Kara Smith

“Observing Intention Movement in the Matschie’s Tree Kangaroo”


  • Zoos have been subject to much scrutiny over the years about whether they provide valuable information regarding behaviors due to lack of simulating habitat (Hosey, 1997). However, currently many zoos have created habitats that simulate an animal’s original habitat, and often have enrichment programs for them. Due to this there is a push to reconnect zoos and behavioral analysts to advance animal behavior in zoos, instead of only using keeper's behavioral notes. Zookeepers have extensive experience observing their organism in captivity, as shown in their behavioral notes. However, more extensive behavioral research/observation is needed to understand an animal's behavior more thoroughly.  Zookeepers do not have the time to do this as they must care for many animals, so this role should be picked up by behavioral analysts (Maple & Segura, 2014). One good thing about zoos is that it makes studying an animal easier and more accessible.
  • The Matschie’s Tree Kangaroo is one of twelve Tree Kangaroo species that live in Papua New Guinea. The Matschie’s Tree Kangaroo has been poorly studied due to the fact that they are hard to observe in the wild due to their fur coloring, arboreal lifestyle, quiet and solitary nature.  Thus little is known about the species. (Porolak et al. 2014 & Garbus & Berlatsky 2016).  
  • The Matschie’s Tree kangaroo would benefit from observing/using zoo inhabitants in order to gather more information about their behavior. Zoos make it easy to study them due to the openness of the enclosure and accessibility.
  • My behavioral observation study focused on the Matschie’s Tree Kangaroo, and how crouching behavior may be an intention movement for jumping. This crouching behavior consists of the tree kangaroo in a crouched position with its head tilted down at the ground, and its posterior end in an elevated position above the head. My hypothesis was that this crouching behavior aids in the jumping movement between trees and allows the Tree Kangaroo to process what its next movement should be.  


Ethogram showing labeled behaviors and descriptions

The data were recorded by observing a Matschie’s Tree Kangaroo at the Columbus Zoo using the continuous focal animal sampling strategy, and using a behavior recording program BORIS. I observed the tree kangaroo for approximately two hours each visit. The behaviors were named and described using an ethogram. The results were analyzed using a kinetic diagram, creating a behavior budget, and statistics were analyzed using R in RStudio.







Figure 1: Behavior Budget for Matschie's Tree Kangaroo

I found that some behaviors, specifically crouching, are more likely to occur prior to jumping than predicted (pvalue= 2.2e-16). There was a strong pattern from crouching to jumping in my kinetic diagram. Crouching went to jumping 44 times and jumping to crouching 27 times. The behavior budget indicated that while sleeping (46.4%), sitting (24.9%), and eating (12.7%) accounted for most of the behavior budget, crouching was responsible for 8.7% of the time spent observing. These results suggest that crouching behavior is an intention movement for jumping. 

The kinetic diagram (left) shows the pattern of behaviors. The lag sequential analysis (right)
shows the number of times the start behavior (left column) turned into the next behavior (top row). The ethogram shows the full behavior names for the abbreviations.



My data suggest that crouching behavior is an intention movement for jumping, which supports my hypothesis that crouching behavior helps to aid the movement between trees. The broader implications of this study are that zoo settings can be a useful tool for learning more about species with little known information, and that are hard to observe in the wild. Future studies could be done in zoos to explore more about aspects of animal behavior.


Literature Cited

Garbus, J., & Berlatsky, N. (2016). Kangaroo, Matschie's Tree. In K. J. Edgar (Ed.), UXL Endangered Species (3rd ed., Vol. 1, pp. 126-129).

Hosey, G. R. (1997). Behavioral research in zoos: academic perspectives. Applied Animal Behavior Science, 51(3-4), 199-207.

Maple, T. L., & Segura, V. D. (2014). Advancing Behavior Analysis in Zoos and Aquariums. The Behavior analyst38(1), 77–91. doi:10.1007/s40614-014-0018-x

Porolak, G., Dabek, L., & Krockenberger, A. K. (2014). Spatial requirements of free-ranging Huon tree kangaroos, Dendrolagus matschiei (Macropodidae), in upper montane forest. PloS one9(3), e91870. doi: 10.1371/journal.pone.0091870