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Archive for November, 2013

StingrayCAM

Like Mother, Like Son: Stingrays Pass Toxic Pollutants on to Their Offspring

Animals in early stages of development are particularly susceptible to harmful effects of toxic pollutants. For this reason, the transfer of toxic pollutants from mothers to their young has been the subject of intense research. In this study, researchers from California State investigated how non-mammalian species like sharks, skates, and rays pass toxic pollutants on to their young.

Figure 1. Pyramid construction of the artificial reefs.

How Our “Trash” Can Aid Juvenile Red Snappers

Cement, limestone, and even old barges are being used in the northern Gulf of Mexico to build additional habitats for several fish species. These recycled, man-made structures, also known as artificial reefs, have been piling up off the coast of the U.S. for the last 50-some years. While these rubble piles may look random, time and energy has gone into figuring out what the best design is to help aid fish species in terms of habitat safety.

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Is the Oil Sands Industry in Canada Linked to Mercury Levels in Birds?

The oil or “tar” sands in Alberta, Canada are the third largest known reserves of accessible oil in the world. They are located around 200 km upstream of the Peace-Athabasca Delta, which is considered a wetland of international significance. This Delta is an ecologically sensitive habitat that provides services for millions of birds, which led a group of scientists in Canada to study mercury levels in bird eggs and investigate sources of mercury to the area.

Carbon on Fire! The role dissolved black carbon plays in the ocean

Fire-derived carbon (or black carbon) composes at least 10% of the marine dissolved organic carbon pool and may act accelerate the degradation of dissolved organic carbon back into carbon dioxide.

Neosiphonia harveyi

Growing Like a Seaweed: How ocean acidification is aiding the growth and expansion of macroalgae.

While calcifying organisms like corals and bivalves are projected to struggle under future levels of carbon dioxide (CO2), non-calcifying seaweeds that use CO2 for photosynthesis are going to exhibit normal, or increased, growth and productivity. Here, researchers show that increases in CO2 result in faster growth rates and increased photosynthetic activity in the invasive red alga, Neosiphonia harveyi. Researchers also tested temperature as an environmental factor and found a greater increase in growth and productivity in algae treated with colder water relative to warmer water. This finding is significant as low temperatures typically limit the growth of an individual alga and limit the range of algal species. Could CO2 increase the geographic range and success of seaweed invasions?

Turbidity current - dense currents of sediment mixed with water.

From the beach to the abyss: A sand grain’s journey at La Réunion Island

The path a grain of sand takes from land to the deep sea is largely made possible by turbidity currents- dense currents of sediment and water traveling rapidly through the ocean. A recent study focused on La Réunion Island, a volcanic island in the Indian Ocean, highlights the importance of submarine canyons and turbidity currents in shaping the offshore geology.

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Perfluorooctanoic acid (PFOA) Entering Deeper Ocean via Vertical Eddy Diffusion

The ocean is home to many creatures: plankton, fish, mammals, etc. But it is also ‘home’ to a number of persistent organic pollutants (POPs), which are usually at low concentrations in the water but have the potential to bioaccumulate. Where do these pollutants end up? Do they stay in the surface water or do they sink into the deep?

http://upload.wikimedia.org/wikipedia/commons/6/65/Fishing_Trawler.jpg

Cooked fish: Ocean warming and global fisheries

Global fisheries are expected to change as ocean temperatures warm. A recent study by Cheung et al. uses mean temperature of catch, a metric based on species’ average thermal preferences, to determine whether fisheries are changing to include more warm-water species.

Bamboo mattresses with test substrates were placed in coastal areas were there are already naturally established oyster beds.

Aquaculture as a means of food and protection?

The low lying coast of Bangladesh is burdened with natural weather patterns that bring storm surges, heavy rainfall, and intense flooding. As sea level rises and greater coastal erosion is predicted, long term solutions to maintaining low lying areas must be investigated. Researchers at the Institute of Marine Science and Fisheries in Bangladesh, in collaboration with other institutes, studied the success of oyster aquaculture in reducing erosion and improving local fisheries. This is their story….

Anthropogenic marine debris (Source: http://www.oprah.com/world/Ocean-Pollution-Fabien-Cousteaus-Warning-to-the-World/1)

Waiter, there’s a whale in my soup: investigating the South Pacific garbage patch

Plastic debris has been found in both the North Pacific and North Atlantic since the early 1970s. It accumulates in naturally forming gyres located in the subtropical zones of the world’s oceans, creating a “plastic soup.” Recent investigations have confirmed the presence of a similar garbage patch in the South Pacific.

Figure1.Calculated surface water pH changes arising from shipping-derived inputs of SOx and NOx. Calculations begin with the month of January.

Emissions from International Shipping Vessels Contribute to Ocean Acidification

Ship emissions of sulfur and nitrogen oxides (SOx, NOx) can be deposited and form sulfuric and nitric acid in surface water. Do heavily-trafficked trade routes result in “hotspots” of ocean acidification? Hassellöv and her team show “hotspots” that coincide with areas of heavy shipping traffic and seasonal stratification.

Gavia immer is the scientific name for the common loon, a top predator and a prominent symbol of the northern wilderness. Picture by Bob Weaver.

Top predators reveal the extent of mercury pollution in Canadian waters

Common loons, walleye, northern pike, and yellow perch play integral roles in ecosystem dynamics and environmental policy decisions. In this research project, they act as useful indicators to determine dangerously toxic levels of methylmercury in Canada.

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