4 Proportional changes in buffalo population in the five zones of the Serengeti at different times relative to the starting number in 1970. Ninety-five percent confidence intervals were calculated (largest was 0.12%) but were too small to show Spatial population dynamics model Details of the model (Eq. 1) can be found in Table 1. In our basic model configuration we assumed that the carrying capacity of a zone was proportional to the area and rainfall
(Eq. 3). The second model included the same hunting effort in each zone of the park with no lion predation and no drought. The third model included lion predation https://www.selleckchem.com/products/oligomycin-a.html (Eq. 5) but no hunting effort and no drought effect. These first three models fitted the data poorly. In model 4 hunting differed in each zone but had no lion predation and the fit of the model improved greatly. Model 5 was similar to model 4 but included the mortality from the 1993 drought (Eq. 1) and again the fit of the model improved. In model 6 we allowed the carrying capacity in the far east to be different from that of other areas (for the reasons explained above that resources differed), and this provided another significant improvement in fit. Again building
on model 6, in model 7 we included the impact of lion predation and this too provided an improvement. Thus, the model incorporating https://www.selleckchem.com/products/ABT-263.html unequal hunting effort, survival rates resulting from drought, carrying capacity in the far east estimated separately, and lion predation provided the best fit to the census data (Fig. 4). Using the likelihood ratio model 7 would be the preferred Idelalisib price model. Table 1 Candidate models of buffalo population changes over the last 50 years in the five regions
of the Serengeti Model Model description NegLLa # Parameters AICc 1 Equal k in all zones, no hunting, lions or drought 91.9 7 200.2 2 Equal k, equal hunting in all zones, no lions or drought 75.8 8 170.7 3 Equal k, lion predation, no hunting or drought 77.9 8 174.9 4 Equal k, hunting different by zone (v a estimated), no lions or drought 37.1 12 105.6 5 Equal k, hunting different by zone (v a estimated), drought included (S1993 estimated), no lions 16.0 13 66.8 6 K different for far east, hunting different by zone (v a estimated), drought included (S1993 estimated), no lions 13.7 14 65.9 7 K different for far east, hunting different by zone (v a estimated), drought included (S1993 estimated), lion predation included 10.7 15 63.7 a NegLL IGF-1R inhibitor negative log likelihood The models are defined by the variables that drive population dynamics. The best model (lowest NegLL) is shown in bold Final model parameter estimates The model that explained the most variation in population across the zones was model 7 (Fig. 5). Using this model we estimated that the north had the highest intensity of hunting with the exploitation rate in 1982 (the worst year for hunting) being 31%.