"Teaching people about the world in which we live."

TerraX.org , Coral Sea, Great Barrier Reef (18:01, May 5):
This evening we will begin our week long adventure aboard the Undersea Explorer, a research vessel operating on the Great Barrier Reef. During the week we will live aboard this ship, steaming north and then west during the nights and diving among the coral reefs during the days. Onboard we will have a marine biologist named Emma Hutchison. Each day we can complete four dives (including one night dive) and will hear a lecture from Emma about the Great Barrier Reef. It promises to be an interesting and informative week, as well as lots of fun for our divers.

TerraX.org , Coral Sea, Great Barrier Reef (18:03, May 5):
Each evening we will write a log describing our adventures that day and telling you what we have learned and observed. The band width from the ship is limited but we will be sending some pictures to illustrate our log text. Please be sure to tune in to our interactive chat with Andy Dunstan, the research co-ordinator and operations manager for Undersea Explorer. Andy is also a marine biologist who will answer your questions about the Great Barrier Reef. The chat is scheduled for the morning of May 9 (Australian time), but May 8 for the United States and Canada. The time of the chat will be set later this week.

Michelle/Kevin, On the 'Net (17:51, May 5):
glad to hear that you made it out of port safely--your images are poetic...hope all has been peaceful and exciting. How far out will you be travelling before you begin to dive? It seems that our communications may be delayed-- and we don't want to miss any of your underwater adventure! {{{{YOU}}}}

TerraX.org , Coral Sea, Great Barrier Reef (18:03, May 5):
May 2, 1998: We stowed our gear onboard the Undersea Explorer this afternoon. The ship is berthed in Port Douglas, a short drive north of Cairns, Queensland. After our last meal ashore for a week, we boarded the ship and steamed out of the harbor at 8:00 pm. The first thing that we noticed was that we seemed to be going in the wrong direction. The red lights were on our right hand side (starboard), which is the wrong side for a ship moving out of a harbor! We were mistaken. The slogan "RED RIGHT RETURNING" is true only in the United States and Canada. Other places use a red light or buoy to mark the left side of the channel for a returning vessel, making it our right side as we steamed out of Port Douglas. It was good to know that Captain John McGregor had that correct! So we learned something: In Australia you drive on the left hand side of the road AND the channel lights are reversed.

TerraX.org , Coral Sea, Great Barrier Reef (18:04, May 5):
May 2, 1998: The rest of the evening is totally uninteresting because we went to our air-conditioned cabins and fell into our bunks very shortly after leaving the harbor. Sleeping all night to the gentle rocking of the waves in air-conditioned comfort steaming beside and actually through the Great Barrier Reef is very close to heaven.

TerraX.org , Coral Sea, Great Barrier Reef (18:05, May 5):
We awoke fairly early because our first dive was scheduled for 8:00 am. The idea of hopping into the ocean at that hour of the morning may not seem very appealing, but when the day dawns sunny and the water is 28 degrees (Centigrade), it is actually a delight. At 82 degrees Fahrenheit the sea was as inviting as a warm bathtub and much more interesting.

TerraX.org , Coral Sea, Great Barrier Reef (18:20, May 5):
May 3, 1998: Our first dive site was Harrier Reef. This is a patch reef amongst the ribbon reefs which fringe the Australian continental shelf. The Great Barrier Reef actually consists of three types of reefs. Ribbon reefs, patch reefs, and fringing reefs. I'll describe each type when I talk about diving on them. Patch reefs form when the coral can get a solid foothold (for example, on a rocky area) close enough to the surface to have sunlight. These reefs are small, almost round, and have no central island of rock. Several path reefs may occur close to one another. Harrier reef is a patch reef. This was the day's first dive and the deepest; however, most of us dove to only 25m (about 80 ft). This is about the limit of the coral in these waters, so we got to see everything. And everything was quite a lot because so many species of plants and animals are fighting for space in these sunny, warm waters. The sun is a critical element here because the hard coral which is the building block of the reef actually consists of a hard shelled animal related to the jelly fish plus a photosynthesizing one celled plant. The coral gets most of its food directly from the plants. This symbiotic relationship gives the plant a safe place to live and provides the animal with the necessary food. In addition to the coral, we saw colorful tropical fish and a very interesting one celled plant called a sailor's eyeball. The one we saw was attached to the sand and was about 2 cm (1 in) in diameter. This is very large for a single celled plant. It looks like a clear or silvery ball full of liquid.

