Tinamous (Tinamidae)

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Tinamous

(Tinamidae)

Class Aves

Order Struthioniformes

Suborder Tinami

Family Tinamidae


Thumbnail description
Small to medium-sized ground-dwelling birds with fully developed wings and capable of flight; cryptically colored in grays and browns, with three or four toes

Size
8–21 in (20–53 cm), 0.09–5 lb (43–2,300 g)

Number of genera, species
9 genera; 47 species

Habitat
Rainforest, secondary forest, savanna woodland, montane steppe, grassland, and cropland

Conservation status
Critically Endangered: 2 species; Vulnerable: 5 species; Near Threatened: 4 species

Distribution
South and Central America, as far north as Mexico

Evolution and systematics

In older natural history books, the description of birds usually began with ratites, including rheas, ostriches, cassowaries, kiwis, and the extinct moas and elephant birds of Madagascar. Because these large flightless birds have no keel on the sternum (breastbone), they are known as flat-chested birds, in contrast to all modern keel-breasted (Carinatae) birds. Today we know that the ratites descended from flying keel-breasted ancestors. Tinamous (Tinamidae) are a still-living primitive bird family that may be close to the ancestral group of ratites.

Physical characteristics

Length 8–21 in (20–53 cm), weight 0.09–5 lb (43–2,300 g). Tinamous are ground birds with a compact form, a slender neck, a small head, and a short, slender bill that curves slightly downward. The wings are short and capacity for flight is poor. The feet are strong; there are three well-developed forward toes, and the hind toe is in a high position and either retrogressed or absent. The tail is very short and in some species it is hidden under tail coverts; this and abundant rump feathering give the body a rounded shape. Powder down and a preen gland are present. In contrast to gallinaceous birds, they do not scratch for food with their feet, but do use their feet to dig nest scrapes. A copulatory organ is present. The plumage is inconspicuous, although crown feathers of some species can be raised as a crest. Males and females have similar plumage, or females may be somewhat brighter in color and often larger than males.

Distribution

The range of tinamous has not changed significantly in recorded time. They live in tropical parts of Central and South America. In the north they live only slightly beyond the tropic of Cancer (Zimttao in northwest Mexico), but in South America they are widespread, distributed throughout the continent. One species has been successfully introduced to Easter Island in the Pacific.

Habitat

Many species live in dense forest, especially those in the genera Tinamus, Nothocercus, and Crypturellus. Other species live in savanna, on grassland, and in the montane or puna regions, at high altitudes. Some grassland forms have established themselves successfully in cropland; others can live on ranches among grazing cattle.

Behavior

Walking or running, tinamous move almost exclusively on the ground. When approached by people, they hide in thick ground cover or steal away unobserved. When hard-pressed in open country, they crawl into holes dug by other animals. Some species are very reluctant to fly. When surprised by a larger animal or when followed too closely, they rise suddenly with loud, frightening wing beats, and often they call. They disappear swiftly and alight in thick vegetation. Before a surprised hunter can bring up his gun, they have disappeared.

The initial burst of wing fluttering is often followed by a long glide and again by renewed wing beats. Although many tinamous cover long distances on foot rather than in flight, D. A. Lancaster observed a brushland tinamou (Nothoprocta cinerascens) that regularly flew 660 ft (200 m) from nest to feeding place. In other species, flights of 660–4,900 ft (200–1,500 m) have been observed. In Patagonia, the elegant crested tinamou (Eudromia elegans) forms strings of six to 30 or more birds. But most adult tinamous live singly except during the reproductive season. Many tinamous roost on the ground, but in some—especially those in the genus Tinamus—the hind surface of the tarsus is rough. These birds roost in trees, squatting with the tarsus across a branch rather than gripping the branch with their toes as songbirds do.

