Ask an Explorer

Questions were sent to the science party during this expedition. Selected questions and answers are offered below.

Hi! I live in North Carolina with my mother. I had a question...I am 10 and in 5th grade I wanted to know what you do?

Hello. Thanks for your interest in what we do here. Everyone on the ship has a lot of different jobs, but we all help each other out. Some of the things I've done are go down in the submarine, help sort and save animal and sediment samples from the ocean floor, help collect plankton from the water's surface using a Neuston net, and help collect data about the current and temperature at different water depths. Some other people choose the places where we dive, take pictures of samples, and catch billfish for tagging.

My favorite job so far was going down in the submarine. The submarine has two compartments and I got to sit in the front and decide what we would collect and take back to the ship with us. We collected three starfish, some sponges, and even some corals. We also saw a lot of sharks at the bottom and other animals phosphorescing on our way back up to the ship. Phosphorescing means glowing in the dark, like fireflies. We went down to about 1350 feet, and it was scary at first, but then very exciting.

I hope I've answered your question. These are some of the things that I've done on this cruise and I've had a lot of fun. Please write again if you have more questions. You can write to this address until the cruise is over, and then you can write to denises@biol.sc.edu. Thank you again and stay curious! - Denise Strickland, Univ. of South Carolina

Question from Hallieford, Va. (Mathews Co.): Is it likely that this remarkable, erosion resistant rock formation protruded above the sea surface at any time in geological history? If so, could there be any evidence of terrestial life forms within the rock or is it too hard to have provided any haven for preservation?

Hello! No, there is practically no possibility that the Bump was ever real estate. The shallowest part of the feature is more than 1000 feet below sea level. Even when sea level was extremely low due to the vast ice caps and glaciers 18,000 years ago, the sea surface was only 300 ft or so below its present elevation. The earth's crust subsides (i.e., sinks), but there is no evidence that there has been such extensive submergence of this part of the continental shelf in the last 20 million years - well within the time the Charleston Bump rocks were formed. Good question, though! - Leslie Sautter

Question from Johns Island, SC: Just finished reading your swordfish story, very interesting. I was curious as to what the water temperature is at 1,800 feet?

Thanks for your interest in the swordfish log. It seems that a lot of people have enjoyed this tale. To answer your question, so far we have had two dives at depths to 1,800 feet. The day of the swordfish dive, the submersible traveled from the surface where the temperature was 29.0 C, while the temperature at that depth was 13.6 C. On another dive to a different location on the Charleston Bump, the surface temperature at the beginning of the dive was 29.5 C while the temperature at 1875 feet was 8.8 C. Scientists are very interested in the differences in temperature from the bottom of the ocean to the surface since it tells them so much about how water masses form and disperse, much like weather systems on land. In the case of the Charleston Bump where we are in the middle of the Gulf Stream, the variation in temperature indicates that the Gulf Stream truly is a river of water flowing through the ocean.Thanks for the question, and keep checking in with us as we explore this unique area.

Question from Robin of Lexington School District #4, Swansea SC: How has the weather, if at all, affected your mission?

Weather was definitely a factor during the mission. Safety is extremely important during every mission. That is why the sub crew always checks and rechecks the weather before and during sub dives.

The waves were never particularly large during the expedition. The problems we had resulted from the wind blowing out of the north. The wind blew across the sea surface in a different direction than the wave swell was moving. That results in smaller waves moving in different directions. (Many people say the seastate reminds them of a washing machine.) When that happens, it makes launching and recovering the sub much harder. Unfortunately, this happened several times during the mission and we couldn't dive.

On days we we couldn't dive, we often steamed closer to shore and into shallow water. We hoped that the seas would be calmer in shallower water. Thanks for your question.

Question from Ms. Dwelley's Fourth Grade Students:
We would like to know if your ears pop when you go down for a dive?
Do your nose bleed when in a dive underwater?
How cold is it when you are inside the dive tank?
How does the submersible get down into the water?
Have you seen any jellyfish?

Hi, my name is Steve Stancyk, and I'm one of the scientists on the Charleston Bump 2003 cruise. I'm collecting many of the invertebrates, and my speciality is starfish and brittlestars. You have asked some good questions. Here are some answers:

We would like to know if your ears pop when you go down for a dive?

No, they don't. but both chambers are close to surface atmospheric pressure. However, when you come back to the surface, you have to equalize the inside/outside pressure, and when they open the hatch, your ears do pop a little.

Do your nose bleed when in a dive underwater?

No - it's quite comfortable and there is no pain (unless you hit yourself in the nose with your clipboard, of course.

How cold is it when you are inside the dive tank?

The front of the sub is very comfortable, about 70 degrees F - you can even wear shorts and a t-shirt and not get cold. In the back, it's colder, because the hull is just aluminum. Once you are on the bottom, the temp. in the back is the same as outside. Here on the bump, that's about 59 degrees F - long pants, socks, and a sweatshirt make it more comfortable.

How does the submersible get down into the water?

