Separating Fact from Fiction: Are Roadrunners Impacting Quail Populations?
southwestern United States. Photo by Becky Ruzicka.
“Roadrunners are drawn to baby quail like seafood addicts are drawn to popcorn shrimp” (Bowers 2013).
“The ranch manager insisted that all of the roadrunners needed to be destroyed due to their tendency to prey on young quail and eat the [sic] their eggs” (Roadrunners bad for quail? Myth of [sic] fact? 2013).
“[Anonymous] wants all coyotes and roadrunners dead. They eat quail & quail eggs, and have decimated the quail population over the last 4–6 years. We let the hogs and vultures eat ‘em” (Dead coyote and roadrunner (Freedom Of The Road) 2011).
The quotes above represent a small sample of the vitriol leveled at the greater roadrunner, Geococcyx californianus, for its alleged role in the decline of quail populations. Talk to anyone who spends time outside in areas where both roadrunners and quail are prevalent, and you will hear plenty of similar accounts: stories of roadrunners snatching quail chicks straight from under their mothers’ noses and raiding entire clutches from nests. To hear some folks tell it, these precocious predators are a major source of stress on multiple quail species, making roadrunners a sworn enemy of quail enthusiasts throughout Texas.
But how much truth is there to these claims? Do roadrunners actually depredate nests and broods, and if so, is it to such an extent that they can be accused of contributing to the quail decline? To answer these questions we first ought to follow the advice of Sun Tzu who implored, “Know your enemy.”
The greater roadrunner is a ground-dwelling bird common throughout much of the southwestern U.S. and Mexico, with the densest populations occurring in California, Arizona, New Mexico and Texas (Maxon 2005). It is the state bird of New Mexico and has several alternate monikers including chaparral cock, chaparral bird, snakebird, and — south of the border — paisano (Maxon 2005, Dobie 2006). U.S. Breeding Bird Survey data tells us that roadrunner populations have been relatively stable for decades, with a slight overall decline occurring between 1966 and 2001 punctuated by increases in specific areas, including the Chihuahuan Desert and South Texas brushland (Maxon 2005). Their Texas territory therefore overlaps more with scaled quail (Callipepla squamata) than with northern bobwhites (Colinus virginianus; Bryant 1916). Thanks to the birds’ highly adaptable and flexible nature, as well as anthropogenic landscape changes that worked in their favor, roadrunners have also undergone a rapid eastward expansion, extending their range approximately 500 miles into Kansas, Oklahoma, and East Texas just within the last century. This expansion means that people are seeing roadrunners — and seeing more roadrunners — in places where they may have been rare or nonexistent before.
horned lizard to her chick. Photo from Texas A&M AgriLife Extension.
So roadrunners are out there, and they are out in force. Perhaps the most important question, though, is what do they eat? There have been a few key studies that have attempted to provide an answer. InHabits and Food of the Roadrunner in California, 84 roadrunners were dissected to determine their typical diet makeup. The verdict was that insects constitute the vast majority of the roadrunner’s diet — up to 75% of stomach contents, with the remainder consisting primarily of lizards, small mammals, and some small birds. No quail were observed among the contents in this data set (Bryant 1916). An investigation by the Texas Parks and Wildlife Department concluded that insects were the primary food source for roadrunners in South Texas, but researchers also found the remains of 2 northern bobwhite quail chicks, a pyrrhuloxia (Cardinalis sinuatus), and even a juvenile greater roadrunner after examining 118 birds (Kazmaier et al. 1999). Other work has attempted to describe roadrunner food habits through direct observation and dissection of individuals that were in close proximity to quail during nesting and brood rearing periods. Once again, insects made up the majority (62%) of stomach contents in this case, along with other arthropods like tarantulas, centipedes and scorpions, as well as the requisite lizards and even part of a rattlesnake (Gorsuch 1932).
While they may not be a diet staple, it cannot be said that birds are safe from the roadrunner’s voracious appetite. Researcher Dale Zimmerman previously described the roadrunner’s propensity to take passerine bird species (songbirds) as prey. He has witnessed a paisano killing and eating an adult junco (Junco hyemalis) during a time when insects were still abundant. He also reports seeing roadrunners carrying recently killed birds in their beaks, as well as stalking and predating house sparrows (Passer domesticus) on at least 2 occasions. There are numerous bird species, including quail, mockingbirds, curve-billed thrashers, and scrub jays, which have been known to sound alarm calls or perform threat displays in the presence of roadrunners, implying that they are recognized as a threat (Zimmerman 1970). There is also anecdotal evidence on the other side of the fence, however, stating that roadrunners have been observed passively following Gambel’s quail broods with no acknowledgement by the parent, concerning themselves only with the grasshoppers and other insects that the quail were stirring up (Gorsuch 1932).
