DRAFT
March 2012
BIRDS Gilded Flicker (Colaptes chrysoides)
Gilded Flicker
(Colaptes chrysoides)
Legal Status
State: Endangered
Federal: Bureau of Land Management Sensitive, U.S. Fish and Wildlife Service Bird of Conservation Concern
Critical Habitat: N/A
Recovery Planning: N/A
Notes: Listing status not expected to change during permit period.
Taxonomy
The genus Colaptes contains 12 species of woodpeckers, 2 of which (gilded and northern flickers) are native to North America (Clements et al. 2009). The gilded flicker (C. chrysoides) was formerly treated as a subspecies of the northern flicker C. auratus, but since the 1995 version of the American Ornithologists’ Union (AOU) Checklist (AOU 1995) it has been assigned a species rank based on a variety of data, including DNA studies (Kucera 1997 and citations therein); birds in California have been assigned, along with the Arizona and northern Sonora (Mexico) birds, to subspecies mearnsi (Clements et al. 2009). However, Short (1965) assigns the birds of the lower Colorado River region (including the Desert Renewable Energy Conservation Plan [DRECP] Area) to a hybrid swarm, derived originally from interbreeding of C. auratus and C. chrysoides but now “partially stabilized” and “having little or no genetic contact with populations of the parental forms.” Physical characteristics of the species are detailed by Moore (1995).
Distribution
General
The gilded flicker is native to desert areas surrounding the Gulf of California, including southeast California, extreme southern Nevada, southern Arizona, Sonora, and both northern and southern Baja California (NatureServe 2010; Figure SP-B10). Its range largely coincides with the regional distribution of giant cacti (such as the saguaro [Carnegiea gigantea]), within which it excavates its nest, but it also nests in a variety of other plants (Short 1965; Kucera 1997).
Distribution and Occurrences within the Plan Area
Historical
Grinnell and Miller (1944, pp. 228–230) identify the gilded flicker as occurring in the Lower Colorado River valley from Needles to the Mexican border. They also cite a single instance of a gilded flicker collected in a Joshua tree (Yucca brevifolia) near Cima, about 55 miles northwest of Needles, in 1938. Short (1965, pp. 377–389) also cites numerous records of gilded flickers from the Lower Colorado River, but none from anywhere else in California, referring to lands west of the river as “a barren stretch of uninhabitable terrain.” There are five historical (i.e., pre-1990) California Natural Diversity Database (CNDDB) occurrences in the Plan Area, all of which are located along the Lower Colorado River (Figure SP-B10) (CDFG 2011). Four of the CNDDB occurrences are from 1983.
Recent
There are no recent (i.e., post-1990) CNDDB occurrences for the species in the Plan Area, but it is still assumed to be present in the Lower Colorado River valley, and specifically “at a few sites on the California side of the Colorado River north of Blythe in Riverside County” (CDFG 2004). Surveys performed in 2008 and 2009 throughout the species' range in the Plan Area as a component of riparian bird monitoring for the Lower Colorado River Multi-Species Conservation Program (LCRMSCP) failed to detect the gilded flicker while successfully detecting the five other riparian birds covered under the LCRMSCP (Great Basin Bird Observatory 2009), suggesting that the species may be extirpated or near extirpation in the survey area. However, there are two 2011 observations of gilded flicker contained in the eBird database that are considered valid. These two observations are at a single location just southwest of Parker Dam River along the eastern boundary of the Plan Area (Figure SP-B10) (Dudek 2011).
Natural History
Habitat Requirements
Gilded flickers show a strong primary association with forests of giant cacti, chiefly the saguaro in the United States and a variety of other types in Mexico, at elevations below 3,000 feet. The gilded flicker excavates nests within these cacti, but it may also excavate nests in other suitable vegetation, including species such as cottonwood (Populus spp.) and tree willows (Salix spp.) in riparian woodlands, and sometimes nests in other trees such as mesquite (Prosopis spp.) or Joshua tree (Grinnell and Miller 1944, p. 230; Short 1965, p. 377; Moore 1995; Table 1). Although the distribution of gilded flicker in Arizona is closely associated with large columnar cacti, the gilded flicker is not known from the saguaro areas in California in San Bernardino and Imperial Counties. In California, gilded flickers have been primarily found in the lower Colorado River valley in desert riparian, desert wash, and Joshua tree habitats (Kucera 1997).
