PRODUCTIVITY OF THE SPRUCE GROUSE AT THE SOUTHEASTERN LIMIT OF ITS RANGE

We measured productivity of the Spruce Grouse (Dendragapus canadensis canadensis) in patchy black spruce (Picea mariana) habitat along the s outheastern limit of its range in mid-coastal Maine. We captured grous e and attached necklace-mounted radio transmitters to hens prior to ne sting. Of 19 females monitored, only 26% raised chicks to the late bro od-rearing period. Predation was high on hens (37%) and five were kill ed before hatching eggs. Six (55%) entire broods were lost and only 30 % of chicks survived to late summer. Production (No. of chicks/female) , an index of productivity was <1 and lower in Maine and Minnesota stu dy areas in black spruce than areas dominated by jack pine (Pinus bank siana) or a mixture of jack pine and spruce with dense undergrowth. Wh ere Spruce Grouse breed in patchy black spruce communities, immigratio n from neighboring populations or inter-patch movement by local indivi duals may be required to maintain viable populations.