Environmental changes and temporal distribution of order Rodentia in North-East Brazil, and its link to the El Nino Southern Oscillation and drought in the region

摘要

Between 1978 and 2010 in the Low San Francisco Sergipano ("LSFS") North-East Brazil ("NEB") region, there have been outbreaks of rodent plagues with an irregular temporal scale but in the same spatial scale, where rats have attacked the floodplain rice fields. Rats constitute a serious problem, insofar as they affect rice growing in this region causing massive economic losses. "El Nino" (EN) has a significant impact on animal communities and its effects on NEB are most often associated with years of drought throughout that region, which tested serious environment changes in the 1970s. The genera and species identified in the paper are Holochilus sicureus, which is predominant in the LSFS, Oryzomys sublavus, Rattus spp., and Nectomys sp. This comparative study of the plague years suggest that the temporal scale for the rat plague is related to the El Nino/Southern Oscillation (ENSO) years and climatic conditions in the dry season in the NEB region.