Slender pigeon lice are host specific, being found on only four species of pigeons. The species of pigeons on which these lice are found are pale-backed pigeons, speckled pigeons, rock pigeons, and stock pigeons. The distribution of slender pigeon lice depends largely on the distribution of their hosts. Rock pigeons in particular have a wide geographic range that includes every continent of the world excluding Antarctica. Slender pigeon lice therefore may be found in any of these regions. Collectively, the hosts of slender pigeon lice are native to Europe, Africa, and parts of Asia, however pigeons have spread by human introduction to their current global distribution. Slender pigeon lice have followed their hosts, and are also considered introduced wherever pigeons are non-natives. (Ash, 1960; Keirans, 1975; Nelson and Murray, 1971)
Slender pigeon lice are primarily found in the feathers on the undersides and upper wings of pigeons. This is typical of flat-bodied lice such as Columbicola columbae, as opposed to rounder species that are traditionally found in other areas of a host, such as the head. For this reason, Columbicola columbae is rarely found on the bodies of pigeons.
Geographical habitats include any region a host pigeon would inhabit. Depending on the species of pigeon, hosts and their associated lice inhabit grasslands, shrublands, and deserts, as well as agricultural, urban and suburban areas. (Adams, et al., 2005; Ash, 1960)
Columbicola columbae resembles a typical louse, being wingless and dorso-ventrally flattened with eyes that are not well-developed (vestiges of eyes). However, it is long and slender with a more flattened appearance than many other louse species. Characteristic of this species is the presence of two blade-like hairs (setae) and thin antennae with five segments on the anterior portion of its head. They can normally grow to be from 2 to 3 mmm long and are black or brown in color. As a member of the suborder Ischnocera, Columbicola columbae also has an extension (known as the cylpeus) on the front or anterior portion of its head, which comes into contact with the hair or feathers of the host when the lice are feeding or at rest. This species exhibits no sexual dimorphism. (Ash, 1960; Nelson and Murray, 1971)
Columbicola columbae demonstrates hemimetabolous development, or gradual metamorphosis, which is characteristic of all Phthiraptera. Immature lice are termed nymphs, and Columbicola columbae, like all lice, proceeds through three nymphal instars, or stages between molts, to reach their final adult stage. As all species of lice are permanent ectoparasites of their hosts, slender pigeon lice have no free-living stages and would not live long if removed from their hosts. (Schmidt and Roberts, 2009)
Little is known regarding specific mating systems of Columbicola columbae. Currently, this species is regarded as polygynandrous, and showing no mate fidelity. How these lice locate, select, or defend mates is poorly understood. (Schmidt and Roberts, 2009)
As permanent ectoparasites of their hosts, Columbicola columbae males and females mate on the host. This species exhibits a reversed mating position where the female is on top of the male with the male holding the female above him with his antennae. Males transfer sperm to females through an organ termed the aedeagus, which is located toward the back of the abdomen.
Female Columbicola columbae deposit and attach their eggs to the feathers on the underside of the host’s wing, usually trying to do so close to the pigeon’s body. This is presumably to provide warmth and a safer environment for the eggs. The eggs can typically be expected to hatch within 3 to 5 days if exposed to a steady temperature of around 98.6 degrees Fahrenheit (37 degrees Celsius). Females can potentially lay up to 9 eggs per day. Individuals of this species are sexually mature as soon as they reach the adult phase. (Martin, 1934; Saif, 2003)
Little parental investment is involved in this species. Females lay eggs close to the bodies of pigeons, presumably in an effort to provide warmth and protection to the eggs. (Martin, 1934)
In order to evade the preening behaviors of their pigeon hosts, Columbicola columbae move between the feather barbs, using their legs and mandibles to attach themselves to the barbs. These lice are able to move between the feather barbs quite easily due to their slender, flattened body shape. Columbicola columbae do not have the capacity to disperse on their own, and therefore must rely on other organisms to transfer them to new hosts if needed. Physical contact between two pigeons is one method of transfer. The second method of transfer involves a hippoboscid pigeon fly pseudolynchia canariensis. Columbicola columbae will climb onto the highly motile fly to transfer from one host to another. However, this is risky for the lice as the flies aren't completely obligate to pigeons, which may result in the transfer of lice to an unsuitable host, and subsequent death. (Ash, 1960; Saif, 2003)
Home range size for Columbicola columbae is unknown, however most lice hatch, live, and die while on one host pigeon.
This species has no significant forms of communication, but perceives its environment mainly through visual means by way of vestigial eyes, and arguably through tactile means.
