Oil and gas platforms are producing 25-30 species of Caribbean obligatory reef fish. These platforms reside on thousands of square miles of featureless ocean floor. They provide obligatory reef species with the necessary resources for their survival. Post larval and juvenile reef fish can be found in remarkable numbers hiding in the thick mats of live rock, hydroids and coral that attach to the platform legs. Thousands of herbivores graze on the generous profile of algea, such as Angle fish, Blue Tang, Chubs, Parrotfish can feed on the algae that grows on the platforms. Plankton pickers such as Brown Chromas, Creol Wrasse, and Creol-fish are constantly feeding on and off the platforms. The invertebrate community living on the platforms supports several species of file fish, large schools of spadefish, and a multitude of sergeant majors and hogfish. Ultimately, the sharks, tuna, grouper, snapper, and jacks end up eating most of the fish that feed on and around the platforms.

These offshore platforms clearly produce fish rather than merely attract fish. Once the platforms are removed, the populations of invertebrates will die immediately and the obligatory reef fish will be lost to the biota if they survive the process of mandatory removal. Every year for the next 40 years, 100-120 platforms will be removed annually. Offshore of California, Dr. Milton Love is finding that platforms are creating excellent nursery habitat for several species of protected rockfish. Hundreds of thousands of rockfish are found at some platforms from post-larval stages to trophy size individuals. See underwater video of California platforms.

Attraction vs. Production Discussion

Whether artificial reefs attract fish or produce fish is a debate that U.S. fishery managers have not been able to settle over the last 30 years. Deliberations are divided into three sectors: attraction, production, and a middle ground that believes artificial reefs both produce and attract fish. In most cases, the latter is the most accurate description. Natural reefs and artificial reefs both attract and produce fish although some reefs tend to produce and some tend to attract fish. Oil and gas platforms are entirely responsible for producing 25-30 species of Caribbean reef fish on an anoxic continental shelf.

Production Evaluation

Production depends on the design, placement, and size of the artificial reef. Demersal (wide body) fish tend to be produced by the artificial reefs and pelagic (torpedo shaped) fish tend to be attracted to them. Bonsack 1989 suggested that artificial reefs fall along a gradient of production and attraction and discussed 5 biological events that would indicate whether artificial reefs are producing fish opposed to attracting fish. Artificial reefs are said to produce fish if they (1) provide additional food, (2) increase feeding efficiency, (3) provide shelter from predation, (4) provide new habitat for settling individuals that would otherwise have been lost to the population, and (5) indirectly, because fishes moving to artificial reefs create vacated space in the natural environment that allows replacement from outside the system. Also, increased production occurs when artificial reefs are placed in areas absent of natural reefs and designed for reef dependent species (Bohnsack 1989). Japanese artificial reef researchers regard the availability of energy or food sources near or on the artificial reef as the most important factor in the production of fish at artificial reefs. Video Production Evidence

Footage clearly illustrates 4 out of the 5 production events. The video shows herbivores grazing right on the platform, obligatory reef species feeding on plankton. Hundreds of algae eating fish can feed on the algae that grows on the platforms, while plankton eating species can feed on and off the platforms. The invertebrate communities living on the platforms are targeted by many species of schooling fish, which, in turn, are predated upon by many species of solitary predators which patrol the platforms and dine on the schoolers (1 & 2). The video demonstrates post-larval fish and juveniles of reef species utilizing the coral, sponge, and live rock for shelter from predation(3) (see Video). The Texas-Louisiana continental shelf is characterized by a turbid bottom water layer and platforms extend hard substrate above this zone. The video displays diverse assemblage of tropical fish communities and these fish would not succeed (4) on the terrain dominated by an nephloid layer of clay and silt. Evidence for the 5th production condition involves the local natural reefs and most of the 4,000 oil and gas platforms in the Gulf of Mexico are placed in areas absent of natural reefs.

