the early defoliation, but visual evidence 

 pointed to thorough flushing of stored 

 detritus froui the swamp floor which would 

 not wash out under nonnal weather 

 conditions . 



On the other hand, a survey of salt 

 marsh biomass in the Barataria and 

 Terrebonne basins in progress at the time 

 of the same hurricane (Gosselink et al . 

 1977) showed no evidence that dead biomass 

 collected from the marsh surface was any 

 different in plots sampled before the 

 hurricane than after. 



Short-term effects of Hurricane 

 Camille on species composition in fresh 

 and brackish marshes near the mouth of the 

 Mississippi River were described by 

 Chabreck and Palmisano (1973). They found 

 that an increase in salinity caused by the 

 hurricane tide was ephemeral. The major 

 effect seened to be widespread destruction 

 of vegetation, especially woody species, 

 by wind and water which uprooted and 

 ripped apart stands of plants. Recovery 

 of most species was rapid so that prehur- 

 ricane levels of abundance were approached 

 within a year. In the small lakes and 

 ponds, however, the submerged and floating 

 vegetation was slow to recover. 



Probably the most dramatic alteration 

 documented in marshes is that described by 

 Valentine (1977) in the chenier plain of 

 southwestern Louisiana. One hundred sixty 

 thousand ha of CI adium jamai cense 

 (sawgrass) were killed by the saline tide 

 of Hurricane Audrey in 1957. The 

 following year 86 percent of this area was 

 open water. During the drought years of 

 the early 50' s annual grasses and sedges 

 became abundant. By 1972 Sagittaria 

 falcata (bulltongue) occupied 74 percent 

 of the area and Nymphaea odorata (white 

 water-lily) 11 percent. C_. jamaicense 

 never reestablished itself in any 

 extensive areas, oerhaps because seed 

 viability was very low. Secondary effects 

 of these vegetation changes on duck 

 feeding habits were dramatic. Prior to 

 1959 C^. jamaicense seeds were an 

 important component of duck diets. In the 

 years immediately following the hurricane, 

 duck stomachs contained primarily rice 

 seeds, indicating heavy dependence on 

 agricultural areas outside the marshes. 

 During succeeding drought years, when the 

 marshes produced large quantities of 

 annual grass seeds, large numbers of both 

 ducks and geese were attracted to these 

 habitats. It seems likely, therefore, 

 that hurricanes are major forces on gulf 

 coast marshes, initiating changes that can 

 have significant consequences for years 

 following the storm. 



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