separated from each other and the large stream by slight 

 elevations. . .. As a rule, the bottoms of these small 

 bodies of water are firm, but a few of those nearest the 

 river an decidedly bogg)i. On each side of the river, and 

 between the water and the grass-covered land, is a space 

 perhaps twenty yards in width, which is made up of 

 bottomless mud To venture on to this mud is simply to 

 venture into it, and as it is seemingly without limit in 

 depth, one might better try to walk on the ocean, so far 

 as danger is concerned 



"We found wild geese and ducks in abundance; nearly 

 every one of these small ponds was well stocked with 

 them.... Gulls and terns were also plentiful. . .. These 

 birds frequent the place in search of food, which they 

 find about the strip of mud next the river. " (Peirce 

 1894). 



From Peirce's description, the north bank of the 

 Nueces River within the delta was very low. At 

 present, the river bank in the upper delta is about 

 1.5 to 2.1 m (5 to 7 ft) above that of the elevation of 

 the river under low flow conditions. Several factors 

 could have contributed to this change, including river 

 channelization and the intentional deposit of fill 

 material. Evidence of the later, in the form of 

 scattered concrete rubble and re-bar, was found by 

 Reclamation during construction of the Nueces 

 Overflow Channel (Figure 2-11). 



Given the lower flooding threshold for delta 

 inundations and the expanse and condition of the 

 described mudflats adjacent to the river, the occurrence 

 of freshets into the delta from the Nueces River were 

 likely much more common at the turn of the century 

 than at present. However, as can be observed today, 

 the Nueces River in the delta was not continually fresh, 

 as Peirce testifies that, 'ihe water of the river was not strong 

 of salt, but was just brackish enough to fail completely to quench 

 thirst" (18,94). That the Nueces River frequendy 

 experienced dry or low-flow periods prior to 1900 was 

 also observed by others (Hollon 1956; Collins 1878). 



Other evidence that the delta was much fresher than 

 at present is the presence of Rangia middens 

 (Figure 2-12). These piles of bivalve shells are the 



Figure 2-1 1 : Example of concrete rubble found at 

 several points along the north bank of the Nueces 

 River downstream from the IH 37 bridge. It is 



speculated that this material was intentionally placed in 

 low portions of the bank to reduce flooding of adjacent 

 pastures and was probably acquired from the highway 

 bridge renovation during the late 1950's. 



Photo courtesy of U.S. Bureau of Reclamation. 



remains of foraging activities by Native Americans and 

 may be found in the Nueces Delta at several locations 

 along Rincon Bayou. Rangia cuneata is the dominant 

 animal in Gulf coast estuaries where salinity 

 concentrations continuously range from to 1 5 ppt 

 (Hopkins et al. 1973). Although adults can sur\ave 

 higher salinity values, lan^ae require concentrations in 

 the range of 2 to 10 ppt for survival. The presence of 

 large adult Bjingia in the Nueces Delta indicates that the 

 habitat there had been primarily oligohaline. At 

 present, adult Rangia are only found only in the Nueces 

 River just below die Calallen Dam (Kalke 2000). 



Several weeks later, Peirce and his guide made a second 

 excursion, only this time they ventured into the delta 

 by boat from Nueces Bay: 



2-12 ♦ Study Area 