Hearing tinamou calls is one of the most unforgettable experiences one can have in tropical America. In contrast to most tinamous, the male highland tinamou (Nothocercus bonapartei) utters a rough crowing or barking call that can be heard for several miles (kilometers) through mountain forests. In some species, males and females are distinguishable by their calls. Tinamous sing mainly during the breeding season; they are noisiest in early morning and late evening. When startled, they fly off or follow one another, hoarsely shrieking or crowing.

Feeding ecology and diet

Tinamous eat mainly small fruits and seeds that they pick from the ground or from plants they can reach from the ground; they may jump up 4 in (10 cm) to reach a particularly tempting fruit. Seeds with wing-like appendages that make swallowing difficult are beaten against the ground or vigorously shaken. They also eat opening buds, tender leaves, blossoms, and even roots. For variety they catch insects and their larvae, worms, and, in moist places, mollusks. They swallow small animals whole; they first peck at larger ones, then shake them or beat them against the ground. When searching for food, they scatter fallen leaves and other ground cover with their bills, but do not scratch with their feet. When searching for worms or larvae in moist places, many species fling the earth aside with their bills, digging down 0.7–1.2 in (2–3 cm).

Reproductive biology

In ornate and highland tinamous, and in taos and many other species, there are about as many females as males. But in the variegated tinamou there may be four times as many males as females.

Reproductive behavior differs from that of most other birds. Only males care for eggs and young. In the few species that are adequately studied, males live in polygyny and females in polyandry. A male in breeding condition attracts two, three, or more females by continually calling. Females lay in the same nest and leave incubation to the male. Females leave to lay eggs in the nests of other males. When the male has raised his young or lost the eggs, he begins to call again and attracts new hens that supply him with another nest full of eggs. This breeding behavior has been observed in such different species as the highland tinamou, the brushland tinamou, and the slaty-breasted tinamou (Crypturellus boucardi). The variegated tinamou (Crypturellus variegatus) cares for only a single egg; the clutch of four to nine eggs incubated by the male ornate tinamou (Nothoprocta ornata) seems to come from a single female. In this mountain species, the

larger and more aggressive female defends the breeding territory; in other tinamous this is done by males.

Tinamous almost always nest on the ground, often in densest herbage or between projecting root buttresses of large trees. Many tinamous lay their eggs directly on the ground or on leaves that happen to be on the chosen spot. Ornate tinamous build a proper nest base of dry earth, or a mixture of earth and moss turf. On this they erect a firm structure of grass that is worked into the base to form a circle. Shiny tinamou eggs are among the most beautiful natural products known. They may be green, turquoise blue, purple, wine red, slate gray, or a chocolate color, and often have a purple or violet luster. They are always uniformly colored, without spots or blotches. Their shape is oval or elliptical.

Incubating male tinamous sit continuously on eggs for many hours. In most species they leave the clutch once a day to look for food, usually during mornings or in the afternoon, depending on the weather, and are away from the nest for 45 minutes up to five hours.

Although the eggs are conspicuous and have no protective coloration, some tinamous do not cover the eggs when leaving the nest. A brushland tinamou covers its eggs only when they are about to hatch. The ornate tinamou regularly covers the eggs with feathers, giving them some protection from the harsh climate in the 13,000-ft (4,000-m) Peruvian puna. In the warm forests of Central America, a slaty-breasted tinamou always threw leaves toward the nest quite carelessly; often more than half the eggs were left uncovered.

Incubating tinamous sit so firmly on the nest that one can approach very closely. Although they will not let themselves be touched by a hand, an observer can sometimes touch them with the end of a long stick. If someone approaches, some species—including the ornate tinamou and several Crypturellus species—press head and body close to the ground and raise the hind end, sometimes until the stumpy tail and lower tail coverts stand almost vertically. This posture resembles that assumed by certain tinamous in courtship display or when they are alarmed while walking. It seems to serve no special purpose in the incubating cocks, because raising the hind end may expose the shiny eggs. If one approaches an incubating tinamou cock too closely, it flies off the nest and out of sight in a burst of speed. An exception is the tataupa (Crypturellus tataupa), which flutters over the ground as if hurt and unable to fly when displaced from its eggs.

