Grantee Research Project Results
Black Skimmers (Rynchops niger) in an Urban Landscape: Contaminant and Diet Influences on Reproductive Output in San Diego BayEPA Grant Number: FP917486
Title: Black Skimmers (Rynchops niger) in an Urban Landscape: Contaminant and Diet Influences on Reproductive Output in San Diego Bay
Investigators: Millow, Christopher J
Institution: San Diego State University
EPA Project Officer: Cobbs-Green, Gladys M.
Project Period: August 20, 2012 through August 19, 2015
Project Amount: $84,000
RFA: STAR Graduate Fellowships (2012)
Research Category: Academic Fellowships , Fellowship - Ecology
The goal of this research is to investigate contaminant exposure in Black Skimmers and explore associations with diet and reproductive output. Specifically, the research aims to: (1) quantify nontargeted and targeted contaminants present in egg homogenate and blood plasma; (2) evaluate relationships between contaminant loads and egg viability; and (3) determine if a relationship exists between adult diet and egg contaminants.Approach:
To address objectives (1) and (2), egg and plasma will be liquid-liquid extracted, spiked with reference standards and cleaned of lipids by gel permeation chromatography (GPC) and Solid Phase Extraction (SPE). Nitrogen-evaporated extracts will be analyzed by a novel comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GCÃ—GC/TOF-MS). Acquired mass spectra of contaminants will be library-referenced, visually examined and quantified against standard curves. To address objective (3), carbon and nitrogen stable isotope values of eggshell membranes (indicative of adult diet at time of egg formation) will be compared with contaminants found within egg homogenate.Expected Results:
The project addresses an applied ecological question through interdisciplinary and innovative analytical methods. By combining stable isotope and contaminant analyses, this project will provide a comprehensive perspective of how contaminants and diet vary within an organism believed to exhibit high levels of environmental contaminants. Limited studies connect bioaccumulative contaminant impacts with the productivity of an organism. Using a novel analytical approach, the study will evaluate relationships between targeted and nontargeted compounds and reproductive output. Results from this research will provide a comprehensive inventory of both known and previously unknown chemical compounds in southern California’s coastal waters, using the Black Skimmer as an upper-level environmental sentinel.
Potential to Further Environmental/Human Health Protection
Emerging from this research will be a comprehensive inventory of both known and previously unknown chemical compounds in southern California’s coastal waters, subsequently aiding in the assessment of environmental exposure to a wide range of contaminants. From a human health perspective, chemicals detected in marine species inform of contamination risks to the high density human populations along southern California’s urbanized and industrialized coastline. From here, contaminant sources can be traced and existing and/or new regulatory policies can be strengthened. This research also will provide a novel methodological framework for analyzing contaminants in seabird tissues.Supplemental Keywords:
persistent organic pollutants, seabirds, stable isotopes