[See Video: Gambel’s and Roadrunner]
Little compelling evidence exists to suggest that roadrunners depredate quail nests to any significant degree. A 1997 study documented nearly 800 predation events on simulated turkey and quail nests and found that raccoons were by far the most active culprits, accounting for 80% of turkey nest predations and 91% of quail nest predations. Other common visitors included bobcats, gray foxes, and striped skunks (coyotes and feral pigs are also frequent nest predators but were relatively scarce in this research area). There were 3 occasions where roadrunners were photographed, but they were never caught raiding a nest (Hernández et al. 1997).
Texas Quail Index 2016 data set.
Wildlife biologist Dean Ransom, who has studied both roadrunners and quail, summarizes the situation as follows: “RR’s are opportunistic generalists that will eat whatever they can catch. It is far more economical to head to the ranch road and snag a horned lizard than to wander randomly trying to find a quail nest” (Ransom 2016). From time to time, roadrunners likely stumble upon and predate quail eggs and chicks, though scientific evidence suggests that it would be irresponsible to call them primary predators of quail or label them as the ringleader of the quail decline. Roadrunners may even be secret allies to quail: they are certainly known to eat rats and snakes, which are more active and well-established quail nest depredators than the roadrunners themselves (Bryant 1916). If you are still not convinced, bear in mind that, being a predatory bird, roadrunners are protected by law and killing one carries a $500 fine (Turner n.d.). Roadrunners have been saddled with a bad rap, but the truth is that quail have bigger problems than the chaparral cock.
To learn more about quail predators and nest depredation, check out these resources:
Blog articles:
YouTube videos:
Literature Cited
- Bowers, B. 2013. Roadrunners and Quail. birdingthebrookeandbeyond. <https://birdingthebrookeandbeyond.com/2013/05/08/roadrunners-and-quail/>. Accessed 12 Aug 2016.
- Bryant, H. C. 1916. Habits and Food of the Roadrunner in California. University of California Press.
- Dead coyote and roadrunner (Freedom Of The Road). 2011. <http://z3.invisionfree.com/Freedom_Of_The_Road/ar/t2687.htm>. Accessed 12 Aug 2016.
- Dobie, J. F. 2006. Chapter 2: The Roadrunner in Fact and Folk-Lore. Page 12 in. Folklore: In All of Us, In All We Do. Texas Folklore Society. <http://lib-ezproxy.tamu.edu:2048/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=tih&AN=36212308&site=eds-live>. Accessed 10 Aug 2016.
- Gorsuch, D. M. 1932. The Roadrunner. Arizona Wildlife 1–11.
- Hernández, F., D. Rollins, and R. Cantu. 1997. Evaluating evidence to identify ground-nest predators in west Texas. Wildlife Society Bulletin 25:826–831.
- Kazmaier, R. T., D. C. Ruthven, and D. R. Synatzske. 1999. Spring and Summer Diets of Greater Roadrunners in South Texas. Page 26 in. 1999 Wildlife Research Highlights Volume 4. Volume 4. Texas Parks and Wildlife Department. <https://tpwd.texas.gov/publications/pwdpubs/media/pwd_bk_w7000_0280_06_99.pdf>. Accessed 29 Aug 2016.
- Maxon, M. A. 2005. The Real Roadrunner. University of Oklahoma Press.
- Ransom, D. 2016. RE: Question about roadrunners and quail.
- Roadrunners bad for quail? Myth of fact? 2013. TexAgs. <http://texags.com/forums/34/topics/2319013>. Accessed 12 Aug 2016.
- Turner, L. D. n.d. Regulations Related to Predator Control in Game Management. Texas Parks and Wildlife Department. <http://texnat.tamu.edu/files/2010/09/021.pdf>. Accessed 10 Aug 2016.
- Zimmerman, D. A. 1970. Roadrunner predation on passerine birds. Condor 72:475–476.
Written by Amanda Gobeli, Texas A&M AgriLife Extension Associate
Originally published at wild-wonderings.blogspot.com.
