Flower Garden Banks National Marine Sanctuary
2008 Condition Report

Photo of yellow coral

Response to Pressures

The Flower Gardens sanctuary, like other marine sanctuaries, uses an “adaptive” management approach to resource protection, wherein threats are addressed when they are identified and understood. Adaptive management is a structured, iterative process of decision making, with the aim of reducing uncertainty over time via system monitoring and management plan updates. Adaptive management recognizes that management is an iterative learning exercise rather than a predetermined “solution” to an identified problem (Marshall and Schuttenberg 2006). The periodic review of the sanctuary’s management plan, including the development of specific action plans to address priority issues, provide a mechanism to apply adaptive management techniques to problems at the Flower Garden Banks.

This report identifies a number of issues that may indicate early signs of deterioration of the coral ecosystem in the Flower Garden Banks sanctuary. Some of these issues require more research to fully understand the problems and identify potential management actions to mitigate the impacts. However, it is important that, where appropriate, management options be considered as soon as possible, before changes become irreversible.  Existing management activities that relate to the pressures and recent concerns identified in this report are highlighted below.

Aquaculture and Artificial Reefs

The monitoring program at the Flower Garden Banks is designed to track some of the potential impacts of aquaculture and artificial reefs. Fish and invertebrate monitoring techniques employed on the banks are efficient at recognizing non-indigenous species even at low abundance. Unfortunately, the methods do not document changes in conditions that could be caused by changing levels of parasitism or disease resulting from interactions with aquaculture facilities. Should such facilities be placed near the sanctuary, it will be essential for the relevant authorities to require operators to monitor water quality and minimize the scale and extent of impacts to surrounding environments.

One possible effect of artificial reefs, according to Villareal et al. (2007), is the proliferation of the dinoflagellate that causes ciguatera poisoning in fish. In this regard, artificial reefs and petroleum platforms may work together to exacerbate the problem. Research remains to determine the extent to which this and other processes affect levels of ciguatera in the Flower Gardens sanctuary.

Current Minerals Management Service (MMS) guidelines require the removal of production platforms within a year of cessation of lease-block activity. The gas production facility in the Flower Garden Banks, and several others nearby, may go off-line in the next five to 10 years. Decisions on the fate of these facilities near the sanctuary have not been made, but the sanctuary will engage in discussions with the operators and the MMS to ensure that acceptable solutions are found.

Climate Change

Warming oceans have been linked to increasing levels and frequency of coral bleaching throughout the world’s oceans. The reefs of the Flower Garden Banks are not immune to these events, and therefore the sanctuary supports regular monitoring to detect the occurrence and extent of bleaching. When incidents are reported, scientists collect information on the degree and impacts. By tracking coral bleaching from year to year, the sanctuary can recognize events, identify related phenomena (e.g., hurricane-induced coastal runoff or anomalous temperature conditions) and take steps to reduce further impacts to the reef.

Temperature measurements have been made at the Flower Garden Banks for over 30 years. By itself, the information is insufficient to determine whether global warming is, as yet, affecting sanctuary resources directly. But data will continue to be gathered and made available to the larger ocean science community in order to contribute to our understanding of global climate change.

The sanctuary staff works to reduce other impacts and stressors in order to maximize reef community resistance and resilience in light of impending changes in climatic conditions, which the sanctuary cannot control. Recognizing that coral reef decline is typically due to the cumulative impacts of multiple stressors, management strategies should be directed at those potential impacts that can be controlled, thereby lessening the effects of climate change (Marshall and Schuttenberg 2006).

Coral Disease

The sanctuary regularly monitors the incidence and severity of coral disease at the Flower Garden Banks. The sanctuary sponsors regular research expeditions to the banks and, since the initial documentation of disease in 2005, has invited specialists in coral disease to conduct surveys and assessments during and after disease outbreaks. Current regulations prohibit the transport of corals or other organisms from other locations to the Flower Garden Banks, primarily because of the potential for disease introduction. There are currently no plans in place for treating or removing diseased animals from the sanctuary, but research is encouraged in order to identify the responsible disease pathogens. If a disease pathogen is related to a human-associated source, management actions may be appropriate to mitigate further introduction. It has been suggested, for example, that coral disease may be introduced via contaminated gear used by divers who had visited diseased areas. Preventative actions requiring disinfection of dive gear could eventually be considered at the Flower Garden Banks if this theory is proven.

Significant Regional Habitat

The original sanctuary boundaries were established without the benefit of detailed bathymetric mapping of the surrounding areas. Recently produced maps demonstrate the existence of adjacent habitats that were not included within the sanctuary boundaries but are likely important in maintaining the integrity of the sanctuary ecosystem. One such situation occurs at Stetson Bank, where a portion of the topographic feature was not included within the original boundary. Areas such as these should be considered for inclusion within the sanctuary. Furthermore, it is becoming evident that we need to view the reefs and banks of the northwestern Gulf of Mexico as an interconnected network of biological communities. It is apparent from past studies on certain species, such as sea turtles (Hickerson 2000), and recent observations of fish moving between banks in deep habitats that certain animals use resources on more than one bank during their lifetimes. The sanctuary is therefore expanding its programs to investigate the movement of animals among the banks, initially focusing on mantas and whale sharks.

