The article is in the journal Ecotoxicology. A link to the article can be
found at http://link.springer.com/article/10.1007/s10646-013-1161-y
Accepted: 7 December 2013
Abstract Benzophenone-2 (BP-2) is an additive to personal-care products and commercial solutions that protects against the damaging effects of ultraviolet light. BP-2 is an ‘‘emerging contaminant of concern’’ that is often released as a pollutant through municipal and boat/ship wastewater discharges and landfill leachates, as well as through residential septic
fields and unmanaged cesspits. AlthoughBP-2may be a contaminant on coral reefs, its environmental toxicity to reefs is unknown. This poses a potential management issue, since BP-2 is a known endocrine disruptor as well as a weak genotoxicant. We examined the effects of BP-2 on the larval form (planula) of the coral, Stylophora pistillata, as well as its toxicity to in vitro coral cells. BP-2 is a photo-toxicant; adverse effects are exacerbated in the light versus in darkness. Whether in darkness or light,
BP-2 induced coral planulae to transformfromamotile planktonic state to a deformed, sessile condition. Planulae exhibited an increasing rate of coral bleaching in response to increasing concentrations of BP-2. BP-2 is a genotoxicant to corals, exhibiting a strong positive relationship between DNA-AP lesions and increasing BP-2 concentrations. BP-2 exposure in the
light induced extensive necrosis in both the epidermis and gastrodermis. In contrast, BP-2 exposure in darkness induced autophagy and autophagic cell death. The LC50 of BP-2 in the light for an 8 and 24 h exposure was 120 and 165 parts per billion (ppb), respectively. The LC50s for BP-2 in darkness for the same time points were 144 and 548 ppb. Deformity EC20 levels (24
h) were 246 parts per trillion in the light and 9.6 ppb in darkness.
IMAGE: Diver Andrew Schantz of Florida International University studies the effect of pollution on corals in the Florida Keys.
Click here for more information.
CORVALLIS, Ore. – One of the largest and longest experiments ever done to test the impact of nutrient loading on coral reefs today confirmed what scientists have long suspected – that this type of pollution from sewage, agricultural practices or other sources can lead to coral disease and bleaching.
A three-year, controlled exposure of corals to elevated levels of nitrogen and phosphorus at a study site in the Florida Keys, done from 2009-12, showed that the prevalence of disease doubled and the amount of coral bleaching, an early sign of stress, more than tripled.
However, the study also found that once the injection of pollutants was stopped, the corals were able to recover in a surprisingly short time.
“We were shocked to see the rapid increase in disease and bleaching from a level of pollution that’s fairly common in areas affected by sewage discharge, or fertilizers from agricultural or urban use,” said Rebecca Vega-Thurber, an assistant professor in the College of Science at Oregon State University.
“But what was even more surprising is that corals were able to make a strong recovery within 10 months after the nutrient enrichment was stopped,” Vega-Thurber said. “The problems disappeared. This provides real evidence that not only can nutrient overload cause coral problems, but programs to reduce or eliminate this pollution should help restore coral health. This is actually very good news.”
The findings were published today in Global Change Biology, and offer a glimmer of hope for addressing at least some of the problems that have crippled coral reefs around the world. In the Caribbean Sea, more than 80 percent of the corals have disappeared in recent decades. These reefs, which host thousands of species of fish and other marine life, are a major component of biodiversity in the tropics.
IMAGE: This coral, which was part of a scientific study, is bleached as a result of exposure to elevated levels of nitrogen and phosphorus.
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Researchers have observed for years the decline in coral reef health where sewage outflows or use of fertilizers, in either urban or agricultural areas, have caused an increase in the loading of nutrients such as nitrogen and phosphorus. But until now almost no large, long-term experiments have actually been done to pin down the impact of nutrient overloads and separate them from other possible causes of coral reef decline.
This research examined the effect of nutrient pollution on more than 1,200 corals in study plots near Key Largo, Fla., for signs of coral disease and bleaching, and removed other factors such as water depth, salinity or temperature that have complicated some previous surveys. Following regular injections of nutrients at the study sites, levels of coral disease and bleaching surged.
One disease that was particularly common was “dark spot syndrome,” found on about 50 percent of diseased individual corals. But researchers also noted that within one year after nutrient injections were stopped at the study site, the level of dark spot syndrome had receded to the same level as control study plots in which no nutrients had been injected.
The exact mechanism by which nutrient overload can affect corals is still unproven, researchers say, although there are theories. The nutrients may add pathogens, may provide the nutrients needed for existing pathogens to grow, may be directly toxic to corals and make them more vulnerable to pathogens – or some combination of these factors.
“A combination of increased stress and a higher level of pathogens is probably the mechanism that affects coral health,” Vega-Thurber said. “What’s exciting about this research is the clear experimental evidence that stopping the pollution can lead to coral recovery. A lot of people have been hoping for some news like this.
“Some of the corals left in the world are actually among the species that are most hardy,” she said. “The others are already dead. We’re desperately trying to save what’s left, and cleaning up the water may be one mechanism that has the most promise.”
