller crustaceans or a combination of the three. The gigantic whale shark for example, incidentally the biggest fish in the world reaching a length of up to 46 feet (14 m) and weighing up to 15 tons, is a filter feeder – filtering microscopic planktonic organisms out of the sea – quite remote from a fearsome top predator you may say. By the way, did you know that whale sharks may live up to between 100 to 150 years?

The great white shark, bearing the scientific name of Carcharodon carcharias is the world’s largest predatory fish, reaching 21 feet (7 meters) in length and weighing up to 4,800 pounds (2,100 kilograms). It comes with numerous evolutionary advantages that are both surprising and fascinating. Lets have a look at two of them to begin with: movement and electrosensory reception.

Movement:
In 2002, a scientific research team tagged several white sharks with what was brand new technology at that time: electronic satellite tags capable of tracing long-distance migrations of large pelagic species over several weeks or even months. Before 2002 it was widely believed that white sharks spent most of their lives relatively close to shore. But scientists were in for a surprise; they discovered that white sharks can range across vast stretches of the open ocean. In fact, one male tagged along the Central California coast migrated thousands of miles to the warm waters off Hawaii — and remained there for nearly four months!

Now, how may the greater range of white sharks contribute to their position at the top of the food chain? Well, if Great Whites are capable of traveling longer distances wouldn’t it make sense that it is not as dependent on a local ecosystems compared to other species that lack the ability to migrate, such as a resident top predator like the white tip reef shark, lemon shark or even some hammerhead species that stick more closely to local reefs. What this means is that great white sharks, because they are less sedentary, also have a higher probability to find prey in a wider area and hence are at home in a wider ecological niche.

For more information on the study conducted by a team of 6 Scientist working out of California, click here:
http://news-service.stanford.edu/news/2002/january9/sharks-19.html

Electrosensory reception:
We all know that sharks have senses that surpass ours by far. One of them is electrosensory reception — sharks can detect electromagnetic fields in the water, enabling them to locate their prey on a distance of few meters even at night or when their prey tries to hide in the sand – a bad place to hide from a shark! But how does this ‘electrosensory reception’ work you may ask?

Actually, the shark’s body acts as a dipole — one positive end, one negative end –and thus produces an electric field. Electric fields are perceived by fragile, jelly-filled electroreceptors called ‘ampullae of Lorenzini’ covering the entire surface of the shark. When an alien field approaches within a few meters of the shark, it interferes with the sharks electromagnetic field and allows it to sense things it might not see, hear or smell. This ability to sense weak electrical fields — as low as 0.005 microvolts per centimeter — also allows sharks to navigate with the earth’s magnetic field, like dolphins or whales for example.

For more information about electrosensory capacities in sharks, click here:
http://hoopermuseum.earthsci.carleton.ca/sharks/P4-1.htm

Now, as we approach the end of this podcast: Have you ever dreamed about possessing a key that would unlock the mysteries of the coral reef? A key helping you find the most interesting creatures on the reef, helping you understand what creatures do on the reef and which creatures eat what on the reef? With Beautiful Oceans this dream now has become reality! We offer exciting coral reef ecotourism adventure trips for scuba divers to selected destinations in the Caribbean! Each trip is accompanied by one of our trained Science Instructors who will help you unlock the mysteries of coral reef organisms, their behavior and the ecosystem in which they live. Two coral reef biology courses, in-water discovery dives and specially designed underwater dive slates — your keys to the underwater world – complete the experience. Log on to www.beautifuloceans.com to learn more about the scheduled trips and reserve your spot!

Wish you a great day and meet you soon for our next podcast – Bye-bye…

“Out of sight, out of mind?” – Deep Sea Trawling

Published by Laura Tabet February 26th, 2007 in Marine Conservation, Authors and Corporate Social and Environmental Responsibility. 0 Comments

Beautiful_Oceans_DeepSeaTrawling_Shark [3:30m]: Play Now | Play in Popup | Download

Hi there, this is Laura from Beautiful Oceans, you can find our blogs and our podcasts at www.beautifuloceans.com. Today, I would like to talk about the video of the prehistoric shark filmed in Japan January 21st 2007.

