occurs (regularly, as a native taxon) in multiple nations
Regularity: Regularly occurring
Type of Residency: Breeding
Regularity: Regularly occurring
Type of Residency: Year-round
Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) BREEDING: southern British Columbia, southern Alberta, and southern Saskatchewan south to southern California, northwestern Baja California, southern Nevada, Arizona, and through the Mexican highlands to Chiapas and central Guatemala, and east to the central Dakotas, north-central and western Nebraska, central Colorado, eastern New Mexico, and extreme western Texas; disjunctly in southern Baja California (AOU 1983, Greenlaw 1996). See Sauer et al. (2000) for large-scale mapped density estimates (range-wide) based on North American Breeding Bird Survey (BBS) data. NON-BREEDING: south coastal British Columbia, Nevada, Utah, and Colorado (casually farther north) south to Baja California, northern Sonora, through the Mexican breeding range to central Guatemala, and to south-central Texas (AOU 1983).
Length: 22 cm
Weight: 42 grams
Comments: BREEDING: Uses a wide variety of shrubby habitats characterized by deep litter and humus on ground, and sheltering vegetation overhead (Greenlaw 1996). Undergrowth of open woodland, forest edge, second growth, brushy areas, chaparral, riparian thickets, woodland (AOU 1998).
In northern Great Plains, found in shrubby riparian thickets along streams, rivers and coulees, also in woodland undergrowth. In interior mountains and plateaus, uses riparian thickets, open south-facing slopes of ridges, and canyon bottoms. In southern Rocky Mountains, common in pine-oak and pinyon-juniper forests, uncommon in mixed coniferous forests, and rare in ponderosa pine and aspen forests (Hejl et al. 1995). In Colorado pinyon-juniper woodlands, associated with moderately open areas on steep slopes with high shrub cover (Sedgwick 1987). In Pacific Northwest sometimes occurs in shrubby forest successional stages. In California Coast Range, found in chaparral and rose-blackberry thickets (ROSA-RUBRUS; Greenlaw 1996). In Mexico, uses typical brushy woodland and scrub, understory of pine forests and pine-oak woodlands, chaparral, semi-open areas with scattered bushes and brush (Howell and Webb 1995).
Associated with an extensive list of shrubby and thicket-forming plants, including: scrub oaks (QUERCUS spp.), Pinyon Pine (PINUS EDULIS), juniper (JUNIPERUS), yucca (YUCCA spp.), baccharis (BACCHARIS spp.), willow (SALIX spp.), senecio (SENECIO spp.), madrone (ARBUTUS spp.), rose (ROSA spp.), blackberry (RUBUS spp.), saltbush (ATRIPLEX spp.), mountain mahogany (CERCOCARPUS sp.), toyon (HETEROMELES ARBUTIFOLIA), elder (SAMBUCUS spp.), buckthorn (RHAMNUS spp.), sagebrush (ARTEMISIA spp.), snowberry (SYMPHORICARPOS spp.), chamise (ADENOSTOMA spp.), manzanita (ARCTOSTAPHYLOS spp.), sumac (RHUS spp.), Pacific poison-oak (RHUS DIVERSILOBA), ceanothus (CEANOTHUS spp.), and grape (VITIS sp.; Greenlaw 1996). In Mexico, also found in bushy composites (Greenlaw 1996).
Constructs a well-built cup nest in litter on ground, under bush or brush pile, clump of grass, or elevated in vines, trees, bushes, usually between 0.6 and 3.6 m from the ground. Often in relatively exposed conditions, though concealed by nearby plants (Greenlaw 1996; Baicich and Harrison 1997). Elevation of nests may be influenced by rainfall or predation (Greenlaw 1996).
NONBREEDING: Uses similar shrubby habitats and thickets in wintering areas. Nonbreeding birds may occur in areas where towhees do not breed (Greenlaw 1996). In Arizona, winters in Upper Sonoran foothills, in brushy canyons and river valleys of southeastern Arizona, and uncommonly in riparian woodland, willows and marshes along the lower Colorado River (Phillips et al. 1964, Rosenberg et al. 1991).