Newly hatched tinamous are densely covered with long soft down that in some species is marked in dulled colors. On the first day after hatching, the male leads the young out of the nest, moving slowly and calling them with repeated soft whistles or whining tones. Now and then he picks up an insect from the ground and moves it in his bill, then lays the insect before one of the young to be picked up. On leaving the nest, chicks of the small tinamous are very delicate, but they move so skillfully through the dense vegetation that little is known about them after they leave the nest. They probably develop rapidly and soon leave their father. A slaty-breasted tinamou at 20 days differed little in color and size from adults.

Conservation status

Eleven species are threatened, mainly because clearing and development have fragmented their habitats. The rarest are the Magdalena tinamou (Crypturellus saltuarius), known from one specimen, and Kalinowski's tinamou (Nothoprocta kalinowskii), not seen for many years. Both of these species are considered Critically Endangered by the IUCN. The dwarf tinamou (Taoniscus) and the lesser nothura (Nothura minor) are badly affected by development—IUCN considers these species Vulnerable. Three other species with very small ranges are also considered Vulnerable—the black tinamou (Tinamus osgoodi), the Choco tinamou (Crypturellus kerriae), and Taczanowski's tinamou (Nothoprocta taczanowskii). Four additional species are listed as Near Threatened—the yellow-legged tinamou (Crypturellus noctivagus), the pale-browed tinamou (Crypturellus transfasciatus), the Colombian tinamou (Crypturellus columbianus), and the solitary tinamou (Tinamus solitarius).

Significance to humans

Tinamous are hunted for food by humans throughout their range. A Brazilian rural family consumed about 60 nothuras a year, but this is not thought to be too severe a drain on the birds. Many attempts have been made to introduce the birds to other parts of the world, so far, except for Easter Island, without success.

Species accounts

List of Species

Black tinamou
Great tinamou
Highland tinamou
Thicket tinamou
Slaty-breasted tinamou
Variegated tinamou
Red-winged tinamou
Brushland tinamou
Spotted nothura
Elegant crested-tinamou

Black tinamou

Tinamus osgoodi

taxonomy

Tinamus osgoodi Conover, 1949, Curzo, Peru. Two subspecies.

other common names

French: Tinamou noir; German: Schwartztinamu; Spanish: Tinamú Negro.

physical characteristics

17 in (43 cm). Females are slightly larger. Sooty brown belly; vent is chestnut with black speckling.

distribution

Known only from two restricted and widely separated localities—the upper Magdalena valley in southern Colombia (sub-species T. o. hershkovitzi) and the Marcapata valley in southeastern Peru (T. o. osgoodi).

habitat

Humid, high-altitude tropical forest, 5,000–7,000 ft (1,500–2,100m), where epiphytes, tree ferns, bromeliads, and moss abound.

behavior

The call is a simple, descending whistle.

feeding ecology and diet

Not known.

reproductive biology

The only nest found was on the ground and contained two glossy blue eggs.

conservation status

Vulnerable. Threatened by habitat destruction.

significance to humans

None known.


Great tinamou

Tinamus major

taxonomy

Tinamus major Gmelin, 1789, Cayenne.

other common names

English: Mountain hen; French: Grand tinamou; German: Großtinamu; Spanish: Tinamú Oliváceo.

physical characteristics

17.5 in (44 cm), 2.5 lb (1.1 kg). Female slightly larger. Overall color ranges from light to dark olive brown. Whitish on throat and center of belly.

distribution

Widely distributed, with seven subspecies in Belize, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, Guatemala, French Guiana, Honduras, Mexico, Nicaragua, Panama, and Venezuela.

habitat

Dense tropical and subtropical forest, preferably with an open floor, at altitudes of 1,000–5,000 ft (300–1,500 m).

behavior

Usually solitary, maintaining a home range. The call is a series of musical, tremulous whistles.