This rare sighting of a living frilled shark in such shallow waters was firstly reported to marine park scientists by a fisherman. The incredible video of the prehistoric shark was definitely very popular on most news sources, astonishing viewers about the mystery of our deep seas. Did you know that more is known about the moon’s surface than of our planet’s sea floor? So much is still unidentified to science at such great depths. For example, frilled sharks -Chlamydoselachus anguineus- habitat ranges from 200 to 1000 meters. Along the same line, last March 2006 a great marine discovery of a new Smoothhound shark species Mustelus hacat was initially reported by fishermen off the coast of Mexico. This shark also lives at deeps greater than 200 meters.

The capture of the deep sea creatures by fishermen is often the result of by-catch in bottom trawling. By-catch refers to all organisms which are non-selectively caught by fishing boats harvesting a specific species. Deep sea trawling consists of the deployment of large nets which drag at the bottom of the sea floor weighed down by steel weights and rollers weighing several tons. This process is extremely destructive: firstly the trawling nets remove any species within their path. Non-targeted species are discarded as by-catch, and most likely will not survive. An article in National Geographic states that “In 2000 up to one million tons of unwanted sea life was discarded from nets in the U.S. alone”. Secondly, trawling machinery smashes all life on the sea bed: this includes the destruction of corals, the turning up of sediments and its consequent disturbance of all marine life. It is also believed that the extent of deep sea floor destruction is more extensive that the damage done to forests: worldwide trawling activities occur in an area 150 times greater than yearly clear-cut forest areas.

The consequences of these fisheries are disastrous. Furthermore, it is only recently that scientists are discovering and mapping cold water coral reefs found at depths of 1000 to 2000 meters located on seamounds. Many organisms found at theses depth date back to prehistoric times. Theses deep water corals have the characteristic of being extremely slow growing animals, some aged over 1 000 years and are consequently extremely slow to recover from any outer stresses. Most importantly, theses reefs play a vital role in the oceans ecosystems: theses underwater seamounds attract planktonic organisms which form the base of marine food webs. Scientists have defined theses areas of important biological significance. That’s why, high densities of fish are attracted to theses deep sea reefs making them a major target to trawling fisheries (click here for video).

As far as fishermen are concerned, deep sea trawling practices are quite unregulated, and in my view, shockingly still represent a legal way of fishing. Environmentalists and conservationists are still pushing for the protection of the deep seas such as the adoption of a moratorium of trawling, but hardly any nations have responded to this plea. When watching the video of the frilled shark, I could not help but wonder about all the other shark species which are critically endangered by human theses large scale fisheries.

According to the World Wildlife Fund, every two minutes, a shark a dolphin or a turtles dies as a victim of by-catch. The destruction of deep sea habitats combined with overfishing practices will not allow the ecosystem to recover. And if we ever reach that point in time, it will be too late to save our ocean fisheries and cold water reefs. Ironically, it is only when there will be no more fish to eat that people will realize that the oceans services should not be taken for granted. I feel that as long as theses activities are not affecting are daily life, it is easy to ignore them….

I would like to hear your thoughts about this. Do you think consumers are even aware of theses issues? And how to you think we can increase awareness about the value of our deep seas?

I hope you enjoyed this blog & podcast. To learn more about our coral reef biology courses and coral reef biology dive trips to the Caribbean, please visit www.beautifuloceans.com. Until next time – bye-bye…:-)

Diver impacts on the reef

Published by Laura Tabet February 19th, 2007 in Reef Ecotourism, Authors and Eco-Diving. 0 Comments

BeautifulOceans-DiverImpactsOnTheReef-GeneralIdeasAndTips [4:17m]: Play Now | Play in Popup | Download

Hi there! This is Laura from Beautiful Oceans! You can find our blogs and our podcasts at http://www.beautifuloceans.com. Today I would like to bring up the subject of scuba diver behavior and its potential impacts on the reef.

