Using climate data to predict grizzly bear litter size

Harold D. Picton; Richard R. Knight

doi:10.2307/3872804

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Using climate data to predict grizzly bear litter size

Harold D. Picton·Richard R. Knight

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Abstract

A 5-year double-bind test was conducted to test the predictive capability of a previously published (Picton 1978) regression (Y= 2.01 + 0.042 x ), which described the relationship between the littler size of grizzly bears ( Ursus arctos horribilis ) and an index of climate plus carrion availability (climate-carrion index). This regression showed an efficient in excess of 99% in predicting the observed grizzly bear littler size. The predictions made using the climate-carrion index had a mean absolute error of less than 25% of forecasts using other methods. The updated climate-carrion index regression, which includes all of the 16 years for which data are available, is Y= 2.009 + 0.042 x ( r = 0.078; P < 0.01; N = 16). We concluded that the climate-carrion index can be a helpful tool in predicting grizzly bear littler size. The relation of this information to the effects of the closure of Yellowstone Park garbage dumps is discussed.

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Harold D. Picton, Richard R. Knight. 1986. Using climate data to predict grizzly bear litter size. https://doi.org/10.2307/3872804

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