Effects of Management Strategies on the Reproductive Success of Least Terns on Dredge Spoil in Georgia

Sterna antillarum antillarum (Eastern Least Tern) historically nested on Atlantic Coast beaches and barrier island shores, but has moved inland to artificial habitats, such as dredge-spoil sites, as available natural habitat has been lost to development and increased human recreational activities. Least Terns readily nest on artificial sites, but the effects of different habitat characteristics and depredation conditions on reproductive success are unclear. We examined the effects of management strategies, disking and electric fencing, on daily survival rate (DSR) and 21-day survival rate (DSR21) of clutches, and on apparent nesting success on a dredge-spoil site in Georgia from 1993 through 1998. All 3 estimates of reproductive success increased as management intensity increased. Significantly (χ22 = 185.8, P < 0.001), DSR increased from 0.88 (1993, no management) to 0.97 (1998, disking in March to remove vegetation and enclosure with an electric fence). Corresponding DSR21 were 0.06 and 0.59, respectively. Artificial nesting sites can be improved by management actions, and such work may be increasingly important as natural habitat for beach-nesting birds continues to decline in availability and quality.