feeding ecology and diet

Feeds on the forest floor, taking fruits and seeds, especially of the Lauraceae, Annonaceae, Myrtaceae, and Sapotaceae.

reproductive biology

The breeding season is long, extending from mid-winter to late summer. The nest, built between buttresses of a forest tree, contains 3–6 glossy turquoise or violet eggs. The male alone incubates eggs and rears the brood.

conservation status

Not threatened.

significance to humans

It is hunted as a game bird, especially around towns, but has survived better than other game species. The great tinamou has various roles in native American folklore in Brazil, Colombia, and Panama.


Highland tinamou

Nothocercus bonapartei

taxonomy

Nothocercus bonapartei Gray, 1867, Aragua, Venezuela. Five sub-species.

other common names

English: Bonaparte's tinamou; French: Tinamou de Bonaparte; German: Bergtinamu; Spanish: Tinamú Serrano.

physical characteristics

15 in (38.5 cm), 2 lb (925 g). Mottled or barred with black and cinnamon on back and wings. Throat is variable rufous color.

distribution

Colombia, Costa Rica, Panama, and Venezuela.

habitat

Tropical and subtropical forest, mainly above 5,000 ft (1,500 m), favoring damp areas, especially those with bamboo thickets.

behavior

The call is loud and hollow, repeated many times, given by the male from his home range, which he occupies throughout the year.

feeding ecology and diet

Feeds on fallen fruits and small animals.

reproductive biology

The male defends a small territory in his home range, attracting one or more females with calls and a display known as "follow feeding." The nest, which may contain eggs from several

females in a clutch of four to 12, is concealed in ground vegetation. Incubation is by the male alone.

conservation status

Not threatened.

significance to humans

Hunted as a game bird; populations in Costa Rica and Peru have declined as a result.


Thicket tinamou

Crypturellus cinnamomeus

taxonomy

Crypturellus cinnamomeus Lesson, 1842, La Union, El Salvador.

other common names

English: Rufescent tinamou; French: Tinamou cannelle; German: Beschtinamu; Spanish: Tinamú Canelo.

physical characteristics

10.8 in (27.5 cm), 1 lb (440 g). Barred black on back and flanks; white throat and cinnamon or rufous cheeks and breast.

distribution

This tinamou, with nine subspecies, is widespread in Central America and has populations in Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, and Nicaragua. Its distribution extends farther north than that of any other tinamou.

habitat

Thick undergrowth, with an overstory—a foliage layer in a forest canopy including the trees in a timber stand—ranging from arid scrub to secondary forest.

behavior

The monotonous call sounds like a steam whistle when heard at close quarters. The bird lives singly, in pairs, or in family parties. When disturbed it walks, rather than flies, away.

feeding ecology and diet

Feeds on fruit, seeds, and insects, searching for food in small parties that attract attention by crackling dry leaves as they feed.

reproductive biology

The nest is placed on the ground at the base of a tree. The clutch is usually three, but may be up to seven glossy purplish eggs. Hybrids have been found between this species and the slaty-breasted tinamou.

conservation status

Not threatened.

significance to humans

Because it is so unwilling to fly, it is not regarded as an important game bird.


Slaty-breasted tinamou

Crypturellus boucardi

taxonomy

Crypturellus boucardi Sclater, 1859, Oaxaca, Mexico. Two sub-species.

other common names

English: Boucard tinamu; French: Tinamu de Boucard; German: Graukehltinamu; Spanish: Tinamú Pizarroso.

physical characteristics

10.8 in (27.5 cm), 1 lb (470 g). Pink to bright red legs; slaty breast, blackish head, and white throat. Back is blackish to chestnut. Female has barring on wings.

distribution

Belize, Costa Rica, Guatemala, Honduras, Mexico, and Nicaragua.

habitat

Sea level to 6,000 ft (1,800 m), sometimes favors thick undergrowth. Also humid forest with little undergrowth at ground level. Sometimes common in regenerating plantations and is often in damp areas, especially near forest edges.

