Combining Occurrence and Habitat Suitability Data Improve Conservation Guidance for the Giant Kangaroo Rat

Abstract

ABSTRACTIdentifying high‐quality habitat (i.e., areas with resources and conditions suitable to support long‐term species persistence) is a priority for conservation, but estimating habitat quality is expensive and time consuming. Instead managers often rely on occurrence data or models of habitat suitability, but these data are only proximally related to individual and population persistence on the landscape. In most habitat suitability modeling studies, researchers treat the model as a hypothesis and the occurrence data as the truth. But occurrence does not always correlate with habitat as expected; therefore, occurrence data may be unreliable. We propose that suitability models and occurrence data be given equal weight to highlight areas of disagreement for future demographic study. To highlight this approach, we used the giant kangaroo rat (Dipodomys ingens) as a case study because their distinct burrow mounds allow for remote monitoring of short‐term presence and long‐term persistence. We conducted trapping, manned aerial surveys, and aerial imagery surveys in the San Joaquin Desert in California, USA, between 2001 and 2017 and compared the results to an existing habitat suitability model to provide estimates of long‐term persistence based on the presence of burrow mounds made by giant kangaroo rats. We treated areas of positive agreement as priorities for habitat conservation and areas of negative agreement as areas managers could ignore. Remaining areas should be prioritized for additional occupancy and demographic studies. From an initial area of 17,385 km2, we identified 668 km2of currently occupied high‐quality habitat. Of this, just 135 km2was on private land and therefore requiring protection. We classified 1,498 km2(8.6%) for additional research. Of that area, 744 km2was flagged for additional occupancy surveys. Our 3 data sets disagreed over 754 km2, suggesting a need for further demographic studies to reveal important population‐habitat relationships for the species in those areas. This approach can be useful as part of any habitat conservation exercise for prioritizing protection or targeting future demographic studies. © 2021 The Wildlife Society.