Background Theory predicts that the logarithm of mean extinction times will scale with patch carrying capacity. Although previous results are consistent with this theory over a five-fold change in carrying capacity (Drake & Griffen 2008), patch sizes in nature vary by orders of magnitude and the generality of this prediction has not been tested. This study seeks to document the pattern of extinction times in a series of artificial habitats that vary in size over 9 orders of magnitude.
Design Modular habitats have been specially constructed for this study from 1.25″ diameter acrylic tubing. Populations were inoculated with 5 individuals of Daphnia magna reared on suspended Spirulina. The experiment was set up in Spring 2012 with a regression design comprising a gradient of patch sizes (10 levels) each replicated 6-20 times. Populations are monitored daily for extinction and censused weekly to obtain population size. It is completely unknown how long this experiment will last, but back-of-the-envelope calculations suggest that the average population in the largest habitats will go extinct in Fall 2016.