behavior

The call has three notes and is lower than the calls of many tinamous. It may be given in long bouts, up to five hours in one case. Calls of individual males are recognizable, and mellower and less variable than female calls. It is solitary, remaining in its home range throughout the year.

feeding ecology and diet

Feeds on fruits and seeds, tossing leaves aside with its bill in its search. It takes insects, including ants and termites.

reproductive biology

In the breeding season it establishes a small territory in its home range, attracting two to four females to lay in a nest at the base of a tree or in thick vegetation. The male alone incubates; females leave to mate with another male.

conservation status

Not threatened.

significance to humans

Hunted as a game bird and has become rare in some of its range, but is elsewhere still common.


Variegated tinamou

Crypturellus variegatus

taxonomy

Crypturellus variegatus Gmelin, 1789, Cayenne.

other common names

French: Tinamou varié; German: Rotbrusttinamu; Spanish: Tinamú Abigarrado.

physical characteristics

11.5 in (29.5 cm), 0.8 lb (380 g). Black head; neck and breast rufous. Light barring on underparts.

distribution

Belize, Brazil, Colombia, Ecuador, Guiana, Peru, and Venezuela.

habitat

Tropical forest with dense undergrowth at moderate altitudes, 300–4,300 ft (100–1,300 m).

behavior

The call is a series of five evenly pitched tremulous notes, often merging to a trill, with the first note descending and distinct from the rest of the trill.

feeding ecology and diet

Mainly seeds and fruits, with few insects.

reproductive biology

The female establishes a territory, attracts a male, lays one egg in a rudimentary nest, and leaves the male incubating while she departs to establish another territory and repeat the process.

conservation status

Not threatened.

significance to humans

The bird does not appear to be important as a game species.


Red-winged tinamou

Rhynchotus rufescens

subfamily

Rhynchotinae

taxonomy

Rhynchotus rufescens Temminck, 1815, São Paulo, Brazil. Four subspecies.

other common names

French: Tinamou isabelle; German: Pampahuhn; Spanish: Tinamú Alirrojo.

physical characteristics

16 in (41 cm), 1.8 lb (830 g). Female slightly larger. Black patch on crown; rufous primaries. Light grayish brown to whitish underneath. May be black barring on flanks, abdomen, and vent.

distribution

Argentina, Bolivia, Brazil, Paraguay, and Uruguay.

habitat

At low altitudes, below 3,300 ft (1,000 m), it lives in damp grassland and woodland edges; at higher altitudes it is found in semiarid scrub and cereal fields.

behavior

The call, given only by males, is a long, ringing single whistle followed by shorter, mournful whistles. The birds live dispersed in the dense vegetation, and are most active in the heat of the day.

feeding ecology and diet

It is sedentary, feeding on the ground on seeds, tubers, and fruit. In the summer it takes more animal food, including earthworms, termites, and other insects. It digs for food with its bill, and so is unpopular on newly sown cropland.

reproductive biology

The red-winged tinamou has many displays, the male attracting one or more females by follow feeding, and always accompanies the female to the nest when she is to lay. He alone incubates the eggs and broods the chicks.

conservation status

Not threatened.

significance to humans

A popular game bird and hunted out in some regions, but elsewhere common. Because it will live in cropland it has extended its range alongside agricultural development.


