Oregon State University: Large study shows pollution impact on coral reefs — and offers solution

Contact: Rebecca Vega-Thurber
Rebecca.vega-thurber@oregonstate.edu
541-737-1851

diver

IMAGE: Diver Andrew Schantz of Florida International University studies the effect of pollution on corals in the Florida Keys.
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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.

coral

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.
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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:

Underwater b-roll:

http://oregonstate.edu/dept/ncs/media/rebecca-vega-thurber-underwater-b-roll-news-release.mov

Package interview with Dr. Rebecca Vega Thurber:

http://oregonstate.edu/dept/ncs/media/rebecca-vega-thurber-package-news-release.mov

Dr. Rebecca Vega Thurber Interview:

http://oregonstate.edu/dept/ncs/media/rebecca-vega-thurber-interview-news-release.mov

Laboratory b-roll:

http://oregonstate.edu/dept/ncs/media/rebecca-vega-thurber-b-roll-news-release.mov

Rebecca Vega Thurber Interview (audio only):

Coral-List: Nova Southeastern University Report on Coral Spawning 2013

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:

https://docs.google.com/spreadsheet/ccc?key=0AuCz7WiTRAnkdGNpZ1k1VGwwb1NUYjdXR3BrQ0k3a1E&usp=sharing

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

Why I am Still Opposed to Widening and Deepening Key West Harbor to Accommodate Larger Cruise Ships by DeeVon Quirolo

Points to consider in the discussion of whether to vote for a feasibility study to widen and deepen Key West harbor:

The science has been indisputable for a long long time on the negative impacts of siltation and dredging on or near coral reefs. Corals are living permanent structures on the ocean bottom comprised of colonies of living polyps that need clear, clean nutrient free waters to thrive. Dredging creates fine sediment and silt that covers corals, preventing photosynthesis and resulting in massive mortality, especially for Elkhorn and Staghorn corals–which cannot slough it off as can other corals. Such sedimentation also reduces the ability of all marinelife, including tarpon and other fish that utilize this area for habitat, to survive.

Episodic storm activity may stir up sediment but the wave action of those storms can also remove loose particulate matter from areas of the ocean bottom. While storm activities have historically affected visibility in the harbor and at the reefs, they do not compare in scale to the massive, chronic, intense effects of outright removal of habitat and the smothering of living formations by tons of dredge sediments that would occur immediately in the harbor and at nearby downstream coral reefs if additional widening and deepening of Key West Harbor were to occur.

It is incredulous to me that anyone associated with protecting coral reefs would dispute this elementary fact of coral ecology. In addition, the health of sea grasses and myriad other marinelife that depend upon this habitat would be severely impacted, including endangered sea turtles and dolphins.

The Key West Harbor Reconnaisance Report published November 2010 noted that the harbor is included in the “critical essential habitat” for both Elkhorn and Staghorn corals under the Endangered Species Listing for them. There has not been one case of allowing removal of critical essential habitat from the Jacksonville Corps of Engineers office in the last 15 years.

It states: “Under the Endangered Species Act (ESA) of 1973; the threatened coral Acropora cervicornis (staghorn coral) and Acropora palmata (elkhorn coral) could be located adjacent to the channel in the areas proposed for expansion as this area is designated as critical habitat for these species. While it is possible to relocate the actual colonies of coral, the critical habitat would be permanently removed. It is highly likely that the removal of several acres of occupied designated critical habitat (habitat where the species has been shown to be able to flourish under baseline conditions) could be considered an adverse modification of critical habitat under Section 7 of the ESA. This would be Jacksonville District’s first adverse modification of critical habitat determination in the last 15 years. It is also unknown what reasonable and prudent alternatives and measures National Marine Fisheries Service (NMFS) would include in a biological opinion to avoid the project adversely modifying designated critical habitat, as required under Section 7 of the Act.* It is expected that resource agencies would oppose any channel modifications outside the existing footprint.”

So this whole feasibility study could be a huge waste of money because there are good reasons why a permit would never be issued for the project thereafter. Surely we can find a more sustainable use of $5 million dollars—how about some stormwater treatment for the island of Key West to improve water quality?

The feasibility study is an effort to calculate the possibility of further widening and dredging in a harbor that was deepened just five years ago. Underneath Key West lies a fresh water aquifer. There are upwellings of fresh water in the harbor today. A massive deepening and widening may have severe unintended consequences on the aquifer, that at a minimum could result in salt water intrusion of that fresh water lens.

