Friday, June 20, 2008


ROV Finds New Coral Species

Researchers on the third-largest atoll in the world, the Saba Bank in the Netherlands Antilles, have discovered and collected two new species of soft corals (gorgonians) and documented severe anchor damage with the aid of a Remotely Operated Vehicle (ROV) from Seabotix. Experts from Texas A&M University-Corpus Christi, Universidad de los Andes in Colombia, and the Rosenstiel School of Marine and Atmospheric Science at the University of Miami collected 40 species of soft corals, seventeen of which were collected using the ROV.

The SeaBotix LBV200L is rated to 200m (656 ft.) and includes fiber optic video, LED lighting, and powerful brushless thrusters. An optional grabber arm was used to collect the deepest new soft coral species at 70 m (230 ft.), a depth that would be impractical to explore using conventional diving techniques. Shelley Lundvall, Project Coordinator for the Saba Bank project, said, “The LBV (ROV) has helped us explore the deeper areas of the bank that nobody has seen before. We have also been able to add to the species diversity of gorgonians found on the Saba Bank”.

The ultimate goal of the research is to receive official recognition of the Saba Bank as a Particularly Sensitive Sea Area (PSSA) from the International Maritime Organization (IMO) in order to regulate international shipping that occurs within the Exclusive Economic Zone of the Netherlands Antilles. A management plan is now being drafted with the goal of enforcing existing and new regulations to protect the incredible diversity of Saba Bank marine life.

Another discovery emphasised the importance of the PSSA designation: “One of the most dramatic moments was when we found an anchor and chain scar on the bottom...The ability to document the damage done by these large ships is critical in getting the Saba Bank designated as a Particularly Sensitive Sea Area”, commented Shelley.

The video of this significant damage, as well as the actual recovery of the soft corals can be seen at

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Thursday, June 19, 2008


Mediterranean Sharks Declining Fast

Thresher sharkA new scientific study has concluded that sharks in the Mediterranean Sea have declined by more than 97 percent in abundance and “catch weight” over the last 200 years.

The findings of the study published in the journal Conservation Biology, suggest several Mediterranean shark species are at risk of extinction, especially if current levels of fishing pressure continue. Study lead author Francesco Ferretti and his colleagues are concerned that the declines in sharks may have implications for the broader Mediterranean marine ecosystem.

Ferretti said: “The loss of top predators such as sharks in other sectors of the Atlantic has resulted in changes to the ecosystem. These changes are unpredictable and poorly understood but given the decline in Mediterranean shark numbers, there is cause to be seriously concerned about the effects this could have.”

Forty-seven species of sharks live in the Mediterranean Sea, of which 20 are considered top predators.

The study authors only had enough information to assess the status of five of the twenty large predatory shark species in the Mediterranean. Of those analysed, almost all of the large sharks have decreased in abundance because of unintended capture in open ocean fisheries, targeted shark fishing, and human population pressure in coastal areas. Sharks are especially vulnerable to overfishing and slow to recover from depletion because they generally grow slowly, mature late and produce few young.

The mean size of sharks caught in the Mediterranean is among the lowest in the world. The study reveals that size and weight declines over time indicate that more young and immature sharks are being caught.

There are currently no catch limits for commercially-fished shark species in the
Mediterranean Sea. A comprehensive monitoring program for fisheries has been difficult to implement in the Mediterranean because of the artisanal (small and localized) nature of its fisheries and the large number of countries bordering the sea.

Only five species of sharks offered sufficient information for analysis, including the blue shark, one thresher shark species, two mackerel shark species and one hammerhead shark species. The blue, smooth hammerhead and thresher sharks were classified as “Vulnerable” according to the latest IUCN-World conservation Union Red List Criteria for extinction risk. Two mackerel sharks, porbeagle and shortfin mako, were classified as “critically endangered”. Many other large sharks are classified as “Data Deficient”.

To view a summary of the Conservation Biology paper, visit:
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Tuesday, June 10, 2008


Robot fish may track whales or pollution

In the world of underwater robots, new Robofish are a team of pioneers. While most ocean robots require periodic communication with scientist or satellite intermediaries to share information, these can work cooperatively communicating only with each other.

In the future, ocean-going robots could cooperatively track moving targets underwater, such as groups of whales or spreading plumes of pollution, or explore caves, underneath ice-covered waters, or in dangerous environments where surfacing might not be possible. Schools of robots would be able to work together to do things that one could not do alone, such as tracking large herds of animals or mapping expanses of pollution that can grow and change shape.

Over the past five years Kristi Morgansen, a University of Washington assistant professor of aeronautics and astronautics, has built three Robofish that communicate with one another underwater. Recently at the International Federation of Automatic Control's Workshop on Navigation, Guidance and Control of Underwater Vehicles she presented results showing that the robots had successfully completed their first major test. The robots were programmed to either all swim in one direction or all swim in different directions, basic tasks that can provide the building blocks for coordinated group movement.

This success in indoor test tanks, she said, will eventually provide the basis for ocean-going systems to better explore remote ocean environments.

"Underwater robots don't need oxygen. The only reason they come up to the surface right now is for communication," Morgansen said. Her robots do not need to come to the surface until their task is complete.

Co-authors on the recent study were UW doctoral students Daniel Klein and Benjamin Triplett in aeronautics and astronautics, and UW graduate student Patrick Bettale in electrical engineering. The research was supported by grants from the National Science Foundation and the Air Force Office of Scientific Research.

