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The eastern towhee (Pipilo erythrophthalmus), also known as chewink, joree, or joree bird,<ref>https://www.carolinabirdclub.org/BOCC/Passerines/20%20Towhees,%20Sparrows,%20Juncos/Eastern%20Towhee.pdf</ref> is a large New World sparrow. The taxonomy of the towhees has been under debate in recent decades, and formerly this bird and the spotted towhee were considered a single species, the rufous-sided towhee.

Their breeding habitat is brushy areas across eastern North America. They nest either low in bushes or on the ground under shrubs. Northern birds migrate to the southern United States. There has been one record of this species as a vagrant to western Europe: a single bird in Great Britain in 1966.<ref>Template:Cite book</ref>

The song is a short drink your teeeeea lasting around one second, starting with a sharp call ("drink!") and ending with a short trill "teeeeea". The name "towhee" is onomatopoeic description of one of the towhee's most common calls, a short two-part call rising in pitch and sometimes also called a "chewink" call.<ref name=r42/>

TaxonomyEdit

The eastern towhee was described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae and given the binomial name Fringilla erythrophthalma.<ref>Template:Cite book</ref> This species is now placed in the genus Pipilo that was introduced by the French ornithologist Louis Pierre Vieillot in 1816.<ref>Template:Cite book</ref> The specific name erythrophthalmus/erythrophthalma combines the Ancient Greek words ερυθρος eruthros "red" and οφθαλμος ophthalmos "eye".<ref name=hbwkey>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Four subspecies are recognised:<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

  • P. e. erythrophalmus (Linnaeus, 1758), found south-central and southeast Canada to the eastern United States
  • P. e. canaster (Howell, AH, 1913), found in the interior southeast United States
  • P. e. rileyi (Koelz, 1939), found in the coastal southeast United States except for central and southern Florida
  • P. e. alleni (Coues, 1871) found in south and central Florida

DescriptionEdit

The eastern towhee is a large and striking species of sparrow. The total length ranges from Template:Convert and the wingspan is Template:Convert.<ref>Eastern Towhee, Life History, All About Birds – Cornell Lab of Ornithology. Allaboutbirds.org. Retrieved on 2013-01-05.</ref><ref>Eastern Towhee Pipilo erythrophthalmus Template:Webarchive. Georgia Museum of Natural History (2008). Retrieved on 2013-01-05.</ref> The body of mass of this species ranges from Template:Convert, with an average of Template:Convert.<ref>CRC Handbook of Avian Body Masses by John B. Dunning Jr. (Editor). CRC Press (1992), Template:ISBN.</ref> Adults have rufous sides, a white belly, and a long dark tail with white edges. The eyes are red for most populations, though populations in the southeastern U.S. have yellow eyes – often referred to as the "white-eye morph."<ref>Template:Cite journal</ref> Males have a black head, upper body, and tail; these parts are brown in the female. Juveniles are brown overall. Eastern towhees of all ages and both sexes generally are unmistakable. In the Great Plains, eastern towhees will occasionally overlap in range with their sister species, the spotted towhee, which has resulted in rare hybrids between the two species.<ref>Template:Cite journal</ref>

DistributionEdit

The eastern towhee occurs throughout the eastern United States and southeast Canada. Occurrences from southern Saskatchewan, southwest Ontario and Quebec south to Florida, and west to eastern Texas are noted in a literature review. Populations north of southern New England through northern Indiana and Illinois to southern Iowa primarily are summer residents.<ref name=r42/>

Pipilo e. erythrophthalmus occurs in the most northerly part of the eastern towhee's distribution in the summer, and in winter migrates to the southern and eastern portion of the range of the species. The other subspecies are largely residents.<ref name=r69/> Pipilo e. canaster occurs from south-central Louisiana, north to northeastern Louisiana east through Mississippi, extreme southwestern Tennessee, northern Alabama and Georgia, central South Carolina to western North Carolina, and south to northwestern Florida and east along the Gulf Coast.<ref>American Ornithologists' Union. (1957). Checklist of North American birds. 5th ed. Baltimore, MD: The Lord Baltimore Press, Inc.</ref> The range of P. e. rileyi extends from northern Florida through southern Georgia and coastal South Carolina to east-central North Carolina. Pipilo e. alleni occurs in peninsular Florida.<ref name=r69/>

