Cup corals (Desmophyllum) grow around an anemone on a mud-covered ledge. During the Deepwater Canyons 2013 expedition, scientists collected cup coral specimens to help them understand the factors that influence the distribution of this species and perhaps even solve the mystery of differences observed between the deep and shallow populations.
Learn more: http://oceanexplorer.noaa.gov/explorations/13midatlantic/logs/may17/may17.html
Showing posts tagged coral
The monkeylike face of a goby fish peers out from the center of a coral labyrinth. The fish depends on the coral for its home, and, in turn, often cleans smothering algae from the coral. This image was accepted into the Art of Science 2013 competition at Princeton University.
Photo: Chhaya Werner, Princeton Univ. Art of Science Competition
(via: Live Science)
What is coral bleaching?
Coral bleaching is a serious problem facing corals all over the world. It is a general stress response of corals, and is the result of several different factors, especially increasing sea temperature. This causes the zooxanthellae, or symbiotic algae that live with the coral, to be expelled. The coral becomes white or “bleached”, and is unable to obtain the nutrients it needs, as it relies on its photosynthetic zooxanthellae.
Increasing sea temperatures are the cause of mass bleaching, but the following threats are responsible for small-scale bleaching:
- Decline in zooplankton, causing starvation.
- Ocean acidification.
- Bacterial infections.
- Changes in ocean salinity.
The most severely affected coral reefs include the Great Barrier Reef, reefs in the Indian Ocean, around the Maldives, Seychelles, and Hawaii. Up to 90% of corals have been lost from these locations.
A huge range of sea life depends on coral reefs for survival, so the disappearance of the corals would have a dire effect on the oceans. In turn, this would impact on many people who rely on the sea for their food and livelihoods.
Photo: John Pascal.
Endangered Ocean Creatures Beyond the Cute and Cuddly
by Emily Frost
Our oceans are taking a beating from overfishing, pollution, acidification and warming, putting at risk the many creatures who make their home in seawater. But when most people think of struggling ocean species, the first animals that come to mind are probably whales, seals or sea turtles.
Sure, many of these large (and adorable) animals play an important part in the marine ecosystem and are threatened with extinction due to human activities, but in fact, of the 94 marine species listed under the Endangered Species Act (ESA), only 45 are marine mammals and sea turtles. As such, these don’t paint the whole picture of what happens under the sea. What about the remaining 49 that form a myriad of other important parts of the underwater web?
These less charismatic members of the list include corals, sea birds, mollusks and, of course, fish. They fall under two categories: endangered or threatened. According to NOAA’s National Marine Fisheries Service (pdf), one of the groups responsible for implementing the ESA, a species is considered endangered if it faces imminent extinction, and and a species is considered threatened if it is likely to become endangered in the future. A cross section of these less-known members of the ESA’s list are described in detail here…
(read more: Smithsonian Magazine)
(photos: T - Atlantic Salmon by E. Peter Steenstra/USFWS; ML - Short-tailed albatross by USFWS; MR - White abalone by John Butler, NOAA; B - Staghorn Coral by Albert Kok)
Deep under the sea surface lie “coral gardens” that rival flower gardens in terms of color and beauty. Scientists are studying the octocorals that make up these gardens to understand how long they live and how they reproduce, to ultimately help us understand and better protect these complex ecosystems…
Learn more: http://oceanexplorer.noaa.gov/explorations/13midatlantic/logs/may11/may11.html
Images courtesy of Deepwater Canyons 2013 - Pathways to the Abyss, NOAA-OER/BOEM/USGS.
Deep Sea Coral and Symbiotic Bacteria
Just like us, corals have bacteria that live in them and on them. These bacteria are a natural part of the coral’s biology (just like the bacteria in our guts) and are necessary for the health of the coral. However, we are still in the early stages of understanding which bacteria are present and what they are doing for the corals.
During the Deepwater Canyons 2013 expedition, scientists are collecting coral samples to help them understand which is more important in shaping the coral-associated bacterial community: host or habitat?
(Learn more: NOAA Ocean Explorer)
The Deepwater Canyons 2013: Pathways to the Abyss expedition is underway!
