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Species Profile – Giant Isopod

November 22, 2010
Underside of the Giant Isopod, Bathynomus giganteus, showing its heavily armored covering and numerous legs.

Underside of a Giant Isopod. Photo by R. Peyton Hale.

On a recent night sample, there were gasps of both delight and horror when the ship’s fantail lights illuminated one of the samples. I was, unfortunately, already in my bunk and so missed it when they brought up a Bathynomus giganteus, a Giant Isopod. This thing looks like the stuff of horror movies to some, or nature in the extreme to us naturalist types. The Giant Isopod is related to the sow bugs so familiar to us back home (aka pill bugs, roly-poly, and many other common names), but it looks like a mechanical one on steroids. In fact, it doesn’t even look real and it reminds me of something we would sell at the Museum store during our annual BugFest event.

But real it was. Ours was medium-sized, probably 8–10 inches in length and 4–5 inches wide (it might fit in a shoe box, maybe). I have read reports of some monsters reaching over 2 feet in length! A head-on view looks like a heavily armored vehicle in some sci-fi movie. Giant isopods have been found in depths from 200 to over 2000 m. They are believed to feed on dead whales, squid, fish and other material that fall into the depths in addition to devouring slow moving prey such as sea cucumber, sponges, and other creatures found on the deep-sea floor.

Giant Isopod, Bathynomus giganteus, showing its heavily armored covering.

Head-on view of a Giant Isopod. Photo by R. Peyton Hale.

Females have a brood pouch, or marsupium, formed by overlapping plates on their underside. The fertilized eggs are huge — up to 0.5 inches — and are believed by some to be the largest eggs of any known marine invertebrate. Young are retained in the brood pouch until they emerge looking like miniatures of the adults (young isopods are known as mancae).

 

Head view of Giant Isopod, showing the compound eyes, each of which has an estimated 4000 facets.

Head view of Giant Isopod, showing the compound eyes, each of which has an estimated 4000 facets. Photo by R. Peyton Hale.

Giant isopods were first discovered in 1879 at a time when there was still debate whether there was life in the deep ocean. I can only imagine what stories must have been told about this seemingly alien creature from the depths back then if it evokes the variety responses I saw on board our ship the next day. And if, in its strange appeal, it garners interest in (and hopefully more awareness and concern for) these deep-sea environments from those that might not otherwise care, then the Giant Isopod is a worthy ambassador.

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Species Profile – Cutthroat eel

November 21, 2010
Cutthroat eel brought from about 250m off the Florida coast.

Cutthroat eel. Photo by Art Howard.

The dive site Thursday was a relatively shallow one for this mission (~250 m) but one that has been suspected to have species characteristic of greater depths. This may be explained by extremely cold water at this site — perhaps from upwelling of colder waters from deeper areas nearby — although no one knows for sure. Indeed, the ROV recorded deep-water species such as Lophelia corals and several Cutthroat Eels. The eels were spotted near some coral and were moving about in their characteristic sinuous swimming motion, staying near the corals that were gently waving in the current. The scientists decided to collect them as we had not yet collected any fish on this mission. The method chosen to collect these slender fish was to use the ROV’s suction hose (aka slurp gun). The suction hose looks like a large dryer hose that you can find at your local home improvement store, but this one is attached to a multi-million dollar machine. To collect a specimen using the hose, the manipulator arm grabs a handle on the hose and directs it toward the intended specimen. One of the crew inside the van pilots the arm while another controls the suction.  When the time is right, the crew coordinate a giant gulp by Jason and the specimens are swept into a multi-chambered collection bucket monitored by a video camera. Inside the van, everyone can see whether the collection was successful.

Cutthroat eel showing the bluish color that is so beautiful on this species.

Cutthroat eel. Photo by R. Peyton Hale.

The data is recorded and the specific collection bucket that the target was sucked into is logged and sealed.

The collection bucket rack is then rotated so a fresh bucket is ready for the next specimen. The suction hose is quite useful for delicate specimens or for quick ones that are tough to grab with the manipulator arms.

