Greater Roadrunner (Geococcyx californianus)

Photo by Peter Knapp

Prepared by: Pete Famolaro

Field Biologist, Sweetwater Authority

100 Lakeview Ave., Spring Valley, CA 91977.

RECOMMENDED CITATION:

Famolaro, P. 2002. Greater Roadrunner (Geococcyx californianus). In The Coastal Scrub and Chaparral Bird Conservation Plan: a strategy for protecting and managing coastal scrub and chaparral habitats and associated birds in California. California Partners in Flight. http://www.prbo.org/calpif/htmldocs/scrub.html

SHORTCUTS:

range map

references

SUBSPECIES STATUS:

Currently no recognized subspecies (Hughes, 1996, Pyle 1997).

MANAGEMENT STATUS:

No federal or state status. No other special status. Unitt (1984) indicates that roadrunners are habitat limited and have experienced a reduction in numbers due to urbanization.

DISTRIBUTION:

HISTORICAL DISTRIBUTION:

Common where suitable habitat exists (Grinnell and Miller 1944). Range occurs from south of the head of Sacramento Valley, west from the Nevada State line and Colorado River to coast or nearly so in central and southern sections, northwest from Mexican Boundary to Mendocino County, west of Sierra Nevada to Shasta County, and east of Sierra Nevada to northern Inyo County (Grinnell and Miller 1944). Greater roadrunner numbers reduced where extensive human settlement or overhunting has occurred (Grinnell and Miller 1944).

Once considered common in San Diego (Belding 1890 and Stephens 1919), roadrunners, although widespread in range, have undergone population reduction and local extirpation due to urban development (Unitt 1984). In Hughes (1996),"Extirpated from the Central Valley in n. California (McCaskie 1988), San Francisco Bay Area and coastal Marin Co. (Shuford 1992), Santa Barbara Co. (Lehman 1994); and San Diego Co. (Unitt 1984), and likely other s. California counties (Garett and Dunn 1981) where residential and agricultural development has been extensive." Roberson and Tenney (1993) report that the range of the Greater Roadrunner has retracted from coastal areas of Monterey County due to urbanization. Greater Roadrunners have been extirpated from the Point Lobos, Carmel Valley and the Monterey Peninsula.

CURRENT BREEDING DISTRIBUTION:

In California, roadrunners occur from the foothills of Sacramento Valley, Owens Valley in e. California, and widespread s. California up to 2,300 meters, (McCaskie et al. 1988, Small 1994 in Hughes 1996). Lovio (1996) observed roadrunners regularly occurring in coastal sage scrub adjacent to suburban development in the vicinity of Sweetwater Reservoir, San Diego Co. Nesting was also recorded. Regular occurrence and breeding was confirmed for the same area between 1995 and 2000 (Famolaro, field notes). In the late 1970's and early 1980's, Everette recorded nesting in dense cactus patches below the Sweetwater Resevoir Dam (Everette 1984).

Carlson found active nests on U.C Riverside Motte Rimrock Preserve, Perris, CA (field notes 1981, 1983, 1993, and 1996), San Jacinto Wildife Area and Temecula, Riverside Co.(field notes 1990), and San Bernardino Co.(field notes 1993). In Orange County, common resident of coastal and foothill coastal sage scrub, scrub/grasslands and chaparral, uncommon in the mountains. "Roadrunners are absent from many fragmented habitat patches" (Hamilton and Willik 1996).

Breeding Bird Atlases

Orange County BBA - Gallagher (1997) reports that roadrunners are fairly common residents of the coastal sage scrub, found from the Los Coyotes hills in northern Orange County to the hills above San Clemente in southern Orange County.

Monterey County BBA - Roberson and Tenney (1993) state that the Greater Roadrunner is a scarce local resident of xeric chaparral, native grasslands, oak savannas and riparian scrub on the margins of the Salinas Valley.

