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These figures are from a study of the probabilities of detecting birds at random points in forests of different sizes and degrees of isolation in Maryland.The probabili- ty of detecting a bird at a random point is equivalent to the density of individuals in the forest.The table includes all area- sensitive species breeding in Maryland that also breed in Orange County. COLUMN I shows the area for which the probability of detecting each species is a maximum. It indicates that for many species the density of individuals reaches a maximum only in very large forests. COLUMN 2 shows the area for which the probability of detecting each species is reduced by half. Eight of these species require forests at least 12 hectares (30 acres) in size to have half the maximal densities of individuals. COLUMN 3 provides an indication of the smallest isolated forest in which each species might ever occur. Most forests of these sizes would not have the species. The species with the smallest minimal areas (Tufted Titmouse, Great Crested Flycatcher, Wood Thrush) are ones that sometimes occur in wooded residential areas. Source: Robbins, C. S., D K Dawson, and B.A Dowell (1989). Habitat area requirements of breeding forest birds of the middle Atlantic states.Wildlife Monographs 103: 1 -34. Table THREE MEASURES OF THE SENSITIVITY OF FOREST-NESTING BIRDS TO THE SIZES OF FORESTS Area for which Area for which Median area probability is a probability is of three smallest maximum reduced by 50% forests Louisiana Waterthrush 3000+ 350 24.7 Red- shouldered Hawk 3000 225 40.5 Pileated Woodpecker 3000+ 165 64.3 Summer Tanager 3000+ 40 47.8 Blue -gray Gnatcatcher 3000+ 15 10.1 Acadian Flycatcher 3000+ 15 2.6 Scarlet Tanager 3000+ 12 3.2 Red -eyed Vireo 3000+ 2.5 0.5 Wood Thrush 500 1 0.8 Ovenbird 450 6 1.2 Kentucky Warbler 300 17 10.4 White- breasted Nuthatch 300 3.0 3.0 Hairy Woodpecker 200 6.8 16.1 Red- bellied Woodpecker 85 0.3 1.6 Great Crested Flycatcher 72 0.3 0.8 Tufted Titmouse 52 0.5 0.6 These figures are from a study of the probabilities of detecting birds at random points in forests of different sizes and degrees of isolation in Maryland.The probabili- ty of detecting a bird at a random point is equivalent to the density of individuals in the forest.The table includes all area- sensitive species breeding in Maryland that also breed in Orange County. COLUMN I shows the area for which the probability of detecting each species is a maximum. It indicates that for many species the density of individuals reaches a maximum only in very large forests. COLUMN 2 shows the area for which the probability of detecting each species is reduced by half. Eight of these species require forests at least 12 hectares (30 acres) in size to have half the maximal densities of individuals. COLUMN 3 provides an indication of the smallest isolated forest in which each species might ever occur. Most forests of these sizes would not have the species. The species with the smallest minimal areas (Tufted Titmouse, Great Crested Flycatcher, Wood Thrush) are ones that sometimes occur in wooded residential areas. Source: Robbins, C. S., D K Dawson, and B.A Dowell (1989). Habitat area requirements of breeding forest birds of the middle Atlantic states.Wildlife Monographs 103: 1 -34.