Footage clearly illustrates 4 out of the 5 production events. The video shows herbivores grazing right on the platform, obligatory reef species feeding on plankton. Hundreds of algae eating fish can feed on the algae that grows on the platforms, while plankton eating species can feed on and off the platforms. The invertebrate communities living on the platforms are targeted by many species of schooling fish, which, in turn, are predated upon by many species of solitary predators which patrol the platforms and dine on the schoolers (1 & 2). The video demonstrates post-larval fish and juveniles of reef species utilizing the coral, sponge, and live rock for shelter from predation(3). The Texas-Louisiana continental shelf is characterized by a turbid bottom water layer and platforms extend hard substrate above this zone. The video displays diverse assemblage of tropical fish communities and these fish would not succeed (4) on the terrain dominated by an nephloid layer of clay and silt. Evidence for the 5th production condition involves the local natural reefs and most of the 4,000 oil and gas platforms in the Gulf of Mexico are placed in areas absent of natural reefs.

Design of Platforms and Production

Japan has the most active and innovative sustainable fisheries program in the world, and they utilize offshore platforms and artificial reefs for the foundation of their most ambitious projects. Offshore platforms closely resemble their most sophisticated and expensive artificial reefs and they are 10 times stronger and 10 times bigger than the best Japanese designs. Offshore platforms span the entire water column and as they mature in the water, they become covered with a thick mat of coral and/or calcareous live rock. Platforms have an advantage over artificial reefs since they provide substrate up through the entire water column while regular artificial reefs are limited to relief on the ocean floor occupying only 10%-40% of the water column. The presence of substrate throughout the water column greatly increases species diversity and available sources of food.

Placement of Platforms and Production

Japanese researchers suggest that the availability of nutrient resources is a key variable in production of artificial reefs. Ideal conditions for artificial reefs exist along the Texas and Louisiana continental shelf where there are literally thousands of square miles of gently sloping, nutrient rich, ocean floor. The Mississippi River and other tributaries supply the region with nutrients and maintains the largest ground fish population in the lower Continental U.S.

The Attraction vs. Production Dilemma

To supply a universally accepted resolution, marine researchers must overcome the difficult and expensive task of quantifying the production of artificial reefs. The communities of the obligatory reef fish and the oil and gas platforms would not exist if the substrate was not present in the region. The larvae would have no place to settle, their food source would be eliminated, and they would loose their shelter on an barren continental

Coral Communities on Drilling Platforms

For hundreds of thousands or millions of years, the Gulf of Mexico has had precious little hard bottom associated in its shallow sunlit waters. There is some hard bottom, however most of it is in depths too great to receive much light. Algae, corals, and other organisms requiring light cannot live there. But there is an exception to this: The Flower Garden Banks in the northwestern Gulf, at the edge of the continental shelf (110 miles SW of Galveston, TX).

These banks were created and brought into shallow water by the emergence of two salt domes in the ocean floor. The banks were raised into shallow water where light is sufficient to support organisms requiring such. Over millions of years, thriving coral reefs have developed on these banks in these clear, warm, offshore sub-tropical waters. Their significance has been recognized by the US government, and they have been declared the NOAA Flower Garden Banks National Marine Sanctuary. These reefs are isolated by hundreds to thousands of miles from other reefs in the Gulf.

Up until the 1940s, there was no other shallow hard-bottom in offshore waters of the Gulf. But then we began deploying oil and gas drilling platforms there. In all, ~6,000 major platforms have been installed. ~4,000 remain at this time (2002).

We have recently found that these platforms have acted as new settling substrate for corals. In fact, in a study of ~10-15 platforms within a 50-mile radius of the Flower Garden Banks, we have found that some of the platforms have substantial coral populations on them – of both reef-building (hermatypic) and non-reef-building (ahermatypic) types. The corals seem to be most abundant on the older platforms (> 12 yrs). These are all common Caribbean corals.

The platforms are also covered with other plants and animals associated with Caribbean coral reefs - algae, sponges, tunicates, crabs, sea fans, etc. They are also home to abundant populations of reef-associated fish. These include demersal reef fish, such as damselfish, parrotfish, and surgeonfish; semi-demersal fish, such as chromids; and pelagic fish, such as sharks, cobia, amber jack, etc. These artificial structures, over time, have become true living, breathing coral reefs.