TerraX.org , Coral Sea, Great Barrier Reef (18:20, May 5):
Our second dive was at Pixie, which is a coral formation so small that it is not even a patch reef. It is called a "bommie" in Australia. It looks like a column of coral rising from the ocean floor to within a few meters of the surface. At Pixie we got to see a mini-drama played out when a crinoid ( an animal related to the starfish) seemly attacked a diver. Now this is a silly interpretation since the crinoid was only about a foot in diameter and has very limited movement capability. However, this crinoid loosed its hold on the bommie (probably attached to a whip coral) and fell gracefully down, down, and down until it landed squarely on a diver below. The well-aimed crinoid landed on the diver's regulator hose, surprisingly close to a whip coral in shape and color and clung briefly. The diver did not like being mistaken for a resting place and quickly sent the little fellow sailing on down to a landing place on the bommie itself.

TerraX.org , Coral Sea, Great Barrier Reef (18:21, May 5):
Our third and fourth dives were at the Cod Hole. This is famous dive site because of all the large fish which live here. The cod are amazingly huge. They will swim right up to the divers because many of the tour boats allow the divers to feed them. We did not feed the cod, but we got to benefit from the very tame fish produced by this practice. When the cod swam up to me, I was amazed at its size; however, when I turned and saw a second cod swim by another diver, the effect was even more staggering. The fish was almost as long as the person and much fatter! In addition to seeing the cod, we saw a small lion fish. They are poisonous to touch, but very beautiful to look at. This fish was gorgeous because of its fancy fringed fins, although its color was uniform, almost black. During the third dive, we got pictures of a green sea turtle. The turtle is not green, but its fat is. Hence the name.

TerraX.org , Coral Sea, Great Barrier Reef (18:21, May 5):
The fourth dive was a night dive. On this dive, we knew we would see the coral feeding. They feed by extending polyps from the surface of each coral plant. The corals then look like they are covered with a soft fur. Instead we got a treat! A full grown female white tip reef shark (1.8 meters or 5 1/2 ft) swam by. She was not at all interested in us, but we found swimming with this large carnivore at night to be exhilarating to say the least!

TerraX.org , Coral Sea, Great Barrier Reef (18:22, May 5):
Ribbon reefs form a line among the northern part of the Great Barrier Reef, marking the edge of the continental shelf. During the ice age, when the oceans' water level was considerably lower, the edge of the continental shelf provided a good place for coral to get a start. This area is now under deeper water, but the reefs which began then continued to grow toward the sunlight and now form the ribbon reefs of this area.

TerraX.org , Coral Sea, Great Barrier Reef (18:22, May 5):
May 4, 1998: Last night we steamed east out of the Great Barrier Reef (GBR) and into the Coral Sea. We reached Osprey Island, a sea mount. The wall at the entrance to the lagoon falls 1000 meters (3000 ft) into crystal clear water. On our first dive at The Entrance, we saw a large shark (a black vee) and a barracuda. Schools of mackerel like fish and clusters of bright butterfly fish decorated the vertical wall on which soft corals grow. The waters here are much clearer than those on the GBR because we are further from the sand and sediment along the Queensland coast. We will dive, at different sites, on Osprey all day.

TerraX.org , Coral Sea, Great Barrier Reef (18:22, May 5):
Coral reefs are a complete ecosystem consisting of a surprisingly large percentage of animals. This is unusual because in a food chain, more plants than animals are needed. This paradox was solved when we learned that the hard reef building coral themselves are actually a symbiotic combination of a one celled photosynthesizing plant and a hard shelled animal. Marine biologists are currently studying a phenomenon called coral bleaching which occurs when the coral animal is stressed and it ejects the plant. The coral then dies, apparently of starvation. It is not yet known why the stressed coral ejects its primary food source. Global occurrences of coral bleaching have been found this year, leading to speculations about El Nino vs. Global Warming as the cause.

