8 2 Craig A. Harper, James F. Parnell, and Eric G. Bolen 



Five baskets were placed over water at no more than 50 cm of depth, and anoth- 

 er five were placed in the adjacent uplands within 15 m of the apparent high- 

 water mark. Mast captured in each basket was identified and weighed in the field 

 to the nearest 0.01 g. The data obtained at each wetland were log 10 transformed 

 because of heterogeneity of variances and were tested by species and location 

 (inside or outside the impoundment) using a one-way ANOVA in the General 

 Linear Models (SAS 1989) procedure. Transformed means were compared 

 using the Student-Newman-Keuls test at the alpha = 0.05 level. 



Macroinvertebrates were sampled in each vegetation plot monthly dur- 

 ing April, May, June, and July 1992, using a plankton tow net and a sweep net. 

 Three water surface samples were obtained with a plankton tow. The water col- 

 umn was sampled with a sweep net by making semicircular sweeps on the left, 

 center, and right side of the plot. An attempt was made to sweep across the entire 

 plot, thus sampling a standardized area. A sweep net also was used to sample the 

 benthos by scraping the substrate with the net across the left, center, and right 

 side of the plot. Samples were preserved in 45% isopropyl alcohol and identi- 

 fied using Thorp and Covich (1991). Specimens were air dried overnight, then 

 ovendried at 55 C for eight hours, and their biomass was determined with a Met- 

 tler electronic balance. Data were log 10 transformed because of heterogeneity 

 of variances and tested for differences in total invertebrate biomass between wet- 

 lands with a one-way ANOVA in the General Linear Models (SAS 1989) proce- 

 dure. Transformed means were contrasted using the Student-Newman-Keuls test 

 at the alpha = 0.05 level. 



Three cypress nest boxes designed for wood ducks were erected at each 

 impoundment upon inundation in October 1990. Each nest box was erected on 

 a steel post equipped with a predator-proof guard and supplied with wood shav- 

 ings. Prior to the 1992 nesting season, sufficient numbers of nest boxes were 

 added to provide one box per 100 m of shoreline at each of the three wetlands, 

 thereby resulting in eight boxes at 1-1, nine at 1-2, and four at 1-3. The boxes 

 were inspected biweekly during May, June, and July and monthly August 

 through April. 



Flush counts were conducted biweekly on the impoundments between 

 September and December 1992. All ducks flushed by an observer walking the 

 perimeter of each wetland were recorded. Brood surveys were conducted each 

 week during May, June, and July 1992 from blinds located at sites arbitrarily 

 selected for their enhanced visibility of shrub-strewn habitat ( Rumble and Flake 

 1982, Robb and Bookhout 1990). Broods were counted for two-hour periods 

 beginning one-half hour before sunrise. Species, brood size, age-class (Gollop 

 and Marshall 1954), and activities were recorded whenever broods were 

 observed. Evening roost censuses were made biweekly between September and 

 December 1992 from suitable vantage points adjacent to each wetland. Sampling 

 effort and number of counts were identical at all impoundments. Flush and roost 



