While Diana and Malena headed out on another night walk, Dan, Choru and I set up the mercury vapor light trap again in front of my cabin. As we tied the white sheets, and turned on the light, the wind was picking up speed. We had been warned that a “friaje”, a cold polar wind coming up from Patagonia, was heading our way. Despite the wind, the number of insects coming to our sheet was low, the diversity was still good, with some unusual specimens we had not sampled before.
A very nice colony of oropendola birds was nesting outside our lab. We became accustomed to their comings and goings and admired their long, basket-like nests and gargling calls. They always seemed to come and go together and did so with much fanfare. One afternoon however, while the birds were away, three capuchin monkeys raided their nests, and we were lucky to see it. The capuchins systematically went to each one, inserted their heads and torsos into the long nests, pulled out the oropendola eggs, and ate them right there in front of us. It was quite shocking.
Our days have developed into a pattern of servicing the traps in the mornings: picking up all the arthropods collected by the traps, returning to the lab and processing the specimens (cleaning, sorting, labeling), then each person going off in a different direction to use specialist techniques to collect their favorite group. I spend the afternoons surveying palms, heliconias and bamboos for their particular fauna of chrysomelid beetles.
Today is a big day: reviewing the available established plant plots in the area, relocating their markers (boundaries of edges and internal sub-quadrats), selecting a plot we will follow in the next few years, and setting up several kinds of traps to capture insects. One of the reasons arthropods are so diverse is because they divide any habitat into 1000s of microhabitats, with many insects specializing on particular aspects – flower feeders, seed drillers, stem and leaf miners, soil arthropods, root feeders, parasites, parasitoids, predators….an insect specialist must h
post by Malena Vilchez, of the Peru research team
At night, armed with head lamps and UV torches (and a lot of bug spray), you can actually see tons of spiders and other nocturnal arthropods doing what they live for, i.e., eating, preying, mating, etc. without much search effort. During the daytime, you have to look harder for the various microhabitats; of course, it is easy see the orb weaver spiders as well as some other weavers and a few cursorial spiders but this is only a small portion of the total spider fauna.
We awoke to rain....heavy rain..…that kind of Amazon rain where you can’t keep your eyelids open and that promises to last all day. And we are in the middle of the dry season! Well, this is time to recover from hectic preparations in Kansas, the long journey here, and to orient to our new home. This field station’s set meal schedule (6 am, 12 noon, 6.30 pm) allows all the current station residents to meet. It is a great opportunity to learn about other exciting research going on here.
For my third visit to Peru, I am developing a system of long-term sampling plots distributed along an elevational transect from the lowland Amazon to the Andes, up to ~3500 m. I can select plots already established by botanists who have been working here for about 30 years. It is an uncommon ideal to have most of the plants known in a tropical habitat before I start looking for the herbivores of those plants.
We are finally in Peru for my third expedition. I visited alone previously to explore the diversity of chrysomelid leaf beetles and their host plants. During the first trip in 2007, I discovered how wonderful a field station can be, as opposed to expeditions involving daily travel from one campsite to another, hauling food, water, supplies, and, for me, tubs of live baby insects that I am trying to rear to adults before I run out of their food plant from the last site. (Baby insect systematics is so primitive that without the adult, I have no hope of identifying the species.)