Predicted grasshopper development (Jun 07, 2018; Wk 05)

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of June 4, 2018, predicted hatch was 51% (31% last week; long term average was 11%).  Hatch is predicted to be nearly complete in southeast AB and southern MB (Fig. 1). Grasshopper populations are primarily in the first instar (Fig. 2).

Figure 1. Grasshopper hatch (%) based on model simulations, for April 1-June 4, 2018.

Figure 2.  Percent of grasshopper population that is in the first instar, based on model simulations, for April 1-June 4, 2018.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Saskatchewan Agriculture, Alberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new "Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide" as an English-enhanced or French-enhanced version.