Alethe choloensis

Geographic Range

Alethe choloensis populations are found in disjunct forest fragments in southeastern Malawi and nearby Mozambique. They are known from approximately 16 forest fragments: 13 in Malawi and 3 in Mozambique.

• Biogeographic Regions
• ethiopian ethiopian
  • native native

Habitat

Cholo alethes are found in mid-altitude montane evergreen forests and in lower elevation habitats during the non-breeding season. An important habitat feature for these birds is the presence of ant nests, which are critical for their foraging habits. When ant nests are present, breeding pairs can persist in forest fragments as small as 0.5 hectares.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Terrestrial Biomes
• forest forest
• mountains mountains

Physical Description

Cholo alethes have warm brown plumage that is a deep, rich tone on the back and becomes pale and grayish on their ventral surfaces. The chin and throat are white and the outer tail feathers are white. The plumage is grayish on the sides of the face and neck. They have long, pink or flesh-colored legs and toes and are approximately 16 cm in total length. They are thrush-like in general appearance. No sexual dimorphism is described.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes alike

Reproduction

No information on mating systems in cholo alethes have been reported. The literature does suggest that cholo alethes pair for mating, suggesting monogamy.

Cholo alethes seem to breed from September to January. Only 1 nest has been documented, it was placed in the fork of a tree 4 m above the ground. Other information on reproduction in this species is not reported in the literature.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

No information on parental investment is reported in the literature. If pairs form for breeding, it can be assumed that male and female parents contribute to the protection and feeding of their young. Most young in the family Turdidae are altricial.

• Parental Investment
• altricial altricial
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female

Lifespan/Longevity

There is no information on longevity in cholo alethes. Related birds of similar sizes can live up to 14 years in the wild.

Behavior

Observations suggest that cholo alethes forage on or near the forest floor among swarms of red ants. They may undergo small elevational migrations between higher elevation forests during the breeding season and lower elevation forests during the non-breeding season.

• Key Behaviors
• arboreal arboreal
• flies
• diurnal diurnal
• motile motile
• migratory migratory
• sedentary sedentary

Home Range

Home range sizes are not reported in cholo alethes.

Communication and Perception

Cholo alethes have melodic songs and a soft alarm called described as a "trrrp."

• Communication Channels
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Cholo alethes feed among ant swarms, catching the small arthropods that flee the oncoming mass of ants. It has also been suggested that they may consume ants that crawl onto their bodies when they are foraging near and within the swarm. They hop into swarms from logs or low branches and then quickly fly away again - at which point they make beak-clicking noises and flap their wings.

• Primary Diet
• carnivore carnivore
  • insectivore insectivore
  • eats non-insect arthropods

• Animal Foods
• insects
• terrestrial non-insect arthropods

Predation

Predators on cholo alethes are not reported in the literature.

Ecosystem Roles

Cholo alethes have an important symbiotic relationship with ants, following ant swarms to take advantage of fleeing arthropods. They occupy a niche similar to the antbirds of the neotropics ( Thamnophilidae ).

Economic Importance for Humans: Positive

Cholo alethes are rare birds that may attract some ecotourism interest. They are important members of native ecosystems, exploiting a niche similar to the neotropical antbirds .

Economic Importance for Humans: Negative

There are no adverse effects of Alethe choloensis on humans.

Conservation Status

Cholo alethes are considered endangered by the IUCN red list. They are endemic to a very small range, fragmented populations, and high levels of habitat destruction via deforestation. Concerns about the rates of deforestation increasing in their range, caused some researchers to call for a new listing as critically endangered in the near future. Two populations were recently discovered in approximately 1600 hectares of montane forest on Mt. Chiperone and approximately 5000 hectares of evergreen forest on Mt. Mabu, both in Mozambique. These population increase estimated global population sizes. At least for the time being, those populations are not currently threatened with high levels of deforestation. It is likely that populations of cholo alethes have been shrinking with the reduction and fragmentation of tropical montane forests in Africa, as the extent of these forests has continued to shrink since the last glacial maxima, approximately 20,000 years ago. Humans have greatly hastened this habitat fragmentation and reduction in recent years.

Some of the forest fragments occupied by cholo alethes are protected as forest reserves, although enforcement of land protection in these areas is often poor. An effort to protect Mulanje Mountain, in Malawi, will help to protect a substantial population of these birds. Efforts are underway to protect areas in Mozambique where cholo alethes are found. Current population estimates range from 2,500 to 10,000 individuals.

Other Comments

Beresford (2003) suggested a new genus for the cholo alethes and close relatives: Pseudoalethe based on mitochondrial and nuclear DNA sequence data. Based on those data the genus Alethe was polyphyletic, calling for the separation of Alethe castanea and Alethe diademata from other species of Alethe : Alethe poliocephala , Alethe fuelleborni , Alethe choloensis , and Alethe poliophrys . Currently, however, the Howard and Moore Checklist of Bird Species of the World (2003) only recognizes 5 species and retains them in the genus Alethe : Alethe diademata , Alethe poliophrys , Alethe poliocephala , Alethe fuelleborni , and Alethe choloensis . Alethe castanea is recognized as a subspecies: A. diademata castanea . Beresford (2003) suggested sister-species relationship between A. choloensis and A. fuelleborni .

Alethe choloensis is also known by the common names: Thyolo alethe and Cholo Mountain alethe.

Additional Links

Encyclopedia of Life

Contributors

Tanya Dewey (author), Animal Diversity Web.

References

Barnes, K., F. Dowsett-Lemaire, M. Dyer, J. Haugaard, P. Kaliba, L. Luhanga, V. Parker. 2009. "Species factsheet: Thyolo alethe ( Alethe choloensis )" (On-line). BirdLife International. Accessed February 11, 2009 at http://www.birdlife.org/datazone/search/species_search.html?action=SpcHTMDetails.asp&sid=6456&m=0 .

Beresford, P. 2003. Molecular systematics of Alethe, Sheppardia and some other African robins (Muscicapoidea). Ostrich , 74: 58-73.

BirdLife International, 2008. " Alethe choloensis " (On-line). IUCN Redlist of Endangered Species. Accessed February 10, 2009 at http://www.iucnredlist.org/details/147307 .

Dickinson, E. 2003. The Howard and Moore Complete Checklist of the Birds of the World . Princeton: Princeton University Press.

Marshall Cavendish Corporation, 2001. Endangered Wildlife and Plants of the World . New York: Marshall Cavendish.

Seddon, N., J. Ekstrom, D. Capper, I. Isherwood, R. Muna, R. Pople, E. Tarimo, J. Timothy. 1999. The importance of the Nilo and Nguu North Forest Reserves for the conservation of montane forest birds in Tanzania. Biological Conservation , 87: 59-72.

Spottiswoode, C., I. Patel, E. Herrman, J. Timberlake, J. Bayliss. 2008. Threatened bird species on two little-known mountains (Chiperone and Mabu) in northern Mozambique. Ostrich , 79: 1-7.