TerraX.org , Coral Sea, Great Barrier Reef (18:22, May 5):
Dives Two and Three should be discussed as a pair. We moved to the north end of Osprey to North Horn.

TerraX.org , Coral Sea, Great Barrier Reef (18:23, May 5):
This is the area where black vee whalers, white tips, and silver tip sharks collect. The research crew tags these sharks and tracks their movements. They hope to learn whether these sharks are an isolated population. If so, then they will study the effects of inbreeding on the population. This dive is also a wall dive. The wall drops to 1800 meters, but the action we wanted with the sharks was at about 30 meters. During Dive Two, the tourist divers got used to the idea of swimming with sharks. We saw both white tips and black vees, about 4 feet long. They swam just off the wall and showed no interest in us. It is surprising how quickly the adrenaline rush subsides. By the fourth or fifth shark, we were looking, seeing, and saying, "Oh, yes, a shark."

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
The Capture: During Dive Three, the researchers planned to capture a shark and tag it with a tracing device. They know the sharks by name and the goal was to tag Half Moon because this shark had been tagged before and still had the "surgically implanted mini-harness" in her dorsal fin although the tracer (called a "pinger" for the noise its makes on the data collector) itself had fallen off. Therefore, retagging would be just a matter of attaching a new pinger.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
All the tourist divers swam away from the ship along the coral wall and then the research divers followed with the bait box. The sharks soon followed the bait box with considerable interest. Our TerraX.org dive team was trailing with the video camera. Now we were between the bait and the approaching sharks. One of these sharks objected to our presence-I believe she thought that we would challenge her for a share of the very smelly fish bait. A shark shows its aggression by arching its back and lowering its pectoral fins as it swims toward you. This is a very frightening sight and worked quite well to back us against the reef wall. When we were properly submissive, the shark swam away after the bait box. The bait box was set on a bommie (a pillar of coral) in about 14 meters (45 ft) of water. This gave the sharks easy access to the box and the research divers easy access to the sharks. John, our dive master, held a rope loop and the chase began. As many as 8 to 10 white tipped reef sharks nosed at the bait. Add to this a mix of two large cod (about 4 to 5 ft long) and a slurry of small, colorful reef fish and the result was visual chaos! About 25 minutes into the dive, John made his capture. He slipped the rope loop over his arm and then actually grabbed the shark's tail, dropping the loop into place and pulling it taut. Since a white tip is one of the few sharks that can bite its own tail (and anything hanging onto it), this was a risky capture, but all ended well. The captive shark was a young male white tip which is a rarity at North Horn. He had been tagged before and did not need a pinger. The researchers checked the tag number to confirm his identity and the sighting. The shark was then freed and swam away.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
During the remainder of the dive, the sharks were more stirred up than they had been earlier and as a consequence, so were we tourist divers. On the whole, we agree now with the experts that shark attacks are quite rare and that this beautiful, streamlined animal is a wonder to behold.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
This evening we set out a nautilus trap. The chambered nautilus is a shell fish with a spiral shell. We have an article about the chambered nautilus on the web site. To capture a nautilus, you have to set a trap at about 200 meters (600 ft). The trap looks a lot like a lobster trap. It is a barrel shaped trap made entirely of fencing wire. Inside the barrel, chicken and fish are placed as bait. A nautilus swims in through a tunnel and drops in with the bait. It then can't find the opening to the tunnel to get out. So the nautilus sits inside and eats until dawn, when we will pull him into the boat and learn about this amazing creature.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
May 5, 1998: This was our second day diving at Osprey. Before the first dive, Emma went to retrieve the nautilus trap. The nautilus live at depths between 200 m (660 ft) and 500 m (1650 ft). They come to the "shallow" end of their range only during the night. Therefore, we set out our trap in the evening, letting out 200 m. of rope attached to a basket baited with chicken-apparently a nautilus delicacy because we trapped 18 last night! This is almost as many as they have trapped during the entire preceding eight months of the study. The total count is now 40. A nautilus is a cephalopod mollusk. A mollusk is a shelled animal. A cephalopod is a specially evolved form in which there is no separate foot (pod) remaining-as the pod that common garden snails have. Instead the pod has evolved into tentacles which now surround the mouth part (a beak). This is the business end of a nautilus; the parts which extend out from the beautifully curved spiral shell.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
Today the first two dives were at North Horn. The TerraX.org team dived the first dive and then rested during the second dive. Swimming for an hour a dive in warm ocean water should not be a particular drain on our energy, but a pharmacist onboard has suggested that the residual nitrogen that we build up during dives may be a stressor which makes us tired. The third dive was back at Admiralty Anchor to do a daytime dive in a cave.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
