Publications

The One Health initiative is a global effort fostering interdisciplinary collaborations to address challenges in human, animal, and environmental health. While One Health has received considerable press, its benefits remain unclear because its effects have not been quantitatively described. We systematically surveyed the published literature and used social network analysis to measure

Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total...

The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average...

In birds where males and females are similar in size and plumage, sex determination by alternative means is necessary. Discriminant function analysis based on external morphometrics was used to distinguish males from females in two closely related species: Western Grebe (Aechmophorus occidentalis) and Clark's Grebe (A. clarkii). Additionally, discriminant function analysis was used to...

Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using...

Sediment-toxicity benchmarks are needed to interpret the biological significance of currently used pesticides detected in whole sediments. Two types of freshwater sediment benchmarks for pesticides were developed using spiked-sediment bioassay (SSB) data from the literature. These benchmarks can be used to interpret sediment-toxicity data or to assess the potential toxicity of pesticides...

In egg contaminant studies, it is necessary to calculate egg contaminant concentrations on a fresh wet weight basis and this requires accurate estimates of egg density and egg volume. We show that the inclusion or exclusion of the eggshell can influence egg contaminant concentrations, and we provide estimates of egg density (both with and without the eggshell) and egg-shape coefficients...

Most of the known wintering areas of Piping Plovers (Charadrius melodus) are along the Atlantic and Gulf coasts of the United States and into Mexico, and in the Caribbean. However, 1066 threatened/endangered Piping Plovers were recently found wintering in The Bahamas, an area not previously known to be important for the species. Although representing about 27% of the birds counted during...

We conducted a detailed assessment of the maternal transfer of mercury and selenium to eggs in three bird species (n = 107 parents and n = 339 eggs), and developed predictive equations linking contaminant concentrations in eggs to those in six tissues of the mother (blood, muscle, liver, kidney, breast feathers, and head feathers). Mercury concentrations in eggs were positively...

Mercury (Hg) emission and deposition can occur to and from soils, and are an important component of the global atmospheric Hg budget. This paper focuses on synthesizing existing surface-air Hg flux data collected throughout the Western North American region and is part of a series of geographically focused Hg synthesis projects. A database of existing Hg flux data collected using the...

Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed...

Diamondback terrapins (Malaclemys terrapin) are currently in decline across much of their historical range, and demographic data on a regional scale are needed to identify where their populations are at greatest risk. Because terrapins residing in salt marshes are difficult to capture, we designed a cylindrical bait trap (CBT) that could be deployed in shallow tidal waters. From 2003 to...