Tag: scuba diver

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Thomas Nassif, July 24, 2005

NOAA Teacher at Sea
Thomas Nassif
Onboard NOAA Ship Nancy Foster
July 15 – 24, 2005

Mission: Invasive Lionfish Survey
Geographical Area: Southeast U.S.
Date: July 24, 2005

The SCUBA invention has extended the reaches of human exploration from land to the deep-sea.
The SCUBA invention has extended the reaches of human exploration from land to the deep-sea.

Weather Data

Latitude: 34°10’N
Longitude: 76°39’W
Visibility: 10 nautical miles (nm)
Wind direction: 34°
Wind speed: 13 kts
Sea wave height: 2′
Swell wave height: 2-3′
Sea water temperature: 30°C (86°F)
Sea level pressure: 1016.5 mb
Cloud cover: 2/8, cumulus, cirrus

Science and Technology Log 

The last dive of the research cruise couldn’t have been more exhilarating. Unfazed by the gusty winds, choppy seas, and ripping ocean currents, the divers explored one last shipwreck on the ocean floor. The Naeco was a U.S. tanker that was destroyed by a Nazi U-boat during WWII. The torpedo shattered the Naeco’s bow and stern into two pieces, sinking them to the ocean bottom nearly 7 miles apart. The divers returned to the surface with stories about the stern (back) of the Naeco and thrilling reports of lionfish of every size and number.

The more I think about my experiences aboard the Invasive Lionfish Cruise, the more I begin to see two parallel themes here: the deep-sea diver and the lionfish. Human action led to the introduction of lionfish into a foreign habitat, but at the same time, one person invented the SCUBA, which introduced humans to the mysteries of the deep-sea.

Thomas Nassif interviews Casey Coy on the dive deck for his video documentary on lionfish and deep-sea divers.
Thomas Nassif interviews Casey Coy on the dive deck for his video documentary on lionfish and deep-sea divers.

Lionfish can only swim so far north of their tropical paradise in the southeastern Atlantic before the temperature becomes too cold, whereas humans can only dive so deep before the pressure of the sea becomes too great. Lionfish have scales for protection, fins for locomotion, gills for respiration, and swim bladders for buoyancy. SCUBA gear makes it possible for humans to be like fish, even if it adds 200 lbs to your body! They include a BCD (buoyancy compensator device) to control buoyancy, wet suits for protection and insulation, fins for underwater movement, and regulators attached to tanks for respiration. But lionfish are different from most fish because of their venomous spines that make  them the “ultimate survivors” in their new habitat. Similarly, SCUBA divers are equipped with high-tech gear that may not be familiar to most people, yet it helps humans to survive and explore the underwater environment.

“The bow of the ship left traces of beautiful pigments on the sky’s canvas, an eternal embrace between the first ember of light and a lucid sky.”
“The bow of the ship left traces of beautiful pigments on the sky’s canvas, an eternal embrace between the first ember of light and a lucid sky.”

Yet there is one difference between lionfish and humans that became most apparent over the course of my cruise. Whereas lionfish may harm the local ecosystem by lowering the number and diversity of native fish in the Atlantic, deep-sea divers are in a unique position to help our society by increasing our knowledge and creating a better understanding of the importance of preserving native habitats.

Reflections…

On the final morning of the cruise my eyes met a resplendent sunrise that shot stars across the shimmering waters of an endless sea. As we headed to the east I grew quiet within… the bow of the ship almost seemed to leave traces of beautiful pigments on the sky’s canvas, an eternal embrace between the first ember of light and a lucid sky. Land  is but hours away, but the memories of this journey will never leave my mind.

Who could forget such a fascinating, diverse group of personalities; Paula the lionfish enthusiast, Doug underwater photographer extraordinaire, Jay and the underwater hunt, Casey and the underwater flex, Christine the lion queen, Roldan king of transect, and last but certainly not least, Joe and the quest for Choco-tacos.

