Research

The Gorilla SSP® Research Advisors are Dr. Nancy Hawkes and Elena Less. Along with them, the SSP is supported by several other research scientists that help guide important scientific-based management principles.

An ethogram is a catalog of a species' behavioral repertoire. The Gorilla Behavior Advisory Group of the Gorilla SSP has compiled a compilation of over 45 gorilla ethograms.

To cite this document (APA format):

Ogden, J., Schildkraut, D., Baker, A., Beck, B.B., Bennett, C., duBois, T. et al. (1991). Compilation of gorilla ethograms. Atlanta, Georgia: Gorilla Species Survival Plan, Gorilla Behavior Advisory Group.

AZA Gorilla Research Overview
Gorillas in captivity provide opportunities both to learn about the species and to use science to improve the well-being of its captive members.
See a list of publications generated from research on gorillas in AZA zoos, 2002-2006.
Studies listed here are taken from AZA's Annual Report on Conservation and Science.

Submitting a Proposal:
Any researcher may submit a proposal to the Gorilla SSP for endorsement/approval for the following reasons:
1. To encourage AZA institutions housing gorillas to participate in their research project
2. To obtain a letter of endorsement/approval of their research project to aid in receiving funding.
3. To gain access to the gorilla studbook.

Definitions of Voting Classifications for Proposals Submitted to the Gorilla SSP Management Group:

• ENDORSE: High priority, good science; we highly encourage zoos to do whatever they can to accommodate project; furthers goals of the Gorilla SSP
• APPROVE: Moderate priority, good science; institutions should participate if they can
• PASS: Low priority, questionable science; not relevant to Gorilla SSP goals
• NEED MORE INFORMATION
  

Endorsed Projects

Removal of Primate Chow from Gorilla Diets: The Impact on Behavior,
Adiposity and Health
Elena Hoellein Less (Cleveland Metroparks Zoo), Richard Bergl, Ph.D. (North Carolina Zoo), Shana Lavin, Ph.D. (Lincoln Park Zoo), Pam Dennis, Ph.D., D.V.M. (Cleveland Metroparks Zoo), Sylvia Atsalis, Ph.D. (CRES, The Zoological Society of San Diego), Kristen Lukas, Ph.D. (Cleveland Metroparks Zoo), and Christopher Kuhar, Ph.D. (Cleveland Metroparks Zoo)
The proposed study examines the influence of typical captive diets on gorilla behavior, obesity and overall health. In particular, we propose that for captive western lowland gorillas, replacing chow and fruit with larger quantities of plant material will reduce undesirable behaviors, increase activity and reduce adiposity. To test this hypothesis, we will: measure the amount of time engaged in physical activity (i.e. foraging, climbing, running, etc...) and the rate of feeding-related undesirable behaviors according to the two different diet types; determine concentrations of serum hormones related to adiposity and biological markers of inflammation; examine stool volatile fatty acids; and apply body measurement indices of physical condition in a sample of captive western lowland gorillas.

Adiposity in Captive Gorillas: Variance in BMI, Diet, and Activity Levels
Elena Hoellein Less (Cleveland Metroparks Zoo), Pam Dennis, Ph.D., D.V.M. (Cleveland Metroparks Zoo), Kristen Lukas, Ph.D. (Cleveland Metroparks Zoo), Christopher Kuhar, Ph.D. (Cleveland Metroparks Zoo), and Mary Ann Raghanti, Ph.D.
(Kent State University)
The proposed study examines the influence of diet and activity level on gorilla adiposity. In particular, we propose that for captive western lowland gorillas, those gorillas that are fed a diet more similar to their wild counterparts and/or spend a large percentage of time active will have lower adiposity as reflected by body mass index and hormone levels. To test these hypotheses, we propose to survey the diet composition and feeding protocol along with activity levels in all gorillas housed in Association of Zoo and Aquarium institutions. In conjunction with assessing diet and activity we will measure (1) serum hormone concentrations related to adiposity, (2) biological markers of inflammation and (3) body measurement indices.

Training videos for data collectors (right-click to save the movie files to your computer):

Gorilla Video Ethogram (18.3 MB Windows Media file)
Data Collection Training Video (38.2 MB Windows Media file)
Reliability Test One (37.7 MB Windows Media file)
Reliability Test Two (37.5 MB Windows Media file)

 

Evaluation of Risk Factors Associated with Cardiac Disease in Gorillas in AZA Institutions
Ilana Kutinsky, M.D.(Beaumont Hospitals, MI), Suzan Murray, D.V.M. (Smithsonian National Zoological Park), Tom Meehan, D.V.M. (Chicago Zoological Society/ Brookfield Zoo), Hayley Murphy, D.V.M. (Zoo New England), and Pam Dennis, D.V.M., Ph.D. (Cleveland Metroparks Zoo and The Ohio State University)
Cardiac disease is a major cause of death for gorillas in AZA institutions. This project seeks to form a comprehensive database incorporating information from individual gorillas' medical, nutrition and husbandry records and to also address the diagnostic challenges associated with identifying heart disease in zoo gorillas.

