coral, coral reefs, dredging, reef health

Science Network: Offshore dredging severely impacts coral reefs

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http://www.sciencewa.net.au/topics/fisheries-a-water/item/1684-offshore-dredging-severely-impacts-coral-reefs.html
Thursday, 13 September 2012 06:00

Murky coral
The study found that sediment accumulation on coral tissue was a “strong and consistent cause of tissue mortality” and resulted in the death of whole coral fragments over prolonged periods.

Murky_coral

Image: Dan Derret RESEARCH by the Australian Institute of Marine Science has discovered that proposed dredging works along the WA coast could severely impact certain coral species found in local waters.

Scientists from the Institute along with the Australian Research Centre of Excellence conducted laboratory tests to develop lethal and sub-lethal benchmarks for coral exposed to dredging-generated sediments related to offshore developments.

The researchers tested two species of coral found in offshore locations to six levels of total suspended solids for 16 weeks, including a four week recovery period.

They tested the horizontal foliaceous species Montipora Aequituberculata and the upright branching species Acropora Millepora, both of which are found along WA’s coast.

Montipora Aequituberculata proved to be more susceptible as after 12 weeks all coral tissue under the sediment had died, exposing white coral skeleton.

Australian Institute of Marine Science senior principal research scientist Ross Jones says the sediment can affect coral by impacting their ability to feed as well as settling on the coral’s surface, causing it to expend energy cleaning itself.

“It can also attenuate light—light attenuation is a key thing because a lot of these habitats are primary producer habitats so the corals and sea life need light to photosynthesise and light is attenuated by the sediments,” Dr Jones says.

“It is like having permanently cloudy weather all the time, so it has the potential to have an effect on the marine environment.”

The study found that sediment accumulation on coral tissue was a “strong and consistent cause of tissue mortality” and resulted in the death of whole coral fragments over prolonged periods.

“What the study showed was that one species which was generally a flat plate-like coral was affected more so that the branching Acropora species because the sediment began to pile up on the coral,” Dr Jones says.

“That happened to an extent and rate at which it couldn’t clear itself, so it gradually became buried because the sedimentation rate was faster than its ability to clear itself.”

Woodside Energy funded the study and was cited as the operator of the proposed $30 billion Browse liquefied natural gas development at James Price Point, north of Broome.

Dr Jones says Woodside commissioned the study because it was investigating the effects of dredging at Browse.

“This study was initially commissioned by Woodside to try and come up with some numbers to build an environmental assessment of the project,” Dr Jones says.

He says this report is only a small amount of the research that will be conducted in the next few years into what sediment does to corals and other marine life in response to the proposed dredging.

coral, coral reefs, cruise ships, dredging, Florida Keys National Marine Sanctuary, Florida Keys reefs, reef health

Key West Harbor Reconnaissance Report by US Army Corp of Engineers

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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.

coral, coral reefs, dredging, Florida Keys National Marine Sanctuary, Florida Keys reefs, reef health

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

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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

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Increased Stray Gas Abundance in a Subset of Drinking Water Wells Near Marcellas Shale Gas Extraction

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StrayGasStudy

Robert B. Jacksona,b,1, Avner Vengosha, Thomas H. Darraha, Nathaniel R. Warnera, Adrian Downa,b, Robert J. Poredac,
Stephen G. Osbornd, Kaiguang Zhaoa,b, and Jonathan D. Karra,b
aDivision of Earth and Ocean Sciences, Nicholas School of the Environment and
bCenter on Global Change, Duke University, Durham, NC 27708;
cDepartment of Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627; and
dGeological Sciences Department, California State Polytechnic University, Pomona, CA 91768

Edited by Susan E. Trumbore, Max Planck Institute for Biogeochemistry, Jena, Germany, and approved June 3, 2013 (received for review December 17, 2012)

Horizontal drilling and hydraulic fracturing are transforming energy production, but their potential environmental effects remain controversial. We analyzed 141 drinking waterwells across the Appalachian Plateaus physiographic province of northeastern Pennsylvania, examining natural gas concentrations and isotopic signatures with proximity to shale gas wells. Methane was detected in 82% of drinking water samples, with average concentrations six times higher for homes <1 km from natural gas wells (P = 0.0006). Ethane was 23 times higher in homes <1 km from gas wells (P =0.0013); propane was detected in 10 water wells, all within approximately 1 km distance (P = 0.01). Of three factors previously proposed to influence gas concentrations in shallow groundwater (distances to gas wells, valley bottoms, and the Appalachian Structural Front, a proxy for tectonic deformation), distance to gas wells was highly significant for methane concentrations (P = 0.007; multiple regression), whereas distances to valley bottoms and the Appalachian Structural Front were not significant (P = 0.27 and P = 0.11, respectively). Distance to gas wells was also the mostsignificant factor for Pearson and Spearman correlation analyses (P < 0.01). For ethane concentrations, distance to gas wells was the only statistically significant factor (P < 0.005). Isotopic signatures (δ13C-CH4, δ13C-C2H6, and δ2H-CH4), hydrocarbon ratios (methane to ethane and propane), and the ratio of the noble gas 4He to CH4in groundwater were characteristic of a thermally postmature Marcellus-like source in some cases. Overall, our data suggest that some homeowners living <1 km from gas wells have drinking water contaminated with stray gases.

coral, coral reefs, Florida Keys National Marine Sanctuary, Florida Keys reefs, reef health

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

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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.