Scat samples put Seattle's coyote density at nine times Washington's wildlands

Divide 842 scats by 213 identified animals and you get just under four samples per coyote ^[1]. That ratio is the engine of the estimate. Density was calculated from how often a collection trip turned up a second or third deposit from an animal already on the list ^[4]. Re-encounter the same individuals often and the population they came from is small; hardly ever re-encounter them and it is large, or the sampling was too thin to say either way.

The direction of the human-density effect is the part worth sitting with. Inside Seattle, places with more people held fewer coyotes, and yet the city as a whole carried far more coyotes than the sparsely populated study areas near Winthrop and Chewelah ^[6][3]. Both can hold, because they are different comparisons: one is a gradient within a single city, the other is a city against forest, and the second is where mortality does the work. Wolves and mountain lions hunt coyotes in wild country, and rural landowners shoot them to protect livestock ^[8]. In Seattle, cars and disease are the regular killers ^[9].

For scale beyond Washington, Chicago is estimated to hold about 4,000 coyotes, and Los Angeles urban density has been reported as at least seven times wild-area levels ^[11]. Seattle's nine is the larger figure ^[2], but "at least seven" is a floor rather than a point estimate, and the wildland baselines are different places, so the two numbers do not rank the cities.

What the study fixes is a level, not a direction. Prugh says long-term population data is limited and the case for rising numbers over recent decades is anecdotal, if overwhelming ^[13], and the absence of formal data is precisely what has made trends hard to track ^[12]. Nor does it tell you whether the city is full: coyotes are territorial and fight over turf, which caps numbers where larger predators are absent, and Prugh says she does not know whether Seattle has reached that ceiling ^[14]. The rabbit explanation stays an explanation. She suspects rabbit density predicts coyotes better than human density does, and says there is not enough data to test it ^[16], while Seattle's rabbit boom of recent decades may have helped draw coyotes in ^[17].

The practical value is that scat collection can be repeated. Run the same design again in a few years and Seattle has a slope rather than an impression, which is the quantity a removal or tolerance decision actually turns on ^[12].