Table 1. Habitat Associations for Gilded Flicker in California
Land Cover Type / Land Cover Use / Habitat Designation / Habitat Parameters / Supporting Data /Desert riparian,
Desert wash,
Joshua tree / Nesting, foraging / Primary habitat / Suitable nest trees such as cottonwoods and large willows; insect prey under bark or within wood / AOU 1995; Kucera 1997
Foraging Requirements
Gilded flickers feed on insects, either on the ground or in the air; they also feed on fruits, berries, and seeds (Terres 1980, cited in NatureServe 2010). When gilded and northern flickers were still treated as the same species, Bent (1939) stated that the flicker is “more terrestrial in its feeding habits than any of our other woodpeckers,” and cited evidence that nearly half of their forage consists of ants, with the remainder divided between other animals and plant matter. More detailed studies are not available for the gilded flicker, but all species in the genus Colaptes have a strong affinity for ants, which they lap up with a long, sticky tongue (Short 1965, p. 313; Moore 1995).
Reproduction
Koenig (1984) found that gilded flicker clutch sizes are significantly smaller than those of northern flicker, and suggested that the smaller clutch size must be compensated by other life history traits, including higher survivorship, younger age at first breeding, and a higher rate of double clutching. In the absence of specific information for the gilded flicker, it is worth noting that northern flicker breeds annually and is sexually mature by year one (Moore 1995). The yellow-shafted subspecies of the northern flicker (C. a. auratus) nests by early May and fledges its young by early August (Moore 1995), but these data characterize birds in the eastern U.S. It is likely that these activities occur earlier in the year for California’s gilded flickers. Incubation lasts 11 to 12 days and the nestlings fledge 25 to 28 days later (NatureServe 2010).
Spatial Behavior
Gilded flickers are apparently non-migratory, not even showing local seasonal changes in location (Moore 1995). The species is vigorously territorial during the nesting season, but the demarcation and extent of territory size and spacing has not been studied in the gilded flicker (Moore 1995). Other woodpeckers of similar size have breeding territories of 1 to 10 hectares with home ranges several times larger (NatureServe 2010), but these other species live in upland, spatially continuous, forested habitat that is very different from the linear riparian or Joshua tree woodland habitats used by California's gilded flickers; therefore, information from these other species cannot be readily extrapolated to the gilded flicker.
Ecological Relationships
Short (1965) suggests that gilded flickers are limited in their range by water (the Gulf of California) to the south, by desert lands lacking suitable nest trees to the west, and by competition with the red-shafted subspecies of the northern flicker (C. a. cafer) to the north and east.
Gilded flickers are known to be preyed upon by falcons, accipiters, and buteos, as well as various mammals (Kucera 1997). Flickers commonly excavate their nest sites, and abandoned gilded flicker nests are used by a variety of other cavity nesters, including the elf owl (Micrathene whitneyi) (Kucera 1997; NatureServe 2010).
Population Status and Trends
Global: Stable or slowly declining (Birdlife International 2009)
State: Unknown (CDFG 2004)
Within Plan Area: Insufficient data, but may be extirpated
Threats and Environmental Stressors
Assessments of threats and stressors to the gilded flicker in California have been limited, and the lack of recent observations of the species make it difficult to identify specific threats. The latest assessment, by CDFG (2004), states that the principal stressors to the species are loss and degradation of habitat resulting from land clearing for urban and suburban development and for agriculture, human disturbance, fire in riparian habitat, off-highway vehicles, livestock impacts to tree saplings, invasion of non-native plants, flood control projects, groundwater pumping, and severe flooding due to water releases from dams.
Conservation and Management Activities
The gilded flicker's range in California is within the LCRMSCP area, and it is a covered species under the plan. The LCRMSCP calls for creating and maintaining at least 4,050 acres of cottonwood-willow habitat, increasing representation of this habitat type in the Plan Area (LCRMSCP 2004, Table 5-3), and installing artificial snags to provide nesting habitat. The anticipated outcome should be beneficial to the gilded flicker (LCRMSCP 2004, p. 5-63). No other conservation and management programs for the gilded flicker have been identified in California.
Data Characterization
There has never been a detailed census of the gilded flicker in California. The species has never been abundant in the state and has generally attracted little attention. Consequently, its status and trend in the state are described as unknown, and there have been no recent surveys (CDFG 2004) other than the LCRMSCP surveys reported, which found no gilded flickers despite observing the other riparian covered species. Nonetheless, due to its very limited range and clearly defined habitat requirements, it should be feasible to determine whether a proposed DRECP covered activity has the potential to adversely affect the species or its habitat, and similarly, to identify appropriate mitigation in the form of habitat creation or enhancement, or some other type of management.
