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Ocean Research


March 2016 Issue

Allied A-Frame
For RV Sikuliaq

Allied Marine Crane’s innovatively redesigned A-Frame crane has recently been installed aboard the RV Sikuliaq.

The A-Frame’s cross beam rotates freely as it deploys, guaranteeing the load and lighting are properly oriented throughout the entire range of motion. The Allied A-Frame also possesses a unique maintenance pin design that creates an additional degree of freedom to provide an unprecedented 172° range of motion. Rope pass-throughs for tugger winches maximize the operating envelope of the A-Frame, and there are electrical outlets at the cross-beam for ease of powering equipment.

Harmful Red Tide
Effects in Aquariums

Many shore residents and beach-goers are already familiar with the health risks of red tide, or algal blooms along coastlines that can trigger respiratory illness and other effects in people who inhale the toxins the algae release. Scientists report new evidence that similar effects can occur on a much smaller scale among home aquariums.

Aquariums are dynamic mini-ecosystems, and some can release harmful toxins very similar to those that algal blooms release. Some owners have reported fevers, difficulty breathing, flu-like symptoms and other health problems after using hot water to clean their aquariums. Hot water on rocks that harbor algae and other critters creates steam that can then be inhaled.

There is little scientific evidence to shore up the link between aquariums and negative health effects, so researchers developed a method to rapidly test aquariums for toxins. They used their procedure to sample the soft coral and synthetic seawater from a home system when a family in the Netherlands fell ill and was hospitalized 45 min. after cleaning their aquarium. The samples had high levels of palytoxins, which are among the most potent nonprotein marine toxins known and a possible cause of red tide health effects. Although the results don’t prove cause and effect, the findings provide further support for the association.

Wave Gliders for
Whale Shark Research

Whale sharks are a poorly understood species globally. Many unknowns remain about their feeding behavior, life cycle and distribution around the world.

Utila, Honduras, has one of the few, year-round populations of whale sharks. The Whale Shark & Oceanic Research Center (WSORC) in Honduras is trying to answer questions involving migration patterns and population trends, among other issues. Answering these questions might help better protect whale shark populations in the region and ensure continued benefit from their presence in the long term.

In late 2015, WSORC teamed up with Liquid Robotics to start a project using autonomous drones to follow acoustic transmitters tagged on whale sharks. The Wave Gliders can follow transmissions for up to two years. With large data sets being processed on board, and real-time communication to the WSORC office, this enables the creation of records for whale shark’s precise behavior in the Caribbean, from migration routes to feeding behavior and seasonal movements.

Sharks at Risk of Being
Overfished in Hotspots

A new study from an international team of scientists found commercial fishing vessels target shark hotspots in the North Atlantic. The researchers suggest that sharks are at risk of being overfished in these oceanic hotspots. The authors report in the study that catch quotas for sharks by commercial fishers might be necessary to protect oceanic sharks.

From 2005 to 2009, the researchers tracked more than 100 sharks equipped with satellite tags from six different species in the North Atlantic while concurrently tracking 186 Spanish and Portuguese GPS-equipped longline fishing vessels. They found that the fishing vessels and sharks occurred in ocean fronts characterized by warm water temperature and high productivity, including the Gulf Stream and the North Atlantic Current/Labrador Current Convergence Zone near Newfoundland.

About 80 percent of the range for two of the most heavily fished species tracked—the blue and mako sharks—overlapped with the fishing vessels’ range, with some individual sharks remaining near longlines for over 60 percent of the time they were tracked. Blue sharks were estimated to be vulnerable to potential capture 20 days per month, while the mako sharks’ potential risk was 12 days per month.

Warmer Atlantic Could
Trigger Stronger Storms

A new study by a team of scientists led by the University of Maryland’s Earth System Science Interdisciplinary Center (ESSIC) suggests that a warmer Atlantic Ocean could substantially boost the destructive power of a future superstorm like Hurricane Sandy.

The researchers used a numerical model to simulate the weather patterns that created Sandy, with one key difference: a much warmer sea surface temperature, as would be expected in a world with twice as much carbon dioxide in the atmosphere. This simulated warmer ocean generated storms that were 50 to 160 percent more destructive than Sandy.

In the model scenarios, the pool of warm water (greater than 27° C) in the tropical Atlantic grew to twice its actual size. The larger warm pool gave the simulated hurricanes more time to grow before they encountered colder water or land. Because of their longer exposure to the large warm pool, their winds had 50 to 80 percent more destructive power, and brought 30 to 50 percent more heavy rain.

Sandy was most likely a “perfect storm” resulting from a series of improbable coincidences. As such, it’s hard to make definite conclusions about whether and how global warming contributed to Sandy and other recent destructive storms. However, studies like this one can help answer how a perfect storm like Sandy would behave under warmer ocean temperatures.


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