The eels are beautiful, bluish-silver in color, and range in size from 146-188 mm total length.

Cutthroat eel head close-up

Cutthroat eel head. Photo by Mike Dunn.

Cutthroat eels are in a family of eels (Synaphobranchidae) found worldwide in temperate and tropical seas. They are bottom-dwelling fish, found in deep waters down to about 3,700 meters (12,100 ft). The specimens collected during this mission will be taken back to the lab at UNCW as voucher specimens for this locale and habitat.

Species Profile – Brittle Stars

November 21, 2010
Brittle star central disk top surface

Brittle star with one missing arm. Photo by Mike Dunn.

Brittle stars are aptly named — when specimens are brought into the lab for us to photograph they are generally missing arms. We always get blamed, but our response always is, “they came to us that way, honest.” Seems their arms tend to fall off when touched by a scientist or grabbed by a predator.

Brittle star arm

Brittle star arm. Photo by Art Howard.

Brittle stars, or ophiuroids (ophis means snake in Greek), are echinoderms and are closely related to starfish. They crawl across the seafloor or in coral or rubble using their flexible arms for locomotion.  The movement of their arms is indeed snake-like. They generally have five long, slender, whip-like arms, which may reach up to 24 inches in length on the largest specimens.

Luckily for them, in spite of being fragile, ophiuroids can readily regenerate lost arms or arm segments. They use this ability to cast off an arm in a way similar to how some lizards deliberately shed part of their tails to escape and confuse predators. Some brittle stars are also able to emit a green light when disturbed. Each arm is supported by a central internal skeletal support (ossicle). Like starfish, brittle stars have tube feet, but those of brittle stars lack suckers. The tube feet help more with feeding than with locomotion.

Brittle star - underside of disk

Brittle star - underside of disk. Photo by Art Howard.

The central disk of ophiuroids contains all of the internal organs of digestion and reproduction.  So, unlike starfish, these organs are never found in the arms of brittle stars. Look closely at the underside of the disk. The star shape is from the five moveable jaw segments surrounding the mouth. Ophiuroids are generally scavengers or detritivores. Small organic particles are moved into the mouth by the tube feet. They may also prey on small crustaceans or worms. The paired sacs between each arm are called bursae. These are the primary sites for gas exchange and excretion in brittle stars. In some species, the bursae are also used as brooding chambers for developing larvae.

ROV Data

November 20, 2010
View of the ROV van controls inside the van showing many of the monitors used to view the depths at which the ROV Jason is working.

View of the ROV van control room. Photo by Art Howard.

In the ROV control center, referred to as the “van,” there are three tasks that the science crew performs The lead scientist determines to which locations the ROV will be moving and indicates which specimens are to be collected. The event logger records specimens collected and other items of interest during the dive. The DVD manager monitors DVDs and the hard drive used to record the entire dive. During any dive, at least three of the ROV crew are also present in the van and they monitor Jason’s systems and manipulate the mechanical arms.

When entering the van, one immediately sees over 20 video screens mounted to the walls. Masses of wires and cables are neatly arranged throughout the room. Virtual reality style gloves used for manipulating the ROV’s arms sit at the pilot’s seat. It is amazing to think about the amount of time and expertise put into developing, building, and arranging a technological feat such as the Jason ROV and its van.

Beverly at the DVD controls in the ROV van

Beverly at the DVD controls in the ROV van. Photo by Jana Thoma.

Tonight my role in the ROV van was the DVD manager. While this sounds like a seemingly simple task, there is a lot of room for error. Thankfully I had some guidance in preparing for this task. I had second watch, the afternoon shift, so my time frame was from 2–8 pm.

I arrived at the van a little bit early, so I could be brought up to speed on the timing of the video recordings. The role of DVD manager isn’t just pressing the record button on a DVD recorder. That would be too easy. First of all, there are twelve DVD recorders that must be monitored at the same time. Then, there is the high definition video hard drive that must be recorded hourly to prevent file sizes from being too large. Data must then be logged into two separate spreadsheets. The DVD start and stop time, mission number, and dive site is recorded on paper and in digital form. This information is also recorded for the hard drive. Then labels containing this information must be printed and put onto six DVDs, two each for the Pilot Cam, Science Cam, and Brow Cam. Now imagine recording all of this information in Zulu time. For example, 2:00 pm would not be 14:00 as it would be in military time, but would be 19:00 in Zulu time.

