Investigating the impact of removing rabbit harbour on animal and vegetation dynamics Cottonvale Project Report 2007-2013

Abstract

The field study reported here documented differences between sites that were either side of the Darling Downs Moreton Rabbit Board fence: one side had a long history of rabbit exclusion with few rabbits present whereas the other side had higher rabbit numbers over time.
There were marked differences in the flora and fauna on either side of the fence, particularly rabbit abundance and pasture biomass. This difference reflected the long period of separation of the two areas by the DDMRB fence with differences in rabbit abundance as well as possible differences in general grazing management.
The control of rabbit numbers on the infested side of the fence did not improve pasture condition to a state similar to that in the rabbit free area during the relatively short period of this study. Recent reviews and simulation studies of the pasture response to changes in grazing management (including changing in grazing pressure) have shown that pastures may takes many years to respond to even quite large reductions in grazing pressure (Hunt et al. 2014, Scanlan et al. 2014). Any positive impact of reduced rabbit density on the infested side will require a much longer time frame for any measureable improvement could be recorded and will depend on the general grazing management of the area.
Small sample size precluded conclusively comparing rabbit survival on either side of the fence. This needs further investigation, particularly the effects on rabbit survival of those harbouring above ground compared with those living in warren systems. Similarly, reproductive output and recruitment appeared better where warrens were available, but this needs further testing in this environment with more data before more definitive conclusions can be made.