NEW YORK, New York — A recently published study by the Wildlife Conservation Society and others reveals that humpback whales on both sides of the southern Indian Ocean are singing different tunes, unusual since humpbacks in the same ocean basin usually all sing very similar songs.

A recent study has found humpback whales on both sides of the southern Indian Ocean are singing different tunes. credit S. Cerchio/WCS

The results of the study—conducted by researchers from WCS, Columbia University, and Australia —contradict previous humpback whale song comparisons. Generally, when song from populations in the same ocean basins are compared, researchers find that the songs contain similar parts or “themes.” The differences in song between the Indian Ocean humpback populations most likely indicate a limited exchange between the two regions and may shed new light on how whale culture spreads.

Read the full article at http://www.underwatertimes.com/news.php?article_id=10356201987

ScienceDaily (Jan. 26, 2012) — Over dinner on R.V. Calypso while anchored on the lee side of Glover’s Reef in Belize, Jacques Cousteau told Phil Dustan that he suspected humans were having a negative impact on coral reefs. Dustan — a young ocean ecologist who had worked in the lush coral reefs of the Caribbean and Sinai Peninsula — found this difficult to believe. It was December 1974.

But Cousteau was right. During the following three-plus decades, Dustan, an ocean ecologist and biology professor at the University of Charleston in South Carolina, has witnessed widespread coral reef degradation and bleaching from up close. In the late 1970s Dustan helped build a handheld spectrometer, a tool to measure light given off by the coral. Using his spectrometer, Dustan could look at light reflected and made by the different organisms that comprised the living reefs. Since then, he has watched reefs deteriorate at an alarming rate. Recently he has found that Landsat offers a way to evaluate these changes globally. Using an innovative way to map how coral reefs are changing over time, Dustan now can find ‘hotspots’ where conservation efforts should be focused to protect these delicate communities.

A Role for Remote Sensing

Situated in shallow clear water, most coral reefs are visible to satellites that use passive remote sensing to observe Earth’s surface. But coral reefs are complex ecosystems with coincident coral species, sand, and water all reflecting light. Dustan found that currently orbiting satellites do not offer the spatial or spectral resolution needed to distinguish between them and specifically classify coral reef composition. So instead of attempting to classify the inherently complex coral ecosystem to monitor their health, Dustan has instead started to look for change — how overall reflectance for a geographic location varies over time.

Dustan uses a time series of Landsat data to calculate something called temporal texture¬ — basically a map showing where change has occurred based on statistical analysis of reflectance information. While Dustan cannot diagnosis the type of change with temporal texture he can establish where serious changes have occurred. Coral communities have seasonal rhythms and periodicities, but larger, significant changes show up as statistical outliers in temporal texture maps and often correlate with reef decline.

A Case Study

Carysfort reef — named for the HMS Carysfort, an eighteenth century British warship that ran aground on the reef in 1770 — is considered the most ecologically diverse on the Florida Keys National Marine Sanctuary’s northern seaward edge, but today it is in a state of ecological collapse.

Dustan and colleagues conducted the first quantitative field study of coral health at Carysfort in 1974. After a quarter century their studies showed that coral had declined 92 percent. The coral had succumbed to an array of stressors culminating with deadly diseases.

Using the well-characterized Carysfort reef as his control, Dustan calculated the temporal texture for the reef using a series of 20 Landsat images collected between 1982 and 1996. The resulting temporal texture maps correlated with the known areas of significant coral loss (where coral communities have turned into algal-dominated substrates) and they correctly showed that the seaward shallow regions have had the most detrimental change.

This novel approach to change detection is only possible because the long-term calibration of Landsat data assures that data from year-to-year is consistent. Dustin needs at least 6 to 8 Landsat images to create a reliable temporal texture map, but the more data that is available, the finer the results.

Dustan tested this work in the U.S. because he had a robust study site and because prior to 1999 coverage of reefs outside of the U.S. was spotty. With the Landsat 7 launch in 1999 a new global data acquisition strategy was established and for the first time the planet’s coral reefs were systematically and regularly imaged, greatly increasing our knowledge of reefs. The Landsat archive enabled the completing of the first exhaustive global survey of reefs (Millennium Global Coral Reef Mapping Project, http://landsat.gsfc.nasa.gov/news/news-archive/news_0031.html). Efforts are currently underway to receive and ingest Landsat data collected and housed by international ground-receiving stations. International partners often downlink Landsat scenes of their countries that the U.S. does not, so it is very likely that historic reef images will be added the U.S. Landsat archive during this process.

Carrying on Outside of Carysfort

Temporal texture gives scientists an entirely new way to look at coral reefs. A worldwide study could help managers locate change ‘hotspots’ and could better inform conservation efforts.

Ideally, after more testing, Dustan would like to see an automatic change detection system implemented to follow major worldwide reef systems. “There is no reason that a form of temporal texture monitoring could not be implemented with current satellites in orbit,” Dustan says.

Because reefs are underwater it is difficult to grasp the extensive devastation being exacted upon them. Global temporal texture mapping could bring the ravages into focus.

The Landsat Program is a series of Earth observing satellite missions jointly managed by NASA and the U.S. Geological Survey. Landsat satellites have been consistently gathering data about our planet since 1972. They continue to improve and expand this unparalleled record of Earth’s changing landscapes for the benefit of all.

