Copy of my presentation about my undergraduate research concerning squirrel behavior in urban parks in Montreal, Canada, to Chicago State University in the Fall of 2010.

1. Home-Range Security
A Fresh Look at
Foraging
and Anti-Predation
Behavior in
Eastern Grey Squirrels
Noah Sager
18 November 2010
Chicago State University
Department of Geography

2. The Field
 Behavioral Ecology
 The study of an animal’s behavior (decisions) dependent
upon its environment, and the conferred adaptive benefits or
costs
 Behavioral Geography
 The study of a human’s behavior (decisions) dependent
upon its environment, and the conferred adaptive benefits or
costs

3. Why Psychoanalyze Animals?
 “True” Science
 Applications
 Correlations
http://www.cartoonstock.com/lowres/sma0070l.jpg

4. The Eastern Grey Squirrel
(Sciurus carolinensis)
Small (~400g)
Scatter-hoarding
Diurnal
Spatial Memory
Nests
Intermittent Locomotion
http://www.sciencedaily.com/images/2009/07/090728102303-large.jpg

5. Definitions
 Anti-Predator Vigilance
 ‘Early-warning’ behavior that enables animals to avoid predation
(e.g. predator detection)
 Intermittent Locomotion
 Cyclical movement of motion, pause (vigilance), motion
 Foraging
 The gathering and subsequent consumption or scatter-hoarding of
food items
 Scatter-hoarding
 The burying or hoarding of food items in individual locations

6. Pause Postures
Left to Right
Extended Upright
Upright
Semi-Upright
Quadrupedal Up*
Quadrupedal Down*
Tripedal*

7. Previous Studies
 Wistrand (1974)
 Newman et al. (1988) http://farm4.static.flickr.com/3402/3261412644_9a6c4be2c1.jpg
 Jones (1998)
 McAdam & Kramer (1998)
 Tchabovsky et al. (2001)
 Trouilloud et al. (2004)
http://www.hiltonpond.org/images/ChipmunkEastern06.jpg

8. Anti-Predator Vigilance:
Feed or Flee?
 Study Area
 Urban parks around Montreal, Quebec (Canada)
 Summer of 2004
 Description
 The non-invasive video recording of squirrel behavior at artificial
foraging patches with varying distances from cover
 Materials
 digital video camera, food dish, measuring tape, sand, stakes
 peanuts, peanut butter, sunflower seeds

9. Anti-Predator Vigilance:
Food or Foe?
 Methods
 36 squirrels (1 per site)
 100m distance between sites http://insidevalleyforgepark.pbworks.com/f/IMG_0186.JPG
 3 distances from cover (0.3m, 5m and 15m)
 Newman et al. (1988)
 Food patch: 1 liter ‘treated’ sand patch with inverted food dish
25 whole sunflower seeds (15 buried), 1/4 tsp. creamy peanut butter,
5 whole peanuts
 Confounding conspecifics
 End of trial requirements

10. Anti-Predator Vigilance:
Forage or Die Trying
 Data Extraction
 Noldus Observer
 Digital recordings analyzed frame-by-frame
 Behavior Durations and Frequency
 Locomotion
 Pauses
 Transition Times
 Motion to Pause (locomotion to vigilance)
 Pause to Pause (pause posture to posture)
 Pause to Motion (vigilance to locomotion)

11. Anti-Predator Vigilance:
It’s a Dog Eat Squirrel World
 Data Analysis
 One and two-way ANOVAs (analysis of variance)
 Bonferroni corrections (post-hoc)
 Question 1: Are more upright (more vigilant) pause postures
really more costly?
 Question 2: Are transition durations dependent upon pause
posture?
 Question 3: Is there an effect of distance from cover on pause
duration or transition times?
 Question 4: Is there a vigilance component to foraging?

12. Results
Pause durations varied significantly depending upon posture, with upright pauses lasting longer than semi-
upright pauses (F2,52=8.657, P<0.01), and semi-upright pauses lasting longer than quadrupedal pauses
(F2,46=3.115, P<0.01), and this was still significant following a Bonferroni post-hoc test.

13. Results
Posture type had a significant effect on transition times, requiring more time for a squirrel to move from
locomotion to a semi-upright posture than to a quadrupedal posture (F2,52=49.396, P<0.01) and more time to
move to locomotion from a semi-upright posture than from a quadrupedal posture (F2,66=68.910, P<0.01),
and this was still significant following a Bonferroni post-hoc test.

14. Results
There was a slight effect of distance on transition times to move from locomotion to quadrupedal alert
(F2,44=0.067, P=0.057), but no effect from locomotion to semi-upright alert posture (F2,42=0.270, P=0.758).
Accordingly, there was no effect of distance on transition times moving from quadrupedal alert to
locomotion (F2,58=0.065, P=0.352), to semi-upright alert (F2,32=0.351, P=0.707), or from semi-upright alert to
locomotion (F2,49=0.600, P=0.553). There was no effect of distance from cover on pause duration for all
postures (F3,31=0.902, P=0.409).

15. Results
Left: Frequency Distribution of Quadrupedal Pauses During Locomotion. Duration category is measured by
number of frames (1 Frame = 1/30 seconds). n = 624, mean = 3.92, median = 8.
Right : Frequency Distribution of Quadrupedal Pauses In Patch. Duration category is measured by
number of frames (1 Frame = 1/30 seconds). n = 164, mean = 14.37, median = 7.
(see: Makowska & Kramer 2007)

16. Discussion
 Question 1: Are more upright (more vigilant) pause postures
really more costly?
 Supported (first empirical evidence)
 Question 2: Are transition durations dependent upon pause
posture?
 Supported (first empirical evidence)
 Question 3: Is there an effect of distance from cover on pause
duration or transition times?
 Failed to support (contrary to previous studies)
 Question 4: Is there a vigilance component to foraging?
 Failed to support (requires future studies)

17. Conclusion(s)
 Vigilance is costly
 Positive correlation between pause duration and posture,
and between transition time and posture
 Constrained decisions, time-budget
 Squirrels maintain a constant time-budget concerning
foraging and anti-predation activities
 Vigilance trade-offs
 Distance from Cover versus Detection Range*

18. Acknowledgements
 McGill University - Behavioural Ecology Lab
 2004 - 2005
 Dr. Donald L. Kramer
 Research Supervisor
 Talya Hackett
 Field Assistant
 The Squirrels
 Numbers 1 - ?

19. Questions or Comments?
http://pixdaus.com/pics/1226742504ehmpYPF.jpg