Fish at Offshore Oil and Gas Platforms

One of the most unusual phenomena that we have observed are the seasonal visitations of large schools of fish migrating or aggregating to offshore platforms.

A number of species show up at certain platforms during certain times of the year. Hundreds of lobsters will march up a platform. As you can see, large schools of sharks and tarpon migrate to and school up at, offshore platforms. Cobia also school up in large numbers around the platforms.

These fish and crustaceans stay for a couple of days and then swim away to unknown destinations. We have also observed enormous schools of Atlantic mackerel and butterfish feeding in extraordinary numbers on zooplankton, under deep-water platforms during late summer and autumn year after year.

Platforms could potentially serve as excellent facilities to culture some rare, commercially valuable, deep-water invertebrates, such as deep-water sponges currently being used for producing powerful anti-cancer compounds (discodermalide; Gunasekera et al., 2002; Paul et al., 2002; Lin et al., 2004). Large plates could be seeded with coral larvae in the laboratory, and the spat could be reared to a point where they reach a size-refuge (Sammarco, 1982), carrying a higher probability of survivorship to the adult stage (Heyward et al., 2002). They could then be transported offshore and attached on the platform (Sammarco et al., work in progress) at the appropriate depth for optimum growth for a periods of up to 2–3 yrs.

Secondly, a large number of reef invertebrates such as sponges, bryozoans, gorgonians (sea fans), soft corals, etc. are known to live on offshore platforms (Gallaway & Lewbel 1981, Driessen 1989, Bright et al. 1991, Adams 1996, Boland 2002). The larvae of these organisms are carried by currents from their natal reefs around the Gulf of Mexico until they find suitable substrate upon which to settle (Lugo-Fernandez, 1998; Sanvicente-Anorva et al., 2000; Lugo-Fernandez et al., 2001;Pederson and Peterson, 2002). Many of these organisms are the same as those raised and sold commercially world-wide in the ornamental aquarium trade (Ogawa and Brown, 2001). Coral and sponge culture could simultaneously include both raising target organisms of specific value to commerce or research, and harvesting wild organisms occurring naturally on the platform legs.

Current State of Coral Reefs on a Global Scale

Coral reefs, and particularly coral populations themselves around the world are suffering high levels of mortality due to over-fishing, under-grazing, nutrient enrichment, deforestation and resultant runoff, pollution, increased sea surface temperatures, which induce mass coral bleaching, chemical pollution, physical disturbance, disease — both bacterial and fungal Shinn, 2003; Sammarco, 1996; Wilkinson, 1999; Gardner et al., 2003; Whittingham et al., 2003; McClanahan et al., in press). The federal protection of corals from harvest (see Sammarco, 2003) combined with the international agreements not to trade them (Harriot, 2003) also restricts their supply to scientists to conduct research on many of the causes of these ill effects and investigate possible mitigation techniques. The mariculture of corals would help to meet the demand for scientific research in the U.S. and elsewhere. They would also help to supply a need for corals to be introduced on damaged reefs during reef restoration activities on U.S. coral reefs, particularly in the Florida Keys (Sammarco, 1996; Becker and Mueller, 1999; Sammarco et al., 1999; Zobrist, 1999).

Role of Offshore Platforms

The purpose of culturing marine invertebrates such as these on platforms would be three-fold. Firstly, organisms such as these are in great demand within the ornamental aquarium trade. Many, such as corals and soft corals, are protected from harvest or take by federal legislation. In addition, they are protected from international trade by treaty. This is due to the excessive harvesting that has occurred in past years, decimating populations in certain tropical countries possessing coral reefs (Bruckner, 2001; Daw et al., 2001; Simpson, 2001; Tissot and Hallacher, 2003). Mariculture of these organisms would provide a domestic supply for them, obviating the need for importation of Indo-Pacific soft corals and the like. This would serve an additional function in that there is growing concern about the accidental or purposeful release of these Indo-Pacific ornamental species into coastal waters (Gulko, 2001; Semmens et al., 2004), with the possible impact of introducing yet more harmful species introductions (Minchin, 1999; Englund and Baumgartner, 2000; Shiganova, 2002). The mariculture of such local organisms would also initiate a new industry for the northern Gulf of Mexico , creating a new source of employment and revenue in the region and the nation. The demand for the organisms already exists; at this point, however, most of the supply is coming from overseas and represents lost revenue to the US (Sammarco 2003).