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Thomas Nassif, July 22, 2005

NOAA Teacher at Sea
Thomas Nassif
Onboard NOAA Ship Nancy Foster
July 15 – 24, 2005

Mission: Invasive Lionfish Survey
Geographical Area: Southeast U.S.
Date: July 22, 2005

A lionfish and two lobsters pose for the camera at Lobster Rock. Today the divers collected a total of 23 lionfish from this dive site.
A lionfish and two lobsters pose for the camera at Lobster Rock. The divers collected a total of 23 lionfish

Weather Data

Latitude: 33°38’N
Longitude: 76°55’W
Visibility: 10 nautical miles (nm)
Wind direction: 240°
Wind speed: 13 kts
Sea wave height: 1-2′
Swell wave height: 2-3′
Sea water temperature: 28.9°C
Sea level pressure: 1018 mb
Cloud cover: 6/8, Cumulus, Altocumulus

Science & Technology Log  

Today the divers explored Lobster Rock, collecting a total of 23 lionfish for the flow through aquarium aboard the ship. Water from the ocean flows into and out of the tank yhrough pipes on the deck to simulate the ocean environment. This brings the total laboratory aquarium at Beaufort.

Today I also interviewed the Chief Scientist, Paula Whitfield. Most amazing to me was how her life story evolved from a childhood fascination with Jacques Cousteau to her current passion for lionfish research. Paula grew up watching the underwater videos of Jacques Cousteau, and it was at that point that she knew she wanted to become a diver. “I was a diver first, but the more I dove, the more I was formulating questions in my mind…I was curious about everything that had to do with water and marine life.” She worked for a sea grass ecologist for many years, not running the show, but she saw how the scientific process worked. Her desire to become a marine biologist grew stronger,  and that’s when she decided to return to school to get her graduate degree.

Recently collected lionfish from the ocean floor are transferred to a flow through aquarium aboard the ship.
Recently collected lionfish from the ocean floor are transferred to a flow through aquarium aboard the ship.

So how did Paula become one of the leading scientists in lionfish research? She responds: “It stemmed from my recreational diving – I was diving constantly in my spare time, and working for a charter boat business that attracted recreational divers from all over the world.” And then one day she began seeing lionfish off the coast of North Carolina, which was very unusual for this area. Paula knew they were Pacific fish, but she needed proof that lionfish were now in the Atlantic. “From that point on, I collected evidence was finally able to convince NOAA when a world-renown scorpion fish expert confirmed that her collected specimens were lionfish.

Once Paula was aboard a diving ship, and she was ordered to do a routine dive to the ocean bottom. The first thing she saw was right angle patterns, which hardly exist in nature. All of the sudden Paula saw a porthole lying in the sand. Back then she wasn’t a technical diver with all the fancy gear she has today. So she clutched the porthole with her knees and climbed up the anchor line. When Paula reached the surface, everyone aboard the ship stared at her in disbelief when she said: “I think it’s a wreck. I have a porthole.” She fondly remembers feeling “excited to be the first person to dive a virgin shipwreck.”

Diver and Marine Biologist Paula Whitfield swims alongside a lionfish, the focus of her research.
Diver and Marine Biologist Paula Whitfield swims alongside a lionfish, the focus of her research.

What Paula finds most fascinating about lionfish is how they established themselves in such large numbers in the Atlantic within a short period of time. Because of this she calls lionfish the “ultimate survivors.” But overall, she feels very affectionate towards all sea creatures, including “everything from sea spiders and feather dusters to larger fish because it’s such a different world down there. It’s important for us to know how we’re affecting that world in order to make a positive change.”

Paula’s words of advice for those who want to become marine biologists: “I think it’s important if you can become a diver – just to be able to put your head in the water to see what’s going on is more rewarding than just dropping sensors into the ocean. It opens more doors, and by seeing the environment firsthand you are able to formulate more questions about it. All this helps you become a better marine biologist, even if you don’t dive all the time.”

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Thomas Nassif, July 21, 2005

NOAA Teacher at Sea
Thomas Nassif
Onboard NOAA Ship Nancy Foster
July 15 – 24, 2005

Mission: Invasive Lionfish Survey
Geographical Area: Southeast U.S.
Date: July 21, 2005

Thomas Nassif on the Bridge gathering measurements from the ship’s weather log.
Thomas Nassif on the Bridge gathering measurements from the ship’s weather log.

