Penduline Titmice (Remizidae)

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Penduline titmice

(Remizidae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Remizidae

Thumbnail description
A variable group of small passerines with short wings and tails, and delicate heads. Plumage is uniform and dull-colored in both males and females. Bill is not curved but straight

Size
3–4.3 in (7.5–11 cm); 0.16–0.44 oz (4.6–12.5 g)

Number of genera, species
4 genera; 10 species

Habitat
Varied: deserts, wetlands, scrub and forest

Conservation status
Not threatened

Distribution
Wide distribution from Africa through Europe and into Asia; one species in North America

Evolution and systematics

There are 10 species of penduline tit in four genera, according to Peters (1934–1986). However, classification is problematic. Traditionally they are placed in their own family, the Remizidae, but more recent classification based on DNA analysis suggests they may be better placed as a subfamily (Remizinae) in a larger Paridae family, which also includes the true tits, i.e. chickadees (Sibley and Ahlquist 1990).

Physical characteristics

The penduline tits are small passerines ranging in length from the 3 in (75 mm) tit-hylia (Pholidornis rushiae) to the larger 4.3 in (110 mm) European penduline tit (Remiz pendulinus). Their color and form is quite variable, reflecting the group's diversity. Upper parts range from gray to chestnut, to olive green, and underparts from white to yellow. Some, such as those in the Remiz genus, show distinctive black masks. The African penduline tits (genus Anthroscopus) are similar to leaf warblers (Sylviidae). Tail length is variable; some of the African penduline tits and fire-capped tits (Cephalopyrus flam-miceps) have quite short tails, whereas those of the European penduline tits are relatively long. Perhaps the most constant family feature is the bill, which in most species is conical and sharply pointed.

Distribution

With the exception of the North American verdins (Auriparus flaviceps), the penduline tits are primarily an Old World family with a wide distribution from Africa through Europe and into Asia.

Habitat

Penduline tits are found in a range of habitats from the deserts of Arizona to the expansive reedbeds of the black-headed penduline tits (Remiz macronyx) and the sub-Saharan scrub and forests of the African penduline tits.

Behavior

Penduline tits are extremely active and agile birds. Typically, they are found in pairs or in small groups. Forest-dwelling species spend much time in the tree canopy, using their agility to move through branches, sometimes nimbly making their way along the undersides of twigs and boughs. Like long-tailed tits (Aegithalidae), they may roost in groups at night. Verdins are of particular interest in their construction of roosting nests. These are similar to breeding nests but lack soft linings and are generally less "finished."

Penduline tits from north temperate areas migrate outside the breeding season; other species are largely sedentary.

Calls are high pitched and songs range from the rich vocalizations of the Remiz to the rather more repetitious Anthoscopus. They are territorial in the breeding season, but the territory is largely confined to the immediate environs of the nest. This small, defended area leaves room for possible semicolonial nesting in species such as the European penduline tit.

Feeding ecology and diet

Penduline tits feed on a variety of invertebrates, fruit, and seeds. Like true tits, they are able to grasp food in one foot and peck at the item with their bill. Often they search for food, such as spider's nests, in crevices and holes in trees.

Reproductive biology

The mating system, where studied, has proven highly complex. European penduline tits can be monogamous, polygamous, and polyandrous. With the African penduline tit, the presence of unusually large clutches in single nests may be evidence of the attentions of more than one female.

In northern temperate species, breeding takes place from April through July. In Africa, breeding depends on local climatic conditions, with some species nesting in the rainy season and others in the dry season.

Penduline tits derive their family name from their free-hanging, pendulous nests. These are found in a variety of locations in the branches of trees and shrubs or, in the case of European penduline and black-headed tits, from groups of reeds.

They are teardrop or pear-like in shape with a convenient entrance hole towards the top. In some genera, such as the Anthoscopus, this entrance has a ledge sometimes visited by other birds. The entrance is fastened together when not in use as a defense against predators. In addition, when the en-trance is closed in this way the ledge gives the appearance of a confusing false entrance.

Nests are constructed from plant matter in most cases, compressed to produce a durable exterior and lined with softer grasses, mosses, and lichens inside for a snug home. The conspicuous nest of the verdin differs a little in construction in that the exterior is woven from hundreds to as many as 2,000 thorny twigs. The fire-capped tit is the only one without a pendulous nest, preferring an altogether more conservative cup-shaped structure hidden a tree hole.

Most penduline tit eggs are white. Clutch size varies from two to nine. Where observed, incubation takes between 13 and 17 days. Once the chicks hatch, care of the young is often shared between parents. In some species, care may be cooperative within a larger group (e.g. tit-hylia).

Conservation status

The European penduline tit considerably expanded its range westwards between the 1930s and the 1980s. Likewise, the Chinese penduline tit (Remiz consobrinus) has also increased in observed numbers on migration and on its wintering sites. Others, such as the white-crowned (Remiz coronatus) and black-headed tits, are not faring as well in face of the relentless intensification of agriculture and development of land. Some species though, especially the Anthoscopus, are described as uncommon but may simply be over-looked by observers.