The Robofish, which are roughly the size of a 10-pound salmon, look a bit like fish because they use fins rather than propellers. The fins make them potentially more maneuverable and are thought to create lower drag than propeller-driven vehicles.

But while other research groups are building fishlike robots, what's novel with this system is that the robotic fish can communicate wirelessly underwater. Again, Morgansen looked to natural systems for inspiration. The engineers worked with collaborator Julia Parrish, an associate professor in the UW's School of Aquatic and Fishery Sciences, to record patterns of fish schools' behavior.

"In schooling and herding animals, you can get much more efficient maneuvers and smoother behaviors than what we can do in engineering right now," Morgansen explained. "The idea of these experiments (with schools of live fish) is to ask, 'How are they doing it?' and see if we can come up with some ideas."

The team trained some live fish to respond to a stimulus by swimming to the feeding area. The scientists discovered that even when less than a third of the fish were trained, the whole school swam to the feeding area on cue.

"The fish that have a strong idea tend to dominate over those that don't," Morgansen said. "That has implications for what will happen in a group of vehicles. Can one vehicle make the rest of the group do something just based on its behavior?"

Beyond finding the optimal way to coordinate movement of the robots, the researchers faced major challenges in having robots transmit information through dense water.

"When you're underwater you run into problems with not being able to send a lot of data," Morgansen said. State of the art is 80 bytes or about 32 numbers per second, she said.

The energy required to send the information over long distances is prohibitive because the robots have limited battery power. What's more, signals can become garbled when they reflect off the surface or off of any obstacles.

Messages were sent between the robots using low-frequency sonar pulses, or pressure waves. The new results showed that only about half the information was received successfully, yet because of the way the Robofish were programmed they were still able to accomplish their tasks. Robots that can independently carry out two simple sets of instructions--swimming in the same direction or swimming in different directions--will allow them to carry out more complicated missions.

Now researchers are using the fish's coordination ability to do a task more similar to what they would face in the ocean. The Robofish pack's first assignment, beginning this summer, will be to trail a remote-controlled toy shark.

Further reading: Autonomous Underwater Multivehicle Control with Limited Communication: Theory and Experiment

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Thursday, June 05, 2008


Scientists Announce Top 10 New Species

Scientists at the International Institute for Species Exploration have put together a list of the Top 10 New Species described in 2007.

Number one on the list is a sleeper ray called Electrolux addisoni. It was thus named as the discovery of this brightly patterned electric ray "sheds light (Latin, lux) on the rich and poorly known fish diversity of the Western Indian Ocean. And the vigorous sucking action displayed on the videotape of the feeding ray may rival a well-known electrical device used to suck the detritus from carpets and furniture in modern homes".

Coming in at number 8 is the Box Jellyfish, Malo kingi. This new species is the second known species of the dangerous box jellyfish genus Malo, one of several genera of irukandji jellyfish. It is named after American tourist Robert King, who apparently died after being stung by the species while swimming off northern Queensland, Australia. King’s death was a pivotal point in irukandji management, raising public awareness about safety.

The top ten were selected by an international committee of experts, chaired by Dr. Janine Caira of the University of Connecticut. These species were selected from the thousands of species described in calendar year 2007.

The taxonomists are also issuing a SOS – State of Observed Species report card on human knowledge of Earth’s species. In it, they report that 16,969 species new to science were discovered and described in 2006. The SOS report was compiled by ASU’s International Institute for Species Exploration in partnership with the International Commission on Zoological Nomenclature, the International Plant Names Index, and Thompson Scientific, publisher of Zoological Record.

“The international committee of taxon experts who made the selection of the top 10 from the thousands of species described in calendar year 2007 is helping draw attention to biodiversity, the field of taxonomy, and the importance of natural history museums and botanical gardens in a fun-filled way,” says Professor Quentin Wheeler, an entomologist and director of ASU’s International Institute for Species Exploration.

“We live in an exciting time. A new generation of tools are coming online that will vastly accelerate the rate at which we are able to discover and describe species,” says Wheeler. “Most people do not realize just how incomplete our knowledge of Earth’s species is or the steady rate at which taxonomists are exploring that diversity. In 2006, for example, an average of nearly 50 species per day were discovered and named.

“We are surrounded by such an exuberance of species diversity that we too often take it for granted. Charting the species of the world and their unique attributes are essential parts of understanding the history of life and is in our own self-interest as we face the challenges of living on a rapidly changing planet,” Wheeler says.

The announcement fell on the anniversary of the birth of Carolus Linnaeus, who initiated the modern system of plant and animal names and classifications. The 300th anniversary of his birth was celebrated worldwide in 2007 and this year marks the 250th anniversary of the beginning of animal naming.

The majority of the 16,969 species described (named) in 2006 were invertebrate animals and vascular plants, which according to the SOS report is consistent with recent years and reflects, in part, “our profound ignorance of many of the most species-rich taxa inhabiting the planet.”

There are about 1.8 million species that have been described since Linnaeus initiated the modern systems for naming plants and animals in the 18th century. Scientists estimate there are between 2 million and 100 million species on Earth, though most set the number closer to 10 million.

According to the authors of the SOS report: “There are many reasons that scientists explore Earth’s species: to discover and document the results of evolutionary history; to learn the species that comprise the ecosystems upon which life on our planet depends; to establish baseline knowledge of the planet’s species and their distribution so that non-native pests and vectors of disease may be detected; to inform and enable conservation biology and resource management.

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