ECOLOGY:

AVERAGE TERRITORY SIZE:

Studies from s. California, Arizona, Texas indicate average territory size per pair ranging between 0.7 - 0.8 km diameter (27.9-49.6 hectares) (Bryant 1916, Calder 1967, and Folse 1974 in Hughes 1996).

TIME OF OCCURRENCE AND SEASONAL MOVEMENTS:

Year-round, non-migratory, resident (Hughes 1996).

FOOD HABITS:

FORAGING STRATEGY:

Roadrunners typical foraging habit is to hunt on the ground or in low stature vegetation (Beal 1978a and 1981 in Hughes 1996). They do appear to be quite opportunistic and creative in foraging strategy. Observations have also been made of them gleaning arthropods from leaves, ambushing prey at feeders (Wright 1973, Spofford 1976), nesting boxes (Green 1994), mist-nets (Barclay 1977), and birds in flight by knocking down low flying birds (Sutton 1940) (in Hughes 1996). They have taken young bats which fallen from roost or collided with cave walls (Herreid 1960 in Hughes 1996). Hunts by moving sporadically, stopping to scan for or flushing prey (Huhges 1996).

DIET:

Roadrunners are omnivorous, although diet is primarily (90%) animal food (Bryant 1916 in Hughes 1996). A variety of arthropods, lizards, snakes, rodents, bats, birds, eggs, and carion have all been taken as food (Hughes 1996). Grasshoppers comprise an important source (Bryant 1916 and Parmley 1982, in Cornett 2000). Fruit and seeds are consumed with seasonal availability (Bryant 1916 in Hughes 1986). Roadrunners have been hunted throughout the 20th century due to rumors of quail predation (Hughes 1996). Feeding studies show rare consumption of quail (Hughes 1996).

BREEDING HABITAT:

"Areas of mixed open ground and tracts of brush; arid, open land with scattered bushes or thickets; edges of chaparral, where adjoining sparsely vegetated grassland," mesquite, cholla, tuna cactus, catclaw, suma, buck-brush, and small-sized, thick-folliaged oak trees used for shade, safety-refuge, roosting and nesting, up to 7500 feet (Grinnelll and Miller 1944).

Arid and semi-arid open scrub (low to 50% cover) with brush layer 2-3 m high (Folse 1974). Nest usually located in isolated thicket of small trees and bushes, rather than extensive tracts of woody vegetation. Situation close to open or short-grass area (Folse 1974), which is required for courtship display and foraging. Nest site is frequently located adjacent to dry stream bed or livestock path that serves as conveyance route to and from nest during construction and for young (in Hughes 1996).

In N. California, level areas of open ground and tracts of brush and trees (Kimsey 1953), and valley floors with extensive expanses of grassland and chaparral (W. Bousman pers. comm. in Hughes 1996). In coastal S. California , found in mixed densities of coastal scrub and chaparral, dominated by sagebrush (Artemisia spp.), sage (Salvia spp.), buckwheat, cholla and prickly pear cactus (Opuntia sp.), sumac, yucca, and/or jojoba, adjacent to open or sparsely vegetated areas, including grasslands, roadsides, and weedy sites (P. Famolaro pers. obs.). Occasionally observed in riparian edge and open riparian terrace habitats containing scattered willows, oaks, and mulefat (P. Famolaro pers. obs.)

NEST SUBSTRATE

Often build mock nests prior to nest used for breeding (Whitson 1975). Rarely reuses nests within same breeding season (Woods 1960, Meinzer 1993 in Hughes 1996), however, old nests may be used winter roosting (Rylander 1972 in Hughes 1996). Salvia apiana, Rhamnus crocea, Sambucus mexicana, Malocothamnus fasciculatus, Opuntia parryi, Eucalyptus sp., Pyracantha, Olea (B.A. Carlson field notes 1978-93) may be used for nesting.. Elm (Ulmus spp.), willow (Salix spp.), juniper (Juniperus spp.), and oak (Quercus spp.) may also be used for nesting. Nests in neglected farm machinery (Sutton 1967) and crevices in sandstone cliffs (Dawson 1923) have been recorded (in Hughes 1996.)