The last harbor dredging project just a few years ago included a mitigation plan by the Florida Keys National Marine Sanctuary to remove corals from the harbor with the purpose of restoring the damage. Despite their best efforts, there have been only a few of those corals planted in an offshore boat grounding site. For the most part, there has been no successful effort to restore the extent of coral colonies that existed in this area prior to the last dredging. It is therefore highly unlikely that another dredging project will succeed in restoring the habitat removed via mitigation this time either. It is just a false hope that the loss of biodiversity will be anything but an ecological disaster for this otherwise already stressed part of Key West’s coral reef ecosystem.

Often these dredge projects result in in-filling thereafter due to storm activity. Key West may be saddled with a harbor that produces chronic sedimentation without regular repeated environmentally destructive maintenance dredging. This will in turn affect the downstream coral reefs with additional chronic smothering contaminated sediment.

The greater question really is: How much more can the surrounding coral reef ecosystem of the Florida Keys handle in terms of human impacts? Isn’t it enough to have a thriving hotel, tourism and real estate industry? Can’t we draw a line in the sand and say “enough is enough”? Already the hoards of cruise ship visitors denigrates the downtown section to the exclusive benefit of a few businesses while high-end resorts and guesthouses hold their breath that this low-end massive impact to our quality of life will not repel their key markets. What about those who still hope that Key West can be a magic island home–don’t they deserve consideration?

Craig and I would encourage every voter in Key West to vote NO on the feasibility study to dredge Key West harbor….. again.

DeeVon Quirolo

Key West Harbor Reconnaissance Report by US Army Corp of Engineers

key_west_harbor_excerpt

Perhaps most importantly, this brief 7-page report ends with the following: DV

Under the Endangered Species Act (ESA) of 1973; the threatened coral Acropora cervicornis (staghorn coral) and Acropora palmata (elkhorn coral) could be located adjacent to the channel in the areas proposed for expansion (Figure 2) as this area is designated as critical habitat for these species. While it is possible to relocate the actual colonies of coral, the critical habitat would be permanently removed. It is highly likely that the removal of several acres of occupied designated critical habitat (habitat where the species has been shown to be able to flourish under baseline conditions) could be considered an adverse modification of critical habitat under Section 7 of the ESA. This would be Jacksonville District’s first adverse modification of critical habitat determination in the last 15 years. It is also unknown what reasonable and prudent alternatives and measures National Marine Fisheries Service (NMFS) would include in a biological opinion to avoid the project adversely modifying designated critical habitat, as required under Section 7 of the Act. It is expected that resource agencies would oppose any channel modifications outside the existing footprint.

Academia.Edu: Dredging and shipping impacts on southeast Florida coral reefs by Brian K. Walker, et. al.

http://academia.edu/1258184/Dredging_and_shipping_impacts_on_southeast_Florida_coral_reefs
Proceedings of the 12th International Coral Reef Symposium, Cairns, Australia, 9-13 July 201219A Human impacts on coral reefs: general session

Authors: Brian K. Walker 1, David S. Gilliam 1, Richard E. Dodge 1, Joanna Walczak²
1 National Coral Reef Institute, Nova Southeastern University, Dania Beach, FL, USA
² Florida Department of Environmental Protection, Miami, FL, USA
Corresponding author: walkerb@nova.edu

Abstract.
Many coastal regions have experienced extensive population growth during the last century. Commonly, this growth has led to port development and expansion as well as increased vessel activity which can have detrimental effects on coral reef ecosystems. In southeast Florida, three major ports built in the late 1920’s along 112 km of coastline occur in close proximity to a shallow coral reef ecosystem. Recent habitat mapping data were analyzed in GIS to quantify the type and area of coral reef habitats impacted by port and shipping activities. Impact areas were adjusted by impact severity: 100% of dredge and burial areas, 75% of grounding and anchoring areas, and 15% of areas in present anchorage. Estimates of recent local stony coral density and cover data were used to quantify affected corals and live cover. After adjusting for impact severity,312.5 hectares (ha) of impacted coral reef habitats were identified. Burial by dredge material accounted for 175.8 ha. Dredging of port inlet channels accounted for 84.5 ha of reef removal. And 47.6 ha were impacted from a large ship anchorage. Although the full extent of all ship groundings and anchor drags associated with the ports is unknown, the measured extents of these events totaled 6 ha. Based on the adjusted impact areas,over 8.1 million corals covering over 11.7 ha of live cover were impacted. Burial impacts were the greatest. The planned expansion of two of the ports would remove an additional approximate 9.95 ha of coral reef habitat.Ongoing marine spatial planning efforts are evaluating the placement of large ship anchorages in an effort reduce future impacts from ship anchoring. However, increasing populations and shipping needs will likely continue to be prioritized over protection of these valuable natural resources.

