CHAPTER 9 
Ethological Approaches 
Ethology is the study of species-typical patterns of behavior — with a focus on uncovering the 
causes, function, development, and evolutionary significance of such behavior. (See Novak et 
al., 1998, for a more detailed examination of this topic.) Ethological research differs from 
most behavioral research in that the animal is neither a model nor a surrogate for another 
species. Ethology includes a wider range of species. For many of these species, there is little 
information on optimal housing and husbandry. Instead, unique environments are designed 
by the researcher to elicit and maintain the behavior patterns of interest. Such environments 
frequently require alterations in husbandry practices. The ILAR Report (ILAR, 1996) permits 
naturalistic environments. In some instances, however, 1ACUC approval of exceptions may be 
required. The sections below identify possible welfare issues pertaining to ethological 
research. 
PASSIVE OBSERVATION 
Some ethologists study animals to learn about habitat utilization, foraging strategies, 
breeding patterns, and social organization. Care should be taken to minimize harmful effects 
of the observation process on other populations living in the setting or being a vector of 
disease, thereby increasing the risk of predation in prey species or reducing capture rates in 
predatory species. 
Difficulty in observing a free-ranging population may require provisioning (augmenting the 
natural food supply) to bring animals close to the observer. The provisioned material should 
minimize possible dietary imbalances. The subject population may be exposed to models or to 
other living animals, or their odors or vocalizations. Because provisioning may artificially 
increase population densities, the researcher must be alert to heightened aggression and 
ultimately lowered reproduction. When the study is over, loss of provisioning may result in a 
higher mortality because the environment can no longer support the expanded population. 
These effects may be partially controlled by considering the frequency and length of the 
provisioning period as well as the actual distribution of food in terms of the area covered. 
Whenever the habitat is altered, there may be changes in breeding rates or in the risk ot 
predation. When the exposure involves a living animal, special techniques may be required 
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