Management and Monitoring Considerations
Gilded flicker species-specific survey protocols have not been published. Surveys conducted in 2008 and 2009 used the general riparian bird survey protocol adopted for the LCRMSCP (described by Great Basin Bird Observatory [2009]) and successfully detected the five other covered riparian bird species. Riparian habitat surveys for the species have also been conducted by biologists at the Bill Williams River National Wildlife Refuge. Survey protocols for gilded flicker should be based on these examples, at minimum, and should be performed within habitat areas subject to direct or indirect effects of Covered Activities. Because the gilded flicker is a year-round resident in habitat areas, the principal management strategy should be riparian habitat impact avoidance, especially habitat containing large cottonwoods and tree willows that provide suitable nesting habitat. Pre-impact habitat creation may not be feasible due to the long time period expected to create suitable nesting habitat. However, the results of ongoing monitoring of habitat created for the LCRMSCP by installation of artificial snags should indicate whether habitat creation is successful; if it can be demonstrated that gilded flickers actively use and nest in such habitat, then similar habitat creation efforts may be appropriate for use in the Plan Area.
Predicted Species Distribution in Plan Area
There are 43,927 acres of modeled suitable general habitat for gilded flicker in the Plan Area. Modeled suitable habitat occurs in the southern portion of the Plan Area and along the eastern boundary, below 3,000 feet in elevation. Modeled suitable habitat includes desert scrub, forest and woodland, and riparian vegetation communities. Appendix C includes specific model parameters and a figure showing the modeled suitable habitat in the Plan Area.
Literature Cited
AOU (American Ornithologists Union). 1995. “Fortieth supplement to the American Ornithologists' Union Check-list of North American Birds.” Auk 112:819–830.
Bent, A.C. 1939. Smithsonian Institution United States National Museum Bulletin 174:264–287.
Birdlife International. 2009. “Colaptes chrysoides (Gilded Flicker).” Accessed April 22, 2011. http://www.iucnredlist.org/ apps/redlist/details/141748/0.
CDFG (California Department of Fish and Game). 2004. California Rare & Endangered Birds. Sacramento, California: California Department of Fish and Game.
CDFG. 2011. California Natural Diversity Database (CNDDB). GIS data for the Plan Area. Sacramento, California: California Department of Fish and Game. May 2011.
Dudek. 2011. “Species Occurrences–Colaptes chrysoides.” DRECP Species Occurrence Database. Updated November 2011.
Clements, J.F., T.S. Schulenberg, M.J. Iliff, B.L. Sullivan, and C.L. Wood. 2009. The Clements Checklist of Birds of the World, edited by F. Gill and D. Donsker. Version 6.5.
Great Basin Bird Observatory. 2009. Annual Report on the Lower Colorado River Riparian Bird Surveys, 2009. System Monitoring for Riparian Obligate Avian Species (Work Task D6) and Avian Use of Restoration Sites (Work Task F2) - Lower Colorado River Multi-Species Conservation Program No. 07SF300004. Submitted to Bureau of Reclamation, Lower Colorado River Region. December 31, 2009. Accessed June 9, 2011. http://www.lcrmscp.gov/worktasks/systemmonitoring/D6/LCRRiparianBirds09.pdf.
Grinnell, J., and A.H. Miller. 1944. The Distribution of the Birds of California. Pacific Coast Avifauna no. 27. Berkeley, California: Cooper Ornithological Club.
Koenig, W.D. 1984. “Clutch Size of the Gilded Flicker.” Condor 86:89–90.
Kucera, T. 1997. “Life History Account for the Gilded Flicker.” Last revised 1997. Accessed April 20, 2011. https://nrmsecure.dfg.ca.gov/FileHandler.ashx?DocumentVersionID=17727.
LCRMSCP (Lower Colorado River Multi-Species Conservation Program). 2004. Lower Colorado River Multi-Species Conservation Program. Vol. 2, Habitat Conservation Plan. Final. December 17, 2004. J&S 00450.00. Sacramento, California.
Moore, W.S. 1995. “Gilded flicker (Colaptes chrysoides).” The Birds of North America Online, edited by A. Poole. Ithaca, New York: Cornell Lab of Ornithology. Accessed April 20, 2011. http://bna.birds.cornell.edu/bna/species/166b.
NatureServe. 2010. “Comprehensive Report Species – Colaptes chrysoides.” NatureServe Explorer: An Online Encyclopedia of Life [web application]. Version 7.1. Arlington, Virginia: NatureServe. Last revised August 2010. Accessed April 20, 2011. http://www.natureserve.org/explorer/servlet/ NatureServe?searchName=colaptes+chrysoides.
Short , L.L., Jr. 1965. “Hybridization in the Flickers (Colaptes) of North America.” Bulletin of the American Museum of Natural History 129(4):307–428.
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