Seasonal fluctuations of small mammal and flea communities in a Ugandan plague focus: evidence to implicate Arvicanthis niloticus and Crocidura spp. as key hosts in Yersinia pestis transmission

Table 3 Best fit models of Arvicanthis niloticus abundance above 1300 m with climate and crop variables

Model	R ²	AIC	∆AIC	Model parameters	Parameter estimate
Climate variables only – Above 1300 m
1	0.50	−217.3	0	Precipitation – 6 month lag	−0.56
1	0.50	−217.3	0	Precipitation – 4 mo. Lag	0.37
2	0.48	−215.6	1.7	Precipitation – 6 mo. Lag	−1.4
2	0.48	−215.6	1.7	Mean temperature – 0 mo. lag	0.83
Climate and crop variable – Above 1300 m
1	0.69	−232.3	0	Maize/Millet harvest – 0 mo. lag	0.47
1	0.69	−232.3	0	Nut harvest – 4 mo. Lag	0.53
2	0.68	−231.0	1.3	Maize/Millet harvest – 0 mo. lag	0.51
2	0.68	−231.0	1.3	Bean harvest – 4 + 5 mo. Lag	0.51

Model r², AIC, and ∆AIC values and parameter estimates for all models with ∆AIC <2 and parameter estimates significant at an α = 0.05 confidence level. ∆AIC represents the difference between a model’s AIC value and the AIC value of the best fit overall model. Parameter estimate values are expressed as a change in abundance per 100 trap nights as a result of a 1°C increase in temperature, 100 mm increase in precipitation, or per each additional homestead at a trapping location harvesting a given crop.

ISSN: 1756-3305