The eastern towhee occurs in vegetation of disturbed areas, such as old-field successional vegetation and shrubby areas of power line right-of-ways. In northwestern Arkansas, eastern towhees occurred in old-field vegetation where dwarf sumac (Rhus copallina) occurred at a frequency of 28.6%, winged elm (Ulmus alata) at a frequency of 21%, and black cherry (Prunus serotina) at a frequency of 19.2%.<ref name=r7/> Shrubby vegetation along power lines is commonly used by eastern towhees.<ref name=r37>Gates, J. Edward; Dixon, Kenneth R. (1981). "Right-of-way utilization by forest- and corridor-breeding bird populations". In: Arner, Dale, ed. Environmental concerns in right-of-way management: Proceeding of 2nd symposium; 1979 October 16–18; Ann Arbor, MI. Special Study Project WS-78-141: 66–1 to 66–7</ref> For example, in Maryland, eastern towhee territories along a power line right-of-way corresponded with shrubby areas containing species such as Allegheny blackberry (Rubus allegheniensis) and blueberry (Vaccinium spp.). Other species included hawthorn (Crataegus spp.), red maple (Acer rubrum), black cherry, and black locust (Robinia pseudoacacia).<ref name=r37/>

From 1966 to 2015, the eastern towhee experienced a greater than 1.5% annual population decrease throughout the Atlantic seaboard and the northern part of its breeding range.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Timing of major life eventsEdit

Arrival and departure of eastern towhees into summer breeding grounds varies with location. According to a literature review, eastern towhees typically arrive in New York in early April and leave by the middle of November. A review of eastern towhees in New Hampshire describes arrival in late April to May with the majority departing in September.<ref name=r34/> Further south, on the border of Tennessee and North Carolina, migration to high-elevation areas within the Great Smoky Mountains begins as early as March. Eastern towhees typically leave these sites in October.<ref name=r88/> The Pipilo e. erythrophthalmus subspecies is the most migratory of the subspecies.<ref name=r69>National Geographic Society. (1999). Field guide to the birds of North America. 3rd ed. Washington, DC: The National Geographic Society Template:ISBN.</ref>

Breeding begins in spring and continues to late summer. Reports of eastern towhees nesting as early as late March in Florida and Georgia, in mid- to late April in some midwestern states, and as late as mid-May in northern New England were summarized in a literature review.<ref name=r42/> Literature reviews also report nest construction by the female, which takes about three to five days.<ref name=r42/><ref name=r34/> Egg laying typically occurs until August. For example, a review of eastern towhees in Indiana notes nesting from 15 April to 20 August.<ref name=r67/> However, a literature review of eastern towhees in Florida included a report of a nest observed on 2 September 1983 that contained two eggs.<ref name=r86/> According to several literature reviews, eastern towhees may renest after failed nesting attempts and can raise two, and in the south sometimes three, broods per season.<ref name=r42/><ref name=r34/><ref name=r86/>

In a literature review, Greenlaw <ref name="r42" /> reports mean breeding territory size of Template:Convert (range Template:Convert, n=24) in a mesic oak (Quercus species) forest where eastern towhees occurred at a density of 21 males/40 ha. In a xeric pine (Pinus species)-oak woodland where the eastern towhee density was 32 males/40 ha, mean eastern towhee territory size was Template:Convert (range Template:Convert, n=20).<ref name="r42" /> In Massachusetts, mean male eastern towhee territory size was about Template:Convert, and female eastern towhee territory size was Template:Convert. Territory size changed over the course of the breeding season and was not significantly (p>0.05) affected by reductions in food availability of 30% or less. During the winter eastern towhees are not as territorial and may be seen in mixed species flocks.<ref name="r42" /> Daily movement of eastern towhees in loblolly (P. taeda) and longleaf pine (P. palustris) forests and clearcuts in South Carolina averaged Template:Convert per day. Only 2 females, out of 11 females and 9 males, stayed within the stand where they were captured for the duration of a 10-week study.<ref name="r52" />