VIDEO: This is an interview with Rebecca Vega-Thurber about new findings in a coral reef study off the Florida Keys.
Click here for more information.
Nutrient overloads can increase disease prevalence or severity on many organisms, including plants, amphibians and fish. They’ve also long been suspected in coral reef problems, along with other factors such as temperature stress, reduced fish abundance, increasing human population, and other concerns.
However, unlike factors such as global warming or human population growth, nutrient loading is something that might be more easily addressed on at least a local basis, Vega-Thurber said. Improved sewage treatment or best-management practices to minimize fertilizer runoff from agricultural or urban use might offer practical approaches to mitigate some coral reef declines, she said.
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Collaborators on this research included Florida International University and the University of Florida. The work was supported by the National Science Foundation and Florida International University.
Editor’s Note: Digital images are available to illustrate this research:
Diver at study site: http://bit.ly/16bCW7w
Bleached coral: http://bit.ly/1bzLpjm
Nutrient dispenser: http://bit.ly/16gC8cp
A package of video interviews and associated B-roll, including underwater video, is also available for downloading in high resolution format:
Today the National Marine Fisheries Service published their 90-day finding
on a petition to list 23 coral species under the Endangered Species Act. The
23 corals are part of a wider set of 81 marine species the agency was
petitioned to list in July 2013. The finding determined that the available
information presents substantial scientific or commercial data or
information indicating that the petitioned action may be warranted for
three species (*Cantharellus noumeae, Siderastrea glynni*, and *Tubastraea
floreana*). We will initiate a status review of these species and we seek
information from interested parties and the public on the status, threats,
and conservation of these species. The public comment period opened today
and ends 24 December 2013. A 12-month finding on whether or not to propose
ESA listing for one or more of these three species is the next step in the
process.
We also determined that the petition did not present substantial
information indicating the petitioned actions may be warranted for the
remaining 20 species. These 20 species are: *Acropora roseni, Acropora
suharsonoi, Alveopora excelsa, Alveopora minuta, Ctenella chagius,
Hydnophora bonsai, Isopora togianensis, Lithophyllon ranjithi, Lobophyllia
serratus, Millepora boschmai, Millepora striata, Montipora setosa,
Parasimplastrea sheppardi, Pectinia maxima, Pocillopora fungiformis,
Porites desilveri, Porites eridani, Porites ornata, Rhizopsammia
wellingtoni, *and *Stylophora madagascarensis*. This ends the review
process for these 20 species.
The 90-day finding, petition, link to the online public comment site, and
other information are all available at:
http://www.nmfs.noaa.gov/pr/species/petition81.htm
best regards
Dwayne
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dwayne Meadows, Ph.D.
Species of Concern National Program Coordinator
Endangered Species Division
Office of Protected Resources (F/PR3)
National Marine Fisheries Service
1315 East West Highway
Silver Spring, MD 20910
(301) 427-8467
FAX: (301) 713-4060
Dwayne.Meadows@noaa.gov
http://www.nmfs.noaa.gov/pr/species/concern/
Hello all,
After the full moon in July, August, and September, researchers in 7 regions of the Caribbean (Mexico, Curacao, Belize, St. Thomas, Florida, Flower Gardens, Columbia) monitoring 9 coral species (A. cervicornis, A. palmata, A.. prolifera, Diploria/Pseudodiploria strigosa , Dendrogyra cylindrus, Montastraea/Orbicella franksi, M. annularis, M. faveolata, Montastraea cavernosa) for spawning activity. Overall it was a great year for Caribbean coral spawning.
For detailed information on location, spawning times, and environmental conditions, log into google docs and follow this link:
Please email me (nicole.fogarty@nova.edu) if you have any corrections or additional spawning observations. You can also join us on the “coral spawning research” facebook page for real time accounts of coral spawning events.
Nicole D. Fogarty, PhD
Assistant Professor
Nova Southeastern University
Oceanographic Center
8000 N. Ocean Drive
Dania Beach, FL 33004-3078
(954) 262-3630
Michael B. Morgan *, Terry W. Snell
Georgia Institute of Technology, School of Biology, Atlanta, GA 30332-0230, USA
Abstract
We characterize two genes expressed in Acropora cervicornis upon exposure to 0.5 lg/l of dibrom, a pesticide used for mosquito control in the Florida Keys. Fragments of these genes were isolated, sequenced, and developed into chemiluminescent probes for Northern slot blots. Expression of target transcripts was detected in corals exposed to a variety of stressors including organophosphates, organochlorines, heavy metals, naphthalene, and temperature. Within the context of stressors examined, the D25 probe demonstrates toxicant and concentration specificity for organophosphates, whereas the D50 probe had broader specificity, detecting transcripts in corals exposed to dibrom, naphthalene, and temperature stress. After characterizing specificity in the lab, these probes were used on field samples taken from the Florida Keys. Both probes detected their targets in samples taken from the upper Florida Keys in August 2000. Preliminary search of sequence databases suggest similarity exists between D25 and a thioesterase.
