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Environmental Monitoring


August 2016 Issue

Award for Combatting
Invasive Species

Trojan Marinex has been named the winner of the 2016 Outstanding Private Sector Achievement award from the Reduce Risks from Invasive Species Coalition (RRISC). The award recognizes Trojan’s environmental stewardship and proven ballast water treatment technology.

Over 90 percent of the world’s trade is carried by sea, and each year an estimated transfer of over 10 billion tonnes of ballast water takes place worldwide. Untreated ballast water can result in the introduction and spread of aquatic invasive species, threatening local environments.

Listening for Whales
In New York Bight

Scientists working for the Wildlife Conservation Society, New York Aquarium and the Woods Hole Oceanographic Institution have successfully deployed a hi-tech acoustic monitoring buoy in the New York Bight to listen to whales.

The buoy is located between two major shipping lanes entering New York Harbor and is connected to a weighted frame 125 ft. below on the seafloor that carries an acoustic instrument that records and processes sound from a hydrophone. Data are transmitted from the instrument to the buoy then to shore through the Iridium satellite system.

This technology allows monitoring of the presence of several species of baleen whales in near real time to help better understand when and where whales are present in New York’s waters, particularly where there is little information on how whales are affected by ship traffic and ocean noise.

High Temp Increase
Detected in Ligurian Sea

A surprisingly high temperature increase at intermediate depths in the Ligurian Sea, between Corsica Island and the Liguria-Tuscany coast, was detected by CMRE gliders during the recent LOGMEC (Long-term Glider Missions for Environmental Characterization) environmental campaign.

Ocean gliders are green underwater vehicles that propel themselves by changes in their weight and have very long endurance. The campaign marked the longest ever uninterrupted CMRE deployment in Italian waters: 55 days and 1,454 nm covered by three gliders.

The LOGMEC preliminary results reveal temperature increases around 200 m depth with values 0.5 to 1.0° C above those previously measured between 1970 and 2014. Early analysis of wider area data appears to indicate that this anomalous warming event could have been caused by the boost in temperature of intermediate waters coming from the Tyrrhenian Sea and originating in the eastern Mediterranean.

At deeper levels, the data confirmed the recently discovered rising trend of temperature and salinity levels of the Levantine Intermediate Waters (LIW, coming from the eastern Mediterranean).

If confirmed, these results would demonstrate that in some years’ time the climate variability of the eastern Mediterranean could influence the northwestern Mediterranean Sea, with greater impacts on intermediate and deepwater (and, consequently, on marine ecosystems) than previously assumed.

Whale, Winghead Sharks
Now Endangered

New IUCN Red List assessments reveal that growing human pressures on whale sharks and winghead sharks are putting these species at an increasing risk of extinction. Whale sharks and winghead sharks are now listed as endangered.

Numbers of whale sharks (Rhincodon typus), the world’s largest living fish, have more than halved over the last 75 years as they continue to be fished and killed by ship propellers.

Although conservation action in India, the Philippines and Taiwan has ended large-scale fishing of whale sharks in these countries, they continue to be fished in other locations, including southern China and Oman. As whale sharks and tuna are often present together, they are frequently caught by fishers targeting tuna.

Unregulated fishing is also behind the fast-falling numbers of the winghead shark (Eusphyra blochii), whose morphology makes it extremely vulnerable to entanglement in fishing nets. This species of hammerhead shark has moved from near threatened to endangered on the IUCN Red List.

Toxic Algae Sludge
Needs Management

Florida’s Treasure Coast has turned toxic this summer, as a foul-smelling algae bloom that resembles guacamole has made some beaches untouchable. One cause is the controlled release of water from an over-full Lake Okeechobee into local rivers that flow east to the Atlantic and west to the Gulf of Mexico, World Resources Institute (WRI) explained. Heavy precipitation makes these controlled releases necessary because Lake Okeechobee’s aging dike system can’t retain the large amount of water.

The lake’s poor water quality starts with its surrounding watershed, or drainage area, which is agricultural land that is planted with citrus and sugarcane and has hundreds of thousands of acres of pasture. Rains carry fertilizers and manure into the lake, and ultimately to the coast. Fertilizer, manure and sewage are loaded with nutrients, nitrogen and phosphorus, leading to eutrophication. The fertilizer feeds algal growth in water, resulting in harmful algal blooms.

Besides disrupting tourism, these blooms can cause health problems—such as nausea, respiratory issues and skin irritations—for humans who come in contact with the water. The algae can also choke out marine life by blocking sunlight and consuming oxygen that fish and other aquatic species need to survive. When oxygen levels become dangerously low, or hypoxic, dead zones can occur and result in massive fish kills.

The problem is not unique to this summer. Periodic hypoxia has been documented in this area since the 1980s, and increased nutrient pollution and its harmful effects are occurring globally.

To inform decision makers on possible solutions to these water quality challenges, WRI, the Global Environment and Technology Foundation, the Energy Research Centre of the Netherlands and the wider Global Partnership on Nutrient Management developed a Global Nutrient Management Toolbox of online resources at http://nutrientchallenge.org/toolbox2/gpnm-toolbox to support the sustainable management of nutrients


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