Each year, with the help of numerous partners across thirteen states and Mexico, RiversEdge West produces an annual distribution map that notes the presence and absence of Diorhabda spp. from sampling sites across the west.

 

These data in no way represent all locations where the tamarisk beetle may exist, but give a broad perspective of beetle dispersal, providing land managers with information that may help with their integrated pest management plans, restoration strategies, and funding opportunities. If you would like to track the tamarisk beetle and to aid in data collection for the largest ongoing ecological experiment in North America, please visit our tamarisk beetle monitoring program page or contact Ben Bloodworth directly at bbloodworth@RiversEdgeWest.org.

 

In 2018, tamarisk beetle populations rebounded in SE Utah and SW Colorado, remained low (or absent) across Texas and the Plains states, and stayed fairly constant everywhere else.

 

There was a significant end-of-season southerly jump in the lower Colorado River Basin, where beetles were found at Imperial National Wildlife Refuge in mid-October. This is the farthest south that beetles have been seen in the CRB and further study is planned to determine whether this population can survive in this area.

 

Monitoring is proving to be more and more important as the beetle has not been present in the system for long and the dynamics of population movement and stability are not yet understood.

 

If you see areas on this map where you believe data are missing (or incorrect), please let Ben Bloodworth know by contacting bbloodworth@riversedgewest.org.  Thank you to all of our many partners for providing the data represented in this year's map!  

 

The production of the Annual Tamarisk Beetle Distribution Map is generously funded by a grant from the Walton Family Foundation.