Agua Salud

The Agua Salud Project has three main research areas, as described by our guide:

  1. Secondary forest succession– 50% of land around the canal has been deforested, and the canal authorities want to replace those losses with plantations and/or with replicating the species makeup of native rainforest. Since many plots have been reforested separately over decades, this creates an opportunity for “chronosequencing” and comparing the development of biodiversity across ages without waiting ages. As would be expected, biodiversity can be oversimplified as increasing with age, and vertebrates like monkeys and snakes are far more likely to be seen in the 80-year-old forest than in the 50- and 30-‘s.
  2. Hydrology– The difficulty with crowding woody plants around the canal and river sources is that the roots may soak up too much of the water and prove counterproductive, especially during dry years (like this one) where low water levels put transportation capacity at risk. Agua Salud consists of nine watersheds instrumented with weirs (mini-dams), which are checked weekly for data on water purity and quantity. In doing so, this mainly allows them to test the “sponge hypothesis” and the effects of secondary forest and cattle pastures on water level.

    our guide's own experiment, testing the speed of vascular transport via heat gradients

    our guide’s own experiment, testing the speed of vascular transport via heat gradients

  3. Smart forestation – The last sphere is more direct than observational, and contains several experiments focusing on optimizing water yield/purity, economic gain and biodiversity off what they’ve learned from the first two. For example, one group is testing growth in nitrogen enriched soil vs phosphorous vs both vs neither, with care to place these experiments so that runoff wouldn’t greatly affect readings in the weirs. Another huge experiment is that of narrowing down the best candidates for timber production that help all three areas. Currently teak is rather popular, but it’s a non-native plant and has specific soil demands that aren’t met across all parts of the country. The watersheds in particular consist of a red and nutrient-deficient clay, and teak plantations there have only grown at half the normal rate. As of right now, shade-grown coffee is looking like the best for sponging and the economy, and other native plants they favor include amarillo, cendrospino and cocobolo. So currently they’re taking each of these species in turn and surrounding them with members of another to see how they fare in competition, among other factors.

Due to long term nature of these projects, it’s very common for them to be passed on between scientists and interns over time. Also, we have to be up in >8 hours, hence the brevity. Also, puppies.

Monkeys, Agoutis and Sloths, oh my

view from the dining hall

view from the dining hall

Today we toured a portion Barro Colorado Island, a global icon for biodiversity and rainforest ecosystem research. The island and surrounding lands are owned by the Smithsonian Tropical Research Institute, and we intermittently passed historical study sites along with researchers and their ongoing projects (like lianas’ function as lightning rods). Early on the path parallelled a huge colony of leaf-cutter ants, which initially wasn’t very engaging as we’d seen them almost everywhere. However, a few of the workers were observed carrying from the mound a dead or dying virgin queen. Without going into detail on their eusocial dynamic, this doesn’t seem like a common phenomenon at all, and I wasted a lot of brainpower puzzling over what factors could have led to her dying in the pampered confines of the nest.

general worker activity, sans princess

My favorite moment was when the group stopped to rest and we were passed overhead by a troop of howler monkeys; hearing the howls every day prior built up a lot of anticipation. The troop consisted of 4-5 adults– it’s hard to tell when they’re not all in view simultaneously– and one baby a fraction of the others’ size swinging in their wake. At least one of the adults were male, and the baby was estimated at 9-12 months old by Alex, citing maturation into black fur and behavioral cues (hovering near the mother but swinging independently). All of them were foraging and lazily popping leaves into their mouths, but two of the larger adults descended a few feet further to the ground, lay stomach-down on thick branches, and stared intensely back at us. Given that we weren’t howled at and they took their sweet time leaving, we were seen as more of a curiosity than a threat, but years of researcher activity have definitely familiarized them to the conspicuously colored ground apes. It was also shared among the group that the howler monkeys were of the Golden Mantled variety, and they have prehensile tails exclusive to New World monkeys AND unique prints on those tails and their fingers.


I regret not being able to get pictures [but Logan and Catherine did, badger them!], so here’s a shutterstock image representing the general view we had.

Since there are only so many hours in the day, we’ll wrap up with some miscellaneous fun facts, the first two relayed by our guide Iann:

Fractured habitats not only affect migration, but create opportunities for increased variety and effectiveness of pathogens.

Bufotoxins (from native toads) can act as powerful muscle relaxers, and selective injections have shown temporary effectiveness in treating arrhythmia, stuttering, and strabismus.

According to WebMD, with the amount of while DEET we’ve ingested, we thankfully shouldn’t discover organ damage until after getting home 🙂