A Mixed-Species Flock

September 16, 2013

For our second full day at Maromizaha, my group joined up with a well-known naturalist for an introduction to how researchers conduct transect surveys. Though simple in design, transect surveys are extremely useful for determining species density within a rainforest. Because lemurs and birds were a little too quick for us beginners, we conducted our transects with orchids as our focal organisms.

So we hiked up to Belle Vue— a ridge that arguably provides the best view in the reserve. It was a tough hike, but when we did finally reach the top, we were greeted with a wonderful view.

(pic)

We heard some Indris up here and a few people were able to see some distant black and white shapes, but the coolest thing (at least in my opinion) was the mixed-species flock we ran into.

In the tropics, many species of small, forest-dwelling birds will travel in groups comprised of several different species. Why they do this instead of sticking exclusively with their own kind is hotly debated, but the most popular theory is that strength in numbers increases the chances of finding food and decreases the risk of predation.

On the previous day’s hike through Maromizaha, I had seen a few Madagascar Brush Warblers, Madagascar Bulbuls, many Souimanga Sunbirds, and a single Red-Fronted Coua that appeared while everyone else was admiring the Sifakas— but I hadn’t seen any vangas, asities, or other forest specialties until today.

It began with the Souimanga Sunbirds. I had seen or heard at least 20 of them on the hike today, so I didn't think it was a big deal when a pair popped into view along the edge of the forest. And then a Crested Drongo appeared. Two Crested Drongos... Five Madagascar White-Eyes... Three Blue Vangas (!!!)… Two White-Headed Vangas… Two Red-Tailed Vangas… Common Newtonias… more sunbirds… and then, a slightly larger sunbird with bright green goggles appeared: A Common Sunbird-Asity!!!