This evening's biology talk was about the various types of fish in the area. There are 20,000 species of bony fish in the world. We learned that fish have a bony vertebrae, an air bladder for buoyancy, and an operculum covering their gills. In these ways, they differ from sharks which have cartilage instead of bones, an oily liver for flotation, and exposed gill slits. Amongst the interesting stories was the description of the sex life of the parrot fish. Parrot fish are born female or male; both sexes are colored some shade of beige. However, sometimes as the female matures it may "decide" to become a male and continue maturing into a beautiful, brightly colored male adult. This newly made male with his bright colors is very attractive to the females. However, he has small testes and produces little sperm. Parrot fish fertilize their eggs externally, a male and female swim together, releasing sperm and eggs respectively into the ocean as a small cloud of fertility. The beige males, who have large testes and lots of sperm, then opportunistically swim into the cloud and release their sperm. They have the better chance of fertilizing the eggs because of their greater number of sperm.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
Our final dive was a night dive to release the 18 nautilus. During the day, they had been kept in cold sea water which Emma aerated occasionally with an oxygen bottle. Each nautilus was measured and labeled with a number. (So far one nautilus has been recaptured in the eight months of the study.) Before the release, all the tourist divers got into the water and descended to 15 m (45 ft). Then Emma dove and brought down the nautilus in a pillow case. She released them one at a time. Sarah, Emma's helper for this dive turned each one a bit to help release any excess nitrogen in its shell (remember this is the nautilus's flotation device). She called this burping them. Then the nautilus was free to swim away.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 5):
A couple of the nautilus' drifted back toward the surface. Emma gently caught one of them and Lara, one of the TerraX.org divers, caught the other. When the two errant nautilus' were released again, at a slightly deeper depth, they started their own decent down. The sight of the clean pink shell floating in the black sea was very beautiful. It looked more like a dramatization of a nautilus in the sea than the real thing, but they were very real and returning to their homes at 200 meters beneath the sea.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 6):
May 6, 1998: Last night we steamed back from Osprey Reef across the Coral Sea. We made two dives on the Great Barrier Reef. The first dive at No Name Reef was full of beautiful coral and fish of every description. The second dive at Snake Pit was a reef that had been devastated, perhaps by a cyclone, and was now beginning to recover. Small islands of live coral were beginning to blossom beneath the sea. The fish were plentiful and the coral quite varied on the oases.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 6):
Our most interesting sightings at Snake Pit were a large (4 ft.) moray eel hiding beneath a plate coral and a ray living in the sandy areas between the reef fingers. The ray wanted to find enough sand to hide himself, too, but he had to swim to several spots before finding an appropriate one. Notice that only the rays eyes are visible when hiding, and that even a couple of fish cannot see him easily.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 6):
During the afternoon we moored in Watson's Harbor on Lizard Island. Here a settler family had been killed by aborigines and a plaque notes the event. Earlier (in 1770) Captain Cook had landed to replenish his water supplies and to climb to the top of the island. He did not climb for the pleasure of the walk. He climbed to get a view of the barrier reefs and possible ship's passages (channels) between them allowing safe passage to the open sea. He was desperate for a way out of the barrier reef which had trapped him against the Australian Coast since he entered the reefs ten weeks before, far to the south. Climbing the mountain did allow him to find safe passage out of the reef.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 6):
Our mission on Lizard Island was strictly pleasure. We climbed to Cook's Look at 840 ft. above sea level, then returned to the beach at Watson's Harbor for a Bar B Que and a contest called Box Biting.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 7):
May 7, 1998: Today's first dive was on a patch reef located between Ribbon Reef # 5 and #6. A bommie just off the reef itself provided excellent variety of coral. The small coral fishes seemed to cluster on the reef itself in less than 10 m (33 ft) of water. Here we saw two dark lionfish (scorpion fish family) and a bright yellow trumpetfish.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 7):
For the second dive, we moved to a similar patch reef between Ribbon # 4 and #3. The big surprise of the day here was to drop immediately down onto a White Spotted Guitarfish resting on the bottom in 20 m (66 ft) of water. This is the shark-looking animal featured in our photo and he was every bit as large as he looks-about 8 ft. long! It was very lethargic and did not mind our coming quite close for photographs. Remember yesterday's ray? That was a Blue Spotted Lagoon Ray. He was about 4 ft long including his 2.5 ft. tail and was quite skitterish until he found enough sand to bury himself.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 7):
The guitarfish is technically a ray but is shaped very much like a shark. He was one of the first types of rays to evolve from sharks. Fossil guitarfish from 35 million years ago look very similar to living guitarfish.