Figure 23.	High-resolution bathymetry of Horseshoe Bank, located between East and West Flower Garden Banks. Source: NOAA/FGBNMS/UNH
Figure 23. High-resolution bathymetry of Horseshoe Bank, located between East and West Flower Garden Banks. (Source: NOAA/FGBNMS/UNH)

During public scoping meetings that are part of the sanctuary’s management plan review process, numerous comments were received from individuals, organizations and agencies indicating support for boundary expansion. A boundary expansion working group was formed by the sanctuary’s Advisory Council and a boundary expansion workshop was held. Invited experts, members of the sanctuary advisory council and the public participated. The working group evaluated and ranked 17 banks and associated topographic features, and seven alternatives for boundary expansion were developed and presented to the sanctuary advisory council. The council submitted its recommendation to modify the boundaries for Stetson Bank and East and West Flower Garden Banks. The alternative also included the creation of a sanctuary boundary around Horseshoe Reef, an area between East and West Flower Garden Banks (Figure 23). It also recommended boundaries to include the following areas: MacNeil, Rankin, 28 Fathom, Bright, Geyer, Sonnier, McGrail, and Alderdice banks.

The Fagatele Bay sanctuary staff works closely with its American Samoa government partners to promote sound use, conservation and awareness of the sanctuary's marine environment. The sanctuary staff also works throughout the territory to help the people of American Samoa understand and better utilize its marine resources.


To minimize the impacts of harvesting, current regulations limit fishing in the sanctuary to conventional hook-and-line methods. In spite of the restrictions on most types of fishing gear and the remote location of the sanctuary, there is concern that unanticipated fishing impacts are occurring at the Flower Garden Banks. During the public scoping process for management plan review conducted in October 2006, fishing was identified as a primary issue of concern. Many commented that the sanctuary should consider the use of no-take marine reserves within all or part of the area. The sanctuary advisory council has also identified fishing impacts as a priority issue and created a subcommittee to explore management strategies to address the concerns. The advisory council has developed both fishing and visitor use working groups. A fishing impacts workshop was attended by experts, advisory council members, and the public. These groups have recommended that the sanctuary proceed with an eight-year experimental closure to measure the effects of fishing and diving on the resources of the sanctuary. The experimental design of this closure was discussed during meetings scheduled for April 2008.

Enforcement and surveillance are difficult within the sanctuary due to the distance from shore. The sanctuary relies heavily on assistance from the U.S. Coast Guard and NOAA Fisheries for enforcement. Although both agencies have been very cooperative in the past, there is little enforcement within the sanctuary at this time. This will change in the near future, as a dedicated sanctuary vessel will be delivered in June 2008. This vessel will provide the ability to elevate the level of sanctuary surveillance and monitoring on site. Further, the Flower Garden Banks sanctuary will collaborate with NOAA Enforcement and the Coast Guard to carry representatives on board and conduct enforcement actions as necessary.

In response to the results of high levels of mercury and ciguatera, the sanctuary has issued a request for samples from fishers targeting winter populations of grouper and wahoo in the sanctuary. The sanctuary will collaborate with NOAA’s National Centers for Coastal Ocean ScienceNOAA’s Southeast Fisheries Science Center, the University of Texas Marine Science Institute, and the U.S. Food and Drug Administration to analyze the samples. The level and longevity of this investigation will depend on the availability of funds: however, the sanctuary is committed to providing vessel time and resources to obtain samples on at least a quarterly basis.

The sanctuary also engages in outreach efforts to reach harvesting communities and inform users of sanctuary resources and regulations. Current outreach to this community is achieved by providing information on the sanctuary Web site, occasional one-on-one encounters with fishers in the sanctuary, and a summary of fishing regulations distributed through outreach staff and NOAA Fisheries fishery reporting specialists (port agents). The Flower Garden Banks National Marine Sanctuary Advisory Council includes designated seats for representatives of both the recreational and commercial fishing constituent groups.

Invasive Species

The sanctuary supports long-term monitoring of the coral reef area of the sanctuary to examine the health of the ecosystem and to detect the appearance of invasive species. This regular monitoring provides the site with advance warning and provides the opportunity to take immediate steps to address invasive species issues. Invertebrate monitoring at East and West Flower Garden Banks is conducted primarily by contractors for the long-term benthic monitoring program, supported by NOAA and the Minerals Management Service. Sanctuary staff conduct monitoring of benthic communities at Stetson Bank. Fish monitoring is conducted through the long-term monitoring program as well as by volunteers associated with the Reef Environmental Education Foundation (REEF) and scientists from NOAA’s National Centers for Coastal Ocean Science (NCCOS). The policy related to exotic or invasive species within the Flower Garden Banks sanctuary is to remove them — if possible — as soon as they are encountered. Removal can only be undertaken by properly permitted entities.

