I have a lot of quibbles with Dan Flores’s book, Coyote America. Among them is a contention that coyotes howl because it allows them to “take a census.” If no other coyotes howl back, the females wind up releasing more ova and having larger litters. This description, which Flores calls an “autogenic trait,” cannot be found anywhere in the coyote literature. His account is not described in the book, but it is mentioned in his interview with National Geographic and on The Joe Rogan Experience.
I have no idea where Flores got this idea, but it’s not really what happens. The literature on why coyotes have larger litters in areas where they have been heavily hunted says that the larger litter sizes are associated with better access to food resources. The best-known paper on this issue comes from Eric Gese, a researcher with the USDA, who studied coyote population dynamics in an area of Colorado.
Gese contends that what happens with coyotes in pressured areas is that the surviving females are healthier, simply because they have access to more food resources. This greater health causes them to release more ova during the estrus cycle, and this increase in ova results in greater litter sizes.
It is not because the coyotes are taking census and can somehow magically figure out that they should produce more young. It is simply that the coyote females’ own bodies respond to greater food resources by becoming more fertile.
What has possibly evolved in coyotes is that they have a tendency to become significantly more fertile when the females are at their most healthy. This is a great trait for a mesopredator to have.
After all, coyotes evolved in North America with dire wolves and a host of large cats breathing down their necks. Natural selection favored those that could reproduce quickly if populations were dropped dramatically.
But it’s not because of some “autogenic trait.” It is simply how coyote populations expand as mesopredators with increased or decreased access to prey.
So yeah, my take on Coyote America is that it is mostly a science fiction book. Not only does he mess up the exact genetic difference between a wolf and a coyote, which is not equivalent to the genetic difference between a human and an orangutan (as he claims), he also messes up that coyotes really do hunt down and kill cats and eat them. They are not just killing a competitor. They are using cats as a food resource.
This was a book I was so looking forward to reading. It got good press, but the actual science in it was so lacking.
One of my favorite books about coyotes is God’s Dog: A Celebration of the North American Coyote by Hope Ryden. She spent several years studying Western coyotes in the field & while the book is a bit dated, her work is still valid. Much of what we have learned about coyotes (in particular, the Eastern coyote, which was still largely an enigma then) since her book was published can be viewed as adding to her observations, rather than refuting them.
I’m not a big fan of Dan Flores’s books in general. It’s one thing to extrapolate ideas from known behaviors and present such ideas as speculation; it’s quite another to present one’s own untested idea as fact. He’s done that in his other books, for instance in American Serengeti.
Increases in litter sizes in response to predation is a phenomenon that has been recognized for centuries among small & mid-sized mammalian wildlife. I almost said “small & mid-sized predators”, but then I remembered pigs. And deer. And rabbits. And cats. And pariah dogs. And. And. And.
There’s no need to look for some esoteric “autogenic trait” to explain it. Decreased numbers of animals using the same resources equals more resources per individual equals better overall health per individual. Better overall health probably does influence ovulation: a well-fed and less-stressed adult female of a given species is likely to produce more and more viable ova than one that is malnourished & stressed.
I have read that book! It’s a lot better than the Flores book. The best coyote book is “Coyote Settles the South” by John Lane.
I’ve read one of Lane’s other books, Circling Home. I liked that one a lot. Coyote Settles the South is on my “to read” list.
Another good book that also addresses the coyote in the South (though tangentially) is Mad Dogs: The New Rabies Epidemic, by Donald Finley (from Texas A & M University Press).