FIGURES (Continued) 

 Number Page 



3-26 Relationship between menhaden catch and fishing effort. Estimated average maximum 



sustainable yield is 478,000 tonnes 84 



3-27 Inshore and offshore commercial landings of white shrimp in Louisiana by hydrologic unit 85 



3-28 Inshore and offshore commercial landings of brown shrimp in Louisiana by hydrologic unit 86 



3-29 Fishing areas for industrial bottom fish along the northern Gulf coast 87 



3-30 Supply of and demand for saltwater fishing and sporthunting by basin, in the Chenier 



Plain, excluding the Nearshore Gulf Habitat 90 



3-31 The relationship between the areal waterload (qs) and phosphorus retention (Rp) in 

 fifteen southern Ontario lakes, from Kirchner and DiUion (1975) as shown in Craig 

 etal.(1979) 92 



3-32 Hydrologic regions of the Vermihon, Mermentau, and Chenier basins 96 



3-33 Freshwater supply of Vemiihon Basin: (A) riverine input from U.S. Geological Survey 

 discharge data; (B) mean monthly water surplus (deficit); (C) monthly water surplus 

 deficit in a dry year; and (D) monthly water surplus (deficit) in a wet year. Calculated 

 from U.S. Weather Service data as described by Borengasser 1977 102 



3-34 Water levels in Vemiilion Basin; (A) Surface water slopes; (B) monthly variation in daily 

 tidal range; (C) seasonal variation in mean water level; (D) long-term annual mean water 

 level 103 



3-35 Monthly means and standard deviations (1948-1974) of Vermilion Lock from U.S. Army 



Corps of Engineers records 104 



3-36 Yearly means and standard deviations (1947-1974) of chlorinity at the Vermihon Lock, 

 from U.S. Army Corps Engineers records. The regression coefficient is significant 

 (P <.05) 104 



3-37 Freshwater supply of Mermentau Basin: (A) riverine input from U.S. Geological Survey 

 discharge data; (B) mean monthly water surplus (deficit); (C) montWy water surplus 

 (deficit) in a dry year; and (D) monthly water surplus (deficit) in a wet year. Calculated 

 from U.S. Weather Service data, as described by Borengasser 1977 106 



3-38 Water levels in Mennentau Basin: (A) surface water slopes in the Memientau and Chenier 

 basins, from U.S. Army Corps of Engineers gages; (B) monthly variation in daily tidal 

 range ; (C) seasonal variation in water level at Lacassine ; and (D) long-term mean annual 

 water level 107 



3-39 Monthly means and standard deviations (1947 to 1974) of chlorinity in the Mermentau Basin 



inside Catfish Point control structure, from U.S. Army Corps of Engineers records 108 



3-40 Monthly mean water levels above mean sea level (MSL) inside and outside the Freshwater 



Bayou control structure (1963-1974), from U.S. Army Corps of Engineers gages 113 



341 Water levels in Chenier Basin; (A) surface water slope in the Chenier and Mermentau basins 



from U.S. Amiy Corps of Engineers data;(B) monthly variation in daily tidal range at Grand 



Chenier; (C) seasonal variation in water level in Grand Chenier over a year; and (D) typical 



tide record 119 



342 Hydrologic regions of Calcasieu Basin 121 



343 Freshwater supply of Calcasieu Basin: (A) mean monthly freshwater discharge and salinity;(B) 



mean monthly rainfall surplus; (C) monthly rainfall surplus for a dry year; and (D) monthly 



rainfall surplus for a wet year 1 26 



344 Water levels in Calcasieu Basin: (A) surface water slope; (B) 1971 monthly variation in the 



semidiurnal tidal range at Cameron; (C) seasonal variation in water level at Cameron (1963- 



1974); (D) long-temT annual mean water level; and (E) typical tide records. From U.S. Army 



Corps Engineers gage records 127 



345 Mean annual salinities at Lake Charles, Louisiana (1956-1975) from U.S. Army Corps of 



Engineers data 128 



346 Commercial landings of brown and wlute shrimp in the Calcasieu Basin in 1963-1975 128 



347 Hydrologic regions of Sabine Basin 130 



348 Freshwater supply of Sabine Basin: (A) discharges from Sabine River into Sabine Basin, 



comparing the mean for two years before 1968 with the mean for seven years after 

 1968, from U.S. Army Corps of Engineers gages; (B) mean (1964-1973) montlily rain- 

 fall surpluses (deficits); (C) montlily rainfall surplus (deficit) for a dry year; and (D) 

 monthly rainfall surplus (deficit) for a wet year 136 



349 Water levels in Sabine Basin: (A) surface water slope; (B) monthly variation in daily 



tidal range; (C) seasonal variation in daily tidal range; (D) typical tide record. 



From U.S. Army Corps of Engineers gage records 137 



3-50 Maximum and minimum sahnity (°/oo) in Sabine Lake when the Sabine River flow was 



low in March 1968 and when it was high in July 1968 138 



