Flower Garden Banks National Marine Sanctuary
Condition Report 2009–2021

Executive Summary

Flower Garden Banks National Marine Sanctuary (FGBNMS) is the only sanctuary located in the Gulf of Mexico. Situated 80 to 125 miles (130 to 200 km) off the coasts of Texas and Louisiana, FGBNMS ranges in depth from 52 to 722 feet (16 to 220 m) and includes thriving shallow-water coral reefs, algal-sponge communities, and deeper mesophotic reefs comprised of black coral, octocoral, and algal nodule habitats. When first designated in 1992, the sanctuary consisted of East Flower Garden Bank (EFGB) and West Flower Garden Bank (WFGB), home to some of the healthiest coral reefs in the Atlantic and Caribbean region. Stetson Bank was added to the sanctuary in 1996. In 2021, portions of 14 more primarily mesophotic banks were added to the sanctuary, expanding the sanctuary in size from 56 to 160 square miles. The 17 reefs and banks that make up FGBNMS are a combination of small underwater mountains, ridges, troughs, and hard-bottom patches perched atop underlying salt domes along the continental shelf to form a chain of protected habitats for ecologically and economically important species (including fish, sea turtles, and manta rays) across the continental shelf in the northwestern Gulf of Mexico.

The first condition report, which assessed resources in EFGB, WFGB, and Stetson Bank, was published in 2008. This condition report marks an updated and comprehensive description of the expanded sanctuary and used the best available information to assess the status and trends of the sanctuary's resources and ecosystem services. The report is structured around a Drivers-Pressures-State-Ecosystem Services-Response (DPSER) model. The report provides a comprehensive update of the status and trends of sanctuary resources from 2009 to 2021, covering the broad categories of water quality, habitat, and living resources. The report also includes the first evaluation of the status and trends of ecosystem services—the ways humans derive benefits from different ecosystem attributes that they care about for their lives, lifestyles, and livelihoods. The report also identifies gaps in current monitoring efforts, as well as factors that may require monitoring or potential management actions in the coming years. The ratings and conclusions in this report generally represent the shared perspective of sanctuary managers and subject matter experts on resource status, and will inform future management, primarily through the management plan review process, to address challenges stemming from pressures on resources.

Drivers and Pressures

The primary pressures identified for FGBNMS included climate change, fishing, marine debris, oil and gas operations, and invasive species. The climate-related pressures of greatest concern are rising ocean temperatures, ocean acidification, and deoxygenation and hypoxia. Some of the greatest challenges for coral reefs related to climate change include marine heatwaves, hypoxic events, and ocean acidification. Commercial and recreational fishing in FGBNMS contribute to the economy, support jobs, and provide food in the Gulf of Mexico region, but also impact sanctuary habitats and species through harvest, bycatch, seafloor impacts, and lost gear. Marine debris in the ocean is a growing threat to marine life and biological diversity, even in remote offshore locations like FGBNMS, where it has been found across all habitats. While major impacts from oil and gas operations, such as discharges and spills, are rare, they are of great concern to sensitive ecosystems like those in the sanctuary. Invasive species, such as lionfish, also put pressure on native species by outcompeting them for food.

The societal drivers behind these pressures are beyond what FGBNMS can manage locally, as they are primarily influenced by global and regional demand for goods and services. However, it is helpful to understand the connections between drivers and pressures in order to prioritize management actions. Drivers include economic factors, such as income and spending; demographics, like human population growth and development; and societal values, such as levels of conservation awareness, political affiliations, or changing opinions about the acceptability of specific behaviors (e.g., littering). All drivers influence pressures on resources by changing human preferences and, consequently, the levels of activities needed to meet the demand for resources and services.

State of the Resources

Water Quality

Overall, FGBNMS had good water quality throughout the assessment period, as the sanctuary is not affected by some of the issues present at coastal sites, such as point source pollution. For example, there was no information to suggest eutrophication has occurred in FGBNMS, and water quality risks to human health, such as poor water quality from harmful algal blooms, have not been documented. The limited data available for the expansion area indicated that nutrient and contaminant levels were below thresholds of concern.
Of significant concern, however, are the changing conditions associated with climate change. Sea surface temperatures have increased globally and ocean acidification is affecting water quality worldwide. Increased ocean temperatures at FGBNMS (both at the surface and at depth) have resulted in more frequent coral bleaching events. Although climate change has not caused severe degradation at EFGB, WFGB, and Stetson Bank to date, increased seawater temperatures and increased periods of sustained extreme temperatures led to major coral bleaching events in 2010 and 2016. Within FGBNMS, pH is decreasing; however, aragonite saturation state and calcification rates have remained high and conditions are not currently causing coral dissolution or erosion. While data were limited across mesophotic habitats at these banks, climate models show that climate change has the potential to influence the status and trends of all sanctuary resources in the future, and it is important that FGBNMS works with partners to address data gaps moving forward.