HEIGHT OF NEST:

Usually 1-3 meters above ground; infrequently higher than 3 meters (Hughes 1996). One account of nest placed on ground (Bryant 1916 in Hughes 1996).

HEIGHT OF PLANT:

Shrub 253 cm, 220 cm high (B.A. Carlson field notes 1978-93).

NEST CONCEALMENT:

Often well concealed, located near the center of bush (Hughes 1996). Needs more study. Hughes (unpublished data) found that nesting bushes were "less dense on one side and have a greater distance to the lowest branch than that of randomly selected bushes adjacent to the nest site" (in Hughes 1996).

VEGETATION SURROUNDING THE NEST:

DOMINANT PLANT SPECIES IN CANOPY:

Nest host plant typically comprises the highest canopy in the shrub community. See nest substrate for these plants. A study in Brewster Co., w. Texas found the canopy diameter of the nesting bush to be 3.0 m ± 0.6 SD (range 2.3-4.1, n=12) (Hughes unpublished data in Hughes 1996).

AVERAGE COVER:

Needs more information. Studies from San Partricio Co, s. Texas and Brewster Co, w. Texas recorded cover values of 8.5 % ± 0.8 % (range 4-12, n=11) (Folse 1974) and 6.8 % ± 3.0 % (range 2-9, n=12) within a 20 meter radius surrounding nests (Hughes 1996).

GROUND COVER:

Although roadrunners are typically associated with open scrublands intermixed with grass and forb ground cover, no quantified data are available on the herbaceous cover and degree of openness.

SLOPE:

Roadrunners typically occur in flat open scrublands, however, no data are available on degree of slope within a nesting area.

BREEDING BIOLOGY:

With the exception of breeding pairs, roadrunners are solitary (Hughes 1996). Pairs mate for life (Terres 1980).

DISPLAYS:

During courtship, male and female interact and socialize regularly. The pair forages and roosts together and exchanges vocalizations. Males give "Coo" call from an elevated perch. A stick is offered to the mate of either sex, presumably to stimulate nest-building (Whitson 1971). Male "prance display," "tail-wag display," vocalizations, and food or plant material offering occurs just prior to copulation (Whitson 1971 and 1975). Male circles female following 2-3 minute copulation, bows, lowers wings, vocalizes, and performs "flick-bow display." Birds depart in opposite directions after post-copulatory display. Female eats food offering or provides to young if copulation occurs after hatching (Whitson 1975).

NEST TYPE:

Nest is placed in low tree, shrub thicket, or cactus, 1-5 meters high (Baicich and Harrison 1997). Nest is a compact cup or shallow platform built with stiff twigs. Finer material is used as lining, including leaves, grass, feathers, plant seed or pods, snakeskins, roots, and dry flakes of livestock manure (Baicich and Harrison 1997, Hughes 1996 Ehrlich et. al. 1988). The female builds the nest, while the male provides nesting materials.

CLUTCH SIZE:

Usually 3-6 eggs are laid. Up to 13 eggs have been reported, but may be from more than one female (Sutton 1940, Oberholser 1974 in Hughes 1996, Baicich and Harrison 1997)

INCUBATING SEX:

Eggs incubated by both sexes during the day, males at night (Baichich and Harrison 1997).

INCUBATION PERIOD:

19-20 days (Hughes 1996, Baicich and Harrison 1997)

DEVELOPMENT AT HATCHING:

Altricial (Baicich and Harrison 1997)

NESTLING PERIOD:

Young fledge in 11 days and can take flight at 17-19 days. Self feeding begins at 16 days (Baicich and Harrison 1997).

PARENTAL CARE:

Both parents care for young (Hughes 1996)

NUMBER OF BROODS:

Double broods (Hughes 1996)

BROOD PARASITISM:

Roadrunners are potential irregular brood parasites. Roadrunner eggs have been observed in common raven and northern mockingbird nests (Pemberton 1925 and Oberholser 1974 in Hughes 1996). Large clutches of 12 or more eggs may be the result of intraspecies parasitism (Hughes 1996).

