Saturday, February 18, 2012

Ticked Off

So, I teased you guys last week about the mysterious duct tape strapped to my lower legs(see picture in previous blog post). Why did I have it on? What was it’s purpose? Surely it wasn’t purely fashion. Well, the time has come to tell you, and it can be summed up in one word. But I’m not going to make it that easy. The story is as follows.

Our main field site is located high up in the limestone hills behind Montego Bay on the property of a British family who, except for the occasional visit, no longer lives there. They allow us to stay there for a modest fee, and in turn we get a wonderfully convenient field station. The vast property, operated by many local employees, consists of a coffee plantation, an enormous pig farm, and grazing land for hundreds of cattle.. as well as one substantial section of mature wet limestone forest. The main house we’re staying in is called the Copse house, and is on the uppermost tier of the property(more on the house and its inhabitants to come in later posts).To start out with, we will to be working in this one section of mature forest, while later on we will do some work in the coffee, as well as at some other sites around the island.


View from our back porch, looking northeast towards Cockpit Country. The coffee farm is sitting unseen below us, and the pig farm is on the distant hills. Taken by Laura.

So, onto the work itself… Our mission is to catch all of the redstarts and black-throated blue warblers that are spending the winter in this patch of forest. We catch them with mist nets, which are eight feet tall and forty feet long and almost invisible. Once caught, each individual is banded with a unique combination of color bands. This allows for each bird to be identified as an individual later on in the field. Other measurements concerning its weight, health, and size are also taken. We spend the rest of our time mapping out the territories of each individual – the details of which reveal that the oldest males are dominant and thus get the highest quality habitats. Females and young birds live more marginal habitats, whether on the forest edge or in less mature forest. What makes one section of the forest better than the other? Well, hard to say for sure, but it likely comes down to, as with most things in this world, to food. The taller and wetter a section of forest the more diverse and abundant the food source. The taller the forest, the more habitats there are, from canopy, to mid-level, to understory and the ground. A young, second-growth section of forest is unlikely to have as many insect niches, and thus less insects as a whole. To study this dynamic further, we are taking insect samples at all of the sites we will be working.


Above is a photo of a male redstart that we caught. You can see the color bands on him which will help us in resighting him.

But, before we could get started on all that, we had to clear the road from the house to the forest plot. No one else drove that stretch, so it was up to us to tame a years worth of new growth. To make the task more daunting, the entire area was inundated with seed ticks, an exotic visitor from Africa. Drawn to the cattle, hordes of these needle-tip sized beasts sit on top of blades of grass in giant balls of hundreds to thousands of individuals, waiting for you to brush up against them. Once you do, they explode and disperse to infiltrate your being. Ashley, having worked here for three years, knew this and warned us, but there was only so much that words could tell us. She recommended that we each carry a roll of duct tape, and each time a “ball” of ticks got on us, to stop and use duct tape to pull them off as quick as possible. We worked for most of the day using machetes to clear the road before returning to the house in the late afternoon.

Despite my diligence, my clothes had become completely infested with ticks and my body was covered in hundreds upon hundreds of irresistibly itchy red welts. Despite a generous helping of Benadryl, I spent the night in a fitful state of self-mutilation. The next day I had to shave my legs so that I could properly treat them. A week later, the welts were still there, with bloody scabs and new welts rising all around them. There wasn’t a single stretch of skin on my body I could run my hand across without feeling lump after lump after lump. I looked like a poorly shaved poodle with lupus.


The top photo is a piece of duct tape with some seed ticks on it, as well as one giant "silverback" tick. A normal tick ball has about ten times as many as there are on that piece of duct tape. Yes. It sucks. The second photo is of A LOT of ticks, all pulled off at once. Below is my thigh a couple days after the first attack. My whole body looked like this.


Since then, I have learned my enemy and gotten better in my defense, and in turn by body as healed. A typical field day at Copse consists of a dawn departure from the house. My first order of business after breakfast and ablutions is to prepare my defense against the ticks. This entails tucking my quick-dry pants into my socks, wrapping that junction with duct-tape, putting my boots on, and then putting gaiters on after that. Then I tuck my shirt into my underwear, strap on my belt, and I’m ready to go. I always have a roll of duct-tape in my hip pocket, in case I get nailed with a tick ball. If that happens, I rip off a piece of tape and use it to pull off the ticks before they weasel their way into a crevice. We drive up above the house on the track we cleared(bypassing many ticks) to the Copse forest plot, passing through three gates before we enter the forest. The forest itself doesn't have many ticks, thankfully... even though the cows do escape into it every once and awhile.

Once we had caught and color banded some birds, we were able to start mapping out their territories(and still are), and to do this it takes great patience and attention to detail. In addition to the new birds we've caught, there are already several birds banded in previous years that have returned to the plot. To map a bird, I must stalk quietly down the paths that we have cut, listening for the chip notes of the birds to locate them. Once located, I watch it and plot on a grid where I have seen it, at what height in the forest, and what bands it is wearing. After months of doing this, we will have an excellent data set of the habitat partitioning amongst these birds, and what sort of territories each subset of redstart is getting. Perhaps most remarkable of all is the fact that we already know some of the redstarts on territory here have been returning to the exact same tree for the three or four years, all after a migration of over a 1,000 miles.

Of course, one added benefit of setting up a bunch of nets in Jamaica is that you catch a lot of other things as well! On average we have 10-12 nets set up, and have them open for around seven hours a day. Here are some pictures and captions of some of the things we’ve caught. Remember you can click on a photo to make it larger.


Jamaican Woodpecker. Common in all forest types in Jamaica. Taken by Laura.


Rufous-throated Solitaire. Endemic to Hispaniola and Jamaica. The solitaires are members of the thrush family, and have a haunting ethereal song. Taken by Laura.


Jamaican Tody. Todies are only found in the West Indies. Their closest relatives are the motmots and kingfishers. They are quite the sedate little birds, sitting still for long periods of time before flying out after an insect, audibly snapping its wings. Taken by Laura.


Arrow-headed Warbler. A resident warbler species endemic to Jamaica, most often found in wet mid-level forest, gleaning insects from the underside of leaves. Taken by me with Laura's camera.


A male Jamaican Spindalis. One of a group of closely related species endemic to the West Indies, this tanager is common in wet forests of Jamaica, eating fruit. Taken by me with Laura's camera.


A male Kentucky Warbler. This is another migrant warbler species, and one that is listed as a vagrant for Jamaica. However, they are annual at the Copse field site. They breed in bottomland forests of southeastern North America. Taken by me with Laura's camera.

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