Significance to humans

Admired as architects, they are otherwise of little significance to humans. However, the nests of European penduline tits have been used in Eastern Europe as slippers for children.

Species accounts

List of Species

European penduline tit
African penduline tit
Fire-capped tit
Verdin

European penduline tit

Remiz pendulinus

taxonomy

Remiz pendulinus Linnaeus, 1758. Four subspecies.

other common names

English: Eurasian penduline tit, penduline tit; French: Rémiz penduline; German: Beutelmeise; Spanish: Baloncito Común.

physical characteristics

4.3 in (110 mm); 0.28–0.44 oz (8–12.5 g). A small tit with, for the group, a relatively long tail. Nominate race: sexes similar, though female paler; prominent black face mask contrasting with otherwise gray head; chestnut brown back, pale buff beneath; juvenile lacks mask.

distribution

A Eurasian bird with a breeding range from western Europe to western Siberia and south to Turkey. Northern populations migratory, moving to southern Europe and the Middle East in winter.

habitat

Largely found in wetlands with a mix of reed and scrub, including willow and alder.

behavior

Gregarious in flocks of up to 60 birds, especially out of season and on migration. Males aggressively defend immediate territory around nest in breeding season, but this small area allows for possible semi-colonial nesting.

feeding ecology and diet

Feeds on invertebrates, including insects and spiders; reed seeds important in winter.

reproductive biology

Constructs pendulous (free hanging) pear-shaped nest from compressed plant material and lined with softer items. Suspended from branches or a number of reed stems. Clutch size is two to seven eggs; incubation 13–14 days; fledging 18–26 days.

conservation status

Not threatened. Locally common in suitable habitat. Considerable westward expansion between 1930s and 1980s.

significance to humans

None known.

African penduline tit

Anthoscopus caroli

taxonomy

Anthoscopus caroli Sharpe, 1871. Eleven subspecies.

other common names

English: Gray penduline tit; French: Rémiz de Carol; German: Weisstirn-Beutelmeise; Spanish: Baloncito Africano.

physical characteristics

3.5 in (90 mm); 0.21–0.24 oz (6–6.9 g). A variable but bland warbler-like species with a typical conical pointed bill and short tail. Upperparts range between species from olive-green to gray; underparts from pale yellow to cream.

distribution

Most widespread of the Anthoscopus spp. with a range from Kenya to South Africa.

habitat

Woodland.

behavior

Found in pairs or small groups, sometimes foraging in the tree canopy with other species. Very active.

feeding ecology and diet

Feeds on invertebrates and fruit.

reproductive biology

Breeds throughout the year across its wide range. Nest typical of the subfamily; pear shaped pendulous sack of compressed plant material provided with a entrance hole and ledge. The hole is fastened together when not in use. Clutch 4–6 white eggs, occasionally more possibly due to two females laying in the same nest. Incubation and fledging periods not known.

conservation status

Not threatened, but some contraction along coastal areas. May be overlooked.

significance to humans

None known.

Fire-capped tit

Cephalopyrus flammiceps

taxonomy

Cephalopyrus flammiceps Burton, 1836. Two subspecies.

other common names

French: Rémiz tête-de-feu; German: Flammenstirnchen; Spanish: Baloncito de Capa en Llamas.

physical characteristics

4 in (100 mm); 0.25 oz (7 g). A small short-tailed tit. Sexes similar out of breeding season, olive-green above and olive-yellow below. Breeding male has distinctive orange red forecrown (the "fire cap"), chin, and throat. Juveniles dull, but similar to adults.

distribution

Himalayas and parts of Western China. Northern India and northern parts of southeast Asia outside breeding season.

habitat

Moist, temperate woodland and forest.

behavior

Active and agile bird that forages in single species or mixed flocks in the tree canopy.

feeding ecology and diet

Invertebrates plus flower and leaf buds.

reproductive biology

Nests April to June in holes in trees. Clutch of three to five blue-green eggs; incubation and fledging periods not known.

conservation status

Not threatened. Scarce over much of its breeding and wintering range.

significance to humans

None known

Verdin

Auriparus flaviceps

taxonomy

Auriparus flaviceps Sundevall, 1850. Six subspecies.

other common names

French: Auripare verdin; German: Goldköpfchen; Spanish: Baloncito Verdín.

physical characteristics

4–4.5 in (100–110 mm); 0.21–0.29 oz (6–8.2 g). Small with sharper bill than its relatives. Dull yellow head and throat, dark grey upperparts, lighter grey beneath.

distribution

Southwestern United States and Mexico.

habitat

Open desert with scattered bushes and cacti.

behavior

Sprightly birds normally found in pairs and family groups. More solitary than other penduline tits. Interesting in its construction of roosting nests.

feeding ecology and diet

Feeds on invertebrates, seeds, and fruit.

reproductive biology

Breeds from March to June. Nest a spherical construction up to 7.9 in (200 mm) diameter of layered thorny and thornless

twigs lined with softer material and located in scrub towards the end of branches. Clutch of two to four blue-green eggs; incubation 14–17 days; fledging 17–19 days.