In this report forests are presented as very dynamic ecosystems, and processes such as nutrient cycling, nitrogen saturation, sedimentation, erosion, and forest fragmentation are described. Ecological processes, such as disturbance and succession, are described in relation to forest management. Ecological and economic values and their societal implications are compared. Alternatives to...
A juvenile Marbled Murrelet (Brachyramphus marmoratus) sits on its nest platform high in an old-growth Douglas fir. The Marbled Murrelet is an endangered seabird. A recent study used age-ratio analysis of museum specimens collected from 1892-1922 to measure long-term demographic changes in this species. Researchers compared the long-term demography with contemporary estimates and predictions from...
An adult male valley elderberry longhorn beetle (Desmocerus californicus dimorphus) perches on a leaf of its host plant, blue elderberry (Sambucus mexicana). Although classic metapopulations are thought to be uncommon in nature, this rare beetle displays characteristics of such a population dynamic: low local densities, discrete habitat patches, limited movements, and a strongly influenced of...
The southern torrent salamander (Rhyacotriton variegatus) inhabits small, cool, headwater streams and seeps in conifer-dominated forests, primarily in the Coast Ranges of Oregon and northern California. Research in the Oregon Coast Range suggests that maintaining forested habitat >46 m around these streams is important if the protection of habitat for this and other headwater-associated amphibians...
The Bearded Vulture (Gypaetus barbatus) is a threatened species. Many conservation programs aim to increase population size by improving survival and reproduction; however, density dependence may confound this approach. A recent study evaluated the consequences of population growth on reproductive performance of Bearded Vultures in the Spanish Pyrenees, and its results suggest that the use of...
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