Eastern towhees have fairly strong fidelity to breeding territories. In an oak forest in New Jersey, adult eastern towhee return rates were 20% the 1st year after banding and 43% in subsequent years. Between 1960 and 1967, the maximum number of eastern towhee returns to the site was 5.<ref name=j3/> In a Pennsylvania woodlot observed between 1962 and 1967, an eastern towhee returned to the site for 4 consecutive years.<ref name=r79/>

Several reviews report eastern towhee clutch sizes from 2 to 6 eggs, with means ranging from 2.45 to 3.6 eggs per nest.<ref name=r42/><ref name=r34/><ref name=r67/><ref name=r86/> All 5 eastern towhee nests on Sanibel Island, Florida, contained 3 eggs.<ref name=r74/> Eastern towhees in 2 pitch pine (P. rigida) barrens sites in New Jersey and New York had a later median egg laying date (mid-June) and significantly (p<0.05) smaller average early nest clutch sizes (NJ=2.67, NY=3.25) than those in an oak-hickory (Carya spp.) site, which had a median egg-laying date in early June and an average early nest clutch size of 3.88. Food availability likely explains at least some of the differences between the 2 habitat types. Eggs are incubated by the female for 12 or 13 days. After hatching both parents feed the young, which fledge 10 to 12 days later and are dependent on parental care for about another month.<ref name=r42/><ref name=r34>Foss, Carol R. (1994). Atlas of breeding birds in New Hampshire. Dover, NH: Audubon Society of New Hampshire Template:ISBN.</ref><ref name=r67/><ref name=r86/>

A wide range of eastern towhee nest success values have been reported. On Sanibel Island, 1 of the 5 eastern towhee nests observed was successful. In Louisiana, average daily nest success rate was 95.3% on a bottomland hardwood forest site. The same study found a 92.6% average daily nest success rate in a 6-year-old managed cottonwood (Populus spp.) plantation in Alabama. Average eastern towhee nest success across mixed bigtooth (P. grandidentata) and quaking aspen (P. tremuloides) stands of varying ages in Pennsylvania was 48.1%.<ref name=r103/> In South Carolina, only 1 of 10 nests was successful, and the mean daily nest survival rate was 62.9%. This low value was explained by high levels of predation. Due to lower nest success rates of Bachman's sparrow (Aimophila aestivalis) than the previous year, it is suggested that eastern towhee nest success may have been measured during a comparatively poor year.<ref name=r52/>

Compared to nests, adult towhee survival rates are high. Average weekly adult survival rate of eastern towhees in a South Carolina study area was 99.3%. This rate was obtained from radio-marked eastern towhees and represented the pooled survival of both sexes and from 2 South Carolina sites, young and mature stands of loblolly and longleaf pine.<ref name=r52/> Between 1962 and 1967 in Pennsylvania, annual survival of breeding eastern towhees calculated from mistnetting recaptures was 58%.<ref name=r79/> According to a literature review, both males and females become reproductively mature in their second year.<ref name=r42/> Eastern towhees of over 12 years old have been reported in the wild.<ref name=r51/>

Preferred habitatEdit

Eastern towhees range from near sea level to as high as Template:Convert along the border of Tennessee and North Carolina during the summer.<ref name=r88>Stupka, Arthur. (1963). Notes on the birds of Great Smoky Mountains National Park. Knoxville, TN: The University of Tennessee Press</ref> A literature review reports eastern towhees up to Template:Convert in New Hampshire.<ref name=r34/>

Eastern towhees spend the majority of their time near the ground. For instance, in Pennsylvania in spring, observations of eastern towhees below Template:Convert from the ground occurred significantly (p<0.05) more than expected based on random spatial distribution, and observations above Template:Convert occurred significantly (p<0.05) less than would be expected.<ref name=r102/> In a Louisiana bottomland forest 62% of eastern towhee observations were within Template:Convert of the ground, and only 4% were observed above Template:Convert. In the spring this changed, with detections of eastern towhees below Template:Convert declining from 70% to 65% and detections in the canopy (>Template:Convert) increasing from 4% to 7%.<ref name=j1/>

Eastern towhees occur in many habitats, from tallgrass prairies and marshes to mature forests.<ref name=r52/> However, eastern towhees are most common in early successional stands, habitat edges, and areas with similar vegetation structure throughout eastern forests.