Full text and tables at:
Walker_et_al_ICRS2012_Proceedings_SEFL_Shipping_Impacts_Revision

NOAA: National Marine Sanctuaries Program: Florida Keys 2011 Condition Report

http://sanctuaries.noaa.gov/science/condition/fknms/welcome.html

This report is best viewed by going to the link above. Below are a few key reports–I added the bold sections which I find the most disturbing.
DV

Florida Keys National Marine Sanctuary
Condition Summary Table

WATER
1. Are specific or multiple stressors, including changing oceanographic and atmospheric conditions, affecting water quality and how are they changing?

Conditions appear to be declining
Large-scale changes in flushing dynamics over many decades have altered many aspects of water quality; nearshore problems related to runoff and other watershed stressors; localized problems related to infrastructure. Selected conditions may inhibit the development of assemblages and may cause measurable but not severe declines in living resources and habitats. In conjunction with the Environmental Protection Agency and Florida Department of Environmental Protection, the sanctuary will continue implementation of its Water Quality Protection Program and conduct long-term water quality monitoring and research to understand the effects of water transported from near-field and far-field sources, including Florida Bay on water quality in the sanctuary. New regulations prohibit discharge or deposit of sewage from marine sanitation devices (MSD) within the boundaries of the sanctuary and require MSDs be locked to prevent sewage discharge or deposit while inside sanctuary boundaries. The marine area surrounding the Florida Keys has been designated as a Particularly Sensitive Sea Area by the International Maritime Organization. Florida Department of Health Florida Healthy Beaches Program tests for the presence of fecal coliform and enterococci bacteria in beach water on a weekly basis, at 17 locations throughout the Keys. The MEERA Project, which is designed to provide early detection and assessment of biological events occurring in the Florida Keys and surrounding waters, continues to be supported by the sanctuary. A well-established law enforcement program is in place, including NOAA Fisheries Service, Florida Fish and Wildlife Conservation Commission, and U.S. Coast Guard.

2. What is the eutrophic condition of sanctuary waters and how is it changing?
Conditions do not appear to be changing
Long-term increase in inputs from land; large, persistent phytoplankton bloom events, many of which originate outside the sanctuary but enter and injure sanctuary resources. Selected conditions have caused or are likely to cause severe declines in some but not all living resources and habitats.

3. Do sanctuary waters pose risks to human health and how are they changing?
Conditions do not appear to be changing
Rating is a general assessment of “all waters” of the sanctuary, knowing that in very specific locations, the rating could be as low as “poor.” Increased frequency of HABs and periodic swim advisories. Selected conditions have resulted in isolated human impacts, but evidence does not justify widespread or persistent concern.

4. What are the levels of human activities that may influence water quality and how are they changing?
conditions appear to be improving
Historically, destructive activities have been widespread throughout the Florida Keys, but many recent management actions are intended to reduce threats to water quality. Selected activities have caused or are likely to cause severe impacts, and cases to date suggest a pervasive problem.

HABITAT
5. What are the abundance and distribution of major habitat types and how are they changing?
Conditions do not appear to be changing
In general, mangrove and benthic habitats are still present and their distribution is unchanged, with the exception of the mangrove community, which is about half of what it was historically. The addition of causeways has changed the distribution of nearshore benthic habitats in their vicinity. Selected habitat loss or alteration has taken place, precluding full development of living resource assemblages, but it is unlikely to cause substantial or persistent degradation in living resources or water quality. Marine zoning is used in the sanctuary to protect sensitive habitats like shallow coral reefs. Mooring buoys have been installed as a threat-reduction measure. Sanctuary staff and volunteers educate and inform boaters about the unique nature of the coral reef habitat, and organize shoreline clean-up and marine debris removal efforts. Sanctuary staff assess and restore vessel grounding injuries to seagrass and coral habitats, as well as perform coral rescue activities associated with coastal construction. Large vessel avoidance and Racon beacons in lighthouses have resulted in declines in large vessel groundings. An Area To Be Avoided was established to prevent ships larger than 50 meters in overall length from transiting through sensitive areas in the sanctuary. A well established permitting program is in place to issue a variety of permits for activities that are otherwise prohibited by sanctuary regulations. There is also a well-established law enforcement program in place, including NOAA Fisheries Service, the Florida Fish and Wildlife Conservation Commission, and the U.S. Coast Guard. State of Florida’s Mangrove Trimming and Preservation Act of 1996 (§403.9321-403.9333) regulates how mangroves can be trimmed and altered, and by whom.

6. What is the condition of biologically structured habitats and how is it changing?
conditions appear to be declining
Loss of shallow (<10 meters) Acropora and Montastraea corals has dramatically changed shallow habitats; regional declines in coral cover since the 1970s have led to changes in coral-algal abundance patterns in most habitats; destruction of seagrass by propeller scarring; vessel grounding impacts on benthic environment; alteration of hard-bottom habitat by illegal casitas. Selected habitat loss or alteration has caused or is likely to cause severe declines in some but not all living resources or water quality.