Brushland tinamou

Nothoprocta cinerascens

taxonomy

Nothoprocta cinerascens Burmeister, 1860, Tucumán, Argentina. Two subspecies.

other common names

French: Tinamou sauvageon; German: Cordobasteißhuhn; Spanish: Tinamú Montaraz.

physical characteristics

12.5 in (31.5 cm), 1.2 lb (540 g). Female slightly larger and darker. Black barring on back and wings.

distribution

Argentina, Bolivia, and Paraguay.

habitat

Favors dry savanna woodlands, usually below 3,300 ft (1,000 m), but will live in cropland and open thorn scrub.

behavior

The advertising call is a series of seven to 10 clear whistled notes with considerable carrying power. Home ranges are about 50 acres (20 ha), maintained mainly by calls but often overlapping ranges of other males.

feeding ecology and diet

Feed on the ground, mostly on insects and small animals, but also take some fruit.

reproductive biology

Males attract groups of two to four females, establish a nest site, and supervise females while they lay in it. When the females leave to join another male, the original male incubates the clutch and rears the brood alone.

conservation status

Not threatened.

significance to humans

Subject to light hunting but remains common.


Spotted nothura

Nothura maculosa

taxonomy

Nothura maculosa Temminck, 1815, Paraguay. Eight subspecies.

other common names

French: Tinamou tacheté; German: Fleckensteißhuhn; Spanish: Tinamú Manchado.

physical characteristics

10 in (25.5 cm), 0.6 lb (250 g). Female slightly larger. Variable appearance, sometimes very dark upperparts.

distribution

Argentina, Brazil, and Uruguay.

habitat

Most subspecies inhabit lowlands, living in open grassland, shrub steppe, and cropland. Its range is expanding as clearing takes place for agriculture.

behavior

The call is a series of brief, high-pitched piping notes, often given in response to other calling birds. Populations may be very dense in favorable country, up to a bird to every 2.5 acres (1 ha).

feeding ecology and diet

The spotted nothura feeds on vegetable and animal matter, taking more insects than plants in Argentina, but elsewhere feeding mainly on seeds, including those of pasture plants, crops, and weeds.

reproductive biology

The species has a very high reproductive rate; females can mature at two months of age and have 5–6 broods in a year. Males take longer to mature, or at least to establish nests. As with other tinamous, males undertake all incubation and parenting, often attracting more than one female to lay in a single nest.

conservation status

Not threatened.

significance to humans

A very popular game bird, but a high reproductive rate and early maturity ensure that it remains common.


Elegant crested-tinamou

Eudromia elegans

taxonomy

Eudromia elegans Geoffroy St. Hillaire, 1832, South America. Eight subspecies.

other common names

French: Tinamou élégant; German: Perlsteißhuhn; Spanish: Martineta Común.

physical characteristics

15.5 in (39 cm), 1.3 lb (600 g). Leg color pale bluish to grayish brown. Lacks hind toe. Crest is long, normally carried backwards.

distribution

Throughout Argentina and Chile.

habitat

Arid and semiarid grassland and savanna, favoring open sites, ranging from sea level to 8,000 ft (2,500 m) in altitude.

behavior

The call is a loud melancholy whistle. Unlike many tinamous, this species forms small flocks, especially in winter when it invades alfalfa crops. In spring and summer it may still be found in pairs and small groups.

feeding ecology and diet

In winter it feeds mainly on seeds and leaves of plants; in summer it takes many insects and invertebrates, including termites.

reproductive biology

Breeding systems are polyandrous and polygynous, although males undertake all incubation and parenting.

conservation status

Not threatened.

significance to humans

It is hunted intensely and remains common only in remote areas.


Resources

Books

Davies, S. J. J. F. Ratites and Tinamous. Oxford: Oxford University Press, 2002.

del Hoyo, J., A. Elliot, and J. Sargatal, eds. Handbook of the Birds of the World. Vol. 1, Ostrich to Ducks. Barcelona: Lynx Editions, 1992.

Lancaster, D. A. "Life History of the Boucard Tinamou in British Honduras." Condor 66 (1964): 165–81, 253–76.

Lancaster, D. A. "Biology of the Brushland Tinamou Nothoprocta cinerescens." Bulletin of the American Museum of Natural History 127 (1964): 271–314.

Periodicals

Beebe, W. "The Variegated Tinamou Crypturus variegatus (Gmelin)." Zoologica 6 (1925): 195–227.

S. J. J. F. Davies, ScD