In most communities eastern towhees are more abundant in young successional stands. Several studies found increased eastern towhee abundance on early successional sites compared to later-successional sites.<ref name=r102/><ref name=r28/><ref name=r49/><ref name=r56/> Mean number of breeding eastern towhees (0.70 bird/50-m radius) and nest success rate (58%) were higher in a 15-year-old clearcut in West Virginia, than in other treatments, including a stand of yellow-poplar (Liriodendron tulipifera), black cherry, red maple, sugar maple (Acer saccharum), and white ash (Fraxinus americana) that was not harvested.<ref name=r28/> In a southern Missouri oak-hickory forest, eastern towhees were not present before clearcutting or in the nearby uncut forest after cutting, but occurred at a mean density of 9.3 birds/10 ha in a 3-year-old clearcut. A study of stands of varying ages in central New York found that eastern towhee density peaked in early successional stands.<ref name=r49/>

Although eastern towhees generally prefer young successional sites, variation between habitat types and years has been observed. Krementz and Powell <ref name=r52/> found higher relative abundance of eastern towhee in young (2–6 years old) stands of loblolly and longleaf pine than mature (32–98 years old) stands when investigated in 1995. However, in stands compared in 1996, the 95% confidence intervals of eastern towhee relative abundance on the 2 sites had a substantial degree of overlap. The degree to which eastern towhee responds to succession is influenced by habitat. For example, in Pennsylvania there was a significant (p<0.05) difference between eastern towhee densities (number/10 ha) between mature mixed-oak forest and stands that had been clearcut about 5 years previously. However, eastern towhee densities did not differ significantly between a 1-year-old mixed aspen (Populus tremuloides, P. grandidentata) clearcut, a 5-year-old aspen clearcut, and a mature aspen stand.<ref name=r101/> Eastern towhee abundance has been shown to peak at different times in different habitats. For instance, although in central hardwood forests eastern towhees were most abundant in regenerating stands, in loblolly and shortleaf pine forest they were most common in pole timber and mature stands. In addition, Bell and Whitmore concluded that early successional is likely too broad a term for describing optimal towhee habitat, since high density of small trees was negatively associated with eastern towhee density in the eastern panhandle of West Virginia.<ref name=r8/>

Eastern towhees seem to prefer sites with characteristics generally associated with early successional vegetation, such as low canopy cover and dense understory. Negative correlations between eastern towhee abundance and various measurements of overstory density have been found in several studies.<ref name=r7>Bay, Michael Daymon. (1994). Effects of area and vegetation on breeding bird communities in early successional oldfields. Fayetteville, AR: University of Arkansas. Dissertation.</ref><ref name=r101/> Average density of eastern towhees across 6 habitat types in Pennsylvania was significantly (p<0.05) negatively correlated with density of overstory trees and basal area of overstory trees.<ref name=r101/> Number of eastern towhees in a western Virginia hardwood forest was also significantly (p<0.05) inversely correlated with total percent canopy cover. In a loblolly pine forest in South Carolina, the average number of eastern towhee breeding territories per experimental unit was significantly (p≤0.008) negatively correlated with mid-story (Template:Convert) pine (Pinus spp.) and deciduous volume.<ref name=r59/>

Many studies have demonstrated a positive correlation between eastern towhee abundance and understory density. In a loblolly pine forest in South Carolina, understory (Template:Convert) pine volume was significantly (p<0.001) positively correlated with the average number of eastern towhee territories per experimental unit.<ref name=r59/> Yahner <ref name=r101/> found the average density of eastern towhees over 6 habitat types was significantly (p<0.05) positively correlated with density of short (2–5-foot (0.5–1.5 m)) shrubs. In east-central Florida slash pine (P. elliottii) flatwoods with understories dominated by myrtle oak (Q. myrtifolia) and sand live oak (Q. geminata) and in scrub sites with scattered slash pine and cabbage palmetto (Sabal palmetto), eastern towhee densities were significantly (p=0.01) negatively correlated with mean shrub height.<ref name=r14/>

