Recovery Plan for the Northern Spotted Owl - DRAFT

Nonmarket - products derived from resources that do not have a well-establishedmarket value: for example, recreation, wilderness, wildlife. RGOccupancy rate - in reference to spotted owls, the percent of inventoriedspotted owl habitat that is estimated to be occupied by breeding pairs ofspotted owls.Off-road vehicles (ORVs) - vehicles such as motorcycles, all-terrain vehicles,four-wheel drive vehicles, and snowmobiles. RGOld-growth - a forest stand with moderate to high canopy closure; a multilayered,multispecies canopy dominated by large overstory trees; a highincidence of large trees with large, broken tops, and other indications ofdecadence; numerous large snags; and heavy accumulations of logs andother woody debris on the ground.Old-growth species - plant and animal species that exhibit a strong associationwith old-growth forests.Old-growth stand - a mappable area of old-growth forest.Oregon-Washington Interagency Wildlife Committee - a committee composedof administrators from federal and state agencies; including theU.S. Forest Service, the U.S. Fish and Wildlife Service, U.S. Bureau ofLand Management, the Oregon Department of Fish and Wildlife, and theWashington Department of Game.Overstory - trees that provide the uppermost layer of foliage in a forest withmore than one roughly horizontal layer of foliage.Owl site - any site where there has been a recent or historic observation of asingle spotted owl or a pair of owls.Pair site - an amount of habitat that is considered capable of supporting onepair of spotted owls.Phenology - the annual recurrence of plant and animal phenomena that isinfluenced by seasonal and other environmental changes, e.g., floweringof plants, ripening of fruit.Physiographic province - a geographic region in which climate and geologyhave given rise to a distinct array of landforms. Biology and habitatrelationships of spotted owls vary by physiographic province due todifferences in climate, vegetation, and productivity of habitats.Platform nest - a relatively flat nest constructed on a supporting structuresuch as a broad branch.Population density - number of individuals of a species per unit area.Population dynamics - the aggregate of changes that occur during the life of apopulation. Included are all phases of recruitment and growth, senility,mortality, seasonal fluctuation in biomass, and persistence of each yearclass and its relative dominance, as well as the effects that any or all ofthese factors exert on the population. SAFPopulation viability - probability that a population will persist for a specifiedperiod of time across its range despite normal fluctuations in populationand environmental conditions.655