Habitat and Ecology
Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.
Locally Migrant: Yes. At least some populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.
Migration patterns variable among different populations. Northern interior breeding populations are migratory or partly migratory; increasingly sedentary southward and near coastal areas. Migratory populations arrive in northern breeding areas in March-April (Terres 1980, Greenlaw 1996). Pacific Coastal birds mostly resident, although some in interior coast are short-distance migrants. In some areas summer residents migrate and are replaced by more northern birds that overwinter (Greenlaw 1996).
Spring arrival in northern parts of range between late March and mid-May; fall departure between early September and early October (Greenlaw 1996). Northern Great Plains populations winter in southwest New Mexico to southeast Texas and Mexico. South-central Rocky Mountain populations winter from Arizona to east-central Texas and Mexico. North Central Rocky Mountain birds winter from southern California to southeast Arizona (Greenlaw 1996).
Comments: Forages on the ground beneath shrubs and undergrowth, using a two-footed scratching maneuver to find food among loose debris (Greenlaw 1996). Eats various invertebrates, seeds, small fruits, some small vertebrates (Terres 1980). Diet includes many types of beetles (Coleoptera); grasshoppers and crickets (Orthoptera); true bugs (Heteroptera); ants and wasps (Hymenoptera); flies (Diptera); butterflies and moths, including larvae (Lepidoptera); leafhoppers, aphids and allies (Homoptera); spiders (Araneae); millipedes (Diplopoda); and sowbugs (Isopoda; Greenlaw 1996). Commonly eats seeds and fruits, particularly in nonbreeding season, and sometimes blossoms and young leaves (Dahlsten et al. 1985, Greenlaw 1996). In California, stomach contents (N = 6) were 84.1% animal, 13.2% vegetable and 2.7% mineral (Dahlsten et al. 1985), but relative composition varies with season and locality (Greenlaw 1996). See Greenlaw (1996) for extensive list of plants found in diet. Less known about composition of diet in nonbreeding season, particularly types of invertebrate prey.
Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 to >300
10,000 to >1,000,000 individuals
In nonbreeding season, forms loose flocks and can be somewhat gregarious. Family groups remain together throughout summer (Ehrlich et al. 1988). See Greenlaw (1996) for density estimates and patterns.
Life History and Behavior
Lifespan, longevity, and ageing
Clutch size usually 3-5 (range 2-6). Will renest if first broods suffer mortality, and second broods are uncommon. Incubation, entirely by female, lasts 12-14 days. Only female broods but both parents feed young and remove fecal sacs. Young leave nest unable to fly at 9-11 days; parents continue to feed dependent young out of nest for another 30 days (Ehrlich et al. 1988, Greenlaw 1996, Baicich and Harrison 1997). A host to brood parasites (see Threats above).
Molecular Biology and Genetics
Barcode data: Pipilo maculatus
There are 15 barcode sequences available from BOLD and GenBank. Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species. See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Pipilo maculatus
Public Records: 15
Specimens with Barcodes: 25
Species With Barcodes: 1
National NatureServe Conservation Status
Rounded National Status Rank: N5B - Secure
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Reasons: Widespread distribution from British Columbia south to Central America; most trend estimates stable or increasing. Threatened to some degree by clearing of brushy habitat. Two island subspecies extinct as a result of removal of brush by introduced goats.