Eastern towhees may associate with and avoid certain plants. In Nevada, Towhees seem to prefer a habitat in which they are camouflaged such as flowering quince which matches their rufous coloration. In riparian vegetation in Iowa, eastern towhee density was significantly (p≤0.01) positively associated with total plant and vine species richness and negatively correlated with forb and deciduous tree species richness.<ref name=r85/> In West Virginia, eastern towhees were associated with plant species that occurred on drier ridgetops, such as blackberry (p<0.02), black cherry (p<0.002), and black locust (p<0.04). These sites tended to have open canopies and low tree density. Eastern towhee density was negatively associated with plants of the moister parts of this study area, such as black tupelo (Nyssa sylvatica, p<0.006), red maple (p<0.001), and witch hazel (p<0.03).<ref name=r8/> In central New Jersey eastern towhees were significantly (p=0.03) more abundant in gray dogwood (Cornus racemosa) shrubland than either eastern redcedar (Juniperus virginiana) or multiflora rose (Rosa multiflora) shrublands.<ref name=r89/>

File:Eastern Towhee Durham NC.jpg
Nest with hatchlings in North Carolina

Nesting habitat: Eastern towhees typically nest on or near the ground. Several literature reviews note the predominance of eastern towhee nests below Template:Convert.<ref name=r42/><ref name=r34/><ref name=r67>Mumford, Russell E.; Keller, Charles E. (1984). The birds of Indiana. Bloomington, IN: Indiana University Press Template:ISBN.</ref><ref name=r86/> In a study of cowbird parasitism on Sanibel Island, all 5 eastern towhee nests located were within Template:Convert of the ground.<ref name=r74/> Nests as high as Template:Convert have been reported in literature reviews.<ref name=r42>Greenlaw, Jon S. (1996). Easter towhee – Pipilo erythrophthalmus. In: Poole, A.; Gill, F., eds. The birds of North America. No. 262: 1–32</ref><ref name=r34/><ref name=r67/> Nests higher off the ground in mixed aspen stands of varying ages in Pennsylvania had significantly (p<0.001) lower nest success. Of 13 unsuccessful eastern towhee nests, 11 were greater than Template:Convert above the ground.<ref name=r103/>

In West Virginia, there were no significant (p>0.05) differences in habitat surrounding successful and unsuccessful nests. Large snags (≥9 inches diameter at breast height (≥22.9 cm)) did not have an effect on nesting success.<ref name=r9/> Nesting success was not significantly (p>0.05) affected by stand age or distance to edge in even-aged mixed-aspen stands in Pennsylvania.<ref name=r103/>

Eastern towhees nest in a variety of species including grape and blueberry (Vaccinium spp.). The majority of nests observed in South Carolina loblolly and longleaf pine forests and clearcuts were located in grape, tree sparkleberry (V. arboreum), and oak (Quercus spp.).<ref name=r52/> On an oak-hickory site in West Virginia, 27% of 41 eastern towhee nests were found in grape, 17% in blackberry (Rubus spp.), 12% in greenbrier (Smilax spp.), and 12% in mountain-laurel (Kalmia latifolia). Nests also occurred in Virginia creeper (Parthenocissus quinquefolia), spice bush (Lindera benzoin), and azalea (Rhododendron spp.).<ref name=r9/> In a power line right-of-way in Pennsylvania, the 6 eastern towhee nests observed occurred in Allegheny blackberry, witch-hazel (Hamamelis virginiana), blueberry (Vaccinium spp.), white oak (Q. alba), eastern hayscented fern (Dennstaedtia punctilobula) and sweetfern (Comptonia peregrina) combined, and on ground level. According to literature reviews, eastern towhee nests located on the ground are embedded in litter in dry areas and typically occur at the base of grasses, forbs, low shrubs, or small trees.<ref name=r42/><ref name=r67/>