Beautiful Oceans actively promotes the practice of eco-diving for the protection of coral reefs and encourages divers to increase their awareness of the fragile coral reef ecosystem. However, before I get started on the importance of adopting eco-practices some may ask “how do divers affect the reef?” Many human activities affect the world’s coral reefs, such as pollution from solid waste, sediments, chemicals and sewage, all of which lower coral survival rates. Unsustainable coastal tourism developments also gravely affect marine life. Reef tourism as well as scuba diving are booming industries, attracting millions of people each year to enjoy the underwater world. Scuba diving is sometimes considered an ideal way of using the reef to economic advantage, while avoiding negatively impacting the reef. However, although diving may be considered a ‘no-contact’ activity in regards to the reef, this is not the current scenario. Due to their close proximity to the reef, divers can pose a real threat to surrounding organisms. In this way, with the growing popularity of diving it is not uncommon to see dead and broken corals in intensively used areas. This leads to the visual degradation of scuba diving sites and contributes to the destruction of the reef.

Diving impacts can be categorized as intentional and unintentional. Intentional contact is generally propagated through ignorance, with divers being unaware of the negative effects that contact can have on reefs. Although the effect of touching the reef by one diver can seem minimal, when multiplied by all divers, even careful contact can be very harmful to the reef (for more click here). This contact includes the purposeful touching or harvesting of marine resources, as well as the harassment of marine animals. Divers may also purposely rest on, stand on, hold on to, or otherwise touch the reef itself. It is important to remember to maintain neutral buoyancy and be aware of currents in order to avoid this contact with the reef.

Unintentional contact with the reef is also of concern. Swimming too close to the corals and brushing them with both body and equipment can cause coral breakages. Most unintentional contact with the reef occurs through fin-kicks, which can both break corals and sponges, as well as re-suspend sediments, which stress corals and marine organisms. Unintentional contact generally occurs through lack of attention, poor swimming and or buoyancy techniques and or incorrect weighting.

It is also important for divers to be aware of more vulnerable areas of the reef. Generally, any area with high levels of coral cover, particularly branching corals, are vulnerable. Variations in reef structures and area characteristics (such as reef slopes and strong currents) also create dive sites more susceptible to damage. Marine photography is another factor that can amplify diver destructive behaviour, whereby focus on “getting the perfect shot” diverts diver attention from staying off the reef. With the widespread availability of cheaper underwater cameras, it is important that photographers be extra cautious while taking pictures particularly while operating near more vulnerable areas of the reef (for more click here).So what is the take home message? Don’t be discouraged! Diver impacts may not be the most important threat to coral reefs, but due to divers close proximity to the reef extra care must be taken when diving. Scuba divers can act as ambassadors of coral reef protection, and can actively promote eco-practices when amongst other divers.

For example, make sure that equipment is well secured to avoid it brushing over the reef and possible breaking coral. It is also recommended to keep a safe distance from the reef, especially for novice divers still ameliorating their buoyancy skills (for more best practices click here)

Environmentally conscious diving is something that any diver or dive shop can do, and even on an individual basis, this can contribute immensely to the well being of reefs. On a global scale, such initiatives can ensure that the needs of the diving industry and coral reefs are fully compatible. Scuba diving and coral reef protection should go hand-in-hand if we are to preserve coral reefs for future generations. Eco-diving can limit diver impact on reefs, while contributing to coral reef education and awareness, helping to maintain and preserve a healthy reef eco-system, and keeping it beautiful for diving.

I hope you enjoyed this blog & podcast. To learn more about our coral reef biology courses and coral reef biology dive trips to the Caribbean, please visit http://www.beautifuloceans.com/. Until next time – bye-bye…:-)

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