Sex ratio of Western Bluebirds is mediated by phenology and clutch size.

Mothers may produce more of one sex to maximize their fitness if there are differences in the cost of producing each sex or there are differences in their relative reproductive value. Breeding date and clutch size are known to influence offspring sex ratios in birds through sex differences in dispersal, social behaviours, differential mortality, and available food resources. We tested if breeding date, clutch size and drought conditions influenced offspring sex ratios in a sexually size-monomorphic species, the Western Bluebird, by interrogating a 21-year dataset.

Natural attenuation of coal combustion waste in river sediments.

The weathering of coal combustion products (CCPs) in a lotic environment was assessed following the Tennessee Valley Authority (Kingston, TN) fly ash release of 2008 into surrounding rivers. Sampled materials included stockpiled ash and sediment collected from 180 to 880 days following the release. Total recoverable concentrations of heavy metals and metalloids in sediment were measured, and percent ash was estimated visually or quantified by particle counts.

Using artificial burrows to evaluate inhalation risks to burrowing mammals.

Since the onset of plutonium production at the U.S. Department of Energy's Hanford Site, several hundred cubic meters of carbon tetrachloride (CCl4) has been discharged to the soil column, resulting in a dispersed CCI4 vapor plume in the subsurface.

Wildlife ecological screening levels for inhalation of volatile organic chemicals.

For most chemicals, evaluation of ecological risk typically does not address inhalation because ingestion dominates exposure. However, burrowing ecological receptors have an increased exposure potential from inhalation at sites contaminated with volatile chemicals in the subsurface. Evaluation of ecological risk from contaminants like volatile organic chemicals (VOCs) is constrained by a lack of relevant ecological screening levels (ESLs).

Investigations of contaminated fluvial sediment deposits: merging of statistical and geomorphic approaches.

Concentrations of contaminants in sediment deposits can have large spatial variability resulting from geomorphic processes acting over long time periods. Thus, systematic (e.g.