Foraging habitat: Selection of foraging habitat by eastern towhees has been investigated in Massachusetts and New Jersey. When gleaning in a southeastern Massachusetts pitch pine barren, eastern towhees preferred species such as pitch pine, bear oak (Q. ilicifolia), and other deciduous trees, mainly oaks. Ericaceous species were avoided. Use differed significantly (p<0.001) from availability.<ref name=r66/> On 2 New Jersey sites, eastern towhee foraging preference switched over the course of the breeding season.<ref name=r15/> On a site dominated by oaks, primarily black oak (Q. velutina), eastern towhees used oaks in May, as would be expected due to their density. However, in June and July, as relative arthropod biomass declined in oaks, use of oaks was less than would be expected. On a pitch pine-dominated site, use of oaks (primarily bear oak and blackjack oak, Q. marilandica) was greater than would be expected in May, but was proportionate to availability in June and July. These negative correlations between date and oak use were significant (p<0.025) for both sites. Use of the oak-dominated site also decreased significantly (p<0.05) through the summer.<ref name=r15/>

Effects of spatial area: Eastern towhees appear to prefer edge habitats in many areas. For instance, the mean abundance of eastern towhees in a baldcypress (Taxodium distichum) in northern Florida was 18, while eastern towhees did not occur in either the baldcypress forest or the clearcut. At the interface of the baldcypress stand and a 13-year-old planted slash pine stand, mean abundance of eastern towhees was 22 breeding birds, while in the planted slash pine stand the average abundance was 15 breeding birds. Density of eastern towhees was found to decline with distance from the edge of a power line right-of-way and an oak-hickory forest in eastern Tennessee. At the edge, eastern towhees occurred at a density of just over 10 pairs/40 ha, while Template:Convert from the edge eastern towhee density had dropped to 1 pair/40 ha.<ref name=j2/> In addition, in experimentally clearcut Pennsylvanian forests composed of white oak, northern red oak (Q. rubra), chestnut oak (Q. prinus), scarlet oak (Q. coccinea), red maple, quaking aspen, bigtooth aspen, and pitch pine, male towhees were detected significantly (p<0.05) more often than expected in the areas where the spatial arrangement of clearcuts was most patchy.<ref name=r58/>

Several studies have addressed the effect of the size of habitat patches on eastern towhees. In mixed-oak forest in New Jersey, eastern towhee frequency generally increased with patch size, although eastern towhees were detected in all plot sizes (Template:Convert) except 0.02–acre (0.01 ha) plots. On a site in South Carolina, eastern towhee frequency of occurrence increased as clearcut size increased from <Template:Convert to clearcut sizes from 21 to about 32 acres (8.5–12.8 ha). On another site eastern towhee frequency declined as clearcut size increased from Template:Convert.<ref name=r56/> Eastern towhees bred in only those riparian vegetation patches in Iowa that were at least Template:Convert wide.<ref name=r85/> In southern and eastern Pennsylvania eastern towhee nest success was not significantly (p≥0.10) different on sites with gradual edges and those with more distinct edges between "wildlife habitat openings" and oak-hickory forest.<ref name=r26/>

Food habitsEdit

Eastern towhees primarily eat on the ground, although they also glean from vegetation. In a southeastern Massachusetts pitch pine barren, 73.5% of male and 80.4% of female foraging observations were on the ground.<ref name=r66/> When foraging on the ground eastern towhees use a scratching technique where both feet kick back simultaneously.<ref name=r86>Stevenson, Henry M.; Anderson, Bruce H. 1994. The birdlife of Florida. Gainesville, FL: University of Florida Press</ref> In a laboratory study 4 eastern towhees used this method to successfully obtain seed buried almost Template:Convert deep. When foraging above ground the majority of time is spent gleaning foliage.<ref name=r66/> In Massachusetts, 22.5% of male and 16.3% of female foraging observations were of food being gleaned from foliage. Eastern towhees were also observed gleaning from twigs, branches, and trunks. When gleaning, eastern towhees occurred significantly (p<0.01) more often on the distal half of tree branches compared to using distal and proximal portions equally. In 0.5% of male and 0.3% of female foraging observations, eastern towhees hovered. Eastern towhees were never observed catching food out of the air.<ref name=r66/>

