Over the last semester I've been developing my own research ideas. Basically I'll be examining variation in direct and indirect tritrophic interactions (that is interactions between plants, herbivores that eat the plants, and the herbivore's natural enemies) from a couple of different perspectives. The first involves searching for the presence of any type of latitudinal gradient in the strength of these interactions, while the second will look at any differences in the interaction strength between the three known types of Phragmites in North America, two of which are considered invasive from Europe, and one of which is native. Essentially, this could provide valuable information about why the invasive genotypes have spread so rapidly in the United States. Along with Jim and Ganesh I'll be collecting data on plant characteristics and quality, aphid density and other herbivore damage, predator and parasitoid density, as well as sampling all sorts of insects from the Phragmites habitat using a range of methods.
Over the course of the trip I'm going to post some updates and photos every couple of days to document the coolest parts of my trip, so here's the first one.
DAY ONE
Leaving Baton Rouge at 6 am we arrived in Charleston, South Carolina, 14 hours later, probably the longest I've ever spent in a car. Then the first thing we see is someone being arrested at gunpoint surrounded by eight police cars about 200 metres from our hotel. Sadly that was the most exciting part of the day, as it was mostly spent driving the mostly boring highways of Louisiana, Mississippi, Alabama, Georgia, and South Carolina. The only other highlight of the day was having Mexican for dinner and discovering a new favourite food, fajitas!
DAY TWO
The second day of the trip was when we finally got stuck in to the field work with our first site in Georgetown. It was a relatively easy site and we finished our census in about 90 minutes as most of the Phragmites patch had been burned the previous fall and the regrowth was short and sparse this early into summer. Driving the six or so hours further north to Elizabeth City was a bit more interesting than the drive the previous day, mainly because the scenery was not so monotonous and we also had some excitement driving through a thunderstorm with rain so heavy we couldn't see more than 30 metres ahead.
 |
| Jetty at the Georgetown site |
Today we saw a lot of action. The day started at 4:30 am so we could arrive at the Currituck ferry early enough to make sure we got on the 6 am trip across the sound to Mackay Island Wildlife Refuge, the location of our next three sites. We met with Tim, one of the refuge workers, whose job all day was to take us by boat to all our sites out in the marsh. Two of the three sites were to be my first glimpses of patches of native Phragmites which I was also excited about.
The thing I was most excited (and apprehensive) about was the possibility of seeing a cottonmouth snake, a highly venomous and aggressive snake which is really abundant in Mackay Island. As it turned out, about 20 minutes into our work, Jim had a close encounter with one which was probably too close to comfort. Cottonmouths, or water moccasins as they're also called, are famous for not being scared of humans. In fact, when approached they stand their ground, coil, and gape at the threat, while some are known to approach the intruder. As they're well camouflaged in the marsh it's really easy to step on them without noticing as Jim almost found out. He was mapping the perimeter of our patch when we heard him shout out; turns out he was less than half a metre away from a large cottonmouth when he finally noticed it's open mouth. This put us on high alert for the rest of the day, and I even saw a cottonmouth of my own. It was just a small one, less than a metre in length, but it still got my heart racing when I saw it only 1 metre off the side of my trail. I stood and watched it for a minute before it slowly started swimming away.
As for the work itself, it was a tiring day, especially when you're watching where you put your feet every step! The marsh was quite waterlogged, and had lots of holes up to hip deep. The result - wet boots, socks, and pants. At 3 pm, with about one hour of work to go, a big thunderstorm broke. Tim told us that it was very dangerous to be out in the marsh in a metal boat during a thunderstorm and that he had dragged out four dead bodies from lightning strikes over his years at the refuge. We didn't want to make that number any higher so we sped back to the truck to wait it out. After a couple of hours wait and hearing that there was golf ball sized hail about 3 km away we decided to get out of there and come back in the morning.
 |
| Phragmites as far as the eye can see, the native genotype in this case |
 |
| Tim and Jim in the boat |
DAY FOUR
We returned to Mackay Island for a 7:30 am start, knocking out the remaining work in about two hours. There were no more close encounters with cottonmouth snakes but we did see a couple swimming in the creek from a distance. After finishing up at Mackay Island we headed around three hours north to our site at the Rappahannock River in Virginia. This site was fairly tame with only a few sinkholes in the marsh to fall into. It also had very low aphid numbers. Maryland and Delaware are on the agenda tomorrow.
 |
| Ganesh heading through a wheat field on the way back from Rappahannock |
No comments:
Post a Comment