Andean Coot

The Andean coot (''Fulica ardesiaca''), also known as the slate-colored coot, is a species of bird in subfamily Rallinae of family Rallidae, the rails, gallinules, and coots. It is found in Argentina, Bolivia, Chile, Colombia, Ecuador, and Peru.HBW and BirdLife International (2021) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 6. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v6_Dec21.zip retrieved August 7, 2022Remsen, 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

Taxonomy and systematics

The Andean coot has two subspecies, the nominate ''F. a. ardesiaca'' and ''F. a. atrura''. They have a somewhat tortuous taxonomic history. The nominate was at one time treated as a subspecies of the American coot (''F. americana'') and the other as a separate species. Later they were both included as subspecies of the American coot. The currrent treatment has been widely accepted since the 1980s, but there is some speculation that the subspecies might be full species.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, 2022Taylor, B. (2020). Slate-colored Coot (''Fulica ardesiaca''), 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.slccoo1.01 retrieved November 24, 2022

Description

The Andean coot is long. It has two color morphs that are present in both subspecies. Both morphs are mostly slaty gray that is blacker on the head and neck. Their secondaries usually have white tips. One morph has a chrome yellow bill that is paler yellow and sometimes green on the tip, a deep chesnut frontal shield, and green legs and feet. The other has a white bill, a white to orange-yellow frontal shield, and slaty legs and feet. Independent of the color morphs, the subspecies differ only in the color of their undertail coverts: The nominate's are white and those of ''F. a. atrura'' are almost black.

Distribution and habitat

The nominate subspecies of Andean coot is found in the Andes from northern Peru south through western Bolivia into northern Chile as far as the Antofagasta Region and into northwestern Argentina as far as Catamarca Province. ''F. a. atrura'' is found from the Andes of southern Colombia through Ecuador into far northern Peru and also in coastal Peru. Fossils tentatively assigned to this species are known from the Laguna de Tagua Tagua formation of Chile.

The Andean coot mostly inhabits large lakes with heavily vegetated shallows, though it also is found in sparsely vegetated lakes and in ponds, marshes, and rivers. Red-fronted birds tend to dominate in vegetated lakes and white-fronted ones in the less vegetated higher elevation ones. The nominate subspecies is found at elevations between . ''F. a. atrura'' is found between in Colombia and at lower elevations in Ecuador and Peru.

Physiology

Populations of Andean coots that live at high elevations have adapted physiologically to a low-oxygen environment. Those living higher have more capillaries per square millimeter of muscle compared to those living at sea level.

Behavior

Movement

Andean coots make some seasonal movements but they have not been defined.

Feeding

The Andean coot's diet is mostly aquatic vegetation. '' Chara'' is a main component, especially in higher elevation lakes, but others include ''Myriophyllum'' and ''Elodea''. It feeds by diving as deep as and also by walking on floating vegetation. It is gregarious when not breeding and often feeds with other species of coots.

Breeding

The Andean coot's breeding season varies geographically. It may breed at any time of year but most egg laying is in the July-August dry season. It is monogamous and when breeding it is aggresive and territorial. Mixed pairs of the two color morphs often occur. Nests are constructed among reeds or on floating vegetation. Most clutches are of four or five eggs.

Vocalization

The Andean coot's usual call is "a low 'churr' or harder 'hrrp'" that is often repeated. Females make a "low chitter".

Status

The IUCN has assessed the Andean coot as being of Least Concern. It has a large range, but its population size and trend are not known. No immediate threats have been identified. It is considered "locally common to abundant, sometimes assembling in thousands."

Gallery

Image:Andean Coot RWD3.jpg, Red-fronted morph
Image:Andean Coot RWD6.jpg, White-fronted morph
image:FulicaArdesiacaSmit.jpg, Illustration by Joseph Smit, 1869

References

{{Taxonbar, from=Q1262940

Andean coot
Birds of the Andes
Birds of the Ecuadorian Andes
Birds of the Altiplano
Andean coot
Andean coot
Taxonomy articles created by Polbot