Pan-African Sanctuary Alliance (PASA) Ape Modeling Project
Lisa Faust, Ph.D. (Lincoln Park Zoo) and Ben Beck, Ph.D. (Great Ape Trust)
This project's focus is on modeling the demography of representative great ape sanctuary populations using the captive population studbook to project the amount of space needed to house existing sanctuary specimens and accommodate new specimens being confiscated. The model should provide a valuable example of the time and resources required to maintain confiscated ape populations throughout their natural lifespan, giving sanctuaries a better understanding of the nature and extent of their commitment.

Gorilla Personality and Subjective Well-Being Assessment
Alexander Weiss, Ph.D. (University of Edinburgh)
This study's focus is on using gorilla personality as a measure of subjective well-being. The results of this study will be used to compare gorilla personality to that of other great ape species, including humans as well as analyze possible genetic, environmental or maternal influences on development of personality in gorillas.

Detection of SIVgor Infection in Captive Gorillas
Brandon Keele, Ph.D. (University of Alabama) and Beatrice Hahn, M.D. (University of Alabama)
There was recently reported in Nature evidence of a naturally occurring simian immunodeficiency virus infection in wild gorillas (G. g. gorilla) which was designated as SIVgor. The objective of this study is to determine if any captive gorillas are likewise infected. This study requests either plasma or fecal samples for each captive gorilla.

Assisted Reproduction Using Sex-Sorted Sperm: A Management Strategy for Captive Gorillas
Naida Loskutoff, Ph.D. (Henry Doorly Zoo)
In light of the precarious state of gorillas in their natural habitats, the American Zoo and Aquarium Association (AZA) Gorilla Species Survival Plan (SSP) proposes the application of assisted reproductive technology as a means for allowing the genetic contributions of these animals to increase the likelihood of long-term genetic health and survival of the species. The aim of this research is to use the most recent advances in human assisted reproductive technologies as a model to develop methodology for producing female offspring from genetically underrepresented individuals in the Gorilla SSP. This study requests sperm samples from male gorillas and oocytes for female gorillas.

Alcohol Metabolism, Primate Evolution and Paleogenetics
Matthew Carrigan, Ph.D. and Steven Benner, Ph.D. (Foundation for Applied
Molecular Evolution)
Alchohol dehydrogenase (ADH) and aldehyde dehydrogenase (AlDH) are two enzymes important in the detoxification of alcohols, including ethanol. We are a non-profit research foundation that has recently been funded by National Institute on Alcohol Abuse and Alcoholism (NIAAA) and the National Institute of Environmental Health Sciences (NIEHS), both part of the National Institutes of Health (NIH), to study the evolution of these proteins within the primate lineage. Ethanol was not always present in the environment, and it is therefore expected that evolutionary adaptation has occurred within these lineages since its introduction. We currently have the sequences of the ADH and AlDH genes for humans, pan troglodytes, and macaca mulatta (along with partial sequences for pongo pygmaeus, gorilla gorilla, and papio hamadryas) through the NCBI genome database. We wish to expand upon the public database by sequencing the genes from as many other primates as possible, and to these ends, we seek the help of the larger zoo community. The exact species of the primates we use in our study is of less importance than obtaining genetic information from a wide diversity of primates, including representatives from each of the major evolutionary branches.

Examining the Role of Nuclear Translocations of Mitochondrial DNA as Genetic Markers in Great Apes
Nicola Anthony, Ph.D. (University of New Orleans) and Michael Jensen-Seaman, Ph.D. (Duquesne University)
This study aims to examine genomic sequence databases of African apes to search for translocations in mitochondrial DNA, to understand the mechanisms of these gene translocations, and to evaluate their usefulness as genetic markers. This study may provide information about the geographical origins of captive gorillas informing breeding recommendations.
Update: The first specific aim of our study focuses on the retrieval of nuclear copies of mitochondrial DNA (Numts) encompassing the control region (CR) of humans, chimpanzees and gorillas. To do this, we are using BLAST surveys of pubic human and chimpanzee genome databases and CR screens of an existing gorilla BAC library and nuclear DNA enriched genomic libraries prepared from sperm heads isolated from multiple individuals. With respect to the latter, we have obtained sperm samples from the Henry Doorly Zoo in Omaha and the Audubon Center for Research of Endangered Species (ACRES) in New Orleans. However, DNA concentrations have proved insufficient for us to build a library with existing resources so we have applied to the Coriell Institute for Medical Research for access to gorilla cell lines which we intend to use as a source of genomic DNA for library construction. The second specific aim of our work focuses on characterization of nuclear sequences flanking Numt loci obtained from the first specific aim to assess whether Numts integrate randomly within the genome or are preferentially associated with either transposable elements (TEs) or other sequence motifs. To date, we have found that Numt insertion events do not appear to be associated with TE but instead appear to have been facilitated by micro-homologies between the mitochondrial fragment and nuclear point of insertion. Our third and final aim focuses on building a panel of gorilla samples from the US Zoo network in order to (i) assess the utility of gorilla-specific Numts as population genetic markers for reconstructing gorilla evolutionary history (ii) identify the likely geographic origin of gorillas in captivity based on our extensive work on mitochondrial variation in free-ranging populations. We have assembled a database of all known matrilines within the U.S. Zoo network and begun to request samples from institutions where these animals are held. To date, Audubon Zoo in New Orleans has donated blood samples from their 3 gorillas. However, we would greatly appreciate additional samples of gorilla blood, faeces or shed hair from other zoos and foresee continued work in this last phase of the project for the next year or so.