Although managing the DVD’s was a bit confusing at first, I quickly got the hang of it. Having a role to play in the ROV van made me feel as if I was part of the larger context of data management for marine research. During the Extreme Corals Expedition, I have gotten to be a part of active field research and have seen how important recording data is. I have helped label sponge and Gorgonian specimens collected and recorded information for genetics research. Recording videos on DVD and the hard drive in the ROV control center doesn’t sound like a really important task, but without this video, scientists would not have information about their specimen’s natural environment and habitats.

Musings from the bow

November 20, 2010
Another beautiful sunrise at sea

Another beautiful sunrise at sea. Photo by Mike Dunn.

A couple of days ago it hit me how much time I had been spending in the confines of the main science lab. I have been in the lab almost constantly since arriving on the ship either photographing specimens or trying to write and post blogs through the temperamental Internet connection. I decided I need to get back in touch with who I really am- the guy that likes to walk in the woods, to observe nature. The logical thing was to go out on the deck, especially the bow of the ship. I remember before going on the Arctic research trip several years ago, someone asked me if I would get bored looking at ice all day. The answer was a resounding no. One of the scientists on board that trip explained it best — he compared it to watching a campfire, something that almost everyone seems to enjoy. It is mesmerizing, always changing. Time spent on deck here is similar…no day is the same weather-wise, no two waves alike — the weather, wind, and light are always changing.

So, now I am a regular at sunsets (usually a few folks out) and sunrises (never crowded). Guess that is one reason I like sunrises so much. It gives me some time to think. What better way to set the tone for the day and to be thankful for whatever the day brings.

This deck ritual has become one of my daily routines here on the ship. Others include food, attempts at sleep, performing Ninja style moves to get in and out of the top bunk, and the one phrase we all can’t wait to hear, “ship’s stoooooorrrreee is open!”  The ship’s store is a small closet stocked with all the essentials of life at sea  — canned nuts, toiletries, and clothing for the discriminating (ship t-shirts, socks, patches, and hats). And as important as the goods are, the store is also the best source of change – for the quarters and dollar bills necessary to get sodas, candy, and chips from the vending machines. These provisions are the staple of late night science-at-sea when samples are brought on board.

The food on board has been great. It is amazing the variety of food that the incredible kitchen staff prepares for us — last night was pork, seafood paella, and roast duck as the main entrée choices. There is always salad, veggies of some sort, rice or potatoes, and dessert. The meals are served at regular times: breakfast 7–8; lunch 11–noon; dinner 4:30–5:30 with accommodations made for those on the night shift. And since there are more people on board than there are seats in the galley we are encouraged to heed the words on the straightforward sign above one of the tables, “eat it and beat it.”

Night before last I went out on the bow after dark. We were advised to let someone know if you go out on deck after dark as they keep lights to a minimum to make it easier for those on watch on the bridge to see the ocean and horizon. And indeed, when you first go out, it is really dark.  But the moon was bright and my eyes soon adjusted. I laid down on what seems to be the favorite perching spot on the ship — a large “box” covered in lines used in docking. It was incredibly peaceful. I found myself watching clouds passing in front of the moon. Thoughts of woods and waterways back home drifted into my head. I started looking at the sky, at how bright Jupiter is, even with the bright moon sharing the sky. I watched the clouds change color as they passed in front of the moon. Then I noticed one of the clouds had a strong resemblance to a Squat Lobster and the ocean wave patterns reminded me of the swirls of icing on the carrot cake. Hmmm, perhaps I have been on the ship too long….

Scientist Spotlight: Martha Nizinski

November 20, 2010
Dr, Marha Nizinski, an invertebrate specialist on the Deep Sea Corals expedition.

