Outbreaks of house mouse (Mus spp.) populations are common in agricultural regions in Australia; however, examples in the US are limited to California (1920's and 1960's) and Florida (1999).  In Florida, restoration of 3,200 ha of former muck farms by a state agency was claimed to have resulted in an explosion of house mouse numbers on adjacent private lands.  Management actions began in 2001 to mitigate population growth of house mice.  Muck farms are mowed several times per year and plowed strips maintained on field margins and on boundaries between public and private land.  In 2006, a minor outbreak of house mice occurred on private lands.  Our research asked:  1) does mowing reduce house mice numbers, and 2) do house mice cross plowed strips.  Two 10 ha fields were selected for study.  In experiment 1, six bocks (each 1.6 ha) were randomly assigned to be mowed (n = 3) or undisturbed (n = 3).  Trapping grids were centered in each block.  Two regular Sherman live traps were placed at each of 25 trap stations.  A plowed strip divided each grid and block.  Traps were opened once per week for 21 weeks beginning in March 2008.  Experiment 2 was essentially a replicate of experiment 1 without plowed strips.

Results/Conclusions   House mice were found to be present at low but relatively stable numbers on cut and uncut fields of experiments 1 and 2.  In experiment 1, 46 captures were recorded on uncut grids and 23 on cut grids. Total captures in experiment 2 were 16 on three cut grids and 9 on uncut grids.  Pooling the data from the experiments showed the same relative number of individual house mice (excluding recaptures) were marked on six cut grids (n = 32) as on six uncut grids (n = 31).    Four tagged house mice crossed plowed strips; three of the four crossed a second time.  We conclude mowing of these fields does not result in a meaningful reduction of house mice numbers during spring and summer.  House mice crossed the plowed strips.  A cost analysis of the current management practices should be part of the adaptive management strategy to mitigate future changes in house mouse abundance on the former muck farms.