TerraX.org , Coral Sea, Great Barrier Reef (18:27, May 7):
On the third dive, we saw an anemone turn itself inside out! Emma said they do this as a defense when an animal tries to eat their tentacles.

Shawn Steele, Sydney, Australia (19:29, May 9):
We will begin our chat with Andy Dunstan in 1/2 hour. (10:00 AM local time). Andy is the research coordinator with the Undersea Explorer and will talk with us about the Great Barrier Reef and the research missions they do on the Undersea Explorer.

Shawn Steele, Sydney, Australia (19:37, May 9):
20 minutes...

Shawn Steele, Sydney, Australia (19:49, May 9):
The chat will start in 10 minutes

Psyndi, Oregon (19:50, May 9):
Looking forward to this!

Lara Steele, Sydney, Australia (19:56, May 9):
Psyndi, glad you could make it. The times posted are shown in east coast time in the United States. I was hoping that Andy could open by telling us a little about the health of the Great Barrier Reef (GBR)?

Psyndi & Alexis, Oregon (19:58, May 9):
Alexis is here with me, so we will try to have questions for you all!

Lara Steele, Sydney, Australia (19:59, May 9):
Andy I had hoped that this description of the health of the reef could tell us how that is decided as well as how the GBR is doing at the present time.

Andy Dunstan, Far north Queensland (20:00, May 9):
Hi, I'm here and waiting for any questions about coral reefs or the Undersea Exploreradventure diving and research

Psyndi & Alexis, Oregon (20:01, May 9):
What are some of the indicators of the health of the reef?

Lara Steele, Sydney, Australia (20:02, May 9):
Great Andy! Did you see my first question about the health of the reef? (remember to hit "continue" to see the questions)

Lara Steele, Sydney, Australia (20:05, May 9):
Hang on everyone, we may be having technical difficulties on one end of this chat.

Psyndi & Alexis, Oregon, USA` (20:05, May 9):
Are any of the species of life in the reef endangered?

Andy Dunstan, Far north Queensland (20:06, May 9):
Coral reef health is a tricky thing to assess. You need to study a reef over a length of time to see the changes that happen and also have a decent baseline to start with. Video monitoring and then data analysis is the best way now. Some of the things to check are the overall changes in live coral cover species of coral present, such as changes fromhard to soft coral populations or some of the fast growing colonising coral types Also it is useful to look for aspects which affect corals such as predators - crown of thornms starfish, drupeela snails which both eat coral and leave fresh white feeding scars. Algal growth on coral overt an extended period also is a tell tale that there is either increased nutrients favoring algae instead of coral, or the herbivorous fish population has been depleted. Just a few of the things to look for!!!!

