if this is occurring. Vegetative data obtained from the transects are used in this evaluation. A 

 numerical prevalence index (P.I.) can be used to assess changes that occur to the vegetative 

 community. 



To find the P.I., an indicator value is assigned to each plant species recorded for a particular site 

 based on its tolerance to salinity (Table 1). For example, Distichlis spicata prefers an average 

 salinity of 13.0 ppt for optimum growth; therefore, this species will be assigned an indicator value 

 of 1. 



Table 1. Indicator values with their corresponding salinity and 

 marsh types. 



Indicator value 



Average salinity (ppt) 



Marsh type 



1 

 2 

 3 



4 



Each plant species found on a transect is assigned an indicator value. The values of all plants 

 recorded are added and then divided by the total amount of occurrence to find the average P.I. 

 of a site. 



Hunting and Trapping 



The number of waterfowl, deer, furbearers, and alligators harvested from the management area 

 are monitored by TLT. The area is leased to a limited number of individuals for hunting and 

 trapping. Records are kept on the amount of wildlife removed from the management area. 



RESULTS 



Changes in the land:water ratio for these five years of data are displayed in Table 2. 



Table 2. Historical change in ratio of land to open water (in hectares) 

 at Tenneco-LaTerre mitigation area, Terrebonne Parish, LA. 



Year 



Land 



Water 



a 1986 photo showed no distinguishable difference from 1985. 



325 