Eastern towhees eat a variety of plant and animal matter. In literature reviews, eastern towhees are reported to eat seeds and fruits, several invertebrates, and occasionally small amphibians, snakes, and lizards.<ref name=r86/> Reviews report eastern towhees foraging at feeders.<ref name=r42/> Reviews show that animal matter makes up a larger proportion of the diet in the breeding season.<ref name=r42/><ref name=r63/> In fall and winter, plants make up 79% and 85% of the diet, respectively. This drops to 53% in spring and 43% in summer.<ref name=r63/> Insects such as beetles (Coleoptera), grasshoppers and crickets (Orthoptera), ants, wasps, and bees (Hymenoptera), and moths and caterpillars (Lepidoptera) are common prey items. Eastern towhees eat other invertebrates such as spiders (Araneae), millipedes (Diplopoda), centipedes (Chilopoda), and snails (Gastropoda) to a lesser extent.<ref name=r42/><ref name=r63>Martin, Alexander C.; Zim, Herbert S.; Nelson, Arnold L. (1951). American wildlife and plants. New York: McGraw-Hill Bood Company, Inc.</ref> Plants that comprise at least 5% of the eastern towhee diet include ragweed (Ambrosia spp.), oak, smartweed (Polygonum spp.), and corn (Zea mays) in the Northeast and blackberry, oak, panicgrass (Panicum spp.), ragweed, and wax-myrtle (Morella cerifera) in the Southeast.<ref name=r63/>

PredatorsEdit

Many animals prey on eastern towhees and their eggs, including reptiles, mammals, and birds. A literature review summarizes several reports demonstrating that predators are a major cause of nest failure.<ref name=r42/> The highest nest predation rate noted was 88% in a New York study. Mammals that are likely nest predators include northern raccoons (Procyon lotor), domestic cats (Felis catus), and eastern chipmunks (Tamias striatus). Snakes such as bullsnakes (Pituophis catenifer), rat snakes (Elaphe spp.) and garter snakes (Thamnophis spp.) have been reported eating eastern towhee eggs. Weasels (Mustela spp.) and blue jays (Cyanocitta cristata) are also likely nest predators.<ref name=r42/> Several birds are known to prey on both young and adult eastern towhees, including northern goshawk (Accipiter gentilis), Broad-winged (Buteo platypterus), short-tailed (Buteo brachyurus), sharp-shinned (Accipiter striatus) and Cooper's hawks (Accipiter cooperii). Other predators include barred (Strix varia), short-eared (Asio flammeus) and eastern screech-owls (Megascops asio) and even the loggerhead shrike (Lanius ludovicianus), which is scarcely larger than a towhee.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> At least some mammals also feed on adult eastern towhees. In Maryland, an eastern towhee was found in the stomach contents of a red fox (Vulpes vulpes).<ref name=r47/>

Brown-headed cowbirds (Molothrus ater) parasitize eastern towhee nests. In a South Carolina old field, 5 of 19 eastern towhee nests were parasitized.<ref name=r100/> Each parasitized nest contained 1 Brown-headed Cowbird egg. The desertion rate for parasitized nests was 20%, which was similar to nests that had not been parasitized (21%). Two of the five Brown-headed Cowbird eggs produced fledglings. The study did not determine if there was a difference in nest success between parasitized and nonparasitized nests.<ref name=r100/> In West Virginia, only 3 of 41 eastern towhee nests were parasitized by the Brown-headed Cowbird. Average number of fledged young in nonparasitized nests was 2.8, which was similar to the average of 2.7 fledglings per parasitized nest.<ref name=r9/> In a Pennsylvania study site, only 2 of 36 nests were parasitized and both produced eastern towhee fledglings.<ref name=r26>Diefenbach, Duane R. (1996). Abundance and nest success of songbirds in simple and complex edge habitats. Final Report Project 06510. Harrisburg, PA: Pennsylvania Game Commission</ref> In a study of nest parasitism on Sanibel Island, none of 5 eastern towhee nests found were parasitized.<ref name=r74/>

ReferencesEdit

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External linksEdit

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