Columbicola columbae feeds by chewing on the feathers of their pigeon hosts, particularly feeding on the downy part of the wing feathers. However, these lice also have the ability to move from the wings to the body to feed on the fluff of the basal parts of the feathers found there. The body structure known as a clypeus comes into contact with the feathers of the pigeon host when feeding. Columbicola columbae does not feed on blood. (Martin, 1934; Saif, 2003)
This species has no known predators, although any predators of its pigeon hosts could be problematic for the resident lice.
Columbicola columbae is a louse that parasitizes four species of pigeons, pale-backed pigeons, speckled pigeons, rock pigeons, and stock pigeons. This species feeds on the feathers, but are not fatal to nor cause significant damage to their hosts. They are not known to vector or cause any diseases. Therefore, they do not cause any great losses in pigeon populations. This species has a bacterial endosymbiont in its gut belonging to the class Proteobacteria (gamma subdivision of the class) and may be a result of its feather diet. (Ash, 1960; Fukatsu, et al., 2007; Nelson and Murray, 1971)
Columbicola columbae is among the species of chewing lice frequently used by biologists and researchers looking to research the biology of interactions between parasites and their hosts, and possibly how these interactions change over time as the hosts and parasites co-evolve. In fact, such experiments with lice like Columbicola columbae have revealed a relatively strong correlation between the host specificity of a louse and its host’s body size. Experiments in which lice were transferred to hosts smaller than their normal hosts showed that the lice did not typically survive unless the host’s efficiency at grooming was somehow hindered. In the reverse situation in which lice were transferred to hosts larger than their own, they did not survive regardless of the hindering of the host’s grooming capabilities. This is significant because it leads one to hypothesize that lice are most likely to switch to a host whose body size resembles their own host’s body size. Therefore, lice such as Columbicola columbae can shed light on important aspects of the relationships between parasites and hosts, which humans can use for their advantage and possibly eradication. (Bush and Clayton, 2006; Schmidt and Roberts, 2009)
Columbicola columbae do not parasitize humans, and their pigeon hosts are not a significant food source for humans so they have virtually no negative impact on humans. Additionally, they are not known to vector or cause any diseases that could possibly infect humans.
Presently, Columbicola columbae is not threatened or at risk of becoming endangered. Due to its reliance on host species, fluctuations in host populations can have a dramatic effect on populations of Columbicola columbae. Columba eversmanni is experiencing significant population declines of unknown origin. Hypothesized causes include overhunting, deforestation, or agriculture. As this species of pigeon becomes more scarce, the populations of the obligate parasitic lice feeding on them will inevitably suffer losses as well. Other populations of Columbicola columbae do not seem to be in any danger of decline, as rock pigeons Columba livia are one of the most widely distributed birds. (Adams, et al., 2005; Ash, 1960)
Andrea Kummer (author), University of Michigan-Ann Arbor, Heidi Liere (editor), University of Michigan-Ann Arbor, John Marino (editor), University of Michigan-Ann Arbor, Barry OConnor (editor), University of Michigan-Ann Arbor, Rachelle Sterling (editor), Special Projects.
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
living in the southern part of the New World. In other words, Central and South America.
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
living in landscapes dominated by human agriculture.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
having a worldwide distribution. Found on all continents (except maybe Antarctica) and in all biogeographic provinces; or in all the major oceans (Atlantic, Indian, and Pacific.
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
union of egg and spermatozoan
fertilization takes place within the female's body
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
found in the oriental region of the world. In other words, India and southeast Asia.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
an organism that obtains nutrients from other organisms in a harmful way that doesn't cause immediate death
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
living in residential areas on the outskirts of large cities or towns.
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
living in cities and large towns, landscapes dominated by human structures and activity.
uses sight to communicate
breeding takes place throughout the year
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Bush, S., D. Clayton. 2006. Ecomorphology of parasite attachment: Experiments with feather lice. Journal of Parasitology, 1: 25-31.
Bush, S., D. Clayton. 2006. The role of body size in host specificity: Reciprocal transfer experiments with feather lice. Evolution, 10: 2158-2167.
Fukatsu, T., R. Koga, W. Smith, K. Tanaka, N. Nikoh, K. Sasaki-Fukatsu. 2007. Bacterial Endosymbiont of the Slender Pigeon Louse, Columbicola columbae, Allied to Endosymbionts of Grain Weevils and Tsetse Flies. Applied and Environmental Microbiology, 73: 6660-6668.
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Saif, Y. 2003. Diseases of Poultry. Wiley-Blackwell.
Schmidt, G., L. Roberts. 2009. Foundations of Parasitology. New York, NY: McGraw-Hill.