Northern Prairie Wildlife Research Center
Migrants return to Ohio beginning in February and March. Nesting activities begin by mid-April. Recently fledged young have been reported as early as 16 May, but most first broods do not fledge until 10-25 June. Fall migration begins the first week of September and peaks between 15 September and 25 October. Wintering eastern meadowlarks are rare in northern counties and most numerous in southern counties (Peterjohn 1989, Peterjohn and Rice 1991)
Preferred nesting habitats of the eastern meadowlark in Ohio include lightly-grazed pastures, hayfields, idle fields, and grassy rights-of-way along highways, railroads, and airport runways (Peterjohn 1989). Today, the largest populations occupy reclaimed surface mines in eastern counties (Peterjohn and Rice 1991).
Sample (1989) considered the eastern meadowlark a habitat generalist as it was absent only from those habitats with little vegetative cover (e.g., rowcrops). Several other studies also reported that eastern meadowlarks occupied a wide variety of habitats (Lanyon 1957, Speirs and Orenstein 1965, Roseberry and Klimstra 1970). Most researchers considered pastures and hayfields the preferred nesting habitats of eastern meadowlarks (Good and Dambach 1943; Lanyon 1953, 1956a,b, 1957; Bent 1958; Speirs and Orenstein 1965; Wiens 1969; Roseberry and Klimstra 1970; Shugart and James 1973; Harrison 1977; George et al. 1979; Sample 1989). Other habitats used by eastern meadowlarks for nesting include old fields (Knapton 1988, Sample 1989), CRP grasslands (Hays et al.1989, Lauber 1991, Welsh and Kimmel 1991, Swanson et al. 1995), meadows (Dambach and Good 1940), native and restored tallgrass prairie (Lanyon 1956a, Herkert 1991, Volkert 1992), reclaimed surface mines (Whitmore and Hall 1978, Whitmore 1979b), roadside and railroad rights-of-way (Braband 1984, Warner 1992), woodland clearings (Lanyon 1953), golf course fairways (Roseberry and Klimstra 1970), small grains (Dambach and Good 1940, Bent 1958, Roseberry and Klimstra 1970), cultivated rowcrops (Bent 1958, Castrale 1985), and no-tillage corn and soybeans (Castrale 1985).
Lanyon (1956a,b, 1957) regarded the eastern meadowlark a bird of moist, lowland areas supporting tall vegetation, whereas Sample (1989) found eastern meadowlarks most abundant in dry habitats with short to intermediate height vegetation. Sample (1989) observed the highest densities of eastern meadowlarks in dry, uncut grasslands, lower densities in lush, mesic habitats, and none in rowcrops. In Ohio, Good and Dambach (1943) reported densities of 7.8 nests/40 ha in meadows and 0.3 nests/40 ha in corn and small grains. Roseberry and Klimstra (1970) reported highest nesting densities in pastures (21 nests/40 ha) and hayfields (13 nests/40 ha). Among hayfields, nesting densities were low in alfalfa (4 nests/40 ha) but higher in red clover (16 nests/40 ha) and mixed grass (18 nests/40 ha). Roseberry and Klimstra (1970) concluded that alfalfa fields, and many red clover fields, lacked sufficient grass cover at ground level to provide acceptable eastern meadowlark nesting habitat.
Wiens (1969) and Herkert et al. (1993) reported that eastern meadowlarks preferred habitats with intermediate levels of vegetation height, density, and cover. Herkert (1994c) found that eastern meadowlark abundance was negatively related to mean grass height. Sample (1989) found that eastern meadowlark abundance was negatively correlated with maximum vegetation height and vegetation height-density and positively correlated with percent litter cover and density of prostrate residual vegetation. Roseberry and Klimstra (1970) believed that the presence of dead grass stems was a prerequisite for use of an area for nesting by eastern meadowlarks. Rotenberry and Wiens (1980) reported positive correlations between eastern meadowlark abundance and vegetation height and density, percent litter cover and depth, and percent grass cover.
In Wisconsin, eastern meadowlark nesting territories were characterized by 74% grass cover, 23% forb cover, 2% bare ground, and 41-cm herbaceous canopy height (Wiens 1969). Mean vegetative characteristics of habitats occupied by nesting eastern meadowlarks in another Wisconsin study (Sample 1989) were 74% herbaceous vegetation cover, 29% litter cover, 5% bare ground, 66-cm maximum vegetation height, and 20-cm vegetation height-density. Height of cover at 204 nest sites in Illinois averaged 38 cm and ranged from 5-79 cm; 67% of all nests were in cover 25-50 cm tall (Roseberry and Klimstra 1970). Wiens (1969) reported that eastern meadowlark nests were surrounded by the tallest, densest vegetation in the breeding territory.