Oil and Gas Infrastructure

Direct consultation is conducted with the Minerals Management Service regarding any proposed oil and gas development within a four mile buffer area around the banks of the sanctuary. In this way, sanctuary concerns are incorporated in the review of those proposals so that specific resource protection issues can be addressed. In addition, sanctuary regulations prohibit discharging pollutants in the sanctuary and disturbing the seafloor. Oil and gas exploration and development is not allowed within most of the sanctuary, an area designated by the MMS as “no-activity zones”.

The sanctuary also conducts training and information sharing activities to maintain collaborative relationships with the oil and gas industry. These include shared research and learning activities and one-on-one interactions with industry personnel and presentations at training sessions sponsored by industry for their offshore operations personnel. Such activities allow industry personnel the opportunity to learn about the sanctuary and the resources they are helping to protect when they comply with the highest operating standards. The sanctuary also participates in spill drills with the industry and MMS and works with regional response teams on contingency plans for spills and dispersant use policies.

Pollutant Discharges

The discharge of most pollutants and other material is prohibited by current sanctuary regulations. However, there are exceptions included in the regulations for “biodegradable effluents incidental to vessel use and generated by marine sanitation devices” approved by the U.S. Coast Guard, “graywater” (water from deck wash-down, showers and sinks) and engine exhaust. However, as previously noted, effluents discharged by approved marine sanitation devices can still contain a variety of pollutants, including high levels of nutrients and other contaminants. In addition, graywater may also contain harmful material, including detergents and bleach that are known to be toxic to corals. Further restrictions on the discharge of pollutants could be considered by the sanctuary, including the designation of the area as a “no discharge zone.”

Shipping and Transport

Historically, significant impacts on corals resulted from anchoring of large ocean-going vessels at the Flower Garden Banks. One anchoring incident can destroy hundreds of years of reef growth within minutes. This impact was minimized by the designation of the sanctuary in 1992, which prohibited anchoring with minor exceptions. In 2001, the sanctuary regulations were changed to prohibit all anchoring within the sanctuary. In addition, the sanctuary has been designated as a “no-anchor” area by the International Maritime Organization (IMO) so that the restriction appears on international charts most commonly used by foreign-flagged vessels. The designation of the Flower Garden Banks sanctuary as a no-anchor zone by the IMO was the first time in history that this action had been taken for the purpose of habitat protection. This no-anchor regulation is further strengthened through the NOAA Fisheries designation of the banks within the sanctuary as Habitat Areas of Particular Concern, protecting coral reefs by prohibiting anchoring by fishing vessels.

Visitor Use

Recreational divers constitute the largest user group within the sanctuary. To address potential impacts from this group, sanctuary staff frequently engages in outreach to divers through participation in dive-related trade shows, interactions with dive clubs, and interpretive programs. One such effort is the “Naturalist on Board” program aimed at recreational divers visiting the sanctuary aboard commercial dive charter vessels. Trained volunteer interpreters join commercial dive expeditions to convey educational messages and raise awareness of and appreciation for sanctuary resources.

Another potential impact from visitor use, especially those arriving on private vessels, is that caused by anchoring. Mooring buoys have been installed at prominent dive locations at the Flower Garden Banks to allow visitors to use the sanctuary without damaging its resources. In the future, consideration will have to be given to the number and placement of mooring buoys and management of the mooring buoy system. The 17 buoys currently in place in the sanctuary concentrate use in certain locations. As usage levels increase it may be necessary to disperse use by adding new buoys and temporarily removing others to limit inputs and allow damaged areas to recover. Also, regulations are in place that prohibits taking or injuring coral or coral reef organisms, preventing divers from collecting coral or other organisms.

Wildlife Interactions

Divers are drawn to the Flower Garden Banks for the opportunity to observe a variety of large marine animals, including sea turtles, manta rays and whale sharks. Often, divers are able to approach these animals at very close range, sometimes so close that the animals can be touched or in some cases held onto for a “ride.” Many times, the animals do not react negatively to such activities, giving the impression that these actions are innocuous. However, touching, chasing or otherwise harassing these animals may alter their behavior and have other detrimental impacts. Sea turtles are protected from these activities through the Endangered Species Act. The sanctuary may consider providing similar protection to rays, sharks and other large animals.


Hurricanes are a natural phenomenon that cannot be controlled or addressed directly by management actions. As with coral bleaching, the primary way to address the impacts of hurricane damage is to attempt to manage, as much as possible, the other stressors over which we do have some control. Coral reefs have existed with hurricanes for eons, and although reefs may experience severe damage from hurricanes, given enough time and good environmental conditions, the reefs will recover. However, reefs are under assault from a variety of other factors, and if they are also subjected to pollution, sedimentation and ecosystem manipulation, they will not recover as quickly as in the past. Knowledge of the dynamics of the ecology of coral reefs will aid in management of these systems that are subjected to natural impacts such as hurricanes.