Question: Are there general life-history rules for exploitation-caused extinction of mammal populations?
Mathematical methods: A population of size N faced with the added mortality of human exploitation will deterministically go extinct if its per-capita birth rate can no longer match its per-capita mortality rate as N approaches zero. We develop...
This article concerns a systemic manifestation of small scale interfacial heterogeneities in large scale quantities of interest to a variety of diverse applications spanning the earth, biological and ecological sciences. Beginning with formulations in terms of partial differential equations governing the conservative, advective-dispersive transport of mass concentrations in divergence form,...
"After a brief description of the setting of the Yaquina Estuary, estuarine dynamics and classification, and estuarine chemistry are presented. Then, temperature-salinity relations are reviewed using the Rattray-Officer model in simulating variable distributions reported by Callaway and Specht (1982) and Callaway (1991). Finally, the numerical models DynHyd and WASP are...
This report discusses data collected in the Yaquina Estuary from July 1976 through December 1977 at 6-8 week intervals. Also summarized are recording salinometer, runoff and precipitation data from September 1967 through July 1968. Station names and locations for the 76-77 field data are shown in Figure 1. Figure 2...
Measurements of physical tree crown dimensions were of subjective character in the past, even though they can be considered important for the management of many silvicultural operations, such as timing of thinning operations. In our study we investigated if and how measures of physical crown dimensions of trees differed when...
Managing rangelands with livestock grazing is a tool that can be applied to obtain vegetation management objectives. Animals utilize available resources, which vary in quantity and quality, across the landscape. Their movements are adjusted to the spatial and temporal heterogeneity of resource distribution. Controlling livestock distribution is fundamental to economically...
Landscape models for elk distribution developed at Starkey Experimental Forest and Range from 1993-1995 were tested on another landscape during 2003-2005 at Sled Springs Wildlife Demonstration Area. Using location data obtained from 23 wild elk captured and fitted with GPS telemetry collars, 8 spatial resource selection function models representing 8...