Family Furnariidae
ovenbirds

Ovenbirds are New World birds found only in the neotropics. They belong to the order Passeriformes and family Furnariidae. There are 55 genera of ovenbirds and 236 species. Ovenbirds can be found in almost all habitats from rocky intertidal zones to deciduous forest, desert and high alpine areas. They are important members of all bird communities in South America and in some regions they account for 25 percent of all bird species.

Ovenbirds are small to medium sized birds (10 to 26 cm long, 8 to 109 g). Their plumage is primarily shades of brown; however, they often have complex patterns of spots and stripes. Some species have wingbands, tail patches or more brightly colored throat patches. They have very diverse bill and tail structure. Bill shapes and sizes reflect foraging habits. Ovenbird tails are often stiffened and have bare feather tips, modifications that aid the birds in climbing. Males and females look similar, although males may be slightly larger.

Ovenbirds are monogamous, and pairs often remain together from year to year. They are well known for their diverse and often complex nest structures. In fact, the name ovenbird comes from the oven-like structure of some species’ nests.

Although ovenbirds as a group occupy a wide range of habitats, many individual species have very restrictive habitat requirements. Because of these requirements their ranges are often small and fragmented. This, combined with anthropogenic habitat destruction has lead to population declines in many ovenbird species. (Dickinson, 2003; Remsen, 2003; Sibley and Ahlquist, 1990; Skutch, 1996)

Ovenbirds are New World birds found only in the neotropics. They can be found from central Mexico to the southernmost parts of South America. They are also found on Trinidad, Tobago and the Falkland and Juan Fernandez Islands. Their range extends much farther south and to much higher elevations than many other South American bird families. Eighty nine percent of Furnariidae species are endemic to South America. (Remsen, 2003; Roper and Hutson, 2003; Skutch, 1996)

Ovenbirds are found in almost all habitat types. Though their highest diversity is in lowland tropical forest, they are also found in desert, mudflats, coastal sand dunes, saltwater marshes, rocky intertidal zones, bogs, marshes, open areas, scrub, wet cloud forest, urban and agricultural areas. Ovenbirds can be found from sea level to elevations of 4500 meters. Many species are found in areas near water and in rocky areas where rocks are used as foraging substrates or nests sites.

Some species have strict habitat requirements. For example, point-tailed palmcreepers (Berlepschia rikeri) are only found in groves of palm trees which may be small and isolated. Araucara tit-spinetails (Leptasthenura setaria) are restricted to a single tree species, Araucaria angustifolia. (Remsen, 2003; Roper and Hutson, 2003; Skutch, 1996)

Ovenbirds are New World birds found only in the neotropics. They belong to the order Passeriformes and family Furnariidae. Their closest relatives are in the family Dendrocolaptidae (woodcreepers), and there is some discussion of whether woodcreepers should be in their own family or included in Furnariidae. Relationships of groups within the family are unclear; characteristics of nest structure, hind-limb musculature, vocal characters, behavior and plumage have been used to group genera within the family.

Characteristics that distinguish the group include: the syrinx has two pairs of intrinsic muscles, but they do not have horns on the Processi vocales, the middle toe is longer than the outer toe, the outer and middle toes are fused for a short distance only, the inner toe is not longer than the hallux. (Payne, 2003; Remsen, 2003; Sibley and Ahlquist, 1990)

Ovenbirds are small to medium sized birds (10 to 26 cm long, 8 to 109 g). Their plumage is primarily shades of brown. However, they often have complex patterns of spots and stripes. Some species have wingbands and tail patches that can be seen when the birds are in flight. Some have more brightly colored throat patches that can be exposed during displays. Orange-fronted plushcrowns (Metopothrix aurantiaca) are green and yellow, and are the only brightly colored ovenbird.

Ovenbirds have very diverse bill and tail structure. Bill shape and size reflect foraging habits, and range from long, broad and curved to short and straight. Ovenbird tails are often stiffened and have bare feather tips. These modifications in tail morphology aid the birds in climbing. Some species have standard passerine tails and others have very long tails. Ovenbirds' wings are usually short and rounded, although they are occasionally pointed. These birds also have large feet and thick legs. The bill, legs and feet are dark in most species.