Weather Data

Latitude: 33°30’N
Longitude: 77°09’W
Visibility: 10 nautical miles (nm)
Wind direction: 290°
Wind speed: 15 kts
Sea wave height: 3′
Swell wave height: 3-5′
Sea water temperature: 28.9°C (84°F)
Sea level pressure: 1019.9 mb
Cloud cover: overcast, cumulus and stratus

Science & Technology Log

The day began with rocky seas, gusty winds, strong ocean currents, and the tallest swells we’ve had since our departure from port last week.  These ocean conditions are nothing extraordinary for the ship’s crew, but extremely tough for the divers.  The diving site for this morning was Southeast Tower 2, not far from the old Frying Pan Tower that was used by the Coastguard to collect and transmit ocean conditions.  The Tower’s location 35 miles off the Atlantic coast atop a 45-foot deep rock formation made it among the most valuable navigational aids for collecting ocean data such as wave height and water temperature.

The 187-foot NANCY FOSTER in the Atlantic. The Bridge is located on the very top level of the ship.
The 187-foot NANCY FOSTER in the Atlantic. The Bridge is located on the very top level of the ship.

The first dive of the morning went smoothly.  But the second dive team was not so fortunate. After jumping off the ship they were swiftly pulled past the dive site buoy by strong ocean currents. Having missed the dive site, the divers ended up at an entirely different location on the ocean floor! This is why it is so important for ships to record the weather conditions and their location at sea.  These measurements take place on the Bridge, the command center of the ship.

Every day, I walk to the Bridge to get the weather data that appears at the top of my daily logs. Here is an explanation of the terms:  Latitude tells you how far north or south you are from the equator (which is 0° latitude), while Longitude tells you how far east or west you are from Greenwich, England (0° longitude).  Together, Latitude and Longitude give the exact location of the ship. Visibility is how far ahead you can see from the ship.  On a very foggy day you may only have a visibility of 10 feet, whereas on a clear day you can see all the way to the horizon, or 10 nautical miles.  Wind direction tells you which way the wind is blowing from – 0° is north, 90° is east, 180° is south, and 270° is west. Sea wave height and Swell wave height are height estimates of the smaller ripples and larger waves, respectively. Sea level pressure (or barometric pressure) indicates what the trend of the weather has been. High barometric pressures (like today – 1019mb) usually mean sunny weather; rain cannot build up in clouds if they are being squeezed together by high pressure. Low barometric pressures tell you that rain or stormy weather is on the way. Inside the eye of a hurricane barometric pressures can be as low as 875mb!  Under low pressures clouds can expand and fill up with rain.  Cloud cover is a number between 0 and 1 that describes how much of the sky is covered with clouds.  4/8 means that half of the sky is covered with clouds, 1/8 means very few clouds, 7/8 is mostly clouds, and overcast (or 8/8) is all clouds.

A lionfish has many fins. The outstretched pectoral fins are not venomous. The shorter, pointier spines are venomous. From right to left they are: dorsal, pelvic, and anal spines. Photo courtesy of Christine Addison.
A lionfish has many fins. The outstretched pectoral fins are not venomous. The shorter, pointier spines are venomous. From right to left they are: dorsal, pelvic, and anal spines. Photo courtesy of Christine Addison.

Every day the ship sends all of this weather information to the National Weather Service (NWS) by satellite.  The NWS will in turn fax this information to other ships that will be traveling in our area so they can get a better idea of what the weather is like at our location. And when our ship steams ahead to a new dive site tomorrow, we will be grateful if another ship was in the same area.  The weather information that ship collected will help us know more about the weather!

Question of the day

How many sets of venomous spines do lionfish have?  Where are they found on its body?

Lionfish (like most fish) have five different types of fins.  But in Lionfish, some fins have sharp, venomous spines. The dorsal (back), pelvic (waist), and anal fins all have pointy, venomous spines that look like injection needles. The caudal and pectoral fins, on the other hand, are not venomous and look more like ordinary fish fins.

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Thomas Nassif, July 20, 2005

NOAA Teacher at Sea
Thomas Nassif
Onboard NOAA Ship Nancy Foster
July 15 – 24, 2005

Mission: Invasive Lionfish Survey
Geographical Area: Southeast U.S.
Date: July 20, 2005

A underwater photograph of the City of Houston shipwreck. Over time the ribs of the ship’s hull have been covered by sponges (pink fluff) and soft coral (colorful branches). Tomtate fish are pictured to the right.
A underwater photograph of the City of Houston shipwreck. Over time the ribs of the ship’s hull have been covered by sponges (pink fluff) and soft coral (colorful branches). Tomtate fish are pictured to the right.