Michelle/Kevin, On the 'Net (20:06, May 9):
We are excited to learn about the GBR health, and also whether it is an inhibitor or aide to species diversity?

Lara Steele, Sydney, Australia (20:07, May 9):
Thanks Andy. That sounds like lots of work!

Andy Dunstan, Far north Queensland (20:08, May 9):
A number of species of the reef are affected noit just corals but also some of the megafauna. At present in the SUlawesi, INdonesia area there is a hue fishing effort for whale sharks, pilot whales, mantas and other big marine and reef animals. THese are migratory and it would be easy to almost wiiipe out this population in a couple of years

Psyndi & Alexis, Oregon, USA` (20:08, May 9):
About how long would be a longer enough period to wait and see these changes?

Psyndi & Alexis, Oregon, USA` (20:09, May 9):
I meant long enough, not longer.

Lara Steele, Sydney, Australia (20:10, May 9):
Andy, that sounds scary for the animals health. Can you tell us how many endangered species there are on the reef and what if anything is being done to help them?

Michelle/Kevin, On the 'Net (20:11, May 9):
Andi-- what type of algal growth is indigenous to the GBR habitat?

Andy Dunstan, Far north Queensland (20:13, May 9):
To see reef changes can be as short as a few days if a big warm water blewaching event on shallow water, inshore corals happens (as it just has on the Great Barrier Reef. A few months may see changes due to predation by coral predators and an increase in their population or a movement of their feeding area. Storm and cyclone damage is of course immediate. Thigs like nutrient pollution is a longer term event over a number of years. Often the main problem is not the damage to the reef but how well it can recover. Of nutrients are the problem then they may not recover and algae will take over. Similarly if the fish population is knocked out too much the same will occur. These scenarios are happening in many of the world's reefs now.

Lara Steele, Sydney, Australia (20:14, May 9):
Andy after your next answer lets go back up a bit and pick up some of the earlier questions. One of them was Is the health or the reef "also whether it is an inhibitor or aide to species diversity?"

Steve at BSCS-Colorado Springs, On the 'Net (20:14, May 9):
Andy: Does the present El Nino appear to be affecting the major reef builers (Anthozoans & Hydrozoans) of the Southern Hemisphere?

Psyndi & Alexis, Oregon, USA` (20:15, May 9):
What is megafauna?

Andy Dunstan, Far north Queensland (20:17, May 9):
The algal growth endemic to the GBR is quite varied, including turf, filamentous, encrusting, coralline and macroalgae. These are all a natural part of the reef, but in a 'healthy'system are kept in balance. Normally you would not see much algae on a reef. It is there but is kept grazed right down by the herbivorous fish and invertebrates. Coral cover of live coral also reduces the area available for algae growth on a balanced reef system

Andy Dunstan, Far north Queensland (20:18, May 9):
Megafauna - BIG THINGS - often even called charismatic megafauna because they are often the animals most sought after by divers and snorkellers and often giving the biggest buzz of your diving life. Seeing a whale shark, whale or manata ray in the water is something you never forget.

Michelle/Kevin, On the 'Net (20:19, May 9):
Why is the algal growth not conducive to coral growth?

Lara Steele, Sydney, Australia (20:19, May 9):
I just want to remind everyone that if a question you ask gets skipped to please reask it at a later time. Sometimes we can be overwhelmed with questions and miss a few.

Michelle/Kevin, On the 'Net (20:21, May 9):
Andy-- we apologize- we missed your posted message about the algae-- Thank you for answering.

Andy Dunstan, Far north Queensland (20:22, May 9):
Healthy corals will generally limit the algal growth. While many corals have chemicals and defensive tentacles to compete with other corals and organisms for growth - algae doesn't seem to do the same thing. However given half a chance with coral getting reduced and killed by storm damage, nutrients or other events, the algae will grow. If the reef and water conditions are still healthy the coral will compete with the algae and win to grow back and recolonise during the next spawning season. If it's not good water quality conditions or a balanced system, then the algae wil win

Andy Dunstan, Far north Queensland (20:23, May 9):
No worries Michelle and Kevin, I thought I'd give you a bit more info!