7. What are the contaminant concentrations in sanctuary habitats and how are they changing?
?
Few studies, but no synthesis of information.
N/A

8. What are the levels of human activities that may influence habitat quality and how are they changing?
conditions appear to be declining
Coastal development, highway construction, vessel groundings, over-fishing, shoreline hardening, marine debris (including derelict fishing gear), treasure salvaging, increasing number of private boats, and consequences of long-term changes in land cover on nearshore habitats. Selected activities have caused or are likely to cause severe impacts, and causes to date suggest a pervasive problem.

LIVING RESOURCES
9. What is the status of biodiversity and how is it changing?
conditions appear to be declining
Relative abundance across a spectrum of species has been substantially altered, with the most significant being large reef-building corals, large-bodied fish, sea turtles, and many invertebrates, including, the long-spined sea urchin. Recovery is questionable. Selected biodiversity loss has caused or is likely to cause severe declines in some but not all ecosystem components and reduce ecosystem integrity. Marine zoning assists in the protection of the biological diversity of the marine environment in the Keys. Mooring buoys have been installed in these zones to reduce anchor damage to coral reef biota. The sanctuary’s education and outreach team established the “Blue Star” program to help reduce the impact of divers and snorkelers on the coral reef ecosystem. NOAA has also established the Dolphin SMART program encouraging responsible viewing of wild dolphins. Sanctuary staff assesses and restores vessel grounding injuries to seagrass and coral habitats, as well as performs coral rescue activities associated with coastal construction. NOAA Fisheries Service (American Recovery and Reinvestment Act) awarded $3.3 million to support Acropora coral recovery and restoration in Florida (including the Keys) and the U.S. Virgin Islands. Other coral nursery efforts are also underway that contribute to coral restoration. Private efforts examining potential of long-spined sea urchin recovery via nursery propagation and rearing are also underway. A well-established permitting program is in place to issue a variety of permits for activities that are otherwise prohibited by sanctuary regulations, including removal of the invasive lionfish from the small no-take zones. The Florida Keys “Bleach Watch” Program utilizes volunteers to provide reports from the reef on the actual condition of corals throughout the bleaching season. The sanctuary also participates in oil spill drills sponsored by the U.S. Coast Guard and is a partner in the Florida Reef Resilience Program. There is a well-established law enforcement program in place.

10. What is the status of environmentally sustainable fishing and how is it changing?
?
Historical effects of recreational and commercial fishing and collection of both targeted and non-targeted species; it is too early to determine ecosystem effects of new fishery regulations and new ecosystem approaches to fishery management. Extraction has caused or is likely to cause severe declines in some but not all ecosystem components and reduce ecosystem integrity.

11. What is the status of non-indigenous species and how is it changing?
conditions appear to be declining
Several species are known to exist; lionfish have already invaded and will likely cause ecosystem level impacts; impacts of other non-indigenous species have not been studied. Non-indigenous species may inhibit full community development and function, and may cause measurable but not severe degradation of ecosystem integrity.

12. What is the status of key species and how is it changing?
Conditions do not appear to be changing
Reduced abundance of selected key species including corals (many species), queen conch, long-spined sea urchin, groupers and sea turtles. The reduced abundance of selected keystone species has caused or is likely to cause severe declines in ecosystem integrity; or selected key species are at severely reduced levels, and recovery is unlikely.

13. What is the condition or health of key species and how is it changing?
conditions appear to be declining
Hard coral and gorgonian diseases and bleaching frequency and severity have caused substantial declines over the last two decades; long-term changes in seagrass condition; disease in sea turtles; sponge die- offs; low reproduction in queen conch; cyanobacterial blooms; lost fishing gear and other marine debris impacts on marine life. The comparatively poor condition of selected key resources makes prospects for recovery uncertain.

14. What are the levels of human activities that may influence living resource quality and how are they changing?
Conditions do not appear to be changing
Despite the human population decrease and overall reduction in fishing in the Florida Keys since the 1990s, heavy recreational and commercial fishing pressure continues to suppress biodiversity. Vessel groundings occur regularly within the sanctuary. Annual mean number of reported petroleum and chemical spills were around 150 during that time period, with diesel fuel, motor oil, and gasoline representing 49% of these incidents collectively. Over the long term, localized direct impacts may be overwhelmed by the adverse and wide-ranging indirect effects of anthropogenic climate change resulting in sea level rise, abnormal air and water temperatures, and changing ocean chemistry. Selected activities have caused or are likely to cause severe impacts, and cases to date suggest a pervasive problem.