IUCN Red List Assessment
Red List Category
Red List Criteria
Global Short Term Trend: Increase of 10 to >25%
Comments: A widespread species that varies greatly in local abundance. BBS trend estimates show long-term stable to increasing populations survey-wide, 1966-1999 (0.6% average annual increase, P = 0.13, N = 618 survey routes) and a significant increase survey-wide between 1980 and 1999 (0.9%, P = 0.02, N = 577). State and province data show significant increases, 1966-1999, in Washington (3.5%, P = 0.00, N = 60), Utah (8.0%, P = 0.04, N = 36), Saskatchewan (5.2%, P = 0.02, N = 15) and British Columbia (1.9%, P = 0.01, N = 47). More recently, significant increases are evident for 1980-1999 in Washington (3.4%, P = 0.00, N = 59), and British Columbia (1.9%, P = 0.03, N = 43). No significant declines evident from the short or long-term trend estimates where sample sizes are large enough for reliable estimates. Mapped trends for 1966-1999 show increasing trends through most of the species' range, with local areas of declining trends along eastern and western range peripheries (Sauer et al. 2000). Two endemic island races, one on Guadalupe Island, Mexico (P. ERYTHROPHTALMUS CONSOBRINUS), and another on San Clemente Island, California are now extinct, both losses due to removal of all shrubby vegetation by domestic goats (Howell and Cade 1953, Jones and Diamond 1976).
Degree of Threat: C : Not very threatened throughout its range, communities often provide natural resources that when exploited alter the composition and structure over the short-term, or communities are self-protecting because they are unsuitable for other uses
Comments: Vulnerable to land management activities that reduce or remove brushy vegetation, particularly along streamsides, in forest understories, and in dry shrubland habitats. PARASITISM: A frequent host to cowbird brood parasitism; host to Brown-headed Cowbird (MOLOTHRUS ATER) in North America and Bronzed Cowbird (M. AENEUS) in Guatemala. Apparently does not cover or reject cowbird eggs (Ehrlich et al. 1988, Greenlaw 1996). Incidence of parasitism has apparently increased as Brown-headed Cowbird has expanded range and increased in abundance (Greenlaw 1996). Also an occasional host to brood parasitism and egg-dumping by California Quail (CALLIPEPLA CALIFORNICA), but no information is available on rate of occurrence (Greenlaw 1996). PREDATION: Predators include Cooper's (A. COOPERI) and Sharp-shinned Hawks (A. STRIATUS; Reynolds and Meslow 1984, Kennedy and Johnson 1986). Other suspected predators of nests and young include King Snake (LAMPROPELTIS GETULUS), Western Scrub-Jay (APHELOCOMA CALIFORNICA), Striped Skunk (MEPHITIS MEPHITIS), Long-tailed Weasel (MUSTELA FRENATA), California Ground Squirrel (SPERMOPHILUS BEECHEYI), and Western Gray Squirrel (SCIURUS GRISEUS, Greenlaw 1996).
Preserve Selection and Design Considerations: Most landscape level relationships for this species are unstudied. Area requirements, use of corridors, and relationships to ecological processes such as fire are unknown. Apparently benefit from forest fragmentation that promotes shrub successional stages, at least for a time (Rosenberg and Raphael 1986, Stiles 1980), but fragmentation and loss of shrub habitats would be detrimental. As towhees often use brushy riparian habitats, they may naturally use stream and river courses as corridors.
The genetic variation evident in this species should be a consideration in conservation. As a group the "red-eyed" towhees (P. ERYTHROPHTHALMUS, P. MACULATUS, and P. OCAI) display complex patterns of geographic variation and hybridization. For P. MACULATUS alone, nine subspecies are recognized in western North America north of Mexico, and another twelve are known in Mexico and Guatemala (Greenlaw 1996). In the Great Plains, Spotted Towhee interbreeds with Eastern Towhee, and in Mexico interbreeds with Collared Towhee (P. OCAI). See Greenlaw (1996) for more detail on patterns of hybridization, subspecies variation, and gene flow. Sibley and Sibley (1964, cited in Greenlaw 1996) suggest that in Mexico, hybridization between species may have been promoted by human alterations of landscapes that modified ecological barriers (such as the altitudinal zonation of vegetation) and created new ecotones where species would overlap.