Once the sub is closed up, they lift it off the deck with a huge A-frame. The A-frame swings out over the water right behind the ship, and a big line, about 6 inches thick, slowly lowers the sub into the water. It's kind of scary, because you can see the ship's propellers turning right in front of you. Once both chambers have made sure they aren't leaking, the pilot tells the ship's crew, and they release the line. Then the ship floats away and you begin to submerge. Usually, little fish come swimming right up and follow you for about 100 feet.

Have you seen any jellyfish?

We've seen a few, but they are so clear they are hard to see in the water. In the dark, we can flash the lights and all the other jelly animals in the water (chain-like things called siphonophores, comb jellies, and jellyfish) all flash back at you. It's really cool, like a light show with flashes of green spots all around.

Thanks for looking at our web site, and feel free to ask more questions. Best wishes, Steve

Question from Lou: Just read your daily log on lionfish. I saw lionfish on almost every dive I made last summer; on one dive I saw three. This was at about 100 feet. I have not seen any this year as of yet (have dived the same spot as last year 5 or 6 times so far), but on all the dives I have experienced a thermocline at about 60 ft. with a temperature drop of 10 to 15 degrees. I've also seen a lot less tropicals and overall less fish than last year.

Thanks for sending your observations on lionfish. Water temperatures offshore this year are unusually cool because of persistent SSW winds and above-average rain. The SSW wind causes the surface water to move offshore, and it is replaced by cool deeper water that is upwelled on the continental slope and transported shoreward. The excessive rain causes a lot of runoff from the rivers. As the outflow meets the sea, it moves southward and offshore, and this also help pull deeper water onto the continental shelf to replace the southward flow. Surfers, divers, swimmers and fishermen have all reported cooler water temperatures this year, and several news and weather web sites have reports. A good web site is: Earth Observatory at NASA

Cooler offshore temperatures have resulted in some fish kills in Florida, and may explain reports of decreased numbers of tropical fishes off the Carolinas. Thanks again for your interest in Ocean Exploration and our work on lionfish.

Question from Peter: Which genus or species of coral is featured in the August 6th log image taken at 1,647 feet and how large are those specimens? Itís a really interesting image. Do you have any close ups you can post from the video? I would like to know more.

Jeremy here! I just talked to the coral guy onboard. He actually doesn't know the genus or species but he's going to send it on for DNA testing when he gets back to shore. All of the specimens are just a few inches tall. I'll go through and see if we have any close-ups of some of those. I'm sure we do, it's just a matter of finding one.

Fred Andrus from the Savannah River Ecology Lab is going to run some isotope analyses on the coral back at shore. His email is andrus@srel.edu.

Question from Jason of Fort Dorchester High School, Charleston SC: What was it like when the swordfish attacked the boat? Does the bump create any waves to surf?

The swordfish attacked the sub during the first dive on the Charleston Bump mission. Apparently it got its bill stuck in the side of the submersible and it had to shake free before swimming away. I was not in the sub at the time, but can imagine that it was awesome to feel the power of the fish as it shook the sub. I think the Bump is too deep to create waves that we might surf. It really appears to affect the deep ocean currents more than the waves at the shore.

Question from Colt of Fort Dorchester High School, Charleston SC: Is there some type of net that you can use to capture the red lionfish? How would you go about capturing it?

We have tried to capture the lionfish using the suction hose and the claw on the manipulator arm of the sub. So far the lionfish we have seen have eluded capture. This might not be a bad thing because I don't want to be the one to have to deal with an angry venomous lionfish when we bring it up to the surface! Actually, we would make preparations to make certain we were not injured by the fish long before it ever came up in the sub.

Question from Josh of Fort Dorchester High School, Charleston SC: Do you ever try to eat the crabs found on your observations after observing each crab captured?

Josh, we don't eat any of the specimens we collect. They are all preserved for future study. It is awfully difficult to get specimens of many of these organisms so we are very careful with them. Sometimes we loan them to other researchers. At the North Carolina Museum of Natural Sciences we have specimens from the late 1800s which are still being used by the research staff.

Question from Jesse of Fort Dorchester High School, Charleston SC: Does the Johnson-Sea-Link ever get stuck on the coral while doing observations of the Charleston Bump? Thanks for you time, hope everything goes well at the Charleston Bump. The sub pilots try to avoid knocking against the coral. I don't think it would get stuck very easily, but we don't want to destroy what we have come to study. We do take small samples to bring back to the lab. Question from A. Davis of Fort Dorchester High School, Charleston SC: I would like to know if you have any plans for sending any additional submersibles besides the Johnson-Sea-Link down to investigate the Bump? Thank you. Every scientist works with several organizations to secure submersible time. The team that just finished has worked with the JSL previously and I would guess that they would want to continue working with the same team. Other research groups might want to use other equipment. It is important to match the capabilities of the sub with the goals of the research.

Question from Allie of Fort Dorchester High School, Charleston SC: After being out at sea for so long, do any of you still get sea sick? What are your living quarters and conditions like on the tending vessel?