Potential Culture Species

In recent studies, it has been determined that scleractinian corals are expanding their geographic range within the northern Gulf of Mexico (Sammarco et al., 2003). In addition, from an ongoing study, it is also known that ahermatypic corals may be found extensively on platforms within 30 km of the shoreline in the far-western Gulf and within 120 km of the coast in the central-western Gulf (Sammarco et al., submitted). Platforms at the edge of the continental shelf in the northern Gulf of Mexico plus those just off the edge of the shelf are now known to be able to support coral populations. We know that the biogeographic range of corals in the Gulf of Mexico for both hermatypic (reef-building) and ahermatypic (non-reef-building) corals) extends as far west as the Matagorda Island and Brazos, South Addition regions, as far north as the inner West Cameron region, and as far south as 210 kms offshore near the Flower Garden Banks region (Sammarco 2003). The central and eastern regions of the northern Gulf of Mexico are scheduled to be surveyed soon to determine the limits of this group in this region.

Vision for Future

The ocean is Earth's last great untapped reserve. Many reef organisms possess natural chemical compounds which are unique to a given species (e.g., Faulkner, 2000). These are called complementary or secondary compounds (Sammarco and Coll, 1997). It is from these types of compounds that many valuable pharmaceuticals are derived (Shu, 1998; Duckworth, 2001; Dey et al., 2002; Haefner, 2003). Marine coral, sponges, mollusks, algae, and bacteria may possess bioactive compounds that can make a significant contribution to the health and nutritional industries (Pomponi 1999). Simple and abundant marine algae, let alone a host of other organisms which occur on the platforms, represent potential sources of pharmaceuticals agents, agricultural chemicals, food, industrial chemical feedstocks, and other useful products.

Some of the organisms which produce bioactive compounds, such as certain sponges, occur in deep water, are unreachable by SCUBA and occur only rarely in their natural environment (Duckworth, 2001). They require highly expensive equipment to gather — such as manned submersibles associated with large tender ships. Some of the valuable compounds isolated from these species, which have been shown to be highly effective in the treatment of certain types of cancer, occur in very low concentrations within their tissues (S. Pomponi, pers. comm.). In addition, they are so large and complex that it would be prohibitively expensive to synthesize and manufacture them, or even make functional derivatives in the laboratory (closely related compounds which function in the same way as the original, natural compound, but are patentable). Because of this, even the testing of these compounds for bioactivity and potential biomedical use requires quantities of these organisms which are extremely difficult and expensive to obtain (Duckworth, 2001). Nonetheless, they are required in order to extract appropriate amounts and this is causing a marked decline in some source populations.

Essential Fish Habitat (EFH/HACP) and Habitats of Particular Concern (HAPC) designations protects the habitat of federally managed organisms. The species and their habitats are delineated in the Fisheries Management Plans (FMPs) for coral and live rock, reef fish, and migratory fish. Many of the offshore platforms are covered with live rock organisms and some with coral, however, the structures are not considered protected under the FMP for Coral and Live Rock.

Over 50 federally managed species of fish and crustaceans utilize, to varying degrees, the platform substrate for feeding, spawning, mating, and growing to maturity. Again, platforms are not considered in any of their FMPs.

The offshore platforms are obviously EFH/HACP. If the platforms were recognized as “protected habitat”, National Marine Fisheries Service (NMFS) would have to recommend to Minerals Management Service (MMS) to not remove the platforms or take actions to mitigate the loss of habitat. You can help preserve thousands of these colossal offshore structures by expressing your opinion to NMFS during the Public Comment Period on EFH/HACP habitat determinations.