Weather Data

Latitude: 33°38’N
Longitude: 76°55’W
Visibility: 10 nautical miles (nm)
Wind direction: 240°
Wind speed: 13 kts
Sea wave height: 1-2′
Swell wave height: 2-3′
Sea water temperature: 28.9°C
Sea level pressure: 1018 mb
Cloud cover: 6/8, Cumulus, Altocumulus

Science & Technology Log  

My excitement and fascination with this entire diving expedition grew even more when I heard that the divers would be exploring two shipwreck sites on the ocean floor today – “18 Fathom” in the morning and “City of Houston” in the evening. Fathoms are an old unit of measurement still used by navigators today to describe the depth of the ocean (1 Fathom = 6 feet deep). The dive site “18 Fathom” is a mystery shipwreck that was discovered at a depth of 108 feet (18 Fathoms). Shipwrecks provide excellent habitats for a variety of fish, including lionfish. The broken down hull and old passageways of a  shipwreck create a manmade reef upon which algae and coral grow, smaller fish hide, and larger fish feed. Rather than scrap old ships, many countries around the world clean and sink their old ships to the ocean floor to create artificial reefs for fish and other marine organisms.

An explosion of Tomtate (white fish) and Vermilion Snapper (red fish) envelop the water in a silvery red glow.
An explosion of Tomtate (white fish) and Vermilion Snapper (red fish) envelop the water in a silvery red glow.

After lunch, the boat steamed ahead to the next dive site, City of Houston. Far beneath the ocean surface looms an old Civil War Era shipwreck. Thousands of fish including Tomtate, Vermilion Snapper, and Silverside enveloped the divers, making the surrounding waters shimmer with silvery red. At times the number of fish were so great that the divers had trouble seeing even a few feet in front of them! Over one  hundred years after the City of Houston wrecked and fell to the seafloor, you can now see coral and algae taking over the entire manmade structure. Even so, it is still possible to make out obvious structures of the ship, including the engine and the hull.

Personal Log 

Today I went snorkeling off the NF4 once again and had a fantastic time swimming in the 84°F water under a beaming sun – It’s unbelievable that the Atlantic Ocean can be so warm during the summer months! Also, I’ve watching the divers in action as they descend to the ocean floor, collect live lionfish, and take stupendous photos of the deep ocean all inspire me to someday become a professional SCUBA diver myself.

Question of the day

What type of air do SCUBA divers breathe?

This depends on how deep you plan to dive. Regular air (the kind we breathe on land) is mostly nitrogen and only 21% oxygen. The tanks that the deep-sea divers carry on their back are filled with regular air, and they can dive up to 150 feet by breathing this air through a mouthpiece (or regulator). Other divers that only need to dive up to 113 feet (like our safety divers) use Nitrox, which has more oxygen (36%) than regular air. Finally, at depths up to 20 feet deep, SCUBA divers can breath pure oxygen (100%). The deep-sea divers on our cruise switch to pure oxygen 20 feet before they reach the ocean surface to speed up their decompression.

The two dangers with SCUBA diving and the air they breathe are:

1 – Too much oxygen can be toxic to your body. The deeper you dive, the less oxygen you should have in the air you breathe. 2 – At the same time, too much nitrogen can make you feel light-headed and put you to sleep underwater. Jacques Cousteau, French inventor of the SCUBA, called this “Rapture of the Deep.” That is why it is so dangerous for divers to spend too long in the deep ocean.

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Thomas Nassif, July 19, 2005

NOAA Teacher at Sea
Thomas Nassif
Onboard NOAA Ship Nancy Foster
July 15 – 24, 2005

Mission: Invasive Lionfish Survey
Geographical Area: Southeast U.S.
Date: July 19, 2005

“A fiery ball of radiant yellow…penetrated the hues of deep blue and wispy whites.”
“A fiery ball of radiant yellow…penetrated the hues of deep blue and wispy whites.”

