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Louisiana's offshore oil and gas industry began in 1947 when the first well was drilled out of sight of land south of Terrebonne Parish. Today over 3,700 offshore oil and gas platforms have been installed, supplying 25 per cent of the United States' production of natural gas and 12.5 per cent of its oil. In addition to meeting the world's energy needs, these structures also form one of the world's most extensive defacto artificial reef systems. However, federal regulations require that these structures be removed within 1 year after the lease is terminated. Disposal of obsolete offshore oil and gas structures is not only a net financial liability for private industry but can be a public loss of productive marine habitat. In 1986 the Louisiana Fishing Enhancement Act was signed into law, in response to the National Fishing Enhancement Act, creating the Louisiana Artificial Reef Program. This program was designed to take advantage of fishing habitat opportunities offered by these obsolete platforms. Since the program's inception 22 reef sites, utilising the components (jackets and decks) of 58 obsolete platforms, have been created off Louisiana's coast. The use of obsolete oil and gas platforms in Louisiana has proved to be highly successful. Their large numbers, design, longevity, and stability have provided a number of advantages over the use of traditional artificial reef materials. The participating companies also save money by converting the structure into a reef rather than abandoning it onshore; these companies are required to donate a portion of the savings to the state to run the artificial reef program. One disadvantage, however, is that the large size of these platforms restricts the distance to shore where they can be sited. To achieve the minimum clearance of 16 m over a submerged structure, as required by the Coast Guard regulations, the platforms must be placed in waters deeper than 30 m. Waters of this depth are found between 22 km and 115 km from shore on Louisiana's gently sloping continental shelf, making them almost inaccessible to many anglers. Funds generated by the program, however, can be used to develop reefs closer to shore if alternative low profile materials are used. Due to high maintenance costs of both the structure and aids to navigation, the increased liability exposure and the undetermined cost of removing the structure once it becomes a hazard to public safety and navigation, leaving the structures standing in place has thus far proved not to be a viable option in Louisiana.

Sand seatrout usually represent from 5-7% of trawl catches by weight, 8-10% by number, and consistently rank among the top 5 most abundant species in demersal surveys. Sand seatrout mature at 140-180 mm TL, begin to enter the late developing, gravid, or ripe stages around 180 mm TL, and first spawn at 12 months. Spawning occurs primarily from March through September with distinct peaks in both March-April and August-September. Spawning initially takes place in midshelf to offshore waters and moves shoreward as the season progresses, with most occuring in the lower estuary and shallow GOMEX (7-15 m water depth). Larvae are primarily collected in water depths of <25m, more are collected at night than during the day, and they• are somewhat surface•oriented but become increasingly demersal with size. In pass studies, larval sand seatrout are also more abundant on night flood tides than at other times. Larvae migrate into shallow areas of the estuary where they remain until at least 50-60 mm TL after which they move to deeper water. Mean size predicted by regression was 250, 425, and 573 mm TL at ages I, II, and Ill, with a typical lifespan of 1-2 years and possibly up to 3 years. Total annual mortality approaches 100% based on trawl data if the lifespan is one year and 90% if two years. Distribution of sand seatrout appears restricted more by water temperature than salinity. Electrophoretic evidence is unclear whether sand seatrout should be recognized as distinct from weakfish. Evidence provided by otolith aging of larvae and differences in larval pigmentation, however, supports the separation of two co•occurring morphological types and suggests separate populations of sand seatrout in the northern Gulf of Mexico. Sand seatrout, C. arenarius, are harvested both commercially and recreationally in the Gulf of Mexico (GOMEX) and are one of the most important finfish in commercial fisheries of the northern Gulf, 35 contributing a major portion of the industrial bottomfish and foodfish fleet catches (Gutherz eta/., 1975). Sand seatrout usually represent from 5-7% of trawl catches by weight (e.g., Moore eta/.,

Louisiana's offshore oil and gas industry began in 1947 when the first well was drilled out of sight of land south of Terrebonne Parish, Louisiana. Today, over 3,837 offshore oil and gas platforms have been installed, supplying 25% of the United States' production of natural gas and approximately 13% of its oil. In addition to meeting the world's energy needs, these structures also form one of the world's most extensive defacto artificial reef systems. However, Federal regulations require that these structures be removed within 1 year after the mineral lease is terminated. Disposal of obsolete offshore oil and gas structures is not only a financial liability for private industry but can be a loss of productive marine habitat. In 1986 the Louisiana Fishing Enhancement Act was signed into law, in response to the National Fishing Enhancement Act, creating the Louisiana Artificial Reef Program. This program was designed to take advantage of fishing habitat opportunities offered by these obsolete platforms. Since the program's inception, 25 reef sites, utilizing the components jackets and decks) of 71 obsolete platforms, have been created off Louisiana's coast. The use of obsolete oil and gas platforms in Louisiana has proved to be highly successful. Their large numbers, design, longevity, and stability have provided a number of advantages over the use of traditional artificial reef materials. The participating companies also save money by converting the structure into a reef rather than abandoning it onshore. They then are required to donate a portion of the savings to the state to run the artificial reef program. One disadvantage, however, is that the large size of these platforms restricts the distance from shore where they can be sited. To achieve the minimum clearance of 16 m over a submerged structure, as required by the Coast Guard regulations, the platforms must be placed in waters deeper than 30 m. Waters of this depth are found between 22 km and 115 km from shore on Louisiana's gently sloping continental shelf, making them almost inaccessible to many anglers. Funds generated by the program, however, can be used to develop reefs closer to shore if alternative low profile materials are used. Due to high maintenance costs of both the structure and aids to navigation, the increased liability exposure and the undetermined cost of removing the structure once it becomes a hazard to public safety and navigation, leaving the structures standing in place has thus far proved not to be a viable option in Louisiana. INTRODUCTION Offshore oil and gas platforms began functioning as artificial reefs in 1947 when Kerr McGee completed the world's first commercially successful oil well, out of sight of land in 5.6 m of water, 70 km south of Morgan City, Louisiana. With the capability of drilling offshore and the development of new technologies, Louisiana's offshore oil and gas industry quickly expanded. In 1993, Minerals Management Service estimated there are over 3,746 (Table 1) platforms in the northern Gulf of Mexico, in water depths up to 609 m. In addition to supplying 25% of the annual U.S. production of natural gas and approximately 13% of its oil, the platforms also form the world's largest artificial reef systems.

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