EFFECTS OF TIMBER SIZE-CLASS ON PREDATION OF ARTIFICIAL NESTS IN EXTENSIVE FOREST

Depredation on artificial ground and cup nests in even-aged seedling/s apling, pole, and mature stands of continuous northern hardwood forest was studied in the White Mountain National Forest in New Hampshire, U SA from May to June 1988. Track-board nests were used to identify pred ators of ground nests; plain ground nests and cup nests were used to i nvestigate the effects of timber size-class on rates of predation. No elevation in nest predation rate was observed in the early stages of g rowth, nor was predation rate related to stand area. As elevated preda tion rates are usually taken to indicate the fragmentation of forest, the results of this study suggest that extensive hardwood-dominated fo rests in northern New England are not fragmented by even-aged manageme nt.