This year I was supposed to be taking a summer off from fieldwork to get a bunch of lab work and writing done.... But like any good field biologist, I just couldn't handle missing an entire breeding season and instead decided to do a small field run in Olympic National Park. With help with my advisor and BRI, I somehow managed to both convince and fund Dr. Rebecka "I think we just became best friends" Brasso to come help me. Rebecka is starting her first faculty job at SE Missouri State this fall and had some free time this summer. And like any good field biologist, she thought "free time" was best filled with 4am wakeup calls, heavy packs, long hikes and peanut butter and jelly sandwiches. We had two weeks of rain-free glorious weather and got to see a lot of cool birds. I am so grateful for her help and excited to see what our results show! More on that later - but enjoy the photo gallery below with the important and memorable parts of our trip.
On an afternoon off, I made Rebecka go with me to see the Elwha Dam... or lack thereof. They recently removed the dam here to allow salmon passage and it was really cool to see the man-made reservoir reverting back to its original river. Even Dr. Brasso agreed (although on the drive might have thought I was crazy)
I enjoyed field work with Allyson and the rest of the crew so much that I decided to take advantage of the opportunity to work on a part of her project involving feathers! Katie, my fellow undergraduate research assistant, and I are both investigating Hg levels in feathers of our ‘dead bird’ collection which have been painstakingly plucked and organized by Colleen and helpers. These birds come from a variety of sources, with the majority either found and delivered to us or sent from Chintimini Wildlife Center when the birds don’t survive.
My little project within Allyson’s enormous project is looking at primary feathers of thrushes (and hopefully other families next term) and their Hg levels. The question that I would ideally be able to answer by the end is whether total Hg in adult primary feathers is dependent on their molt pattern in the American Robin, Varied Thrush, Hermit Thrush, and Swainson's Thrush. One challenge I have discovered in my literature search is the lack of dependability on feathers as an Hg indicator. This is one of the main reasons I chose to do this project, to see if certain feathers can be more reliable or give us more information than others. There is some discrepancy over the correct unit to use when trying to quantify mercury in a feather. Most research utilizes ppm of Hg as their measurement, but one paper, Bortolotti 2010, claims that using a unit of Hg mass (ng)/feather length (mm) is the appropriate unit since Hg is deposited in the feather according to abundance of Hg in blood at the time of growth. I’m hoping that the results I get from this term and next term will begin to shed some light on which unit makes sense to use for mercury and why.
To do this, I measured feather length and prepped the left and right primaries for these species (12 birds total) to get run through the lab’s mercury analyzer. I currently have the data from the left primaries for the thrushes and am attempting to form my next steps in this project.
Both graphs show the quantity of Hg in each primary feather (average of all 12 birds). The first graph is in ppm Hg while the second is in Hg (ng)/feather length (mm). They both show the same pattern with increasing primary feather number. This may indicate that either unit may be appropriate to quantify Hg levels in feathers.
Bortolotti GR (2010) Flaws and pitfalls in the chemical analysis of feathers: bad news-good news for avian chemoecology and toxicology. Ecol Appl 20:1766–1774
This was a very busy winter and spring for me! I passed my comprehensive exam in March, which means that I'm now a PhD candidate. Those of you who haven't gone through it probably don't think that sounds all that fancy (I agree) and those that have been through it probably still have scary stress dreams about the whole process. I can say the preparation and exam was a completely humbling experience - realizing how much I don't know and how little my brain is capable of absorbing, even when I've been cultivating this mental muscle for so many years. All I can say with certainty is that I'm very glad it's over!
After my exam, I jumped (unfortunately) into a busy spring term of teaching a new class (Field Sampling in Fisheries and Wildlife), finishing my final two teaching courses, and advising two undergraduate research students, all while trying to apply for an EPA STAR fellowship again and analyze data for my dissertation. I have to say the best part of the term was working with the undergrads! Danielle and Katie both made my job easy! Even in my busy and frantic state, both students came up with really interesting projects on their own based around our "dead bird project" (terrible name which has apparently stuck). This project has grown from our collective curiosity about what mercury concentrations in feathers mean for songbirds. In seabirds, many researchers use feathers as a proxy for body burden of mercury, but no one has tested whether this also applies to songbirds. Working with a variety of collaborators, we have acquired specimens of songbirds where we can sample all feathers to see how feather tracts compare in mercury concentrations (something we can't do in live-caught birds, leading to the "dead bird project" moniker). Katie and Danielle both decided to work within the thrush specimens that we have acquired and determine how mercury concentrations vary between primary and body feathers. Katie and Danielle are going to continue their projects in the fall, but have summarized their data to include in guest blog posts to follow. I'm so excited to see how this will turn out! Hooray for little bursts of fun science in the middle of a long PhD.
This blog chronicles the sometimes wandering course of my PhD and then my life as an Environmental Studies professor at Purchase College.. Some blog entries will be guest-written by summer interns working with me.