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Archive for December 6, 2019

Coyote Breeding Season Beginning

Female Eastern Coyotes only experience estrus once per year for up to ten days and male coyotes only produce sperm during the time females are receptive.  This usually occurs sometime between late December through March.

One unusual aspect of the coyote breeding season is the coyote’s ability to change its breeding habits according to its population status. When their population is threatened and/or pressured, coyote litter sizes go up. They use their howls and yipping to assess coyote populations — if their howls are not answered by other packs, it triggers a response that produces large litters. (I have yet to understand the biological specifics of  this adaptation.)

The normal size of a coyote litter is five to six pups. When their populations are suppressed, their litters get up as high as 12 to 16 pups. Research shows that the number of coyotes in a given area can be reduced by 70 percent but the next summer their population will be back to the original number.

(Photo: blood droplets where a female coyote in estrus urinated. Photo taken 12/4/19)

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