Publications

No abstract available. 

In this paper, we briefly discuss some of the fundamental problems arising from the inherent complexity of larger-scale ecological systems. We examine the tenuous assumption of a direct correspondence between ecological data and theory, we comment on a recent report that evaluated the efficacy of fragmentation experiments, and we briefly assess its implications for ecological research and conserva

Pastures provide substantial habitat for grassland birds of management concern in the Driftless Area of southwestern Wisconsin. The rolling topography in this region is characterized by lowland valleys surrounded by relatively steep and often wooded slopes which are set apart from more expansive treeless uplands. We hypothesized that there would be lower densities of area sensitive grassland passe

The objective of this study was to determine dietary overlap between blueback herring and threadfin shad in J. Strom Thrumond Reservoir, South Carolina/Georgia. We also evaluated prey selectivity for each speices and diet differences between two size categories of blueback herring. Diet and zooplankton samples were collected every other month from April 1992 to February 1994. We examined stomachs

Various aspects of population structure and dynamics of Eleutherodactylus coqui in two forest reserves (Maricao and Guilarte) of the central mountain range of Puerto Rico were determined between July 1997 and June 1998. Adult density ranged from 8–25 animals/100 m2 for the wet season and 3–19 animals/100 m2 for the dry season. Abundance of froglets and juveniles was also greater in the wet season

No abstract available.

Community convergence across biogeographically distinct regions suggests the existence of key, repeated, evolutionary mechanisms relating community characteristics to the environment. However, convergence studies at the community level often involve only qualitative comparisons of the environment and may fail to identify which environmental variables drive community structure. We tested the hypoth

We determined production and survival of elk (Cervus elaphus nelsoni) calves in Michigan using a variety of methods to index herd productivity. Calf production in Michigan was comparable with the highest rates ever recorded for North American elk. Calf survival averaged 0.90 (SD = 0.05), 0.97 (SD = 0.04) and 0.87 (SD = 0.05) for summer, winter and annually, 1987-1991. Calf survival rates in Michig

Direct approaches for estimating the feeding rate of the opossum shrimp Mysis relicta can be hampered by variable gut residence time (evacuation rate models) and non-linear functional responses (clearance rate models). Bioenergetics modeling provides an alternative method, but the reliability of this approach needs to be evaluated using independent measures of growth and food consumption. In this

We investigated the efficacy of management to reduce the impact of Caspian tern (Sterna caspia) predation on survival of juvenile salmonids (Oncorhynchus spp.) in the Columbia River estuary. Resource managers sought to relocate approximately 9,000 pairs of terns nesting on Rice Island (river km 34) to East Sand Island (river km 8), where terns were expected to prey on fewer juvenile salmonids. Eff

Depleted uranium (DU) has been used as a substitute for the fissionable enriched uranium component of atomic weapons tested at Los Alamos National Laboratory (LANL) (Los Alamos, NM, USA) since the early 1950s, resulting in considerable concentrations of DU in the soils within the test sites. Although the movement of DU into major aquatic systems has been shown to be minimal, there are many small-o

We compared cavity-nesting bird communities in aspen (Populus tremuloides) woodland fragments classified on the basis of vegetation structure (tree density) and landscape context (surrounding vegetation). We found very few cavity nesters in fragments predominantly surrounded by forests. Fragments adjacent to meadows contained more species and a greater abundance of cavity nesters. Species richness