Weather Data

Latitude: 33°38’N
Longitude: 76°55’W
Visibility: 10 nautical miles (nm)
Wind direction: 240°
Wind speed: 13 kts
Sea wave height: 1-2′
Swell wave height: 2-3′
Sea water temperature: 28.9°C
Sea level pressure: 1018 mb
Cloud cover: 6/8, Cumulus, Altocumulus

Science & Technology Log  

Today was by far the most beautiful sunrise we’ve had since our departure from land last week. A fiery ball of radiant yellow captured the sky, as its luminous rays penetrated the hues of deep blue and wispy whites in the surrounding sky. This morning the divers visited Kinny 1 and 2 (also known as K1 and K2). But this was no ordinary dive… K2 happened to be the most challenging and strenuous dive yet. The ocean currents were moving faster than we expected. The ship pulled up-current from the dive site (marked by an orange buoy), to put the divers in position. All they would have to do is jump off the ship and drift down-current to find the buoy. But when the divers jumped off the ship they were swept away by the strong ocean currents well past the buoy. The NF4 picked up the divers, who had to take off all 200lbs of their SCUBA gear, and wait to be taken to the correct diving site. The divers eventually finished their mission at K2, but were very exhausted when they returned to the NANCY FOSTER.

Thomas Nassif aboard the NF4 dive boat. The NANCY FOSTER is pictured in the background.
Thomas Nassif aboard the NF4 dive boat. The NANCY FOSTER is pictured in the background.

Today I finally got my chance to step off the NANCY FOSTER for the afternoon. I boarded the NF4 (diver recovery boat) and we steamed off into the open sea. Soon thereafter we watched from a distance, as the divers leap off the NANCY FOSTER. Our job was to keep an eye on the divers to ensure their safety during the 130-foot descent to the ocean floor. The NF4, along with the NANCY FOSTER and RHIB, all bear the “divers flag” when we deploy SCUBA divers into the ocean. This red flag with a diagonal white stripe warns other ships in the immediate area that there are divers in the water.

I also went snorkeling in the ocean to watch the SCUBA divers decompress underwater. After the divers finished their dive to the ocean floor, they stopped at 20 feet from the ocean surface to breath pure oxygen from a long tube supplied from the surface by the RHIB (the air we breathe everyday is only 21% oxygen). If the divers chose instead to shoot straight up to the ocean surface, they risk getting the “bends,” a painful experience that occurs when nitrogen bubbles form in the blood.

The divers safely returned to the ship with 6 lionfish in their nets – the aquarium aboard the NANCY FOSTER now has a total of 25 live lionfish! The scientists plan to transport them to a more permanent home at the NOAA Beaufort Laboratory when we arrive at port next week. To simulate the natural conditions of the ocean, scientists will place the lionfish in a “flow through aquarium” that transports ocean water through a pipe into and out of the aquarium. By having several aquaria full of lionfish in the lab, scientists hope to learn more about their diet and how often they reproduce.

Question of the day

Do lionfish reproduce in the same way as fish? How often do they reproduce?

Yes – Lionfish reproduce like most fish, through External Fertilization. Eggs are released from the female into the water and then fertilized by sperm from a male fish. The thing that makes lionfish so different from most fish is this: Female lionfish release a floating mass of eggs that stick together (most fish release eggs that disperse and spread out from each other in the water). Scientists think that lionfish are more successful at reproducing because the floating masses of eggs are more likely to be fertilized. We do not know how often lionfish reproduce – this is one of the biggest questions scientists want to find out! The reproductive periods of fish overall can be very different. Some species of fish, like Salmon, reproduce only once in their entire lifetime. Tropical organisms like the Parrotfish, on the other hand, reproduce every day! It will be very helpful for us to know how often female lionfish reproduce so that we may better understand their impact on the local ecosystem.

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Thomas Nassif, July 17, 2005

NOAA Teacher at Sea
Thomas Nassif
Onboard NOAA Ship Nancy Foster
July 15 – 24, 2005

Mission: Invasive Lionfish Survey
Geographical Area: Southeast U.S.
Date: July 17, 2005

Deep-sea diver Christine Addison takes a leaping plunge into the ocean off the deck
Deep-sea diver Christine Addison takes a leaping plunge into the ocean off the deck

Weather Data

Latitude: 34°43’N
Longitude: 76°42’W
Visibility: 10 nautical miles (nm)
Wind direction: 200°
Wind speed: 11 kts
Sea wave height: less than 1 foot
Swell wave height: none
Sea water temperature: 87 F, 30.5°C
Sea level pressure: 1017.9 mb
Relative Humidity: 86%
Cloud cover: 2/8, Cumulus, Stratocumulus, Cirrostratus