Male and female ovenbirds look similar, although males may be slightly larger. Juveniles are colored differently than adults and tend to be more cryptic. Molting does not change the appearance of adult birds. Ovenbirds give off a unique musty odor that is thought to come from the oil in the uropygial gland. It is not known if the smell has any function, but it may help repel ectoparasites. (Remsen, 2003; Roper and Hutson, 2003; Skutch, 1996)

There is no information about lifespan/longevity for ovenbirds. Annual adult survival has been estimated to be about 71 percent. (Remsen, 2003)

Some species of ovenbirds are migratory, others are sedentary. Birds living at high elevations may make altitudinal movements as seasons change. They are usually found in pairs. However, some species form mixed-species feeding flocks during the non-breeding season and may migrate in groups. They are territorial and defend their territories with song, wing flapping displays, feather fluffing, exposing bright throat patches and raising crown feathers. Territories range in size from 0.23 to 1 hectare.

Ovenbirds are diurnal. They sing most often at dawn, but will sing throughout the day. At night they roost in burrows, holes or nests. They have been seen sunning themselves and anting. (Remsen, 2003; Skutch, 1996)

Most species of ovenbird sound similar. Their calls have been described as unmusical and harsh. Their calls are loud, but simple, and composed of buzzy notes of varying speeds that rise and fall in pitch. Pairs will sing in duets to defend territories and strengthen the pair-bond. Chicks use a begging call to solicit feeding by adults.

Ovenbirds have numerous displays that they use in attracting mates and defending territories. Displays include: exposing bright throat patches, raising crown feathers and lifting their wings to show their wingstripes. (Remsen, 2003; Skutch, 1996)

Ovenbirds feed primarily on arthropods and other invertebrates. Their main insect prey include: Orthoptera (grasshoppers and relatives), Hymenoptera (they eat ants only within this group), Coleoptera (beetles) and larval Lepidoptera (butterflies and moths). Species that live in aquatic habitats will eat non-arthropod invertebrates such as mollusks and worms. Occasionally ovenbirds will eat small frogs, lizards, bird eggs, crabs, seeds and fruit.

Ovenbirds' bill shapes and sizes reflect the foraging habits of each species. Ovenbirds display a diversity of feeding strategies including: hanging upside-down to reach under leaves, probing, gleaning, wading in shallow water, looking for insects in bark and sifting through the leaf litter. Their tails are modified to help them climb trees in search of food (see Physical Description). Ovenbirds will use their feet to hold down their prey while they eat it. This behavior is uncommon among Passeriformes. (Remsen, 2003; Skutch, 1996)

Other than owls (family Strigidae), few predators of adult ovenbirds are known. Nest predators include: snakes (suborder Serpentes), Guira cuckoos (Guira guira), roadside hawks (Buteo magnirostris), black-chested buzzards (Geranoaetus melanoleucus) and opossums (family Didelphidae). Ovenbirds’ primary defense against nest predators is the design of their nests. Nests are often hidden in cavities or tunnels, or if they are exposed, they are protected by thorns or cacti. (Remsen, 2003; Skutch, 1996)

Other animals such as insects (for example beetles and social wasps), rodents, lizards, snakes, frogs and other birds use ovenbird nests for shelter or breeding. Ovenbirds themselves, however, do not usually re-use nests. Botfly larvae (Gasterophilidae) often attack nestlings as do other nest parasites (Hemiptera, Psammolestes, Triatoma and Acarina). Ovenbirds impact the populations of the prey species they eat. They are also hosts to introduced nest parasites, shiny cowbirds (Molothrus bonariensis) (Remsen, 2003)

Ovenbirds sometimes build nests on electrical poles and cause damage to electrical systems. (Remsen, 2003)

Ovenbirds eat insects that are crop pests in agricultural areas. They are also sought out by birdwatchers. (Remsen, 2003)

Anthropogenic habitat destruction is the main threat to ovenbirds today. Deforestation, burning, grazing and increases in agriculture all reduce and fragment ovenbird habitat. Many ovenbird species have very narrow habitat requirements. These species are particularly vulnerable to habitat destruction and fragmentation because they are not able to move to new habitat when theirs is destroyed. Currently the IUCN lists 3 species of ovenbird as “Critically Endangered”, 9 species as “Endangered”, 15 as “Vulnerable” and 18 as “Near Threatened”. Species that live in areas that are undesirable to humans (for example, high alpine habitats) are doing well and some species are able to adapt to moderate disturbance levels. Species that live in urban areas are also doing well and are extending their ranges as urban areas expand.

Ovenbirds are also suffering as a result of introduced species. House sparrows (Passer domesticus) take over their nest sites and shiny cowbirds (Molothrus bonariensis) parasitize their nests. (IUCN, 2003; Remsen, 2003; Skutch, 1996)