Today is our last day of field work at the Ferreira Penna Field Station in the Caxiuanã National Forest Reserve, and as it will be some time before we have all the data analyzed and written up, I thought I’d share some pictures and videos from the last ten days of ants and ant ecologists in the field.
During our stay here, Rogério, Rony, and I worked on four related projects. The grant we have from the Museu Paraense Emílio Goeldi is to compare the respiration rate of ground-nesting ant nests to controls lacking nests. We used an infra-red gas analyzer to measure respiration of soil with and without ant nests, as well as respiration of one arboreal nest of Odontomachus cf. hastatus (click on any of the images to see larger versions):
The data suggest that respiration of Solenopsis > Atta > Odontomachus = Mycocepurus = Pheidole = controls, but we’ve still have the formal analysis to do and the paper to write, and peer-reviewers will evaluate the data, too.
At the same time, we were interested in density of nests, how far the ants wander from their nest to find food, and how readily they can detect it. We worked on these questions by setting out lots of baits—mixtures of crushed sardines with easy-to-follow farinha—and spending a lot of time crawling around the leaf litter following ants around. Besides the obvious amusement value of spending hours on one’s hands and knees deep in a rainforest, we got to see ants and other insects doing all sorts of interesting things.
For example, the tarantula hawk (Pepsis) spent as much time nibbling on Crematogaster ants as it did hauling a spider around:
We saw columns of Pachycondyla emarginata hunting termites and Gnaptogenus hauling a carcass:
While we were doing the respiration measurements, we were able to watch colonies of Mycocepurus building a new chimney:
But perhaps the most rewarding, at least for me (besides learning to use the video editing software on my smartphone), was locating a nest of Pheidole on Wednesday, and then going back on Thursday setting out new baits nearby, and having the colony find it again:
We finished up our fieldwork with a walk up the short solar-power tower in the middle of the ESECAFLOR long-term rainfall exclusion experiment (described in my previous post). Besides being able to see this hectare-scale experiment from above, the view of the forest from atop the tower was a magnificent send-off (click on either image to enlarge).
It’s been a great 10 days, and I hope to come back next year to measure respiration of Azteca nests – in a Tyvek suit!