After an almost year long hiatus - field notes are back! And will hopefully be much more regular this time. Unlike last year, I have consistent access to wifi and the time (at least on my days off) to sit down and write.
As a recap for those who don't know, or have perhaps forgotten:
My research focuses on the impact beavers have on amphibian populations, their genetic diversity, and their connectivity. The working title of my dissertation proposal is "The Beaver and the Frog: The Role of Ecosystem Engineering in Biodiversity Maintenance and Functional Connectivity." Essentially, I want to understand the ways that beavers change landscapes (in their role as ecosystem engineers, or species that change the distribution of resources for other species) and how those landscape changes subsequently impact the amphibians that use both beaver-influenced and non-beaver-influenced wetlands. To do this, I'm surveying 20 catchments (small watersheds) in Grand Teton and Yellowstone National Parks. Within a catchment, I visit every wetland I can find, collect and environmental DNa (eDNA) sample, conduct visual encounter surveys for tadpoles and adult amphibians, and collect tissue samples from the individuals I do encounter for later genetic analyses.
The goal of the eDNA samples is to improve our rate of detection. Amphibians can often be cryptic. Populations within a given wetland may be so small that we can't find any, the weather may make them less active or harder to see (like when it's as overcast and cold as it has been this week), and sometimes our sites are so big we aren't able to survey all of the available habitat. Environmental DNA, which is the DNA left behind in the water by sloughed off skin, failed eggs, gametes, and excretions, can help us detect species we didn't see during the visual surveys. So at each site, we collect a liter of water and run it through a small paper filter, whose pores are small enough to let water through but catch the DNA molecules. In the lab, I'll process these samples and test for the presence of each amphibian species.
We started our field season last Monday, driving from Laramie, in the southeast corner of Wyoming, to Yellowstone National Park, in the northwest. "We" this year is me and my field tech, Gage. Gage is a recent graduate of the University of Missouri, and she spent last summer collecting eDNA samples and surveying for the foothill yellow-legged frog (a candidate for listing under the Endangered Species Act) in Oregon. That previous experience has really paid off, because she had to hit the ground running with me.
Monday night, we met up with the National Parks Service amphibian monitoring crews, who I trained with last year (check out this blog for more details). On Tuesday, we were out in the field with them, visiting some sites on the Northern Range that they always do early on in the season. We collected eDNA samples and gave the crews a quick tutorial (as they'l be collecting some samples for me this year), and Gage got to see her first boreal toad and boreal toad tadpoles. On Wednesday, we started off the day hiding from the rain in a visitor's center, then followed the crews to a brand new site they hadn't survey before, where we saw salamander eggs, before deciding to head out on our own in search of the species and life stages we were more likely to encounter this year. Armed with a GPS point recommended by the crews, we drove out to a site where, the week before, they had seen 3 of the 4 species commonly found in the parks.
As we got to the GPS point, we started to see quick little movements in the slightly flooded grass. Looking closer, we spotted tiny frogs, less than an inch long. These were adult boreal chorus frogs. At their biggest (which these were definitely not), they're about as long as my thumb. Within a few minutes though, we came across some deeper puddles and found Columbia spotted frogs, which are much larger, hanging out in the mud. Columbia spotted frogs are kind of your "classic" frog, the one you picture when you picture a frog. Long, webbed feet, highly aquatic, prone to leaping into the water with a resounding "plop" when startled.
After spending a while comparing the two adults, we moved to a different pond, one I visited with the crews last year. In this pond, we quickly found boreal chorus frog tadpoles. Then we came across a salamander larvae. And finally, visiting a third spot, we found the very chunky tadpoles that could only be Columbia spotted frogs. In the span of an hour, Gage had seen almost every species and lifestage she need to know on sight, other than the toads we saw the day before.
And it was a good thing too, because we hit the ground running the next day, driving south to Grand Teton National Park, checking into the University of Wyoming - National Parks Service Research Station, con
tinuing south to one of our catchments, and hiking uphill 2km to the first site.
Only to realize...we had forgotten a very vital piece of equipment.
Our nets.
Without which, you cannot conduct a survey.
Dejected, we turned around, hiked back down the hill, and decided getting groceries in Jackson was the best use of our day, and we would come back the next.
Needless to say, we triple check that we have our nets now.
Talk about a #FieldworkFail.
The next day, we revisited that catchment, which only has two sites, giving Gage a pretty good introduction to doing everything on our own, without the crews. We surveyed the first site without a problem, hiked over to the second, larger site, and had just gotten started when the skies decided to open up on us and starting raining heavily. After trying to wait it out for a while, we decided to cut the survey short (we already had our eDNA sample) and wrap up that catchment.
The next day was our first intense day of fieldwork. The catchment we visited is one that Luis likes to describe as "similar to the trenches of the first World War." The geology of the area is unique, with many very round depressions, many of which fill with water and become shockingly productive wetlands. But, the surrounding area is forested, and full of dead, fallen trees. Getting over and around the trees is likely a very unpleasant maze, where you get stabbed by an unnoticed branch and try not to slip when the logs get slippery from the rain. You try to maintain your bearing towards the next site, and end up having to walk in a wide arc just to get around the trees. It can be exhausting.
We surveyed 8 sites the first day, and none of them were dry. The second day in that same catchment, we visited the other 9 sites we had identified last year, and only one was dry. Last year there were 4 without water. Quite the difference.
On each of those days, according to my Fitbit, we walked over 10 miles, through those downed trees. We were, needless to say, exhausted by the time we got back to the research station last night. Not to mention, it rained constantly all day yesterday. We were tired, soaked, chilled to the bone, and infinitely grateful to have access to hot showers, a real kitchen, and beds with mattresses this year.
Bravo Kate, bisous !