The Alberta portion of the forecast is based on surveys taken at approximately 1,300 sites throughout Alberta from the end of July to the beginning of August, the time of year when grasshoppers normally breed.
Surveyors measure numbers of adult grasshoppers to estimate numbers for the following year.
Weather, condition of vegetation, availability of egg-laying sites and the presence of grasshoppers during the previous summer are all factors taken into consideration when estimating the severity of grasshopper infestations. For grasshopper populations to increase, weather conditions should be warm but with low plant-available moisture. A warm, dry fall can enhance embryonic development, while overwintering eggs have an increased chance of survival during a mild winter. Grasshopper egg and hatchling survival can be reduced in extreme moisture or drought conditions. Some counties can expect to see reduced numbers from last year, while other counties will see higher numbers.