Many populations of organisms deplete their resources, causing population growth rates to decline as population density increases. I used the sawtoothed grain beetle, Oryzaephilus surinamensis (L.), as a model to gain insight into the mechanisms of population regulation. Eight experiments differentiated the effects of crowding and food depletion on dispersal, mortality, and reproduction. Generally, food depletion caused increased mortality of immature beetles, sharply reduced oviposition, and increased adult dispersal. Rates of birth and death were both negative exponential functions of increasing density. The experiments quantify the trade-off between food and area in population regulation. These trade-offs varied with initial abundance of larvae and adults and show the risk of ignoring abundances of any life stages when characterizing vital rates. I contrast population regulation of O. surinamensis with Tribolium sp., and suggest O. surinamensis is a good alternative for experiments on population dynamics because of better mobility and shorter development time.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.