Management Requirements: Management should focus on maintaining shrub and sapling layers in preferred forest and shrub habitats, particularly extensive areas of dense, woody thickets and riparian willows and brush (Greenlaw 1996). Management activities may be beneficial or detrimental, depending on how shrub habitats are affected. Towhees will coexist with humans where landscapes are lightly to moderately altered and shrub habitats remain, but heavy development, urbanization, and land conversion destroy habitat (Greenlaw 1996). The prevalence of domestic cats in residential and rural landscapes may increase mortality of adult birds and nestlings (Greenlaw 1996). Brood parasitism by Brown-headed Cowbirds (MOLOTHRUS ATER) is a particular concern. Cowbirds are likely affecting productivity in some areas, with possible long-term consequences for local populations.
FOREST MANAGEMENT: Towhees will occupy forest interiors, forest edges, riparian areas and shrub successional stages of harvest units, and natural openings wherever brushy growth provides foraging and nesting habitat. Management activities that remove shrub layers (e.g., timber harvest, grazing, or fire) would be detrimental in the immediate term until shrubs return. On the other hand, timber harvest, prescribed fire, and wildfire that eventually promote shrub growth or increase the area of favored shrub habitats would be beneficial for the time shrub successional habitats remain. Thus management impacts should be analyzed in a context of habitat patterns across landscapes and cumulative effects. Unfortunately, quantitative information on towhee relationships to management activities and ensuing habitat changes is slim.
In Washington, Stiles (1980) found towhees present in early successional stages of Red Alder (ALNUS RUBRA) up to 12 m in height, but absent in older stands with taller alder. In California valley-foothill hardwood, valley-foothill hardwood-conifer, and valley-foothill riparian habitats towhees are associated with shrub understory of sapling age classes with sparse canopy and 10-24% closure (USFS 1994). In California fragmented Douglas-fir (PSEUDOTSUGA MENZIESII) forests, towhees were associated with recent clearcuts and showed significant positive correlations with percent clearcut, total edge, and insularity (degree to which remaining forest stands were surrounded by clearcuts; Rosenberg and Raphael 1986). However, in a Giant Sequoia (SEQUOIA GIGANTEUM) forest, they disappeared from plots where the living and deadwood understory was removed by cutting and prescribed burning (Kilgore 1971). In Colorado pinyon-juniper woodlands, found in natural openings and chained sites where the tree overstory had been removed and shrubs remained. Positively associated with distance to a habitat edge and with shrub height, but negatively associated with tree canopy height and richness of grass and forb species (Sedgwick 1987).
GRAZING: There is little quantitative information available on grazing effects; response would depend on grazing intensity, timing, and subsequent changes to shrubby vegetation. Also of concern, however, is that towhees are frequent cowbird hosts. Cowbirds are attracted by the presence of livestock and cowbird brood parasitism impacts on host bird productivity can be substantial. Thus towhee presence and vegetation structure by themselves are inadequate in determining livestock effects and productivity must be monitored. Cowbird parasitism rates may also be affected and compounded by landscape patterns at different spatial scales (Tewksbury et al. 1999), but this is unstudied in relationship to this species.
Showed a positive response to grazing in aspen (Page et al. 1978, cited in Saab et al. 1995). Sedgwick and Knopf (1987) found that moderate late-fall grazing of cottonwood bottomland plots in northeastern Colorado did not affect densities in the short term (three years). Densities did vary in parallel from year to year in the control and treatment plots.
However, a comparison of grazed and ungrazed pinyon-juniper with oak understory in New Mexico showed that abundance levels are deceptive in determining the effects of grazing. In the first two years of the study, towhees were more abundant in "ungrazed" plots that had been rested from grazing for 20 years than in moderately grazed plots (three-season grazing November-June with 1.3 ha per animal unit month), but no difference was found in abundance in the second two years. However, nest success was lower in grazed plots. Towhees in grazed plots suffered nest failure from weather and brood parasitism by cowbirds (which are attracted by the presence of livestock), whereas birds in the ungrazed plots did not. Twenty-six percent of nests (n = 23) in grazed plots were parasitized. Nest predation rates were the same in the two treatments. Interestingly, the authors found no differences between means of vegetative measures in grazed and ungrazed plots (Goguen and Mathews 1998).