Science and Technology Log

Early this morning at 0545 hours the NANCY FOSTER arrived at her next two dive locations (SEPAPNEW1 and SEPAPNEW2), 34 nautical miles due south of Beaufort Inlet. We are traveling along the Atlantic Continental Shelf, which runs along the Western boundary of the Gulf Stream. I asked the Chief Scientist, Paula Whitfield: “Why do all of our dive sites fall along the border rather than in the heart of the Gulf Stream? Since the water is much warmer in the Gulf Stream wouldn’t we be far more likely to see Lionfish since they are a tropical fish?” Paula informed me that further east of us the ocean depth drops to about 300 feet, beyond the maximum depth (150 feet) our SCUBA divers could reach. Furthermore the Gulf Stream currents would pose many risks to the divers – even a 1-2 knot current is enough to rip off a diver’s mask. Paula carefully chooses the dive locations using a bathymetric map of the ocean floor (similar to a topographic map for land).

The NF4 (shown in front) is transporting divers back to the ship after a successful dive. The RHIB (shown behind) carries an oxygen manifold that delivered pure oxygen to the divers during their ascent from the ocean floor.
The NF4 (shown in front) is transporting divers back to the ship after a successful dive. The RHIB (shown behind) carries an oxygen manifold that delivered pure oxygen to the divers during their ascent from the ocean floor.

Several things must happen before the SCUBA divers actually jump off the boat. First, drop buoys are deployed into the water to mark the exact location of each dive site. A drop buoy basically consists of bright orange buoy that floats on the ocean surface to let the ship know where the divers are located. To hold the orange buoy in the same location, it is attached to an anchor and a 10-lb weight by a 150-ft cord that sinks to the ocean floor. The drop buoy also helps the divers orient themselves during their descent to the ocean floor. By following the bright yellow cord during their descent, the divers can reach the exact dive location on the ocean floor.

The next step is to deploy two small boats, the RHIB (Rigid Hull Inflatable Boat) and the NF4. The RHIB holds the oxygen manifold, which supplies pure oxygen to the SCUBA divers after they finish their dive and begin their gradual ascent to the ocean surface (divers must decompress or wait at 20 feet below the ocean surface after their dive to ensure they acclimate to the change in pressure). The NF4 is a larger more sturdy boat used to recover the divers and bring them back safely to the ship.

Finally the divers are ready to jump off the ship, and this is no easy task. Imagine having to jump off the side of the ship with 200 pounds of SCUBA gear strapped to your back. Most of this weight is due to two enormous air tanks that deep-sea divers must carry to ensure they have enough air to

Personal Log

Today was an extremely busy day! Somehow the dive teams were able to squeeze in 4 different dive locations on the ocean floor in the same day – 2 dives in the morning and 2 dives in the afternoon. This time the divers were equipped with nets to capture live Lionfish and spear guns to collect dead Lionfish. The divers returned to the ship with 19 Lionfish! Amazingly, they collected 17 live Lionfish and stored them in the holding tank aboard the ship. The scientists performed a dissection on the remaining two Lionfish (that arrived to the ship already dead). Watching the dissection made me realize that the internal anatomy of the Lionfish is no different from any other fish (except for their venomous spines of course!)

Question of the day

Are Lionfish edible?

Jose, I must admit that I answered your question incorrectly at the Carnegie Institute summer course…Yes (to my surprise) Lionfish can be eaten, and their venomous spines have no harmful affects when ingested. In fact, some members of the scientific team have tasted Lionfish, and described the white meat of the fish as chewy, not tender, and a bit fishy tasting. Hopefully I will have the opportunity develop a recipe for Lionfish curry before the cruise is over.

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Thomas Nassif, July 16, 2005

NOAA Teacher at Sea
Thomas Nassif
Onboard NOAA Ship Nancy Foster
July 15 – 24, 2005

Mission: Invasive Lionfish Survey
Geographical Area: Southeast U.S.
Date: July 16, 2005

Underwater photograph of a lion fish taken by Doug Kesling, deep-sea diver on the NANCY FOSTER.
Underwater photograph of a lion fish taken by Doug Kesling, deep-sea diver on the NANCY FOSTER.

