|Scientific Name:||Archaius tigris|
|Species Authority:||(Kuhl, 1820)|
Calumma tigris (Kuhl, 1820)
Chamaeleo tigris Kuhl, 1820
|Taxonomic Notes:||This species was transferred to the genus Calumma by Klaver and Böhme (1986) and then back to Archaius by Townsend et al. (2010). The species is found on three oceanic islands that are separated by 20-50 km of open water. It is expected that migration between islands is extremely infrequent, and that populations are divergent, possibly at the species level. These populations therefore, should be investigated in a phylogenetic framework.|
|Red List Category & Criteria:||Endangered B1ab(ii,iii)+2ab(ii,iii) ver 3.1|
|Assessor(s):||Gerlach, J. & Ineich, I.|
|Contributor(s):||Anderson, C.V. & Tolley, K.|
This species is listed as Endangered, because its extent of occurrence is 1,190 km² and its area of occupancy is 45 km², and it is found in three threat locations associated with the spread of invasive cinnamon which is altering ecological function across the landscape. Overall, there is a decline in the extent and quality of its forest habitat, especially on Mahé and Praslin islands, due transformation of habitat by invasive species and for human activities.
This species is endemic to the Seychelles islands of Mahé, Silhouette, Praslin. A historical record from Zanzibar (Tanzania) is erroneous. It occurs from sea level to 550 m asl, in areas of the islands that have either primary or secondary forest, or in the transformed landscape if there are trees and bushes present. Although they are currently estimated to have a restricted distribution on each island (following survey transects conducted by Gerlach 2008a), if anecdotal observations from transformed landscapes (e.g. degraded areas outside the areas surveyed) are valid, then the distribution would be larger than mapped at present.
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||This species is often cited as occurring at "comparatively" low density (e.g. Pawlowski and Krämer 2012), but a quantitative study suggests that Archaius tigris densities (2.07 ±5.00 per hectare) in areas unaffected by the spread of invasive cinnamon trees (Cinnamomum verum) are similar to that of some other chameleon species (Gerlach 2008a). There is a negative correlation between chameleon density and the presence of cinnamon (Gerlach 2008a), suggesting this invasion is detrimental to chameleon populations.|
|Habitat and Ecology:||Archaius tigris is an arboreal species in found in tropical forest, particularly in forest valley habitats (Gerlach 2008a) but it tolerates altered environments. It can be found in roadside vegetation, rural gardens and secondary forest (Bringsø 2007). It has also been recorded in coconut plantation, eroded hillside scrub, and primary palm forest (Gardner 1986). Although most observations of reproduction show that the chameleon will dig a hole in the ground to lay eggs (e.g. Gerlach and Gerlach 2002), its reproduction on Mahé is associated with introduced pineapple (Ananas comosus), as it occasionally lays eggs inside the leaf axils (Van Heygen and Van Heygen unpubl. data). Although this strategy has not been observed on Silhouette or Praslin islands, Van Heygen and Van Heygen (unpubl. data) report an ad hoc experiment conducted with one female from Silhouette which, when given the choice between a bromeliad leaf axil and soil, chose the leaf axil to lay her clutch. If this species' natural nesting sites are typically leaf axils, the native host species are not known but are assumed to be the endemic Pandanus and palms (Lodoicea maldivica). Archaius tigris has been reported as occurring in higher densities closer to rivers by some workers (e.g. Gerlach 2008a), where others found no association between proximity to rivers and chameleon occurrence (e.g. Bringsø 2007).|
|Use and Trade:||
No annual CITES export quotas for Archaius tigris have been issued between 2000 and 2014 (CITES 2014). Between 1977 and 2013 a total of 12 live individuals were exported from the Seychelles for the pet trade (total of all personal and commercial exports), of which 2 were exported to Germany in 1981 and 10 to Spain in 1993 (UNEP-WCMC 2014). An additional 98 dead specimens were exported between 1981 and 2010 for scientific or zoological purposes, along with a single live specimen in 1982 for scientific purposes (UNEP-WCMC 2014). No other trade is reported out of the Seychelles, although re-export of specimens imported to Germany and Spain has been reported to Switzerland and South Africa, respectively (UNEP-WCMC 2014). This species is present and available in limited quantities in the European pet trade (C. Anderson pers. obs. 2014), and illegal trade and/or harvest may occur on a limited basis.
|Major Threat(s):||The main threat is habitat degradation as a result of the invasion by alien plants species, especially Cinnamomum verum, principally on Mahé and Praslin. Cinnamon is displacing other vegetation, it is present all over the islands and it is the fastest growing, heaviest seeding plant in most areas (Fleishmann 1999) and is changing the composition of the forests. Currently it makes up 70-90% of trees in Seychelles forests (Kueffer et al. 2010), reaching >95% in some areas. For Archaius tigris, the cinnamon trees provide a normal structure of vegetation, but the invaded forests support a massively diminished insect population (Gerlach 2008b), somewhere in the region of 1% of normal abundance. This excludes invasive ants which are the only common invertebrates associated with cinnamon. In addition, the cinnamon produces a denser canopy than native trees, giving deeper shade which excludes forest floor undergrowth (other than cinnamon seedlings), and this also is a factor in the reduced insect abundance. The chameleons are found on cinnamon and in cinnamon invaded areas, as long as there is a wide diversity of other plants and a dense undergrowth. In fact, rural gardens can provide habitat for the chameleons, because these tend to be more diversity in terms of flora, and therefore can support invertebrate fauna.|
|Conservation Actions:||Archaius tigris is present in the Morne Seychelles, Praslin and Silhouette National Parks. Although much of the forested area occupied by chameleons is protected, these protected areas are not effectively managed with the exception of the Vallee de Mai on Praslin. Attention to the invasion of cinnamon is needed, in order to ensure that there is suitable habitat for this species.|
|Citation:||Gerlach, J. & Ineich, I. 2014. Archaius tigris. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 31 January 2015.|
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