The São Tomé grosbeak (''Crithagra concolor'') is the largest member of the canary genus ''

Crithagra ''Crithagra'' is a genus of small passerine birds in the finch family (Fringillidae). They live in Africa and Arabia. The species in this genus were formerly assigned to the genus '' Serinus'', but phylogenetic analysis of mitochondrial and nucl ...

'', 50% heavier than the next largest canary species, and possesses a massive bill for a member of that genus. It is endemic to the island of

São Tomé São Tomé is the capital and largest city of the Central African island country of São Tomé and Príncipe. Its name is Portuguese for " Saint Thomas". Founded in the 15th century, it is one of Africa's oldest colonial cities. History Álv ...

. For a long period this bird was known only from three nineteenth-century specimens. It was rediscovered in 1991. The current population is estimated at less than 250, and it is classified as critically endangered by the IUCN. The main threat is

habitat destruction Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

. The São Tomé grosbeak was formerly placed in the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Neospiza'' (meaning "new

finch The true finches are small to medium-sized passerine birds in the family Fringillidae. Finches generally have stout conical bills adapted for eating seeds and nuts and often have colourful plumage. They occupy a great range of habitats where the ...

") but was assigned to the genus ''

'' based on a phylogenetic analysis of

mitochondrial A mitochondrion () is an organelle found in the cells of most eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used ...

and nuclear DNA sequences.

Habitat

The Sao Tome Grosbeak was initially believed to inhabit only lowland native forests. Recent observations expanded its known habitat range, with sightings in secondary forests at higher elevations. This canopy-dwelling bird is quite silent and unresponsive to playback, making it challenging to detect. However, it becomes more observable during the short dry season when many birds are breeding. The Sao Tome Grosbeak often moves in pairs or alone and descends to the forest understorey to feed on seeds using its powerful bill. Understanding its habitat and behavior is crucial for its conservation on Sao Tome.

Threats

Historical Deforestation and Habitat Changes

Historically, extensive lowland forest areas were cleared to establish cocoa plantations. Subsequent abandonment of these plantations led to the development of secondary forests, which are less suitable for the Sao Tome Grosbeak. Additionally, the introduction of an oil palm plantation further exacerbated habitat loss.

Predators and Impact

The presence of introduced species like the Black Rat (Rattus rattus), Mona Monkey (Cercopithecus mona), African Civet (Civettictis civetta), and feral cats (Felis catus) raises concerns about potential predators of the Sao Tome Grosbeak. However, further research is needed to assess their actual impact on the bird's population.

References

External links

BirdLife Species Factsheet
Crithagra Endemic birds of São Tomé and Príncipe Endemic fauna of São Tomé Island Grosbeaks Critically endangered fauna of Africa Birds described in 1888 {{Fringillidae-stub