Publication Date

12-2013

Date of Final Oral Examination (Defense)

10-11-2013

Type of Culminating Activity

Thesis - Boise State University Access Only

Degree Title

Master of Science in Raptor Biology

Department

Biology

Major Advisor

Jennifer Forbey, Ph.D.

Advisor

Kim Fernie, Ph.D.

Advisor

Julie Heath, Ph.D.

Advisor

Alfred M. Dufty, Jr.

Abstract

Two major goals in the field of toxicology are to determine the bioavailability and effects of contaminants, like antimicrobials, that are becoming more abundant and thus more of a concern for biota and the environment. Despite the implications of elevated concentrations of antimicrobials in urban ecosystems, few studies have addressed the bioavailability and consequences of these contaminants at higher trophic levels. Triclocarban (TCC) and triclosan (TCS) are two of the most utilized antimicrobial compounds in the world and they can be introduced into ecosystems through a variety of sources including the application of biosolids to agricultural fields. I hypothesized that antimicrobials found in biosolids would be bioavailable and would negatively impact birds. To test these hypotheses, I compared the transfer of antimicrobials in land-applied biosolid, soil, worms, small mammals, and eggs of two bird species between an Experimental (biosolid applied over a seven year period) and Reference (no application of biosolid) agricultural site. I also tested the impact of antimicrobials on egg morphometrics (egg length, egg mass, and egg shell thickness) and nesting success of birds. I used Liquid Chromatography – Mass Spectrometry to quantify the concentration of antimicrobials in biosolid, soil, earthworms, small mammals, and eggs of the American kestrel (Falco sparverius) and the European starling (Sturnus vulgaris). Antimicrobials were significantly higher in soil, earthworms, small mammal tissue, and eggs of starlings on the Experimental site compared to the Reference site. Concentrations of antimicrobials in the eggs of kestrels did not differ between the Reference and Experimental site, however there was no correlation between antimicrobial concentrations and egg morphometrics for either bird species. Nesting success for kestrels was significantly lower on the Experimental site than the Reference site, whereas nesting success of starlings did not differ between sites. This study demonstrated that antimicrobials from biosolids can be transferred to eggs of secondary and tertiary consumers and contaminants from biosolids should be further investigated as a potential factor influencing the nesting success of birds.

Share

COinS