Field Methods

Phantom was sprawled out on a rock, his legs and arms stretched out. Uzat was grooming him; she was focused and working diligently. She also had a really nice estrous swelling. It was a beautiful day and the baboon pair was content. But then, another young female with an estrous swelling named Uganda approached. She went up to Phantom and presented her bum. Uzat was not pleased with this competition — she threatened Uganda, bit down hard on her tail, and did not release for several seconds. After a few more threat displays, Uganda receded. Uzat returned to grooming Phantom.


Photo by Eila Roberts

This was one of my favorite interactions to witness from my time watching baboons. It was not uncommon to see females bicker with one another. But this was special. These two young females both had sexual swellings and they seemed to be competing for the attention of a young male.


It is great fun to witness and tell stories about exciting events like this one. But to really understand and convey what is happening in the lives of animals, we must analyze data that are collected systematically. Fortunately, I was conducting a focal follow on Uzat at the time of this interaction.


Before collecting data in the field, I did not fully understand how hanging out with wild animals resulted in nice figures, statistics, and clear conclusions. Here I will try to make this relationship more clear by describing several methods for data collection.



Collecting behavioral data is complicated. Here is a brief overview of the basics involved.

  1. First, you need an ethogram. Your ethogram is the set of behaviors that you will record.

For our work, we try to keep our ethogram relatively small and focus on what we believe to be the most critical behaviors. By doing this we ensure more accurate data collection. However, others prefer a more extensive ethogram with more detailed behaviors. Each style has its pros and cons.


  1. Decide how you will record your data.

The old school method is pen and paper. Another option is a voice recorder. These can be time consuming, as both methods require manual entry of data into a spreadsheet.

For our project, we use palm pilots. These contain our ethogram and an easy entry procedure. Conveniently, after data are collected, we hook up the palm to a computer and all data are uploaded and nicely formatted into excel!

palm pilot

Recording data on a palm pilot

  1. Decide on the type of data.

Most primate studies involve focal data. During a focal, you follow one individual for a predetermined length of time and using your ethogram, record all relevant behaviors that occur.

By getting a certain number of focals on each individual every week, you are able to tabulate behavior across individuals in a social group.


Other types of data that we collect with our palm pilots include female reproductive state, body condition, nearest neighbors, and ad lib notes. Ad lib is especially useful for rare behaviors such as aggression and mating. When I witnessed such behaviors among the baboons, I recorded them as notes even if I was not focaling the animals involved.


Hormones and Genetics: Poop!




Vance Reeds collecting fecal samples

 We collect fecal samples to obtain information regarding hormone levels and genetics. This is a great way to gather such information on wild animals because it is noninvasive (no darting or blood collection required).

Fecal collection is quite fun with our baboons because their poop is purplish pink due to all of the opuntia fruit they consume!


Growth and body size: Laser camera

New advances allow for accurate measures of body size in wild animals.

To do this, you need a camera with a laser box mounted onto it. Laser boxes have two parallel lights, which will show up on the animal when you take their photograph. We know the distance between the two lasers, so when these are visible on the animal, we can use this information to calculate the length and height of the animal’s body!

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