Eastern Black Rail

The life span for eastern black rail is estimated to be 5 to 9 years.

Pairing may occur from April to August, as documented by L.M. Davidson in 1992. Marsh bird calling activity peaks during the courtship and egg-laying period of spring and early summer, as documented by C.J. Conway in 2009. Nesting in Colorado begins around May 1, which differs from some other states, like Texas, where nesting begins in March (83 FR 50625-50625).

Males and females may select the nest site together, as noted by Cornell University in 2019. Nests are constructed of live and dead emergent, herbaceous plants, like fine grasses, rushes or sedges, often with a dense clump of vegetation that conceals the nest from above. These nests may be dome shaped and have a ramp of dead vegetation on one side, as documented by R.C. Harlow in 1913 and later by R.L. Todd in 1977 and several other researchers. Nests are typically well hidden and positioned over moist soil or shallow water, as documented by R.C. Harlow in 1913 and confirmed by L.M. Davidson in 1992 and several other researchers. Average nest height above the substrate for eastern black rails in Florida was 2.4 inches (6 centimeters), as documented by M.L. Legare and W.R. Eddleman in 2001.

M.L. Legare and W.R. Eddleman also noted that clutch size is seven eggs on average, but can vary from four to 13, as observed by A.C. Bent in 1926 and later confirmed by B. Taylor and B. van Perlo in 1998. Eggs are buffy white, to pinkish white, and dotted with evenly distributed brown spots, as described by A.C. Bent in 1926.

M.L. Legare and W.R. Eddleman noted that pairs have successfully re-nested after initial nesting failed, and C. Hand also noted in 2017 that pairs successfully double brooded. M.L. Legare and W.R. Eddleman also documented that both sexes incubate the eggs for approximately 17 to 20 days. Because both sexes incubate and assist in brood rearing, this species is thought to be monogamous.

During nesting, males have larger home ranges than females, with an average of 3.2 acres (1.3 hectares), and a range of 2.03 to 7.66 acres (0.82 to 3.1 hectares). Home range size for females during nesting averages 1.53 acres (0.62 hectares), with a range of 1.26 to 2.13 acres (0.51 to 0.86 hectares).

L.M. Davidson observed that precocial chicks leave the nest within a day after hatching and are raised by the adults from May through September. Although C. Hand also observed that some chicks fledge as early as mid-June and as late as September. Juveniles obtain immature plumage by 3 months of age, as documented by B. Taylor and B. van Perlo in 1998. At approximately 1 year of age, they obtain breeding plumage and become sexually mature, as documented by W.R. Eddleman and others in 1994.

Eastern black rails are known to eat aquatic beetles, spiders, snails, small crustaceans. To forage, they walk among plants in the shallows, and sometimes in the deeper parts of marshes, and glean insects and other invertebrates from the ground, water or vegetation, as noted by Cornell University and K. Kaufman. Additional prey items include weevils, earwigs, woodlice, grasshoppers and ants. They will also eat seeds of aquatic plants, such as bulrush or cattail, particularly in winter.

Eastern black rails are secretive birds and difficult to detect. In some locations, males will sing throughout the day and night, while in others, for example in Colorado, they sing mostly at night. 

During the breeding and wintering seasons, eastern black rails fly very little. They will typically flush for only a short distance when pursued, as documented by A.C. Bent in 1926, but mostly remain on the ground and run quickly through dense vegetation, as observed by G.L. Armistead in 2001 and other researchers.

Measurements
Adults weigh 1.2 ounces (35 grams) on average

An adult eastern black rail is gray-black in coloration, with white speckled upperparts, and has a grayish crown, a chestnut-colored nape of the neck, and a short tail, as described by Cornell University in 2019. These secretive birds have red eyes, black bills and dusty pink or wine-colored legs. Chicks are covered with a black down that has an oily green sheen, as described by Ridgway and Friedmann in 1941 and later by McMullen in 1944. Juveniles look similar to adults, except their eyes are amber or hazel until 3 months of age, as noted by Cornell University in 2019.

Eastern black rails make multiple vocalizations, but the most commonly heard call is the kic-kic-kerr call (Kellogg 1962), also known as kickee-doo (Robbins et al. 1983, as cited in Davidson 1992a) and ki-ki-krr (Weske 1969). The call is primarily made by adult territorial males and is the main advertisement call (Davidson 1992a). Other calls are grr and churt, which serve as alarm and contact calls; grr (i.e., growling) also is used for territorial defense (Conway 2011). The purpose of the tch call is unknown but may be sounded while on the nest; see Conway 2011 for more call names. Male and female eastern black rails have been shown to respond to playback tapes with significantly different vocalizations (Legare et al. 1999). Males responded with kic-kic-kerr, growling, and churt, 48 percent, 46 percent, and 6 percent of the time, respectively, during 91 playback trails, while females responded with the same calls 5 percent, 29 percent, and 65 percent of the time, respectively, during 43 trials (Legare et al. 1999).

