Experimental population suppression of Richardson's ground squirrels (Spermophilus richardsonii) in Alberta

Richardson's ground squirrel is one of the most economically harmful rodents in east central Alberta. In an effort to develop an effective, safe, economical and practical method of long-term population control over large areas, experimental field testing was begun in 1970 to evaluate a variety of potential control techniques. Although tests with a machine bait applicator proved unsuccessful due to the unique soil structure, its potential in other areas of the province is discussed. Use of portable baiting stations is limited by the manufacturing and maintenance costs as well as the limited attractability of the stations. Attractability of the stations to ground squirrels was not increased with the use of reflector tops; however, it did have a repellent influence on raptors feeding in the area. Disposable baiting tubes appeared to have greater potential for large acreages and possible aerial application. Initial tests conducted with diethylstilbestrol and mestranol as chemosterilants are outlined. The potential of using techniques to regulate reproductive rate as opposed to increasing mortality rate is discussed. The potential of using amphetamines to reduce body weight and increase winter mortality during hibernation is also discussed