What is a focal follow? (aka. what I do all day)

Field Assistants Sheila and Sylvia in T-West North group

My study is observational, not experimental. Observations and experiments go hand-in-hand, but are different: experimenters manipulate conditions and observers do not (e.g. day length in colony room vs. day length according to natural season). In both types of studies, the researcher measures one or more conditions (e.g. day length) and response variables of interest (e.g. song frequency of birds). You may sometimes hear of "natural experiments" - these are times when mama nature herself (aka God +/- chance) is the manipulator, creating different conditions across which researchers measure and compare a response. For example, to see the effect of military service on income, a researcher could compare the income of veterans vs. non-veterans, given a random draft. Most observational studies take advantage of these natural experimental conditions, and so do I. Take away: I observe the monkeys' behavior with little to no involvement in it.

In 1974, a smart woman named Jeanne Altmann did everyone in the emerging field of behavioral ecology a big favor - she wrote "Observational Study of Behavior: Sampling Methods." In doing so she succinctly described the various ways that people can (and perhaps should) sample spontaneously occurring behavior. One of these ways, now ubiquitously common, is called the "focal follow." And in the focal follow you can employ a variety of recording techniques…

Frisbee, Sheila, and our digital data sheets

Focal follows are what we do for most of the day here. We follow a "focal" animal (i.e. one of our subjects) for 20 minutes, during which we record all of its social interactions. If I'm following Bike, for example, then I might write line by line in our code "bike receives approach from frisbee"…"bike receives groom present from frisbee, bike accepts and grooms frisbee". Then every minute on the minute, alerted by our repeating timers, we record what Bike is doing (e.g. feeding, resting, moving, grooming) and who is nearby. If Bike moves out of sight for more than 10 minutes in a row… we wail, shake an angry fist to the sky, and abort the follow. If we follow Bike for the full 20 minutes… then we cheer, bust a Saturday-night-fever, and move on to find another focal.

We try to do the same number of follows for each subject each month and conduct those follows evenly throughout the day…

Game-face time: the forest
observers and monkeys traverse

About 80% of the time the monkeys are high up in the trees (30-50m), so you need your game face (focus hard and write quickly) to avoid shaking that angry fist to the sky. When monkeys decide to move, they move! This poses a problem for us lumbering terrestrial bipeds. The treetops and underbrush are paved rode for the monkeys' lithe little bodies and nimble hands and feet, but they're less accommodating for us.

Nevertheless, there is that lovely 15% of the time when the monkeys come low, and the 5% when the follow is an absolute and glorious cakewalk. See above a photo of Sheila's cakewalk with Frisbee and a view of our tablet interface.

I'll save the fun details of how we collect hormone samples (pee and poop!) for another time. 

I hope you've enjoyed a glimpse into the world of focal follows! For more details, please just ask ;).

Lots of love,

Nicole