Gorilla Population Histories
Linda Vigilant, Ph.D. (Max Planck Institute for Evolutionary Anthropology) and Richard Bergl, Ph.D. (North Carolina Zoological Park)
The specific aim of the project is to generate large amounts (> 50kb) of nuclear sequence data from western and eastern gorillas in order to improve the estimate of how long ago the two taxa diverged from one another, and estimate the amount, direction and duration of gene flow among these different populations. This project will also illuminate the extent to which the one-male mating system of gorillas has altered relative levels of genetic variation on the Y-chromosome, X-chromosome and autosomes relative to the levels found in chimpanzees and humans.

COMPLETED GORILLA SSP RESEARCH PROJECTS

Cataloging Blood Types for SSP Populations of Great Apes
Kathryn Gamble, D.V.M., M.S. (Lincoln Park Zoo) and Jill Moyse (Lincoln Park Zoo)
In humans and domestic mammals, blood typing plays an important role
in providing excellent medical care in critical care situations. It has been repeatedly demonstrated in the literature that humans and great apes have conserved identities within the standard blood typing categories of A-B-O and D(Rh factor). Development of simple table-top laboratories techniques to identify these most basic of blood groups in human patients may be applied to similar benefit in the great ape species.
Update: This study is complete and authors are currently preparing the study for publication. When available, we will post a summary of results.

Assessing the Prevalence and Characteristics of Hair Plucking Behavior in Captive Western Lowland Gorillas (Gorilla gorilla gorilla)
Elena Less (Cleveland Metroparks Zoo) and Kristen Lukas, Ph.D. (Cleveland Metroparks Zoo)
This study's focus is on describing hair plucking behavior in captive gorillas, as well as evaluating risk factors that may predispose gorillas to exhibit this behavior. The results will be used to inform captive management decisions on ameliorating this behavior in the captive population.
Update: This survey is complete and data is currently being analyzed by the PI. The authors wish to thank the 38 zoos who participated.

Captive Great Apes and Their Interactions with Local Wildlife
Steve Ross (Lincoln Park Zoo) and Elizabeth Lonsdorf (Lincoln Park Zoo)
Although there are published reports of wild chimpanzees, bonobos, and orangutans hunting and consuming vertebrate prey, data pertaining to captive apes remain sparse. In this survey-based study, we evaluate the prevalence and nature of interactions between captive great apes and various indigenous wildlife species that range into their enclosures in North America. Our hypotheses were threefold: (a) facilities housing chimpanzees will report the most frequent and most aggressive interactions with local wildlife; (b) facilities housing orangutans and bonobos will report intermediate frequencies of these interactions with low levels of aggression and killing; and (c) facilities housing gorillas will report the lowest frequency of interactions and no reports of killing local wildlife. Chimpanzees and bonobos demonstrated the most aggressive behavior toward wildlife, which matched our predictions for chimpanzees, but not bonobos. This fits well with expectations for chimpanzees based on their natural history of hunting and consuming prey in wild settings, and also supports new field data on bonobos. Captive gorillas and orangutans were reported to be much less likely to chase, catch and kill wildlife than chimpanzees and bonobos. Gorillas were the least likely to engage in aggressive interactions with local wildlife, matching our predictions based on natural history. However unlike wild gorillas, captive gorillas were reported to kill (and in one case, eat) local wildlife. These results suggest that some behavioral patterns seen in captive groups of apes may be useful for modeling corresponding activities in the wild that may not be as easily observed and quantified. Furthermore, the data highlight the potential for disease transmission in some captive settings, and we outline the associated implications for ape health and safety.

The authors wish to thank all zoos who participated in this study. The full results are published in:
Ross SR, Holmes AN, Lonsdorf EV. 2009. Interactions Between Zoo-Housed Great Apes and Local Wildlife. American Journal of Primatology 71(6):458-465.