This article uses the IOC/NACC/HBW genus. The IOC, HBW, and Clements agree that the paint-billed crake has two subspecies, the nominateN. e. erythrops and N. e. olivascens.[3][4][2]
Description
The paint-billed crake is 18 to 20 cm (7.1 to 7.9 in) long and weighs about 40 to 70 g (1.4 to 2.5 oz).[10] One specimen had a wing of 20 cm (7.9 in), a tarsus of 2.8 cm (1.1 in), and weighed 43 g (1.5 oz).[11] The species gets its common name from its red and yellow bill; it has bright red legs. The sexes are alike. The nominate subspecies has a brown crown, nape, and upperparts including the tail. Its throat is white and its face, throat, and breast are gray. Its flanks, belly, and vent are barred black and white. N. e. olivascens is similar but darker and with less white on its throat.[10]
The species inhabits a wide variety of landscapes, from the very wet like reedbeds and marshes, to wet and dry pastures and rice fields, fairly dry bushy areas, and (in the Galápagos) humid woodlands. In South America it seems partial to swamp and savanna habitats with much grass and thickets. In elevation it ranges from near sea level to almost 3,400 m (11,200 ft)[10]
There is no evidence that the paint-billed crake makes regular movements. However, it has been found many times far outside its normal range, so it is at least prone to vagrancy and might have migratory populations.[10] It does not respond to playback.[12]
Feeding
Little is known about the paint-billed crake's feeding habits or diet. It is known to eat invertebrates including Diplopoda and Coleoptera and also seeds. It forages in soil, leaf litter, and standing water, and at dawn and dusk has been noted feeding in open areas next to dense vegetation.[10]
Breeding
The paint-billed crake's breeding season varies widely across its range. It builds a bowl nest of green grass on or near the ground and at least partially hidden in grass. It lays a clutch of three to seven eggs; they are creamy buff and have large reddish blotches near the blunt end. The incubation period is at least 23 to 25 days.[10][13]
The paint-billed crake's song is "a long, gradually accelerating series of up to 36 staccato somewhat yelping 'kjek' notes". Its calls include "frog-like, guttural, buzzy, single notes", "a mellow soft purring", and "a sharp 'twack'".[10]
Status
The IUCN has assessed the paint-billed crake as being of Least Concern. It has a very large range but its population size and trend are unknown. No immediate threats have been identified.[1] The species is "very furtive and difficult to observe" so its abundance and even its exact range limits are hard to determine. Its "status and distribution need investigation, as do movements and breeding".[10]
^ abcClements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, J. A. Gerbracht, D. Lepage, B. L. Sullivan, and C. L. Wood. 2021. The eBird/Clements checklist of Birds of the World: v2021. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ Retrieved August 25, 2021
^ abcdChesser, R. T., S. M. Billerman, K. J. Burns, C. Cicero, J. L. Dunn, B. E. Hernández-Baños, R. A. Jiménez, A. W. Kratter, N. A. Mason, P. C. Rasmussen, J. V. Remsen, Jr., D. F. Stotz, and K. Winker. 2022. Check-list of North American Birds (online). American Ornithological Society. https://checklist.aou.org/taxa
^ abRemsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 24 July 2022. Species Lists of Birds for South American Countries and Territories. https://www.museum.lsu.edu/~Remsen/SACCCountryLists.htm retrieved July 24, 2022
^Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 24 July 2022. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved July 24, 2022
^ abcdefghiTaylor, B., A. Bonan, P. F. D. Boesman, and C. J. Sharpe (2020). Paint-billed Crake (Mustelirallus erythrops), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.pabcra.01 retrieved October 12, 2022
^Osborn, David; Beissinger, Steven R. (1979). "Paint-Billed Crake in Guyana"(PDF). The Auk. 96 (2): 425. Retrieved October 12, 2022.
^Dvorak, Michael (June 2017). "Conservation Status of Landbirds on Floreana: the Smallest Inhabited Galapagos Island". Journal of Field Ornithology. 88 (2): 132–145. doi:10.1111/jofo.12197.