Dr. Martha Nizinski

Martha Nizinski graduated from West Virginia Wesleyan College with a bachelors of science degree in biology. She received her master’s degree in zoology from the University of Maryland and her Ph. D. from William and Mary’s Virginia Institute of Marine Science. Martha presently works for the National Ocean and Atmospheric Association (NOAA), National Marine Fisheries Service in a research lab (National Systematics Lab) housed at the Smithsonian’s Natural History Museum. Prior to this, she worked in the fish collection at the Smithsonian.

Martha is participating in the Extreme Corals Expedition to study invertebrates, such as crustaceans. Crustaceans, such as crabs and lobsters, are   animals with exoskeletons. Martha’s research interests are taxonomy and community ecology. On many research cruises she has been the only scientist aboard studying invertebrates. Her research focuses on determining what kind of animals can be found in and around cold water coral areas. Many of her research cruises have extended from North Carolina south to Florida and into the Gulf of Mexico.

The most important part of her research is to first identify the specimens. While conducting research, Martha also takes tissue samples from the abdomen of each specimen. These tissue samples are used for genetics. The genetic research will help determine variability within and between populations living within cold water coral areas and to see how closely related the crustaceans are. This also helps to show how the populations might be connected throughout their geographic ranges.

Another tissue sample is taken for isotope analysis. This is used to study the trophic dynamics, or food webs, in these habitats. This isotope data helps explain which organisms crustaceans eat and what organisms eat crustaceans.

In addition to tissue samples, the video data recorded by the Jason ROV is useful in learning about the ecology of crustaceans. The DVD recordings may be viewed several times to observe where specific crustaceans were collected. When viewing these animals in their natural habitat, Martha can learn more about them. The video allows her to see where the crustaceans live and to analyze different habitat associations. Do they live deep within the coral? Do they hide under the coral?  Are they only found on one particular kind of coral?

Martha enjoys studying crustaceans because they are such a diverse group that includes animals like the squat lobsters, golden crabs, and spider crabs. “The diversity of them is just amazing.”

As a child growing up in the mountains of western Maryland, Martha enjoyed family vacations to the beach and loved visiting the ocean. In college, Martha had the opportunity to take a course in marine biology and her parents were very supportive. During this course, the participants lived on a sailboat in Key West and studied marine biology. After that, Martha was hooked!

“To be part of projects like this is pretty amazing,” Martha states. “You should never lose sight of what a great opportunity this is to be able to see these amazing animals alive in their natural habitats.”

Interview with Martha (mp3)

Species Profile – Crinoids

November 19, 2010
A crinoid, or feather-star, captured in deep waters off Florida.

This crinoid is one of the free-swimming species called comatulids. Photo by Art Howard.

Crinoids, also known as sea lilies or feather-stars, are marine echinoderms of the class Crinoidea. The name comes from Greek for “lily-like” in reference to their resemblance to a flower. They have a cup-shaped body (called a theca) with five or more feathery arms (rays) and, in some species, a segmented stalk for attachment to a surface. Theca and rays are together called the crown. The arms contain reproductive organs and sensory tube feet. Most of the body consists of an endoskeleton made up mainly of articulated series of calcareous pieces (ossicles) held together by connective tissues.

 

 

 

 

 

Crinoid cirri act as tiny feet to help them move and cling to surfaces.

Crinoid cirri act as tiny feet that help the animal cling to substrates. Photo by Mike Dunn.

The majority of living crinoids are free-swimming and have only a vestigial stalk. The one we caught was one of the free-swimming species, known as comatulid crinoids. They swim by flapping their arms. They also have small curved “feet” called cirri that they use for movement. Once the animal finds a suitable perch, it uses its cirri to hold itself in place.

 

 

 

 

A close-up viwlooking into the body of a crinoid highlights the radial arms they use to capture food and swim through the water.

Looking down into the body of a crinoid. Photo by R. Peyton Hale.

Crinoids are filter feeders. The tube feet are covered with a sticky mucous that traps tiny bits of organic matter suspended in the water. The food is then transported inward, down the length of the arms to the mouth.

There are only a few hundred known modern forms, but crinoids were much more numerous both in species and numbers in the past.