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Results Page 4 of 8 The effectiveness and costs of egg removal as population control procedure were measured during the 1990 -96 period. Nest searching by 2- person teams was done on 3 type -5 wetlands totaling 278 ha. Searching was done by walking, wading, and canoeing. When a nest was found, the clutch size was recorded, and the stage of incubation determined from egg laying or by floatation. To prevent renesting (Cooper 1978), egg removal was delayed until at least the 18th day of incubation. We located 342 nests and removed 1,745 eggs over the 7 -year period (Table 3). Two of the 3 sites were fenced, thus the proportion of nests not found could be estimated from the broods observed. Over the period, 8 broods were observed. Assuming a 75% nest success (Sayler 1978), we estimated that 97% nests were discovered. Table 2. Ranking of effectiveness of short -term goose redistribution methods used in the Metropolitan Twin Cities, 1982 -1996. Method N Ranking' Decoy -dead goose 1 L Decoy -swan 156 L Feeding Ban 94 L Fencing- electric 4 H Fencing - permanent 15 H Fencing- Temporary 182 M Habitat modification 15 L Harassing -dog 8 M, Harassing - people 310 L Harassing - vehicle 93 L Live swan 7 L Methyl anthranilateb 3 L 'Id= low effectiveness, M= moderately effective, and H= highly effective. bRejects -It.f Table 3. Canada goose nests and eggs found and time spent searching by two - person teams, Gun Club Lake, Mother Lake, and Wood Lake, Twin Cities, Minnesota 1990 -1996. Year Nests Eggs Hours Eggs /Hour 1990 39 202 96 2.1 1991 43 218 119 1.8 1992 38 195 125 1.6 1993 45 216 175 1.2 1994 42 162 144 1.1 1995 110 626 171 3.6 1996 25 126 176 0.7 Total /Mean 342 1,745 1,006 1.7 Trap and Relocate A total of 40,515 flightless geese was trapped and removed from the Twin Cities between 1982 -38- http: / /www.fw.umn.edu /research /goose /html /urban /manage6.html 4/7/00