Allie, seasickness tends to strike within the first 24 hours on a ship. When you first get on board your body has to become accustomed to the constant rocking of the ship. After a while you develop "sea legs" and your body adapts to the rocking and you don't really even sense it anymore. It can be hard to walk on deck, climb the stairs, or even read (and work on the computer!) before then. Even people who have been to sea many times might get sick before they get their "sea legs." There are medications and other things available to help prevent seasickness. Plus it is important to stay well hydrated, get enough sleep, and avoid foods that might upset your stomach anyway. It is funny too to return to land. You have almost the same feeling as you try to walk on the ground that is not moving, or sleep in a bed that is not rocking. It has taken me up to a week to get my "land legs" completely back! Life at sea is quite comfortable. We have plenty of hot and cold water, air conditioning, and electricity on board. Our cabins have bunks and most cabins have adjoining "heads" or bathrooms. The excellent cook prepares our meals in the galley. If needed, we can even do a load of laundry. We work long days (usually 12-hour shifts), but during our "off hours" people read, write in their journals, work on projects and papers or simply watch the waves and look for dolphins.

Question from Kristina of Fort Dorchester High School, Charleston SC: On average, how much seafood do you eat after a dive? What is the deepest dive site you have been on in the past? Have you ever witnessed a fish eating another fish? If so, what kinds?

Kristina, what we eat after a dive depends on what the cook has prepared. We don't eat what we collect. All of those specimens are kept for future study by the scientists. Watching the life under the sea does not influence my enjoyment of seafood!

In 2001, I had the privilege of diving off Cape Hatteras, NC. We descended 2,950 feet along the edge of the continental slope. It was very cold and dark and we saw unusual animals like Wolf Eel Pouts. My favorite part of the dive was watching the incredible bioluminescence as we ascended. You can read more about it by going to the Ocean Exploration website and looking at Islands in the Stream 2001 logs. Although that I know there are plenty of fish that eat other fish, I don't think I have ever watched one do it. Most of the time I have seen fish eating coral or searching along the bottom for a crustacean.

Question from Dora of Fort Dorchester High School, Charleston SC: If you had the choice, would you of used a different submersible? Are there any other types of bumps anywhere else?

Dora, there are not that many research submersibles in the world. We have used both the Johnson-Sea-Link and the Johnson-Sea-Link II for previous work. It is good to have established a working relationship with the subs crew and to know the capabilities of the sub itself. Of course we have to see what is available and see what we can afford. Different subs can go to different depths or perform specific maneuvers. I don't think we would have used a different sub. I am certain that there are other "bumps" out there that might influence the movement of water, but I don't know if they have been pinpointed on a map. The Charleston Bump really covers an area with several different features.

Question from Jessica of Fort Dorchester High School, Charleston SC: How are your sleeping habits at sea? Is it more relaxing or uncomfortable on the boat? Are the sunsets really pretty? Has this experience been spiritual for you? Thanks.

Jessica, at sea your sleeping habits are determined by your watch. If you work during the day you sleep at night, BUT if you work at night you sleep during the day. It can be difficult to adjust back to the normal routine when you get home! Both the sunsets and the sunrises can be spectacular at sea. I particularly enjoy seeing the oranges reds and yellows reflected in the deep blue of the deep ocean. I have heard about seeing a "green flash" when the sun sets into the sea but have not seen it out here yet. Being at sea helps me remember how truly insignificant we are, and how all things are connected. Life at sea it dictated by the weather and the seas.

Question from Ariel of Fort Dorchester High School, Charleston SC: On airplanes, my ears start to hurt b/c of the pressure. Does that happen on the sub? Thanks.

Ariel, it is obvious from your question that you know there is a change in air pressure when you go up in an airplane or over a mountain. The submersible is kept at a constant 1 atmosphere pressure so our ears don't pop. The walls of the sub are quite strong to withstand the great pressure of the deep ocean.

Question from George of Charleston SC: Why do deep water amphipods have large red eyes?

George, both deepwater amphipods and shallow water amphipods have large red eyes. Although we don't know the exact use of the eyes, they must be useful for something or we would not find them both places. One idea is that the eyes help them see the bioluminescent organisms - some of which they might want to eat and some of which they might want to avoid.

Question from Elizabeth of NC: Have you found new species of fish and were they bioluminescent?

Hi Elizabeth. We have just started the "Life on the Edge" expedition and have not had a chance to catch too many things yet. While we are out at sea, we don't have much time to identify everything we have caught. Usually it takes us about a year to complete the identifications of the fish and invertebrates from one 10 day mission. Sometimes however we can tell immediately that we don't recognize a fish. Last year we caught a few "records" or things that had never been found off the coast of the Carolinas. The year before we found three fish that might be new to science.

Question from Anonymous: How did the upwelling or thermocline off the Florida Coast form?

What is happening are unusual sustained winds blowing east. These winds blow the surface waters, which are heated by the sun, offshore. When these warm waters blow offshore the colder water below is drawn up and heated and moved off shore in turn. This is exactly how the classic equatorial upwellings work, which recycle nutrients from deep waters and drive the productivity of the oceans. What we might expect to happen in the larger picture might be the Gulf Stream moving slightly farther off shore, cold water bottom fish being caught close inshore, out of the cold water zone (offshore or laterally), fewer sunbathers and more surfers wearing wetsuits.