We’ll be posting logs from the field soon, but in the interim, do you have a question you’d like to ask one of the explorers? If so, check out our “Ask an Explorer” page and then fire away:
http://oceanexplorer.noaa.gov/explorations/13midatlantic/logs/ask/ask.html.
About the image: Closeup view of Paragorgia arborea (bubblegum coral) encountered during last year’s expedition.
Source: http://oceanexplorer.noaa.gov/explorations/12midatlantic/logs/sep7/media/coralcloseup.html.
(via: NOAA)
Help Save the World’s Best Marine Reserve: Cabo Pulmo
Established in 1995, Mexico’s Cabo Pulmo Marine National Park is slightly more than 7,000 hectares of coastal waters in the Gulf of California, offshore from the small village of Cabo Pulmo. The park’s establishment followed a period of determined lobbying by the village’s 100 or so residents, who had become alarmed at overfishing and declines in the area’s marine life. The reserve is no more than 5 kilometers (3 miles) wide and measures just 14 kilometers (almost 9 miles) north to south. And yet its impact on the marine life within it, such as these Devil Rays, has been profound – so much so that researchers have dubbed it “the most successful marine reserve in the world.”…
(read more: http://news.discovery.com/animals/endangered-species/most-successful-marine-reserve-cabo-pulmo-110812.htm)
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What Can You Do to Help?
You can help save one of the oldest living coral reefs in the world with a click of your mouse: http://bit.ly/178KBhG
For 20,000 years, the reef of Cabo Pulmo has provided sanctuary for whale sharks, Pacific manta rays, humpback whales, dolphins and sea turtles, but today this marine reserve and the thriving sea that surrounds it is still under threat from overdevelopment.
Urge North America’s environmental authorities to support strong enforcement and protect the coral reef. Send your message!
http://bit.ly/178KBhG
(Photo courtesy of of Octavio Aburto / iLCP)
Mushroom Coral (Ctenactis albitentaculata), Lembeh Strait, Sulawesi, Indonesia
(photo: Bernard Dupont)
Black-sided Hawkfish (Paracirrhites forsteri) in Acropora grandis coral, East Timor.
(photo: Nick Hobgood)
A team of scientists from the Catlin Seaview Survey has discovered reef coral living at 125 m, the deepest ever found on the Great Barrier Reef. The remarkable find of a community of reef corals was made on the outer edge of the Ribbon Reefs off the north of the Barrier Reef. The extreme depth is more than four times the depth of the shallow reef coral habitat (0-30m) which scuba divers can access.
(via:Guardian UK) (Photo: Catlin Seaview Survey Expedition)
It’s not easy to count and record every single species you see while on a scientific dive.
To make it easier (and easier to verify after the fact), researchers on an expedition with the Khaled bin Sultan Living Oceans Foundation are taking photo transects of reefs around the world:
Each photo they take covers one square meter of reef. Using these photos, in combination with various computer programs, we can calculate the percentage of each organism on the bottom, the different sizes of corals or even the total area covered by coral. Photo transects are just another tool we have to help us describe and evaluate these reefs.
Another standard tool used on coral reefs are ARMS, which act like mini-condominiums for tiny animals living on reefs! A better way to measure marine life, ARMS allow researchers to compare coral animal diversity from reefs around the world.
Photos: 1) Brian Beck; 2) Ken Marks
The World's 10 Most Amazing Coral Reefs (PHOTOS)
(via: The Weather Channel)
Carnation Corals (Dendronephthya)
Strikingly beautiful carnation corals in the genus Dendronephthya are among the most commonly traded soft corals. However, these corals are poor choices for aquarium hobbyists. Since they lack algal symbionts (zooxanthellae), they must extract all of their food from the water. But getting the right balance of nutrients is difficult in an aquarium, so most captive Dendronephthya die within a few weeks.
This spectacular specimen, hanging out with an egg cowrie snail, was photographed in the wild in North Sulawesi by Bernard Dupont. It comes to EOL via Flickr (cc-by-nc-sa): http://www.flickr.com/photos/berniedup/7970532646/
More about these corals: http://eol.org/pages/41372
Ocean Acidification
Ocean acidification will literally dissolve some of the shells in the ocean. In this video, Scientists discuss the impact of the ocean’s changing pH levels.
Learn more by visiting our website:
