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Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered., Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy., Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species., Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation., Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife contraception, managers may need to consider the possibility that many species and populations can compensate for reduction in fecundity, and this could minimize any reduction in population growth rate. [ABSTRACT FROM AUTHOR]

The article outlines the curriculum for an introductory course in data-model assimilation to train students of ecology in the U.S. It reveals that the procedural emphasis of introductory material in statistics has been replaced by this course with an emphasis on principles needed to develop models of ecological systems, focusing models of data with models of ecological processes. It also concludes that this course is essential for students to create analyses for research problems.

1. The gain function describes the amount of food consumed in a patch as a function of patch residence time. Gain functions play a central role in foraging theory but alternative functional forms portraying dynamics of gain have not been evaluated. We evaluated the strength of evidence in the data for alternative gain functions of mule deer (Odocoileus hemionus, Rafinesque 1817) and blue duikers (Cephalophus monticola, Blythe 1848) feeding in patches composed of different plant species and plant sizes.2. Gain functions decelerated with patch residence time, but there was considerable variation among individual animals and patch types in the nature of this response. Asymptotic and piecewise-linear models received the greatest support in the data.3. Deceleration in gain was caused by a composite of effects that retarded instantaneous intake rate, including reductions in bite mass and increases in bite interval (time between successive bites). Bite interval increased as a result of increases in processing time of accumulated forage in the mouth, rather than increases in time allocated to cropping.4. We demonstrated that unwarranted assumptions about the shape of gain functions can have profound effects on predictions of patch models. Predictions of the classical patch model using purely asymptotic gain functions contrasted sharply with predictions of model-averaged gain functions that were supported by the data.Journal of Animal Ecology(2005)74, 181–189doi: 10.1111/j.1365-2656.2005.00911.x [ABSTRACT FROM AUTHOR]