EFFECTS OF PRAIRIE FRAGMENTATION ON PREDATION ON ARTIFICIAL NESTS

Predation on nests has been suggested as an important factor limiting nest success of ground-nesting birds in habitat fragments and along habitat edges. We examined predation rates on artificial ground nests (n = 540) in relation to prairie fragment size and proximity to woody cover in 15 remnant, tallgrass prairies (4-571 ha) in southwestern Missouri. Artificial nests in prairies <15 ha (37.0% predation rate) were depredated more than those in larger prairies (13.9%; P < 0.001). Artificial nests <60 m from woody cover (28.7% predation rate) were less successful than were nests farther away (7.9%; P < 0.001). Proximity to woody cover had more influence on artificial-nest success than did tract size when both variates were incorporated in multiple logistic regression and log-linear models. The potential effects of prairie size and woody vegetation on success of ground-nesting birds should be considered in decisions regarding acquisition and management of prairie habitats.