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Fishery Bulletin 88(4), 1990 



Figure 1 



Sample page from offshore logbook program. 



ing method used by charterboat operators and private 

 vessel anglers. However, Dugas et al. (1979) reported 

 that trolling was the dominant fishing method used by 

 private vessel anglers in Louisiana, with bottom fishing 

 second. 



Highest catch rates while trolling off the Louisiana 

 coast by charterboat operators from 1982 to 1985, 

 calculated as number of fish caught/boat hour (CPH), 

 were 9.19 for dolphin in 1982 and 9.04 for Spanish 

 mackerel in 1985 (Brusher et al. 1984, Brusher and 

 Palko 1985, 1987). Bottom-fishing catches off the Loui- 

 siana coast by charterboat operators consisted chiefly 

 of Atlantic croaker, red snapper, sand seatrout C. 

 arenarius, unidentified seatrout, grey triggerfish 

 Balistes capricus, bluefish, and king mackerel, with 

 highest CPH's of 23.45 for sand seatrout and 12.38 for 

 Atlantic croaker in 1984 (Brusher et al. 1984; Brusher 

 and Palko 1985, 1987). 



A method by which to test the success or value of 

 an artificial reef and develop a data base on species 

 composition is by tracking the number of fish caught 

 over time, under the assumption that catch per unit 

 effort (CPUE) of the target species is proportional to 

 the abundance of fish. The resultant CPUE can then 

 be used as a measure of relative abundance of fish, and 

 the effects of an artificial reef such as an oil or gas plat- 

 form can be assessed. For the target species of both 

 the avid recreational angler and researcher, CPUE is 

 a good index of relative abundance (Peterman and 

 Steer 1981, Casselman et al. 1985, Richards and 

 Schnute 1986). LIsers of such data, however, should be 



aware that the variability of CPUE estimates can be 

 a problem with any sampling program and can change 

 with different sampling gears. However, Casselman 

 et al. (1985) found that the coefficient of variation of 

 angling catches by experienced, avid, or professional 

 fishermen such as charterboat operators was signifi- 

 cantly lower than for other sampling techniques such 

 as trawling, electrofishing, gillnetting, and trapnetting. 

 The goals of this study were to (1) record and quan- 

 tify the catch rates and species composition for fish 

 caught by recreational anglers and charterboat opera- 

 tors at or near oil and gas platforms off the Louisiana 

 coast; (2) compare our results with past studies from 

 the northern Gulf of Mexico; and (3) determine the 

 utility of using CPUE estimates of the target species 

 caught near the platforms as an index of their relative 

 abundance. 



Materials and methods 



Volunteers (120) were solicited to maintain log books 

 from fishing clubs across Louisiana. In addition, 23 

 charterboat operators listed in National Marine Fish- 

 eries Service records, and Coleman (1984) volunteered 

 to maintain logbooks. Study participants were provided 

 with logbooks and program information. Monthly con- 

 tact was made with study participants to ensure their 

 assistance. 



Logbook design was based on the Lake Erie Angler 

 Diary Program (Sztramko 1986) and logbook criteria 