There are substantial regional differences in the daily vocalization patterns for eastern black rail, as documented by C.J. Butler and others in 2015. Birds in Maryland predominately call at nighttime from one to two hours after sunset, to one to two hours before sunrise, as documented by J.S. Weske in 1969 and later by G.B. Reynard in 1974. In 1999, M.L. Legare and others documented that birds in Florida are most vocal at sunset, but will call one to two hours before sunset, to one to two hours after sunrise. In Texas, peak vocalization occurs after sunset until just before midnight and is followed by a second, smaller peak time within two hours of sunrise, as documented by C.J. Butler and others in 2015. The daily vocalization patterns of eastern black rail continue to be an active area of research, as noted by C. Hand in 2017. The Cornell Lab of Ornithology maintains an extensive collection of audio files where you can listen to songs and calls of the eastern black rail.

The eastern black rail is a sparrow-sized, secretive marsh bird, and the smallest rail in North America, as described by W.R. Eddleman and others in 1994. Adults have an average length of 4 to 6 inches (10 to 15 centimeters) and a wingspan of 8.7 to 11 inches (22 to 28 centimeters).

Measurements
Length: 4 to 6 in (10 to 15 cm)
Wingspan: 8.7 to 11 in (22 to 28 cm)

Black rails require dense vegetative cover that allows movement underneath the canopy. Because birds are found in a variety of salt, brackish, and freshwater marsh habitats that can be tidally or non-tidally influenced, plant structure structure
Something temporarily or permanently constructed, built, or placed; and constructed of natural or manufactured parts including, but not limited to, a building, shed, cabin, porch, bridge, walkway, stair steps, sign, landing, platform, dock, rack, fence, telecommunication device, antennae, fish cleaning table, satellite dish/mount, or well head.

Learn more about structure is considered more important than plant species composition in predicting habitat suitability, as documented by R.E. Flores and W.R. Eddleman in 1995. Vegetation height is generally less than or equal to 1 meter in coastal habitats, but taller in occupied cattail and bulrush marshes, as noted by L.M. Davidson in 1992 and later confirmed by M.L. Legare and W. R. Eddleman in 2001 and D.R. Culver and J.M. Lemly in 2013. However, the 2019 species status assessment noted that when shrub densities become too high, the habitat becomes less suitable for eastern black rails. Soils are moist to saturated, occasionally dry, and interspersed with, or adjacent to, very shallow water of 1 to 6 centimeters, as documented by M.L. Legare and W.R. Eddleman in 2001.

Eastern black rail habitat can be tidally or non-tidally influenced, and range in salinity from salt to brackish to fresh. Tidal height and volume vary greatly between the Atlantic and Gulf coasts, and therefore, contribute to differences in salt marsh salt marsh
Salt marshes are found in tidal areas near the coast, where freshwater mixes with saltwater.

Learn more about salt marsh cover plants in the bird’s habitat.

In the northeastern United States, the eastern black rail can typically be found in salt and brackish marshes with dense cover but can also be found in upland areas of these marshes. Further south along the Atlantic coast, eastern black rail habitat includes impounded and unimpounded salt and brackish marshes.

Along portions of the Gulf Coast, eastern black rails can be found in higher elevation wetland zones with some shrubby vegetation. Impounded and unimpounded intermediate marshes, which are marshes that are closer to high elevation areas, also provide habitat for the subspecies. Inland coastal prairies and associated wetlands may also provide habitat for the bird, but are largely uninvestigated.

In Oklahoma, eastern black rails use wet sedge meadows with dense cover. In Colorado, eastern black rails use habitat with shallow wetlands dominated by cattails (Typha spp.), hardstem bulrush (Scirpus acutus var. acutus) and soft-stemmed bulrush (Schoenoplectus tabernaemontani), with willow (Salix spp.) in the overstory, as documented by H.J. Griese and others in 1980. More recent studies by L.E. Wickersham in 2016 found this subspecies to be detected exclusively in extensive cattail marshes with standing water. Additionally, Colorado Parks and Wildlife documented in 2016 that the species is also found in dense emergent vegetation, with a mix of new and residual growth. L. Rossi and J. Runge's 2018 Colorado-based research defined black rail habitat as emergent marsh wetlands that consisted of cattails and other wetland species, like hardstem bulrush (Schoenoplectus acutus).

Soras (Porzana carolina) look similar to eastern black rails, but soras are larger and have a larger yellow bill, as described by Cornell University in 2019. They are overall more brown in coloration than eastern black rails.