maintenance. After the hurricane, the amount of fill needed to meet 

 the specifications increased substantially. 



A study of the benthic macrofauna on the beach and the nearshore 

 zone of the Gulf of Mexico off Panama City Beach had been underway for 

 11 months before the storm. When notified of the possibility of the 

 storm's arrival at Panama City Beach, special benthic sampling was 

 initiated in the swash zone 1 day before (22 September 1975) the 

 storm. Sampling continued on the day after the storm and on a 

 decreasing frequency for 28 days. 



This part of the report presents the findings on the number of 

 species and individuals, diversity index, and number of individuals 

 per unit area in the swash zone on Panama City Beach, Florida, before 

 and after Hurricane Eloise. 



2. Methods . 



The sampling methods and the gear used are the same as previously 

 described. The only exception was that eight plug samples were taken 

 at each site instead of four, and the samples were not subdivided into 

 top and bottom parts. 



3. Results. 



a. Sediments . Samples for sediment analysis were not collected 

 for this special study; however, surface sediments had been collected 

 monthly for 11 months before the hurricane at the same nine sites. 



b. Hydrology . Water temperature and salinity in the sampling area 

 did not change substantially after the hurricane. Total rainfall 

 associated with the storm was only 0.66 inch (1.7 centimeters). Water 

 temperatures decreased, and salinities increased slightly (Table 31) . 

 Due to the lack of substantial changes in water temperature and 

 salinity, the influence of these two factors on the abundance and 

 diversity of the benthic macro invertebrates was negligible. 



c. Macrofauna . Benthic macrofauna collections were made on 8 

 separate days, 1 day before the storm and 7 different days after. The 

 dates were 22, 24, 25, 26, and 29 September, 2, 7, and 21 October 1975. 



The number of individuals gradually increased from 465 at the nine 

 stations on the first day after the storm to a high of 1,358 individ- 

 uals 6 days after the storm; 9 days after the storm, the number of 

 individuals decreased and continued dropping through the last sampling 

 date (Table 32) . The number of species caught at the nine sites nearly 

 doubled the day following the storm and remained high for 6 days after 



105 