Management Research Needs: Quantitative information is needed on relationships to habitat types, vegetation structure, landscape patterns, and vegetation change over time. Very little information available on the effects of land management activities, and further study is needed of current forest management practices, effects of different grazing regimes in different habitats, and habitat loss to land conversion at local and regional scales. Information needed on rates of brood parasitism and effects on productivity and populations, particularly in relation to landscape patterns. Also need information on rates of predation on eggs and young. Landscape relationships, use of corridors, area and patch size requirements, seasonal movements, and all aspects of ecology during migration and nonbreeding season need further study.
Biological Research Needs: There have been few quantitative studies on the species, the existing studies mostly coming from the Pacific Coast and Mexico, and our knowledge comes largely from anecdotal information (Greenlaw 1996). More information is needed on basic biology and description, genetics, breeding biology, territoriality and territory size, site fidelity, behavior, demography, phenology, migration patterns and pathways, wintering areas, and general ecology. Geographic variation among subspecies and patterns of hybridization need to be studied with genetic methods (Greenlaw 1996).
Relevance to Humans and Ecosystems
Stewardship Overview: A bird of brushy tangles, shrubby streamsides, and forest undergrowth, often in drier shrub habitats than Eastern Towhee. Until recently, considered the same species as Eastern Towhee (P. ERYTHROPHTHALMUS) under the common name Rufous-sided Towhee; both these towhees show a large degree of genetic variation geographically. Can be found in association with human environments where brushy habitats remain, but is vulnerable to brush clearing and to brood parasitism by cowbirds.
Species Impact: None known. May play a beneficial role by feeding on insects and dispersing seeds of soft fruits.
The spotted towhee (Pipilo maculatus) is a large New World sparrow. The taxonomy of the towhees has been debated in recent decades, and formerly this bird and the eastern towhee were considered a single species, the rufous-sided towhee. An archaic name for the spotted towhee is the Oregon towhee (Pipilo maculatus oregonus).
Adults have rufous sides, a white belly and a long dark tail with white edges. The eyes are red. They have white spots on their back and white wing bars. Males have a dark head, upper body and tail; these parts are brown or gray in the female.
The western spotted towhee has white spots on its primary and secondary feathers. The eastern towhee is the same bird in terms of its size and structure but does not have white spots.
They have a round, chunky body, fan shaped tail, short, thick beak, and dull pink legs.
They nest either on the ground or low in bushes, seldom more than 1.5 m (4.9 ft) above the ground. The female builds the nest over a period of about five days. It is bulky and sturdily made of leaves, strips of bark, twigs, forb stalks, and grasses, lined with pine needles, shredded bark, grass, and sometimes hair.
At least two broods, consisting of three to five eggs, are laid per season. The egg shells are grayish or creamy-white, sometimes with a tinge of green, with reddish brown spots that can form a wreath or cap. The female incubates the eggs alone for 12 to 14 days; the young leave the nest at 10 to 12 days. Nests are parasitized by cowbirds.
The call may be harsher and more varied than for the eastern towhee.
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Names and Taxonomy
Comments: Formerly regarded as conspecific with P. ERYTHROPHTHALUMS (AOU 1998). Citing morphological, behavioral, and mtDNA differences (e.g., Ball and Avise 1992), AOU (1995) split the rufous-sided towhee into two species, P. ERYTHROPTHALMUS (eastern towhee, central and eastern North America) and P. MACULATUS (spotted towhee, mainly west of the Great Plains). Limited hybridization occurs in a narrow zone in the central Great Plains. Socorro Island form sometimes regarded as a separate species, P. SOCORROENSIS (Socorro Towhee) (AOU 1998). See Banks and Browning (1995) for a discussion of nomenclatural issues involving PIPILO.