Sheep Mortality in the US - The Facts

"SEVERAL STUDIES have been done comparing the perceived threat of predator (wolves, coyotes, carrion and hooded crows, and foxes) by sheep-men and the actual threat these predators posed. All such studies have found the risks to be greatly exaggerated, and that predators took far less livestock than they were blamed for. Animal Damage control, a division of the US Department of Agriculture, presented a great deal of information on this in a 1993 report ["Supplement to the Draft Environmental Impact Statement", USDA]. This report compared estimated costs of predation (by all predators) from a variety of sources with the actual cost of predation (in $US) verified by Animal Damage Control. The table below details the section of the report dealing with sheep."

State Actual Loss
Estimated Loss
Colorado 157,903 1,873,000 +1186%
Idaho 72,450 1,749,000 +241%
Montana 148,420 1,375,000 +926%
Nebraska 20,004 384,000 +1915%
S. Dakota 95,534 509,000 +532%
Texas 133,490 2,432,000 +1821%
Utah 200,764 4,730,200 +2356%
Wyoming 122,350 2,468,000 +2017%
Average over-reporting across all states: +1374%

"The same report also had a detailed survey of livestock producers and their losses to both predation and other causes. It must be noted that as a producer survey, these losses were not confirmed and if anything are overestimates. The condensed data regarding sheep and lambs is presented in the following table."

No. of States in the US raising sheep 41
No. of these States with resident fox populations 39
No. reporting any sheep/lamb loss due to foxes 17
No. of states with > 100 sheep/lambs lost to foxes 4
No. of sheep/lambs lost to all predators 489,500
No. of sheep/lambs lost to other natural causes 1,328,400
No. of sheep/lambs lost to all causes (inc. predators) 1,817,900
No. of sheep/lambs lost to foxes 12,800
No. of fox kills as a % of all predator kills 2.6%
No. of fox kills as a % of all deaths 0.7%

"Thus in the United States, losses to foxes in the vast majority of states were trivial and mortality due to foxes was at best less than 1 per cent of total sheep mortality. This is despite the fact that almost no areas in the US attempt to control foxes in the way that many parts of England do.

"The state of California is an interesting case. The native subspecies of red fox (Vulpes vulpes necator, the Sierra Nevada Red Fox) is very rare indeed and found only in a tiny area of the state. However foxes that escaped from fur farms in the Sacramento area (near the state's centre) during the 1920s, have expanded their range to cover the majority of the state, leaving California with a thriving fox population. Laws originally passed to protect the native sierra Nevada Red Fox have never been amended, and thus red foxes are not legally hunted or trapped anywhere in the state of California and, in fact, are afforded total protection.

"Despite this, fox problems with livestock have been minimal. Even though California is second only to Texas in the dollar value of sheep produced, fewer than 100 lambs were killed by foxes in the entire state."

Extract from a 1997 article by Prof. Cris Waller headed "The Case Against Fox Control".

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