Habitat

FGBNMS includes a diverse array of habitats, including coral reef, coral community, algal nodules, coralline algae reef, deep reef, and soft substrate. The shallowest area of the sanctuary contains coral reef and coral community habitats, representing 1% of the sanctuary, while the remainder of the habitats, including algal nodules, coralline algae reef, deep reef, and soft substrate habitats, are mesophotic make up 99% of the sanctuary.

The sanctuary's offshore location offers insulation from the impacts of coastal development and other direct anthropogenic disturbances to habitats. Therefore, FGBNMS habitats were found to be relatively undisturbed and in good/fair condition overall. Coral cover on the reef cap of EFGB and WFGB remained stable during the study period, and there was an increase in cover of crustose coralline algae (EFGB) and sponges (EFGB, WFGB). At Stetson Bank, however, continued declines in sponge cover and fire coral were reported. Mesophotic coral densities within the expansion area appeared high compared to those in other regions, and although marine debris was present at all the banks, its impacts were limited and it did not appear to be degrading overall habitat quality.
Oil and gas exploration and development in the area has been subject to protective regulations that have, by all accounts, been effective in controlling both intended and accidental releases. Fortunately, no oil or spill impacts were detected at FGBNMS following the 2010 Deepwater Horizon oil spill. While there are no indications of current impacts from contaminants, data is limited and analyses have not been performed across all habitats.

Living Resources

Living resources in FGBNMS are diverse and, as such, were characterized by a range of statuses and trends. Not all living resources in the sanctuary have been fully documented, but are best characterized across shallow coral reef and coral community habitats. In the sanctuary's mesophotic habitats, more information is needed about ecological interactions and individual species' roles in the ecosystem. Therefore, groups of ecologically important species were evaluated for their combined contributions to the ecological integrity of their respective ecosystems. Foundation species for the shallow reef zone at EFGB and WFGB included the scleractinian coral Orbicella franksi, reef fish (brown chromis and bluehead wrasse), and the long-spined sea urchin. At Stetson Bank, foundation species included the long-spined sea urchin, brown chromis and bluehead wrasse, as well as fire coral and a newly predominant sponge species, Neofibularia nolitangere. For mesophotic habitats at EFGB, WFGB, and Stetson Bank, two species of fish, roughtongue bass and threadnose bass, were considered foundation species due to their abundance.

Monitoring data indicated that foundation coral, sponge, fish, and urchin species are abundant and persistent at EFGB, WFGB, and Stetson Bank; however, emerging diseases warrant close continued monitoring of these species. In mesophotic habitats, robust long-term datasets are needed to track both status and trends of foundation species. Significant changes across three species were recognized: 1) populations of long-spined sea urchins at all three banks remain greatly diminished compared to pre-1983 levels; 2) the die-off of fire coral and the sponge Chondrilla nucula at Stetson Bank that precipitated a complete shift in the benthic community on the bank; and 3) an increase in benthic macroalgae that has been observed across all locations. Each of these species will be closely monitored moving forward, along with the impacts of the observed changes. Further, coral and long-spined sea urchin diseases pose a continuing threat to the health of foundation species at FGBNMS.
Manta rays, lobsters, the snapper-grouper complex, and parrotfish were considered focal species for EFGB, WFGB, and Stetson Bank. Focal species selected for the 14 banks in the sanctuary expansion area included: whale sharks, manta rays, the snapper-grouper complex, greenblotch and redband parrotfish, and crinoids. Each was chosen because of either their ecological, economic, and/or recreational importance.
Manta rays continue to use the sanctuary regularly, with evidence suggesting that individual rays return to these areas over extended periods of time. The manta rays at EFGB, WFGB, and Stetson Bank tend to be smaller and younger than those observed elsewhere, which suggests that the area may serve as a nursery habitat for these animals (Stewart et al., 2018). Lobster populations have remained low in the sanctuary since monitoring began in 2010. Monitoring data suggest focal fish populations at EFGB, WFGB, and Stetson Bank have been stable, although it is likely that commercial and sport fishing has reduced populations of large-bodied grouper and snapper species to some extent.