LANDSCAPE FACTORS:

ELEVATION:

Roadrunners occur between -60 and 2,300 meters (Small 1994 in Hughes 1996). Grinnell and Miller (1944) identify an exceptional record at 7,500 ft. in the Piute Mountains, Kern County. Based on recent breeding bird atlas and bird census projects, roadrunners have been recorded at the following elevations:

FRAGMENTATION:

Roadrunners regularly utilize open ares (i.e., roads, clearings, grasslands, etc.) adjacent to scrublands, so edges may have value. Fragmentation, in terms of urban and agricultural development, introduces a host of challenges to roadrunners, including but not limited to reduction in available habitat and prey base, vehicle traffic, pets and feral animals, and pesticides.

PATCH SIZE:

No information, however, a minimum patch requirement would encompass 0.7 - 0.8 km diameter (27.9-49.6 hectares), based on the average territory size per pair (Bryant 1916, Calder 1967, and Folse 1974 in Hughes 1996).

DISTURBANCE (natural or managed):

Roadrunners utilize disturbed or open areas for movement and foraging, and can successfully utilize managed disturbed areas (i.e., low density residential dwellings, dirt roads, agricultural fields) (Hughes 1996, P. Famolaro pers. obs.). Intensity of activity within managed or developed areas and urbanization may correlate with reduction in reduction roadrunner populations (Hughes 1996). For instance, irregular use of dirt roads may pose minimal threat to roads runners. When intensity of vehicle activity increases, the chances of roadrunner injuries or mortality also increase.

ADJACENT LAND USE:

Urban encroachment, fragmentation, and intensity of human activity adjacent to remaining occupied habitat pose an increasing threat to roadrunners existence.

SENSITIVITY TO HUMAN-INDUCED DISTURBANCE:

Roadrunner densities were reported as higher in undisturbed habitat than moderately disturbed habitat and suburban residential areas (Tweit and Tweit 1986 in Hughes 1994). Mist nets and snare trapping at nest sites resulted in abandonment of nests (Vehrencamp and Halpenny 1981 in Hughes 1996).

PESTICIDE USE:

Pesticide concentrations, DDT and DDE, have been reported in roadrunners (Hughes 1996).

PREDATORS:

Hawks (Red-tailed and Cooper's) and large mammalian predators (coyotes, raccoons, and striped skunks, as well as snakes (rat snake, coachwhips, and bull snakes) and large corvids (crows and ravens) have been reported (Van Tyne and Sutton 1937, Beal 1978b, and Folse 1974 in Hughes 1996). Pets, feral animals, and racoons are reported as rare causes of mortality among incubating adults (Hughes 1996). Nest predation rates are highly variable with causes unknown (Hughes 1996).

EXOTIC SPECIES INVASION/ENCROACHMENT:

Increasing encroachment into native habitats due to urban and agricultural development has caused local extirpation (McCaskie 1988, Shuford 1992, Lehman 1994, Unitt 1984, Garrett and Dunn 1981 in Hughes 1996). Sparse exotic vegetation and foliage cover may provide inadequate nesting substrate (Hughes 1996).

DEMOGRAPHY AND POPULATION TRENDS:

AGE AND SEX RATIOS:

No information.

PRODUCTIVITY MEASURE(S):

Needs more study. Potential mean annual fecundity of 8.2 eggs/female resulted in 21.5 % fledging success or actual annual fecundity of 1.76 chicks/breeding pair (Folse and Arnold 1978 in Hughes 1996). Nest success may be higher earlier in the breeding season when snakes are less active (M. Maxon pers. comm in Hughes 1996).

SURVIVORSHIP:

Needs more study, but probably long-lived (Hughes 1996). One banded individual was a least 7 years old (K. Klimkiewicz pers. comm in Hughes 1996) and a captive bird lived 9 years (Smith 1979 in Hughes 1979). Between year survival of adults is estimated at 60% (Hughes 1996).