Story Source:

The above story is reprinted from materials provided by NASA/Goddard Space Flight Center.

Or rather, it is replaced.

A team led by USC microbiologist Katrina Edwards found that the microbes that thrive on hot fluid methane and sulfur spewed by active hydrothermal vents are supplanted, once the vents go cold, by microbes that feed on the solid iron and sulfur that make up the vents themselves.

Read the full article athttp://www.sciencedaily.com/releases/2012/01/120124184208.htm

The red-breasted Maori-wrasse, Cheilinus fasciatus. Like the butterflyfishes and damselfishes, wrasses have evolved in the presence of coral reefs. The close relationship between corals and fishes has stimulated the speciation of reef fishes and provided them with a sanctuary in difficult times. (Credit: João Paulo Krajewski)

The complex relationship we see today  between fishes and corals developed relatively recently in geological terms – and is a major factor in shielding reef species from extinction, says Professor David Bellwood of the ARC Centre of Excellence for Coral Reef Studies and James Cook University.

Read the full article at http://www.sciencedaily.com/releases/2012/01/120123094801.htm

Picture on left shows a trail of dying, white corals on the reef in March 2010. Picture on right shows the same area of the reef in May 2011 with barren rubble where the live corals once were. (Credit: Photos are courtesy of Greta Aeby, University of Hawaii – Manoa.)

ScienceDaily (Jan. 6, 2012) — In March 2010 an outbreak of a disease called acute Montipora White Syndrome (MWS) was discovered affecting coral reefs in Kaneohe Bay, Oahu. Follow-up surveys found that the disease left trails of rubble in its wake. It was estimated that over 100 colonies of rice coral (Montipora capitata) died during that initial outbreak. The disease has reappeared and is killing corals in Kaneohe Bay. The current outbreak has already affected 198 colonies and a rapid response team led by Dr. Greta Aeby (HIMB) has been activated to document the outbreak.

Members of the investigative team include scientists from the University of Hawaii, Hawaii Institute of Marine Biology (HIMB), and USGS National Wildlife Health Center. Members of the Eyes of the Reef Network (EOR), a program that trains community members to identify threats to Hawaii’s reefs, are also being asked to report on any signs of disease from other reefs.

Read the full article at http://www.sciencedaily.com/releases/2012/01/120106110700.htm

By Dwayne Meadows, NOAA

Scientists have found that human-caused carbon dioxide emissions, from the burning of fossil fuels in the last 100 to 200 years, have already raised ocean acidity far beyond the range of natural variations. Based on computer modeling and observations, they say these emissions, which increase water acidity by reacting with saltwater, may significantly reduce the calcification rate of marine organisms such as corals and mollusks. Read the full article at http://content.usatoday.com/communities/greenhouse/post/2012/01/greenhouse-gases-make-oceans-more-acidic-threaten-coral/1

Contact: Emily Howells
em.howells@gmail.com
61-747-534-203
ARC Centre of Excellence in Coral Reef Studies

Recent experiments conducted at the Australian Institute of Marine Science (AIMS) produced striking results, showing for the first time that corals hosting a single type of “zooxanthellae” can have different levels of thermal tolerance – a feature that was only known previously for corals with a mix of zooxanthellae.

Zooxanthellae are algal cells that live within the tissue of living coral and provide the coral host with energy; the relationship is crucial for the coral’s survival. Rising ocean temperatures can lead to the loss of zooxanthellae from the coral host, as a consequence the coral loses its tissue colour and its primary source of energy, a process known as ‘coral bleaching’. Globally, coral bleaching has led to significant loss of coral, and with rising ocean temperatures, poses a major threat to coral reefs.

It was previously known that corals hosting more than one type of zooxanthellae could better cope with temperature changes by favouring types of zooxanthellae that have greater thermal tolerance. However, until now it was not known if corals hosting a single type of zooxanthellae could have different levels of thermal tolerance.

Results recently published in the prestigious scientific journal, Nature Climate Change, showed corals that only host a single type of zooxanthellae may in fact differ in their thermal tolerance. This finding is important because many species of coral are dominated by a single type of zooxanthellae.

Read the full article at http://www.eurekalert.org/pub_releases/2012-01/acoe-mpn012012.php

Long-spined sea urchin (Diadema antillarum) may be a bioindicator

Florida Keys resident and marine biologist  Martin A. Moe, best known for his work with the long-spined sea urchin (Diadema antillarum), discusses the invisible pollution threatening our marine environment. In the Jan/Feb 2012 issue of CORAL Magazine.

Read the article courtesy of CORAL Magazine | www.coralmagazine-us.com

Digital Edition of that issue of CORAL (Coral Jan/Feb 2012, see pages 30-40). http://edition.pagesuite-professional.co.uk/Launch.aspx?EID=01987090-d3b9-40ca-9c62-559b8278318f

Proving that there are still plenty of places to explore and things to discover on Earth, the scientists made their finds over six continents (all except Antarctica) and three oceans (Atlantic, Pacific, and Indian), climbed to the tops of mountains and descended to the bottom of the sea, looked in their owns backyards (California) and on the other side of the world (Cameroon).

Their results, published in 33 different scientific papers, add to the record of life on Earth and help advance the Academy’s research into two of the most important scientific questions of our time: “How did life evolve?” and “How will it persist?”

Read the full article at http://www.sciencedaily.com/releases/2011/12/111215095613.htm