In the expansion area, further information on the frequency and size of manta rays will be needed in order to determine whether these 14 banks also serve as nursery habitat for these animals. The expansion area provides highly valuable habitat for reef-associated grouper, snapper, and parrotfish species; however, long-term data are needed, particularly for evaluating the time and location of reef fish spawning aggregation areas, some of which are reported to occur within the expansion banks. Although there is very little sanctuary-specific information for whale sharks, they are considered a focal species because their size and gentle nature makes them iconic and attractive to divers and snorkelers. Whale sharks are occasionally observed in the sanctuary during the summer months. Crinoids, also known as sea lilies, were selected as focal species in the expansion area due to their importance as indicators of ecosystem health. They are absent from the shallow reef caps in FGBNMS but are present in mesophotic depths. Thirty-two crinoid morphospecies have been documented in the sanctuary, including stalked and non-stalked species, and further research is needed to more fully assess crinoid communities within mesophotic depths.

Non-indigenous species, including lionfish and orange cup coral, have been found within all banks of FGBNMS. The regal demoiselle has been found on EFGB, WFGB, and Stetson Bank. To date, the impacts from these invasive species appear to have been minimal. In the case of lionfish, believed to be the most threatening of the non-indigenous species currently known to be present in the sanctuary, efforts are being made to control populations through removal, and thus far, no measurable declines in native biomass have been correlated with with the establishment of lionfish at the sanctuary. Orange cup coral, which has been present in the sanctuary for at least 30 years, does not appear to be outcompeting native coral species on natural substrate, preferring shaded areas. The impact of the recent arrival of the regal demoiselle on native fish populations is uncertain, and the possibility of this species directly competing with native damselfishes is of particular interest.

Overall, fish, coral, and sponge community data indicated dense and stable assemblages in FGBNMS, as well as high genetic connectivity the broader region. While the remoteness of the banks results in fewer species than many similar habitats in the region, the communities are well developed, and in some cases (e.g., hermatypic corals), in much better condition than other locations. Nonetheless, biological diversity must be explored further, as additional species continue to be documented and new species have been recently discovered in deeper habitats within the sanctuary. In addition, range expansions and shifts in species distribution as a result of changing ocean conditions due to climate may contribute to changes in biodiversity.

Maritime Heritage Resources

Maritime heritage resources were not rated as there were no known significant resources of this nature within sanctuary boundaries.

State of Ecosystem Services

Ecosystem services are the tangible and intangible benefits that humans receive from natural and cultural resources. Seven types were considered in this report: commercial harvest, consumptive and non-consumptive recreation, science, education, heritage, and sense of place.

Commercial Harvest

Commercial harvest evaluates the capacity of the sanctuary to support commercial market demands for seafood products. Commercial fishing data in FGBNMS were difficult to interpret due to the small size of the sanctuary compared to the large reporting areas in the Gulf of Mexico. Data on landings and revenue were available for the entire Gulf of Mexico region rather than FGBNMS specifically. Although the number of vessels and effort for mackerel and reef fish appeared to be stable, overall fishing effort may have increased in the region. As noted previously, grouper and snapper densities at EFGB, WFGB, and Stetson Bank were stable, but limited data prevented trend analysis in the expansion area. Experts noted that regional landings for some species, like snapper, have increased while others have declined.

Consumptive Recreation

Consumptive recreation is a term used to describe recreational activities that may result in the death of or disturbance to wildlife, or the destruction of natural habitats. Recreational fishing is the primary consumptive recreation activity that occurs in FGBNMS, and takes place from either private or rented boats, or for-hire charter/party boats. Recreational catch data were not available for locations within FGBNMS, but data for the region were available on a state-wide basis. Fish species that are typically targeted by recreational fishers are widely distributed across the northwest Gulf of Mexico, including the banks of the sanctuary. Offshore fishing is a popular activity off each of the five Gulf coast U.S. states, and many targeted species, like amberjack and vermillion snapper, occur in high abundance in association with the reefs, banks, and hard-bottom habitats of the region. However, the intensity of recreational fishing and harvest levels in the sanctuary were not documented well enough to determine a status or trend for this ecosystem service.

Non-consumptive Recreation

Non-consumptive recreation includes recreational activities that do not result in the intentional removal of or damage to natural resources, such as scuba diving in the sanctuary. Indicators considered to evaluate this service included the number of divers that visited FGBNMS, published underwater photographs taken in the sanctuary, and citizen science surveys.
There have been no studies specific to non-consumptive recreational activities in FGBNMS; however, evidence suggests a decline in visitation in recent years. There is only one dive charter in operation, which limits the number of recreational divers that can access the sanctuary. The number of citizen science surveys declined, and that was likely related to the limited number of dive boats and trips to the sanctuary. While the environment and infrastructure can clearly support more nonconsumptive recreation in the sanctuary, other factors have contributed to a decline in visitation in recent years, such as increased costs of travel and vessel operation, as well as impacts resulting from the COVID-19 pandemic.

