There is no evidence that beaches are eroding in areas of artificial or long-stabilized 

 natural foredunes although artificial foredunes have existed for 5 years or less and no severe 

 storm surges have occurred during this time. To the north, the shoreline level on San Jose 

 and Matagorda Islands has prograded seaward (Hunter, et al., 1972). On central and 

 northern Padre Island and on Mustang Island, the shoreline has remained stable for the past 

 century, and probably since the origin of the island (Fisk, 1959; Hunter, et al., 1972). The 

 condition of stability extends to south of Big Shell beach. 



Specific net rates of shoreline change, from surveyed turning points in the middle to late 

 1800's, were presented by Seelig and Sorensen (1973), and were mostly +3 to -3 feet per 

 year for Padre Island north of Mansfield Channel; an exception was a 2-mile-long area 

 around Packery Channel, a hurricane channel complex at the north end of Padre Island, 

 where a former shoreline bulge has eroded 36 feet per year since 1882. The north Padre 

 study site has experienced no net change during the same period. In contrast, the southern 

 part, with no continuous foredune ridge, has experienced shoreline erosion of about 1,000 

 feet in less than a century (Hunter, et al., 1972). Near the south Padre study sites, the 

 shoreline eroded a net average of 10 feet per year since 1880 (Seelig and Sorensen, 1973). 



There is no evidence that a stabilized foredune ridge on Padre or Mustang Island allows 

 succession to salt-intolerant woody plants that are unable to withstand a storm surge flood, 

 as described by Godfrey and Godfrey (1972) for Cape Hatteras, North Carolina. On these 

 islands, woody plants are rare, even leeward of the long stabilized and washover-free Big 

 Shell natural foredunes. The grassland leeward of the foredune ridge is apparently well 

 adapted to recover from saltwater flooding. Mustang Island was flooded by saltwater from 

 the bay during Hurricane Celia which left a drift line on the rear of the foredune ridge. Most 

 of the low back-island was well vegetated before the flood, and was not damaged by wave 

 action or saltwater inundation (McGowen, et al., 1970); the area is still an extensive 

 midheight grassland. However, the unvegetated sandflats in the western part of the island 

 were subjected to severe scouring by the storm surge. 



In summary, the overwash theory of barrier island equilibrium and retreat (Dolan, 

 1972a, b; Godfrey and Godfrey, 1972) does not apply to Mustang Island or the north half 

 of Padre Island. A mostly continuous and well vegetated foredune ridge which minimizes 

 storm surge effects, and a stable shoreline are the natural condition, and none of the events 

 described by these authors for a stabilized foredune system is occurring. 



The present condition on Padre Island south of Big Shell is more similar to the supposed 

 pristine condition of part of the North Carolina Outer Banks, i.e., low, mostly unconnected 

 hummock dunes. Broad overwash (unchanneled) has been shown for the area immediately 

 north of Mansfield Channel (Hayes, 1967). However, even in southern Padre, discontinuous 

 stretches of stablilized foredunes occur. In the extreme southern part, where the island is 

 youngest and generally low and narrow, hurricane washover passes and overwash fans are a 

 dominant feature; between these low areas, a foredune ridge often occurs with associated 

 grassland flats (Fig. 4). 



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