The thick-billed siskin (Spinus crassirostris) belongs to the family of true finches and siskins, the Fringillidae.
The thick-billed siskin is distributed in South America (Peru, Bolivia, Chile and Argentina). The siskin species occurs locally in the Andes Mountains. This siskin is polytypic species.
Appearance, physical description and identification
The thick-billed siskin (Spinus crassirostris) is a medium-sized siskin, measuring 12 to 14 cm in length and weighing 20 grams.The thick-billed siskin has overall greyish-olive plumage. The mature male has a black head, upper nape, chin and throat. The female is duller and lacks the black head. The vent region is whitish in both sexes.
The bill is large and stout with silvery base. The irises are blackish. The legs and feet are dark gray. Their call is a prolonged, twittering "klee-ee" or "cheh-cheht" sound.
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| 1.Birds of South America - Image of female Thick-billed siskin - Spinus crassirostris by Pablo Caceres Contreras |
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| 2.Birds of South America - Image of female Thick-billed siskin - Spinus crassirostris by Pablo Caceres Contreras |
Origin, geographical range and distribution
The thick-billed siskin species are distributed in the Andes Mountains in South America. They are distributed in Peru, Bolivia, Chile and Argentina.The thick-billed siskin nominate subspecies S. c. crassirostris is distributed in Andes mountains in southern Bolivia, northwest Argentina and central Chile.
The subspecies S. c. amadoni has patchy distribution. It is distributed in the Andes mountains in the central Peru. It is also distributed in southeast Peru, extreme north Chile and northwest Bolivia.
Ecosystem and habitat
The thick-billed siskin species have low forest dependence. They normally occur in altitudes between 3000 to 4000 meters.The natural ecosystems and habitats of these siskin species include tropical and subtropical high altitude grasslands, Polylepis woodlands, high altitude shrublands, montane Andean steppes and moist montane forests.
Diet and feeding behavior
The diet of this thick-billed siskin species consists mainly of plant matter. Polylepis seeds, buds and shoots are their primary food. They feed on the ground as well as in shrubs.Reproduction and breeding habits
The breeding season of these siskin species appears to be in March and April. There no further information on their reproduction and breeding habits.Migration and movement patterns
These thick-billed siskin species are resident as well as nomadic and partial migrant birds. The populations in higher altitudes move to lower levels in winter. Some populations move northwards within their range during winter.Thick-billed siskin - Quick Facts
- Scientific name: Spinus crassirostris
- Species author: (Landbeck, 1877)
- Synonyms/Protonym: Chrysomitris crassirostris Landbeck, 1877
- Family: Fringillidae › Passeriformes › Aves › Chordata › Animalia
- Vernacular names: English: Thick-billed siskin, Chinese: 厚嘴金翅雀, French: Tarin à bec épais, German: Dickschnabelzeisig, Spanish: Jilguero piquigrueso, Russian: Толстоклювый щегол, Japanese: ハシブトヒワ
- Other names: Thick-billed Siskin
- Distribution: South America
- Diet and feeding habits: seeds, buds, shoots
- IUCN status listing: Least Concern (LC)
Conservation and survival
The global population size of the thick-billed siskin (Spinus crassirostris) has not been quantified. The overall population trend of the species is considered to be stable.In most of its range, this siskin species is reported to be uncommon and patchily distributed (Stotz et al. 1996). The generation length is 4.2 years. Its distribution size is about 1,750,000 sq.km.
Habitat alteration, human disturbance and capture for pet-trade are the main threats that are endangering the survival of this siskin species.
IUCN and CITES status
The thick-billed siskin (Spinus crassirostris) does not approach the thresholds for being Vulnerable either under the range size criterion, or under the population trend criterion or under the population size criterion.The IUCN (International Union for Conservation of Nature) has categorized and evaluated the siskin species and has listed it as of "Least Concern".
The CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) status is ‘Not Evaluated’ for the thick-billed siskin (Spinus crassirostris).
| Taxonomy and scientific classification of Spinus crassirostris | |
|---|---|
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Family: | Fringillidae |
| Subfamily: | - |
| Genus: | Spinus |
| Species: | S. crassirostris |
| Binomial name: | Spinus crassirostris |
| IUCN status listing: |
 Least Concern |
S. c. crassirostris (Landbeck, 1877) and
S. c. amadoni George, 1964.
Thick-billed siskin image source: https://www.flickr.com/photos/pablocaceres/6495705775/
Image author: Pablo Caceres Contreras | License: CC BY-NC-ND 2.0 as on 8/1/18
Image source: https://www.flickr.com/photos/pablocaceres/6495704587/
Image author: Pablo Caceres Contreras | License: CC BY-NC-ND 2.0 as on 8/1/18
Current topic in Birds of South America: Thick-billed siskin - Spinus crassirostris.