Science

Science as an ecosystem service is defined as the capacity to acquire and contribute information and knowledge, and has long been an important and growing ecosystem service for FGBNMS. Research activities, publications, science capacity, and partnerships have all increased over the past 10 years since the procurement of the research vessel Manta in 2008, despite the fact that accessing the sanctuary to conduct research presents challenges (i.e., remoteness, rough weather, limited number of research vessels, a limited number of research institutions nearby, small science staff, increasing costs of offshore operations). FGBNMS has successfully worked with partners to support research cruises to study shallow coral reef and mesophotic systems, make new scientific discoveries, expand monitoring (to include, for example, ocean acidification), and conducting mapping to assist with sanctuary expansion. The FGBNMS long-term monitoring program is one of the longest-running programs in the Gulf of Mexico and Caribbean region, and in the National Marine Sanctuary System. Additionally, FGBNMS is at the forefront of coral reef research and monitoring in the Gulf of Mexico. With the sanctuary expansion in 2021, additional science support will be needed in the future, given the additional 14 reefs and banks now within the sanctuary's boundaries.

Education

Education and outreach is another important ecosystem service that has benefitted a wide range of audiences, participants, partners, communities, and networks locally, regionally, nationally, and internationally. Education and outreach efforts at FGBNMS have consistently grown, despite the fact that the sanctuary cannot be easily accessed by the general public. Because of this limitation to access, building awareness of the sanctuary through a variety of education and outreach programs is a priority for staff.
A significant success has been collaborating with local, regional, national, and international partners on citizen science lionfish control programs, thus increasing awareness about invasive species while also educating people about FGBNMS and coral reef ecosystems. Sanctuary staff were adaptable during the COVID-19 pandemic, and the advent of virtual presentations enhanced the sanctuary's reach to a much broader audience. This was important in the context of the sanctuary expansion in 2021, as it allowed the delivery of information to more Louisiana-based audiences.

Heritage and Sense of Place

Attention to heritage, the recognition of historical and heritage legacy and cultural practices, has increased in the past decade as information about paleoshorelines and historical fishing efforts have been explored. FGBNMS has maintained a long-standing relationship with offshore energy development entities in the Gulf of Mexico region. Scuba diving and research communities, who played important roles in the nomination and original designation of the sanctuary, continue to actively support conservation and protection efforts. Many of the sanctuary's banks and reefs were named after researchers and energy industry professionals. Sanctuary facilities, based at historic Fort Crockett, are also part of the heritage of Galveston Island. There may be an undiscovered history of occupation by native peoples during low sea level stands, but more work is needed to understand paleo landforms that could connect the sanctuary to this ancient heritage.

For a remote location like FGBNMS, a sense of place (aesthetic attraction, spiritual significance, and location identity) revolves around building awareness for this unique ecosystem in the Gulf of Mexico. Fishers, divers, and researchers were likely the first to develop an appreciation for the sanctuary area, as they have had the means to visit and create personal experiences. However, as sanctuary outreach has increased, a sense of awareness, admiration, and wonder have grown among the general public, inspiring numerous articles, books, videos and films, art projects, and exhibits. FGBNMS has been a diving destination for five decades because of its iconic species and the fact that it has the highest and most persistent coral cover of any reef in the western Atlantic basin. Though distance from shore limits access and reduces public awareness of the sanctuary, outreach and education efforts have generated national and international recognition and have highlighted the value of research and the potential for effective conservation in a highly industrialized region. The health of the sanctuary also contributes to awareness of its conservation value beyond the immediate community.

Response to Pressures

Significant responses to the pressures identified in the last condition report included investigations of changing ocean conditions, such adding ocean carbonate sampling to the sanctuary's long-term monitoring program in partnership with Texas A&M University Corpus Christi, as well as collaborating with the research community to investigate a localized mortality event at EFGB in 2016. Targeted research, monitoring, and control projects with citizen scientists have assisted with management efforts to remove invasive lionfish and reduce pressure on native prey species. The deployment of hydrophones has assisted with FGBNMS soundscape research and established an acoustic baseline at select banks, and these data will help classify acoustic signatures of the site, including relative contributions of human-produced noise, the characteristic sounds of marine wildlife, and geophysical sources. Ongoing efforts to address marine debris in the sanctuary have gained significant momentum, and a $14.9 million grant awarded to the National Marine Sanctuary Foundation will support large marine debris removal in five national marine sanctuaries, including FGBNMS. This project, in addition to the efforts currently underway as part of the Mesophotic and Deep Benthic Communities Restoration project portfolio, developed in response to the Deepwater Horizon oil spill, plans to target lost scientific equipment, derelict shrimping nets, and salvage gear remaining from treasure hunting activities. This report identifies gaps in current monitoring efforts, as well as pressures that may require monitoring and remediation through management actions in the coming years. The information in this report will inform the next FGBNMS management plan to ensure the sanctuary continues to thrive and address priority needs.