GSA Annual Meeting in Denver, Colorado, USA - 2016

Paper No. 321-25
Presentation Time: 9:00 AM-6:30 PM

A HISTORICAL ANALYSIS OF MERCURY IN RED-TAILED HAWKS (BUTEO JAMAICENSIS) IN THE PACIFIC NORTHWEST


ULBRICHT, Lauren K., Geology, University of Puget Sound, 4433 Wheelock Student Center, Tacoma, WA 98416, lk.ulbricht@frontier.com

Mercury is a potent neurotoxin and has impacts on the reading success and survival of wildlife. Many recent studies show high or increasing mercury levels in marine and arctic species – these are attributed to increased coal combustion in China. To what extent do terrestrial species reflect the increases seen in marine species? To answer this question we examined total mercury (tHg) and carbon and nitrogen stable isotopes in feathers from Red-tailed Hawk museum specimens from Washington and Oregon collected over the last century. We predicted higher mercury levels in recent specimens and in specimens from west of the Cascades because of higher precipitation, thus deposition. Preliminary results indicate a slight increase in tHg since 2000, but no difference between western and eastern birds. There appeared to be no correlation between nitrogen isotope ratio (use the symbol for that) and tHg, but there was a significant decline in carbon isotope ratio (use symbol) over the past century reflecting the increase in atmospheric CO2.