Lara Steele, Sydney, Australia (20:24, May 9):
Here is a question from Steve from earlier Andy: Does the present El Nino appear to be affecting the major reef builers (Anthozoans & Hydrozoans) of the Southern Hemisphere?

Lara Steele, Sydney, Australia (20:25, May 9):
Andy and great info it is too! Everyone remember to hit END, then scroll, if you think that you missed anything.

Michelle/Kevin, On the 'Net (20:25, May 9):
Andy-- thank you. Are the species of coral within the GBR symbiotic with the dinoflagellates (zooxanthellae)?

Psyndi & Alexis, Oregon, USA` (20:26, May 9):
Do you have a picture of crown-of-thornes? My dad says that they were destoying the coral reef a few years ago, and we're wondering if they still are.

Lara Steele, Sydney, Australia (20:28, May 9):
Psyndi, we don't have any pictures for this chat at this time, logistical troubles, but we will try to get pictures posted at a later date in the log. I will try to locate a crown of thorns picture for you, but maybe Andy can describe one for us?

Psyndi & Alexis, Oregon, USA` (20:29, May 9):
Ok, thanks.

Andy Dunstan, Far north Queensland (20:31, May 9):
Sorry I missed this question Steve. The El Nino is very relevant to Anthozoans and Hydrozoans of the GBR. Corals and their relatives in coral reefs are on of theforst indicators of water temperature increaase. During the hottest months the live very close to their temperature limits so a 2 degee celsius increase can kill large areas of coral. This is especially seen in the near surface reef waters and in areas close to land where the coral may already be under some stress (such as fresh water, sediment and nutrient run0off during the hot wet season) The El Nino often seems to be linked to these warm water plumes which have resulted in major bleaching events in many reef systems. The GBR, Fiji, INdonesia, Palau, Maldives and many others have been recently affected. Bleaching is when ther plants within the corals skin are either ejected, or eject themselves, leaving the coral white and generally resulting in death of the coral colony.

Lara Steele, Sydney, Australia (20:32, May 9):
Andy, no problem if you miss a question. That is why I am here :-) I will just reask it and if I miss one then the others here will reask it again.

Psyndi & Alexis, Oregon, USA` (20:34, May 9):
Andy, when the plants eject themselves or are ejected do they re-site themselves elsewhere and begin formation of a new coral colony, or do they die?

Michelle/Kevin, On the 'Net (20:36, May 9):
It is our understanding that algal growth in the reefs are considered to have similar relationships with coral polyp, much like lichen. Is it possible that the algal growth is not actually an inhibitor to the coral growth, but instead an opportunity of the necessary processes for coral regeneration?

Psyndi & Alexis, Oregon, USA` (20:36, May 9):
Pfiesteria has been killing fish in our waters, waters on the East coast, is it a problem where you are?

Steve at BSCS-Colorado Springs, On the 'Net (20:36, May 9):
Andy: The bleaching mechanism you describe is very interesting. Sounds like the water temp is having a primary effect on the symbiotic zooxanthellae and algae, which then affects their coral hosts. Thanks for the info.

Leslie Whitaker, Sydney, Australia (20:40, May 9):
Andy, I think I am not sure wheterh the algae are the same creature as the zoo???? (phtotosynthesizing one-celled plant) that is simbiotic with the coral polyp.

Andy Dunstan, Far north Queensland (20:40, May 9):
When the plants eject themselves they still live. They are actually a dinoflagellate single cell algae. When they are in the coral they have no 'tail' but after they are free living in the water they regenrate the t'tail' and can move around. An earlier question was about impacts and whether this is good or bad for species diversity. In general it is thought that the wide diversity on coral reefs and in particular the GBR is due to continued changing conditions eg Crown of thorns starfish, cyclones etc can damage coral but often mainly the fast growing corals, leaving the slow older corals alive. These may be ways to keep the diversity and not let these fast growing corals take over completely. Also coral disease seems to affect fast growing corals worse. The more different coral types and formations present, the more habitats and food sources and the more niches for other creatures - increasing reef diversity. The trouble with increased impacts such as nutrients is that it swings this balance on way and then there are fewer species suited to the conditions and they dominate, so diversity is reduced

Psyndi & Alexis, Oregon, USA` (20:43, May 9):
It's interesting to know that they continue to live.

