the Everglades Drainage District, dug 

 the St. Lucie Canal between 1916 and 

 1924 to help control flood waters 

 from Lake Okeechobee. It was con- 

 nected to the South Fork of the St. 

 Lucie River and, when opened, had a 

 discharge capacity of 5,000 cubic 

 feet per second (cfs). Control of 

 the canal was transferred to the 

 U.S. Army Corps of Engineers in 1930. 

 The discharge capacity was expanded 

 to 9,000 cfs (with the lake stage at 

 15.6 ft) in 1949. 



the Okeechobee Waterway Project, was 

 funded by the U.S. Army Corps of 

 Engineers to perform a creel census 

 with a statistical analysis correlat- 

 ing freshwater discharges and fisher- 

 men's catch-per-unit of effort. In 

 addition, this data was compared to 

 creel census and pressure esti- 

 mates collected on the river in the 

 late 1950' s to get an idea of some 

 of the long-term effects of the dis- 

 charges . 



The problems involved with the 

 St. Lucie Canal discharges, in con- 

 trast to some Texas estuaries, in- 

 volve the inflow of too much fresh 

 water to the estuarine system. 

 Moderate flows from the St. Lucie 

 Canal structure combined with two 

 agriculture canal releases into the 

 North Fork of the river are a little 

 less than one-half the magnitude of 

 flow into the San Antonio Bay System. 

 However, the St. Lucie measures only 

 one-twentieth the surface area. This 

 imbalance in augmented freshwater in- 

 flow has caused concern about sa- 

 linity structure, sedimentation and 

 associated turbidity. 



Scientific studies aimed at 

 species diversity were concluding 

 that the St. Lucie Canal discharges 

 were either beneficial to the estuary 

 (Gunter and Hall 1963) or that limit- 

 ed discharges had no detrimental 

 effect (Haunert and Startzman 1980). 

 Fishermen and those involved in the 

 tourist trade were not satisfied. 

 Claims were made that the high tur- 

 bidity, resulting from the dis- 

 charges, caused decreases in catch 

 rates, the pushing of sportfishes out 

 of the estuary and a subsequent drop 

 in angler use. 



The Fish and Wildlife Service, 

 under authorization of the Fish and 

 Wildlife Coordination Act and, in 

 conjunction with the ongoing study of 



MATERIALS AND METHODS 



For 13 months, between June 1978 

 and July 1979 , a creel census team 

 systematically surveyed the St. Lucie 

 Estuary system for data concerning 

 the catch of bridge, boat, dock, and 

 wading fishermen. The results of 

 this investigation were correlated 

 with information on freshwater re- 

 leases . 



LIMITATIONS OF FIELDWORK 



It should be noted here that the 

 data collected express conditions dur- 

 ing June 1978 through July 1979. Pre- 

 discharge values are lacking, there- 

 fore, conclusions are based entirely 

 on data collected under the influence 

 of alterations. In addition, all 

 harvest and catch rates have been 

 calculated from interviews performed 

 from sunrise to sunset. Due to man- 

 power limitations and the obvious 

 navigational problems, no sampling 

 was done at night. In addition, to 

 facilitate the systematic sampling 

 necessary for the time series analy- 

 sis, data were collected only on 

 Tuesdays, Thursdays, Saturdays, and 

 Sundays . 



DESIGN CONSIDERATIONS 



The estuary was divided into four 

 zones, each one having demonstrated in 



271 