Regulatory guidelines outlined in the Magnuson-Stevens Act advises federal agencies to protect coral and “essential fish habitat” (EFH/HACP). The Gulf of Mexico Fisheries Management Council (GMFMC) is the responsible federal agency assigned with the task of evaluating and designating protected species and “essential fish habitat” (EFH/HACP).

Removal of a platform requires a federal permit (30 CFR 250.112). EFH/HACP provisions only govern actions by Federal agencies. If the platforms were considered “protected habitat,” this requirement makes their removal subject to NMFS review. That is not to say that a manmade substrate that is EFH/HACP can't be removed, only that removal can't be accomplished until NMFS has evaluated the action and determined the need for appropriate mitigative measures (i.e. impact avoidance, minimization, compensation).

Regulatory Mandate

Coral and Live Rock organisms in the Gulf has long been federally protected under the Magnuson-Stevens Act and implemented through 50 Code of Federal Regulations (CFR) Part 622. The Gulf of Mexico Fishery Management Council (GMFMC) has authority under the Magnusen-Stevens Fishery Conservation and Management Act to manage coral resources. GMFMC then completed a fishery management plan (FMP) in 1982. That FMP prohibited the take of stony corals and sea fans but allowed limited commercial harvest of soft corals (gorgonians).

In 1996, the Magnuson-Stevens Act was re-authorized and changed by amendments to emphasize the sustainability of the nation’s fisheries and establish a new standard by requiring that fisheries be managed at maximum sustainable levels and that new approaches be taken in habitat conservation. EFH/HACP is added to fishery management plans (FMPs) via the Gulf Council’s amendment process. EFH is broadly defined by the Act to include “those waters and substrate necessary to fish for spawning, breeding, feeding, or growth to maturity”. This language is interpreted or described in the 1997 Interim Final Rule [62 Fed. Reg. 66551, Section 600.10 Definitions] -- Waters include aquatic areas and their associated physical, chemical, and biological properties that are used by fish and may include historic areas if appropriate; substrate includes sediment, hard bottom, structures underlying the waters, and associated biological communities; necessary means the habitat required to support a sustainable fishery and the managed species’ contribution to a healthy ecosystem; and “spawning, breeding, feeding, or growth to maturity” covers a species’ full life cycle.

Conclusion

The MMS requires a federal action (30 CFR 250.112) to remove oil and gas platforms. If offshore platforms receive a federally managed status, then GMFMC and NMFS will have to advise the MMS that the platforms should not be removed or some mitigative action be taken to replace the loss of habitat. If a wide range of platforms received protected status, numerous abandonment and shut-down options would become available to the Gulf offshore oil and gas industry.

Endangered Marine Turtles

Offshore platforms are ideal habitats for marine turtles. Their forage and prey organisms are readily available all over the platforms. Several species of crustaceans, algae, sponge, and fish and sea urchins, are abundant and jellyfish always seem to be in the water in the NW Gulf of Mexico. The picture above is of the Hawksbill Sea Turtle (Eretmochelys imbricata) and they are the least observed marine turtle in the Gulf (MMS 1994).

The Hawksbill Turtle below is resting on a platform, presumably after feeding, offshore of Louisiana. The turtles are opportunistic feeders and will graze on algae, sponge, and sea grasses. They also forage on jellyfish, crustaceans, and sea urchins. As you can see, the structure also provides the turtle with a place to rest and sleep after feeding. Large turtles will often return to a favorite platform and a favorite site and will ware spots along the transoms were they rest. The loggerhead sea turtle (Caretta caretta) are frequent visitors to offshore platforms. Leatherbacks (Dermochelys coriacea), the most oceanic of the marine turtles, have been sighted at offshore platforms. They feed primarily on jellyfish but also consume crustaceans, fish, and some algae. The Hawksbills Sea Turtles have been on the Endangered Species List since 1970. The removal of marine turtle habitat is in violation of the Endangered Species Act.