Weather Data

Latitude: 34°43’N
Longitude: 76°42’W
Visibility: 10 nautical miles (nm)
Wind direction: 200°
Wind speed: 11 kts
Sea wave height: less than 1 foot
Swell wave height: none
Sea water temperature: 87 F, 30.5°C
Sea level pressure: 1017.9 mb
Relative Humidity: 86%
Cloud cover: 2/8, Cumulus, Stratocumulus, Cirrostratus

Science and Technology Log

After the final computer tests, our ship finally left for sea today at 1310 hours. The NANCY FOSTER steamed ahead through choppy waters to the first dive site of the Lionfish study, “210 Rock.” The dive site is located 27 nautical miles off the coast of Cape Lookout, North Carolina. At 1800 hours four SCUBA divers leaped off of the starboard side of the ship in search of Lionfish. They were equipped with two underwater video cameras and two waterproof clipboards to record their observations. The divers leaped off the boat and dove to the ocean floor (to a depth of 108 feet) to tally the number of Lionfish compared to other native species of fish within a given distance (this is called a visual transect survey).

Thomas Nassif helping on deck to deploy a drop camera that sends real-time video footage of the deep sea to the ship’s television monitors.
Thomas Nassif helping on deck to deploy a drop camera that sends real-time video footage of the deep sea to the ship’s television monitors.

Now for a brief interlude…

What are Lionfish and why are we taking the time to study them? Lionfish are members of the scorpion fish family that are not native to the Atlantic Ocean. Organisms like the Lionfish that arrive, survive, and successfully reproduce in an ecosystem where they did not previously exist are called an invasive species. Lionfish are a very colorful fish with venomous spines originally from the Indo-Pacific coral reefs of southeastern Asia. Ever since their accidental release into the Atlantic Ocean in 1992, Lionfish have reproduced quickly and established themselves in increasing numbers along the Atlantic Coast from Florida to North Carolina. Lionfish are ambush predators that use their venomous spines to paralyze and swallow whole fish (baby shrimp, snapper, and grouper). For this reason, their presence in the Atlantic may negatively impact the local ecosystem and pose a vital threat to the commercial fisheries industry.

Back to the divers…

Upon their return to the ship from 210 Rock, the divers discovered 10 Lionfish, all of them juveniles, approximately 20 cm. in length. Lionfish have been reported in the vicinity before, but not until recently. This suggests a possible Lionfish migration into the area from the warmer waters of the Gulf Stream several miles away in the Atlantic (Lionfish can only survive in warmer, more tropical water temperatures). Now for some good news: The divers saw an impressive variety of native fish including Adult Gag, Scamp, Red Grouper, Blue Angel Fish, Soap fish, Spotfin Hogfish, Spanish Hogfish, White Grunt, Bank Sea Bass, Black Sea Bass, Almaco Jack, and Spade Fish. All of this suggests that the ecosystem near 210 Rock is biologically diverse, vibrant, and healthy. Hopefully it will remain that way, despite the looming threat of the Lionfish in the horizon…

This map clearly shows the Gulf Stream in the Southeastern Atlantic (look for a dark red streak off the coast of Florida). Darker reds are the warmest ocean temperatures, blues are the coldest.
This map clearly shows the Gulf Stream in the Southeastern Atlantic (look for a dark red streak off the coast of Florida). Darker reds are the warmest ocean temperatures, blues are the coldest.

Personal Log

I was relieved that we were able to get at least one dive off today, despite our ship’s delayed departure. Most amazing was the video footage that the divers brought back onboard the ship – they captured several Lionfish on video, hidden beneath rocks and carefully camouflaged in their background environment. Watching the video makes me realize that the ocean floor is a dramatically different landscape than what we are accustomed to on land!

Question of the Day

Should we worry about Lionfish closer to shore along the beaches of the Atlantic Coast? Is their sting venomous enough to kill a person?

Luckily for us, a venomous spine from a Lionfish is not enough to kill a person, but they can cause a painful sting. You will also appreciate the fact that Lionfish will probably never invade beaches along the Atlantic coastline. This is because temperature limits their distribution in the Atlantic. The Gulf Stream is a warm current of the Atlantic Ocean that originates in the Gulf of Mexico and runs northeastward along North America. Because the Gulf Stream remains several miles offshore from the Atlantic coastline, these waters can remain somewhat warm during the winter, despite frigid inshore water temperatures. This is why Lionfish can survive in the Gulf Stream (where it is warmer in the wintertime) but not closer to the coast (where winter water temperatures are far colder). Additionally, Lionfish cannot survive north of Cape Hatteras, North Carolina due to the colder water temperatures along the northeastern Atlantic coastline. For this reason, scientists consider Cape Hatteras a “Zoo-geographical boundary” beyond which Lionfish cannot stay alive.