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Trends and Management of Wolf-Livestock Conflicts in Minnesota

Depredations


During 1975-86, we investigated 600 complaints of depredations on livestock and verified 328 (55%) at 240 farms (farms counted more than once if they experienced depredations in multiple years). Verified complaints averaged 30 per year, and the number of farms where depredations were verified averaged 21 (Fig. 3). From 1979 to 1986 the number of verified complaints averaged 33 annually, and the number of farms with verified complaints averaged 24. About 0.33% of the farms within the range of the wolf in Minnesota were affected annually, assuming a total of 7,200 farms.

Cattle, sheep, and turkeys were the most common domestic prey during each year of the study (Table 1). Complaints of depredations on those three livestock types composed 88% of all verified complaints (Table 2). An average of 23 cattle, 49 sheep, and 173 turkeys were verified as lost to wolves per year from 1979 through 1986. Although complaints involving cattle were the most common, they were usually characterized by fewer losses per complaint (Table 2). The average number of individuals killed or wounded per verified complaint was clearly related to size (vulnerability) and abundance, ranging from 1.2 for cattle to 53.5 for turkeys (Table 2). There was greater agreement between numbers claimed lost and numbers verified lost for turkeys than for sheep, and especially for cattle (Table 2). The difference probably relates to the relative difficulty of finding remains of calves in the wooded areas where they are often pastured in spring and summer, whereas sheep and turkeys are more often killed in open (nonwooded) pastures. Thirty-nine percent of the 570 cattle claimed killed by wolves were missing cattle. Actual loss of cattle and other livestock to wolves lies between the verified and claimed loss figures (Fig. 2).

Table 2. Comparison of depredation characteristics for the most common domestic prey of wolves in Minnesota: cattle, sheep, and turkeys.

Characteristic
Cattle
Sheep
Turkeys
Percent of all verified complaints
54
27
7
Ratio of claimed killed (in relation to cattle)
1.00
1.28
3.82
Ratio of verified killed (in relation to cattle)
1.00
2.14
7.60
Percent of number of individuals claimed lost that were verified
31
52
62
Mean number of individuals killed or wounded per verified complaint
1.20
4.40
53.50

Calves constituted 87% of the cattle claimed and 82% of the cattle verified lost, indicating a clear selection by wolves for calves over adult cattle, which are more difficult to kill. This result is comparable to findings in western Canada, where 62 and 66% of the cattle killed by wolves in Alberta and British Columbia were calves (Gunson 1983).

The amount of compensation paid to farmers remained fairly stable from 1977 to 1986, averaging $21,228 (high-$38,606, low-$8,668) per year, even though public awareness of the program probably increased throughout the period (Table 3). The number of farmers who received compensation from the MDA for livestock destroyed by wolves statewide (Table 3) was similar to the number of farms having verified complaints. We believe that farmers were motivated to report claims for possible compensation and that they missed few opportunities to do so. Any complaint to the MDA was relayed to our program. The number of livestock losses authorized for payment by the MDA often slightly exceeded our figures for animals verified as lost to wolves because the MDA used more liberal verification criteria. Compensation was sometimes paid for missing animals after complaints that other livestock were suspected or confirmed killed by wolves, or if wolf depredations had been confirmed at the same farm in previous years.


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