DISPERSAL:

No information available. Site fidelity is expected among breeding adults, although territorial shifts may occur based on site changes, nest failures (Folse 1974 in Hughes), or food availability.

POPULATION TREND: http://www/mbr.nbs.gov/bbs/

MANAGEMENT ISSUES:

ASSOCIATED SPECIES:

California Towhee, Rufous-crowned Sparrow, Black-chinned Sparrow, Sage Sparrow, California Thrasher, California Gnatcatcher, Northern Mockingbird, Western Scrub Jay, California Quail

MONITORING METHODS AND RESEARCH NEEDS:

· Need more information on current abundance, distribution, and population trends. Integrate breeding bird census, atlas projects, and Christmas bird count data.
· More study on individual use areas, dispersal, and survivorship using banded, radio tracked, or marked birds.
· More study on productivity within disturbed as compared to non-disturbed sites
· Study on patch sizes and contiguity to maintain sustainable populations
· Population viability analysis

ACTION PLAN SUMMARY

SPECIES:Greater Roadrunner (Geococcyx californianus)

STATUS: No federal or state status at this time.

No recognized subspecies.

BBS trend data (1966-1999) for California report a negative trend of -3.6% per year. Roadrunners have been locally extirpated from much of coastal southern California (U.S.- Mexico Border to San Francisco Bay Area) and the Central Valley where urban and agricultural development have been extensive.

HABITAT NEEDS:

Roadrunners occupy much of California from the northern Central Valley and coastal areas to the U.S.- Mexico Border and eastward to the Colorado River and north into Owens Valley. Roadrunners occupy open scrublands and/or scrublands bordered by open grassland or disturbed sites, up to 2300 meters. Territory sizes of up to approximately 50 hectares per pair have been recorded, although information on minimum patch size to maintain substainable populations is lacking.

Roadrunners rely heavily on insects for diet, although they often consume a variety of larger prey including lizards, snakes, small mammals, and birds. Fruit and seeds are taken when seasonal available.

CONCERNS:

Continued loss of habitat and urban encroachment are the major threats to roadrunner existence. Pets and feral animals may directly take roadrunners and/or affect nest success. Development of roads through remaining natural areas and increase vehicle activity may increase direct mortality of roadrunners. Roadrunners also continue to be illegally hunted due unjustified claims that they affect quail abundance. Pesticides used in agriculture are transferred to roadrunners through their prey and could have deleterious effects.

BBS trend data show a decreasing trend in roadrunner abundance on the coastal slope of California. Local extirpation has occurred within heavily urbanized and agricultural areas. Although extant populations exists eastward and no-subspecies have been identified, the coastal slope " populations" may warrant federal and state listing or protection.

OBJECTIVES:

· Conserve as much remaining occupied roadrunner habitat as possible.

· Update and improve information on population trends, dynamics, and viability. Investigate patch size requirements and habitat contiguity in the face of continued development within the coastal slope of California.

· Eliminate illegal hunting of roadrunners

ACTIONS:

1. Acquire or protect remaining breeding sites throughout the coastal slope of California. Concentrate conservation where the largest blocks of habitat can be effectively preserved with minimal human disturbance or edge effects (i.e., roads, pets, pesticides, etc.). Participate with federal, state, and local agencies on open space planning and Natural Community Conservation Plans to avoid small patch and fragmented natural open space.

2. Work with scientific community to address information needs to determine sustainable populations. Design and implement necessary studies.

3. Investigate funding sources and develop proposals for habitat acquisition and research needs.

4. Discuss the need for additional protection of roadrunners and their habitats with state and federal wildlife regulatory agencies. If warranted, proposed for threatened or endangered status.

5. Work with enforcement agencies and implement public outreach to eliminate illegal hunting of roadrunners. Education should conducted to refute claims that roadrunners pose a major threat to quail populations.

6. Work with state and local agencies to develop and install road signs for roads which pose a threat to roadrunners.

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