Animal Behavior at the Bronx Zoo
The purpose of this lab is to further develop your observational skills of animal behavior
and to allow you to informally observe a wide variety of species.
Objectives:
 To gain further experience collecting behavioral data
 To create ethograms
 To develop a testable question about behavior and collect the data to explore this
question further.
Introduction:
Your first goal is to spend about 20 -30 minutes observing animals of your choosing
and to create an ethogram for the species. It is better to choose animals that are not
individually housed and that are not nocturnal (ie. They will be sleeping).
The ethogram is a fundamental tool in the study of behavior. It consists of a
behavioral profile or catalogue of behavioral patterns. Essentially it is an inventory of all
activities of a species throughout its lifetime, organized into categories, and often
incorporating a time budget describing the distribution of these activities.
One of the most important, and difficult, steps in constructing an ethogram is the
naming and defining of behaviors. Each category of behavior should be given a descriptive
name that does not imply anything about its possible cause or motivation. “Grooming”,
“feeding”, “resting”, and “Socializing” are all descriptive references, while “aggressive
behavior” denotes motivation.
Procedure:
1. After selecting an exhibit for observation, simply sit and carefully watch the animals
for 20-30 minutes. During your observations, jot down the various categories of
behavior in which you see the animals engaged.
2. Assign names to these behavioral categories using the guidelines given above.
3. Write out a clear definition of each behavioral category you plan to use. Do not use
tautologies in defining your behaviors, i.e. do not define your behavior category by
using the name of the category. For example, for the category “follow”, an incorrect
definition would be “one animal follows another”. An adequate definition would be
“one animal walks after another”. You should have at least 5 different categories.
4. At the top of your data sheet, record the genus and species of the animals you are
observing, the number of individuals in the enclosure (your count should be divided
into four classes if possible: adult females, adult males, juvenile females, juvenile
males), and the general conditions at the time you begin your recorded observations
(e.g. what is the weather, are the animals inside or outside, are there many or few
observers, have the animals just be fed, etc. Record anything you think might have
an effect on their behavior).
5. Given the ages and sexes of the group that you have chosen to study choose two
age/sex categories to compare in terms of time budgets. Interesting comparisons
include:
 Adult male and adult female
 Juvenile male and juvenile female
 Adult male and juvenile male
 Adult female and juvenile female
6. Think about possible hypotheses for factors that might influence the time budgets of
your subjects. For instance if sex influences time budgets than you might expect
males tamarins to groom more than females. Furthermore, if the function of
grooming is courtship you might expect males to groom in the presence of females
or to only groom other females. Think of a testable hypothesis given our time
constraints, generate a prediction and then collect data on the two categories of
animals that you plan to compare.
7. Select your first individual in the enclosure for study and record its age and sex on
your study sheet.
8. Fill in the behavior category columns.
9. Carry out a focal animal survey using the attached datasheet. Fill in the first time
slot with the current time and then label each subsequent slot in consecutive
minutes. For example, if you will begin your observation of a single individual at
2:07 pm, fill in the first slot with 2:07 pm and fill in the next 29 slots with
consecutive minutes, 2:08, 2:09, 2:10, etc. You should have 30 minutes accounted
for in your record.
10. Now watch your chosen animal for a full 30 minutes, placing a check mark in the
appropriate behavior category column for every minute in which the animal
engages in that behavior. Your study animal may engage in more than one of the
listed categories of behavior during any given minute and these should all be
recorded.
11. You many find it difficult to keep track of your animal’s whereabouts, particularly if
that animal is part of a large group. If the animal goes out of your field of view for
more than a few seconds you should note a “time out” (“TO”) across the category
spaces on your check sheet for that minute and carry on at the end for as many extra
minutes as you need to compensate for the time the animal was out of view.
12. Repeat this process for another individual or individuals. If you are doing 4
individuals you can watch each for 15 minutes.
Report
This report should be typed - not hand-written. The report should begin with a
paragraph describing our selected subjects, group size and composition, and the general
conditions under which your observations were carried out. Next, name and define the
behavioral categories used in your study. These category names and definitions should be
typed as a list, rather than embedded in a paragraph of text. Then identify the ages and sex
classes of the individuals whose behavior you recorded. Describe your hypothesis and
predictions and your reasoning behind them.
Now, summarize your data in graphical form using the graphing software of your
choice. You should represent the percent of total observation time for each animal during
which that animal engaged in each behavioral pattern listed in your “categories”. Thus for
example, if your adult male lemur engaged in feeding behavior during 14 of 30 minutes you
watch him, he fed for 46.7% of the total time he was observed. Graph the data for the
different individuals in different colors and include a legend.
Since your animals may engage in more than one behavior per minute, your bars
may total to more than 100% per individual.
Finally, conclude with a paragraph comparing the time budgets for your subjects. In
what respects are their time budgets similar and how do they differ? Do the differences
agree or disagree with your predictions? For any behavior that clearly differs between your
subject, even if the difference isn’t addressed in your predictions, suggest at least one
hypothesis that might account for the observed difference. If your two subjects were very
similar in a behavior for which you expected them to differ, speculate on why your
observations differed from your predictions.
This write-up should be no more than 2-3 double-spaced, typed pages (excluding your
figure). Your data sheets should be attached as well.