Andy Dunstan, Far north Queensland (20:43, May 9):
Hi Leslie the single cell symbiotic plants (zooxanthallae) in the coral are algae but there are also many more types on reefs. The algae which is an indicator of stress and which overgrows coral to dominatoe reefs is multicellular and may be filamentous or like small kelp type algae. Increase in the single celled algae which floats as plankton is also a problem though as it can bloom in abundance and upset other aspects of marine life including the reef

Leslie Whitaker, Sydney, Australia (20:44, May 9):
We just have Andy for another 15 minutes. So lets make sure that we get our questions out there and we will see how many he can answer in that time. Andy, here is another question from earlier -- Pfiesteria has been killing fish in our waters, waters on the East coast, is it a problem where you are

Andy Dunstan, Far north Queensland (20:45, May 9):
We know the zooxanthallae continue to live by lab experiments. 2 weeks ago we had one of the coral bleaching experts, Kirsten Wagner, on board to study bleaching in this area. She has been part of many of these studies.

Steve at BSCS-Colorado Springs, On the 'Net (20:46, May 9):
Leslie: The zooxanthellae are photosynthetic, but have traditionally been classified as animals on anatomic grounds. Many people now consider them to be algae (distant relatives of Chlamy!)

Lara Steele, Sydney, Australia (20:47, May 9):
Andy these are great answers! Leslie is totally right that we only have about 15 minutes left. Or ten now

Psyndi & Alexis, Oregon, USA` (20:47, May 9):
Umm...what is Chlamy?

Steve at BSCS-Colorado Springs, On the 'Net (20:49, May 9):
Psyndi & Alexis: Chlamy, short for Chlamydomonas, is a motile green algae. Cute critter!

Lara Steele, Sydney, Australia (20:49, May 9):
Steve, thanks for the info, can you answer Psndyi's question about what is Chlamy?

Psyndi & Alexis, Oregon, USA` (20:50, May 9):
Thanks, we'll do a sreach on the net for a picture. =-)

Lara Steele, Sydney, Australia (20:50, May 9):
Thanks Steve you are faster then I am :-)

Lara Steele, Sydney, Australia (20:53, May 9):
We are getting closer to the end of the hour, and I don't want Andy to have to stay too long. So any last questions?

Michelle/Kevin, On the 'Net (20:53, May 9):
Steve? We are really curious about the algal classifications that you are suggesting. Can you please give us a zoo. reference related to the animal classification?

Lara Steele, Sydney, Australia (20:54, May 9):
I should have added -- or any questions that we may have missed?

Michelle/Kevin, On the 'Net (20:54, May 9):
Andy-- we are very greatful for your details and patience with our questions!

Andy Dunstan, Far north Queensland (20:55, May 9):
Thanks for all the questions folks and I hope we see you down in Oz for some advetues in the blue!!

Andy Dunstan, Far north Queensland (20:56, May 9):
It's a pleasure

Psyndi & Alexis, Oregon, USA` (20:56, May 9):
Thanks for coming today Andy, it's really interesting to find all this out.

Michelle/Kevin, On the 'Net (20:56, May 9):
Andy-- we would love the opportunity to explore with you again-- either through TerraX.org, or live and in the blue waters!

Lara Steele, Sydney, Australia (20:56, May 9):
Andy, thank you so much for all your insightful answers and information!

Steve at BSCS-Colorado Springs, On the 'Net (20:57, May 9):
Michelle & Kevin: Try the book, Five Kingdoms: An Illustrated Guide to the Phyla of Life on Earth, by Lynn Margulies & Karlene Schwartz. W.H Freeman, 3rd ed. 1998.

Lara Steele, Sydney, Australia (20:58, May 9):
I want to thank everyone for attending and your great questions! This chat is now closed.