Hypotheses on the Effects of Wolf PredationAbstract: This article discusses four hypotheses to explain the effects of wolf predation on large ungulate prey populations. The four proposed hypotheses examined are the predation-limiting hypothesis, the predation-regulating hypothesis, the predator pit hypothesis, and the stable limit cycle hypothesis. There is much research literature discussing how these hypotheses can be used to interpret various data sets obtained from field studies. It was concluded that the limiting predation hypothesis fits most case studies, but that further research is needed to account for relationships between multiple predators and multiple prey. The effects of predation can have a huge impact on the ecological organization and structure of communities. Predation processes affect virtually every species in one way or another. Predation can be defined as when members of one species eat (and/or kill) those of another species. The specific type of predation among wolves and large ungulates involves carnivores preying on herbivores. Predation can have many possible effects on the interrelationships between populations. To trace any correlations between the effects of these predator-prey interactions, long-term studies and statistical analyzes of large data sets representative of populations as a whole are needed. Predation could limit the distribution of prey and decrease its abundance. This limitation may be desirable in the case of harmful species, or undesirable for some individuals as in the case of game or endangered species. Predation can also act as a major selective force. The effects of predator-prey coevolution can explain many evolutionary adaptations in both predator and prey species. The effects of wolf predation on large ungulate species have proven controversial and elusive. Many different models have been proposed to describe the processes operating on populations affected by wolf predation. Some of the proposed mechanisms include the predation limitation hypothesis, the predation regulation hypothesis, the predator pit hypothesis, and the stable limit cycle hypothesis (Boutin 1992). The purpose of this article is to evaluate empirical data on population dynamics and attempt to determine whether one of the four hypotheses is a better model of the effects of wolf predation on ungulate population density. The limiting predation hypothesis proposes that predation is the primary factor limiting prey density. . In this non-equilibrium model, recurring fluctuations in the prey population occur. This implies that the prey population does not return to a particular equilibrium after the deviation. The predation limitation hypothesis implies a density-independent mechanism. The mechanism could apply to one-prey – one-predator systems (Boutin 1992). This hypothesis predicts that prey losses due to predation will be large enough to halt the prey population