This Sperm Whale (Physeter macrocephalus) was filmed next to a platform. The whale is swimming around a large school of squid. Enormous schools of squid are attracted to the massive structures during the day and they are extremely active at night under the lights that are maintained for operations. The whale was sighted swimming around a deep-water floating structure in 1,000 m of water on August 17th 2002.

Marine Mammals

By an order of a magnitude, the Bottlenose Dolphin are the most common marine mammal visiting offshore platforms and then Atlantic Spotted Dolphin are frequent visitors as well. Sightings of pods of Pilot Whales also occur often at deep-water structures.

Below is a list of federally managed species sighted or caught at oil and gas platforms. The list does not include migratory fish managed by NMFS.

Simple Name Scientific Name
King mackerel Scomberomorus cavalla
Spanish mackerel Scomberomorus maculatus
Cobia Rachycentron canadum
Cero Scomberomorus regalis
Little tuny Euthynnus alletteratus
Dolphin Coryphaena hippurus
Bluefish Pomatomus saltatrix
Red drum Sciaenops ocellatus
Mutton snapper Lutjanus analis
Schoolmaster Lutjanus apodus
Red snapper Lutjanus campechanus
Cubera snapper Lutjanus cyanopterus
Gray(mangrove) snapper Lutjanus griseus
Dog snapper Lutjanus jocu
Lane snapper Lutjanus synagris
Yellowtail snapper Ocyurus chrysurus
Wenchman Pristipomoides aquilonaris
Wermilion snapper Rhomboplites aurorubens
Silk snapper Lutjanus vivanus
Rock hind Epinephelus adscensionis
Speckled hind Epinephelus drummondhayi
Yellowedge grouper Epinephelus flavolimbatus
Red hind Epinephelus guttatus
Jewfish Epinephelus itajara
Red grouper Epinephelus morio
Warsaw grouper Epinephelus nigritus
Snowy grouper Epinephelus niveatus
Black grouper Mycteroperca bonaci
Yellowmouth grouper Mycteroperca interstitialis
Gag Mycteroperca microlepis
Scamp Mycteroperca phenax
Yellowfin grouper Mycteroperca venenosa
Marbled grouper Epinephelus inermis
Greater amberjack Seriola dumerili
Lesser amberjack Seriola fasciata
Almaco jack Seriola rivoliana
Banded rudderfish Seriola zonata
Gray triggerfish Balistes capriscus
Hogfish Lachnolaimus maximus
Spiny lobster Panulirus argus
Stone crab Menippe mercenaria

BioMedical Applications

The live rock communities may provide a rich source of critical pharmaceutical medicines and health products. Many species of algae, hydroids, sponges, mollusk (clams, slugs, snails etc.), and barnacles are being investigated. A family of invertebrates, called bryozoans, contains symbiotic bacteria that are known to produce a compound that inhibits the growth of cancerous cells (Russo 2000).

The most complex community living under the platforms are the invertebrate-algae community or otherwise known as “live rock” that attaches to the platform’s pilings and transoms. Drifting plankton continually bombards the platform’s profile. It provides the attaching organisms the necessary substrate to anchor and feed on the passing nutrients.

Bryozoan

The Bryozoan Bugula neritina lives in the Gulf and can potentially be commercially harvested from platforms. This organism is being tested as a treatment against non-Hodgkin’s lymphoma and chronic leukemia (MMS 2002). So far, ~ 20 out the 4,000 platforms have been investigated. A final report on the research should be completed in Dec 2002 (MMS).

Bacteria

Marine Bacteria and members of Actinobacteria in particular, have yielded numerous bioactive compounds.

Algae

Marine algae begin to inhabit platforms almost immediately after installation and they continue to compose a large % of the biomass as the platforms age and develop more complex live rock communities. Marine algae are utilized for a wide variety of pharmaceuticals and are used as a culture medium for microorganisms in medical and biological research.

Molluscs

Pharmacological uses of mollusc-derived compound