In Ohio, eastern meadowlarks were found in fields devoid of woody vegetation as well as in fields with scattered small trees and shrubs (Peterjohn and Rice 1991). Several researchers found that eastern meadowlarks occupied areas with some low woody vegetation, but avoided areas with dense shrubs or trees (Johnston and Odum 1956; Lanyon 1956a,b; Shugart and James 1973; Burley 1989). Sample (1989) reported a positive correlation between eastern meadowlark abundance and percent woody cover, although occupied habitats were characterized by only 4% tree and shrub cover. Roseberry and Klimstra (1970) found no woody vegetation near nest sites and concluded that shrubs and small trees precluded use of an area by eastern meadowlarks. Wiens (1969) found that eastern meadowlark nesting territories were always close to fences or woodlots. The primary function of fence posts and woody vegetation within eastern meadowlark breeding territories was to serve as singing perches (Wiens 1969, Sample 1989).
Eastern meadowlarks foraged primarily in low (<15 cm tall) grassy cover (Wiens 1969). Major foods of adults during the nesting season included grasshoppers, beetles, grass and forb seeds, and waste grains (DeGraaf and Rudis 1986).
If grasslands are not renewed by some type of disturbance every 3-5 years, their quality as eastern meadowlark nesting habitat will decline (Hays and Farmer 1990, Herkert 1994a). To maintain eastern meadowlark nesting habitat, Hays and Farmer (1990) recommended mowing grasslands no more often than every 3-5 years, during the last 2 weeks of August, and raking to reduce litter accumulation. Mowing during the nesting season (15 Apr-1 Aug) reduced nest success to 26%, compared to 50% on undisturbed grasslands (Roseberry and Klimstra 1970). Herkert (1991, 1994c) reported high densities of eastern meadowlarks on recently mowed grasslands in Illinois and attributed this to the low-to-medium height vegetation on those areas.
Herkert et al. (1993) believed that light grazing, leaving > or equal to 40% vegetative cover > or equal to 25 cm tall, would benefit birds with intermediate vegetation height and density preferences such as the eastern meadowlark. Roseberry and Klimstra (1970) reported an inverse relationship between the intensity of grazing and eastern meadowlark nesting density. Eastern meadowlark density was higher on moderately- (5.6 ha/AUM [animal unit month] ) versus heavily-grazed (2.8 ha/AUM) pastures in south Texas (Baker and Guthery 1990). During a 3-year study in Wisconsin, Lanyon (1957) found 122 eastern meadowlark nests on a 40-ha pasture on which 40-50 head of cattle grazed year-round. He reported a loss of 15 nests (12%) due to cattle trampling. Roseberry and Klimstra (1970) reported that 2 of 120 (2%) eastern meadowlark nests were trampled by cattle and nest success in pastures under various grazing intensities averaged 43%.
Herkert (1991) found high numbers of eastern meadowlarks on recently burned prairie in Illinois, but noted that abundance was similar on grasslands in their first, second, and third or more growing season post-fire. Herkert (1994a), thus, concluded that eastern meadowlark abundance was not influenced by burning. However, Zimmerman (1992) reported that eastern meadowlark abundance was 15% higher on unburned compared to burned tallgrass prairie in Kansas.
Based on data from Missouri and Illinois, Herkert et al. (1993) categorized the eastern meadowlark as moderately sensitive to habitat fragmentation, being most abundant in large grassland tracts but often encountered in small fragments. Its probability of occurrence exceeded 50% only on grasslands >5 ha (Herkert 1994c), more than twice the average nesting territory size of 2.3 ha reported for this species in the Midwest (Wiens 1969). Samson (1980) and Herkert (1991) noted that eastern meadowlarks regularly avoided structurally suitable habitat on grasslands <5 ha and concluded that this species' minimum area requirement was at least 10 ha. Eastern meadowlark incidence on grassland fragments in Illinois was 45% on tracts <20 ha but 100% on grasslands >20 ha (Herkert 1991). Good and Dambach (1943) reported that eastern meadowlarks were more abundant in large, contiguous meadows than in stripped meadows (grassy strips within rowcrops) in Ohio. Ten fields occupied by eastern meadowlarks in southwestern Ohio averaged 14 ha (D. Nolin and J. Ritzenthaler, unpubl. data). Twenty-four CRP grasslands occupied by eastern meadowlarks in Ohio averaged 10 ha and ranged from 1 to 26 ha (Oh. Div. Wildl., unpubl. data).