Numerous evergreen trees and shrubs contain labdane acids, including isocupressic acid, which can cause
late-term abortions in cattle. Recent research has shown that the bark from western juniper trees can
also cause late-term abortions in cattle. Additionally, ranchers have observed that cattle in western juniper-infested
rangelands tend to have decreased...
dependence and regulation of relatively large local populations? If so, what are the causative mechanisms and their implications? We conducted an eight-year multigeneration study of population dynamics of bicolor damselfish (Stegastes partitus) inhabiting four large coral reefs in the Bahamas. After a four-year baseline period, it was clear that two...
Forest management problems with even-flow and adjacency considerations are difficult to solve optimally. A heuristic search intensification process, which uses two types of decision procedures, changes to single-decision choices (1-opt moves) and changes to two-decision choices simultaneously (2-opt moves), was used in an attempt to locate feasible and efficient solutions...
The use of a reversion technique during the search process of s-metaheuristics has received little attention with respect to forest management and planning problems. Reversion involves the interruption of the sequence of events that are used to explore the solution space and the re-initiation of the search process from a...
We used spatial optimization to analyze alternative restoration scenarios and quantify tradeoffs for a large, multifaceted restoration program to restore resiliency to forest landscapes in the western US. We specifically examined tradeoffs between provisional ecosystem services, fire protection, and the amelioration of key ecological stressors. The results revealed that attainment...
Many multispecies models have assumed that prey density determines per-capita predator consumption rates, following a functional response relationship. However, empirical evidence suggests that a predator’s diet can also be influenced by a variety of environmental factors, including interactions with other predators. We used diet and abundance data from National Marine...
Climate regime shifts force fish communities through rapid transitions between alternate species assemblages, but little is known about the role that biochemical ecology plays in these transitions. We document a biochemical effect of climate-induced community transitions in boreal oceans: opposite population trajectories of lipid-rich and lipid-poor fish species. We compared...
Determining the causes of vegetation change in arid and semi-arid environments can be difficult and may involve multiple factors, including disturbance, inter-annual climatic variation, soils, effects from years past and interactions between these factors. Theoretical models describing vegetation change in these systems have generally focused on a single aspect as...
Species distribution models (SDMs) are currently being used to identify essential fish habitat and guide
fisheries management worldwide. We present SDMs based on generalized linear mixed models (GLMM) of
the fall distribution or occurrence of juvenile American shad (Alosa sapidissima) and juvenile striped bass
(Morone saxatilis) in the Hudson River...
Despite the importance of habitat in determining species distribution and persistence, habitat dynamics are rarely modeled in studies of metapopulations. We used an integrated habitat-occupancy model to simultaneously quantify habitat change, site fidelity, and local colonization and extinction rates for larvae of a suite of Great Plains stream fishes in...