Old World Passerines (Leiothrichidae)
ORDER
The taxonomic order PASSERIFORMES (pronounced pas-ser-i-FOR-meez) is comprised of one hundred eighteen families of perching birds, including warblers, vireos, sparrows, tits, and laughingthrushes.
FAMILY TAXONOMY
The Leiothrichidae (pronounced LAY-oh-thrick-a-day) is a large and diverse family of Old World passerines that inhabit tropical areas, primarily India and Asia. It contains sixteen genera divided into one hundred thirty five species of laughingthrushes, cutias, barwings, crocias, sibias, babblers, liocichlas, minlas, babaxes, and leothrix. While Leiothrichidae is not technically a new family, this particular use of the name is new as of 2019. DNA analysis led the AOS to move the Leiothrichidae out from their previous classification as Old World Babblers (Timalliidae).
NORTH AMERICA
Leiothrichidae are not native to North America but three species, Greater Necklaced Laughingthrush, Hwamei, and Red-billed Leiothrix, were introduced to Hawaii in the late 19th and early 20th centuries.
KNOWN FOR
Laughingthrushes are known for their garrulous nature which gave rise to the name of the Garrulax genus and babbler common names. Most species are skulking residents of thick forests, so they are usually heard and seldom seen.
PHYSICAL
The laughingthrush family includes small and medium-sized songbirds. The only common feature is an all-purpose bill shape. Some members of this family are bulky ground-dwelling birds that call to mind Towhees and Thrashers; others are delicate and petite like Wrens or Chickadees.
COLORATION
Many species in this family are nondescript with gray or brown plumage, but many others have striking plumage colors and patterns. The three species in North America exemplify this dichotomy: the Greater Necklaced Laughingthrush and Hwamei are rather plain while the Red-billed Leothrix has yellow and red contrasting sharply with black and brown. Generally speaking, Leiothrichidae are not sexually dimorphic, meaning that males and females look the same, and there are usually only minor differences between immature and adult plumages.
GEOGRAPHIC HABITAT
For the most part, laughingthrushes are found in tropical areas, with the greatest concentration in India and Asia. Many species are forest residents but some live in scrubland, savannas, or marshes. They can be found from elevations near sea-level to well over 10,000 feet.
MIGRATION
Leiothrichidae are generally not migratory. Some species disperse short distances from their breeding grounds. The few species that undertake true migrations are altitudinal migrants, meaning they move from higher elevations to lower elevations during the year. The three species in North America do not migrate.
HABITS
Like everything else about this family, it is difficult to make sweeping statements about their habits. They run the social gamut from territorial loners to gregarious colony dwellers. Diets tend to be omnivorous with insects and other arthropods being main food items.
CONSERVATION
Around 75% of the laughingthrush family is considered to be Least Concern or Not Globally Threatened. Restricted ranges, habitat loss, and/or trapping for the pet trade are the reasons some species are in the Vulnerable, Endangered, or Critically Endangered categories.
INTERESTING FACTS
The Leiothrichidae family was once considered a part of the “waste basket” family Timaliidae, so described because its 400+ members were very different physically and ecologically. Noted naturalist William Swainson coined family name in 1832. The Red-billed Leiothrix and Hwamei are popular caged birds and it has long been speculated that escapees played a role in establishing the populations in Hawaii; the introduction of the Greater Necklaced Laughingthrush is less clear.