IUCN Red List Category: LC (Published 2013-08-26)
2013-08-26 00:00:00 UTC
Animalia | Chordata | Vertebrata | Reptilia | Squamata | Sauria | Chamaeleonidae | Chamaeleo | Chamaeleo dilepis |
Taxonomic notes: The taxonomy of Chamaelo dilepis, which may instead be a species complex, is uncertain and problematic (Largen and Spawls 2006). Pending resolution of this situation, Chamaeleo quilensis from Central and East Africa are here treated as "sporadic variants of Ch. dilepis" following Tilbury (2010). The name Chamaeleo ruspolii has historically been applied to a morphologically uniform population from Somalia and northern Ethiopia, however broader geographical sampling within the range of C. dilepis indicates that C. ruspolii is likely to fall within the range of natural variation in C. dilepis, and moreover that it appears to represent the northern end of a spectrum of intergradation, with southern Ethiopian populations exhibiting characters intermediate between "C. ruspolii" to the north and East African C. dilepis (Largen and Spawls 2006).
Although some authors still recognise the form C. d. quilensis as well as subspecies (C.d. roperi Boulenger 1890, C. d. idjwiensis Loveridge, 1942, C. d. isabellinus Günther 1893, C. d. martensi Mertens, 1964 and C. d. petersi Gray, 1865), these should be treated with extreme caution pending a full taxonomic review of this species. Considerable confusion in identifications as well as complete overlap for sub-species records exist. Recognition of these sub-species at this time over-inflates the taxonomic quotient and unnecessarily complicates the situation (Tilbury 2010).
This species is widely distributed throughout southern and eastern Africa. It has been described as ranging from as far west as Cameroon (Welch 1982), east to Kenya, southern Ethiopia and Somalia, and south through Equatorial Guinea, Gabon, Tanzania, the Democratic Republic of Congo, Angola into Botswana, Namibia, Malawi, Mozambique and South Africa (Tilbury 2010). Possible records of this species from West Africa (as C. quilensis) may be referable to the recently-described C. necasi (J-F. Trape pers. comm. 2012). There are limited records of the species occurring in Rwanda and Burundi (Spawls et al. 2002), however, this could be attributed to low recorder effort rather than genuine scarcity of the species in the area. The species has recently been confirmed on Lolui island in Uganda (S. Spawls pers. comm. 2010).
It occurs through most of southern Somalia, and in the Toghdeer region of the north as well as adjacent Ogaden in Ethiopia (Lanza 1990). There is a record of this species from Djibouti (Schätti 1989), but this author did not specify the basis for this (Ineich 2001) and its occurrence in this country is consequently in need of confirmation.
This species inhabits coastal forest, both moist and dry savannah, woodland and bushy grasslands, it has also been found in rural and suburban areas (Patterson 1987, Spawls et al. 2002, Largen and Spawls 2010, Tolley and Burger 2007). The species is arboreal, however it can often be observed crossing the ground (Tilbury 2010). The bulk of the diet consists of grasshoppers, beetles and other edible invertebrates; large individuals may eat vertebrate prey, such as geckos and other chameleons (Tilbury 2010). This species is commonly preyed upon by the boomslang (Dispholidus typus) and the twig snake (Thelotornis kirtlandi; Tilbury 2010) as well as a variety of birds and mammals. In southern Africa, mating usually takes place in November/December and gestation lasts about four months (Tilbury 2010). Females lay between 10-40 oval eggs, which take about 10-12 months to hatch (Tilbury 2010). Growth is rapid and sexual maturity is reached within one year of hatching (Tilbury 2010).
Although this species appears to be abundant locally, there is no quantitative information on population abundances or trends, and no population studies have been conducted. It is widespread and somewhat adaptable and as such is probably not undergoing any population declines at present.
Annual CITES export quotas for C. dilepis between 2000 and 2013 ranged from 4,000-16,000 (12,000 average) wild -collected individuals and 100-953 (272 average) captive bred, captive born, or ranched individuals per year across the native range (CITES 2013). Between 1977 and 2011 (2012 and 2013 trade data are incomplete or unavailable) a total of 111,734 live individuals were exported from across the native range of this species for the pet trade (total of all undeclared, captive breeding, personal and commercial exports), of which 1,010 were reported as either captive bred, captive born, or ranched (UNEP-WCMC 2013). All 1,010 individuals exported during this period as either captive bred, captive born, or ranched were exported from 1999 to 2008, with a peak of 381 individuals exported in 2001 (UNEP-WCMC 2013). Annual exports of this species peaked in 2001 with 9,103 individuals exported and have shown a gradual decline in exports (although with fluctuations between years) to 3,443 individuals in 2011 (UNEP-WCMC 2013). Most of these exports stemmed from Tanzania (84,444 total individuals from 1977 through 2011) and Mozambique (14,751 total individuals from 1977 through 2011; UNEP-WCMC 2013).
This species is collected for the international pet trade, with the greatest demand coming from the USA. Between 1977 and 2011, more than 111,000 individuals were exported for the pet trade. To date, there are no known or observed effects of removal for the pet trade on natural populations. However, because population sizes are not known, there are no estimates of survival or rates of population increase, and the taxonomy regarding the status of sub-species is uncertain, careful attention should be paid for any warning signs of declines. It is the third most heavily exported chameleon species on the globe. Careful attention should be paid to country exports to ensure that these are not detrimental to local populations.
This species is listed under Appendix II of CITES (CITES 2007). There are no other species-specific conservation measures in place for this species, however, in places its distribution coincides with protected areas. No further conservation measures are required at this time. There is uncertainty about the status of subspecies, so that research is needed to clarify the taxonomy of the species.
Chamaeleo dilepis has been assessed as Least Concern owing to its wide distribution, relatively high local abundance, and its tolerance of an anthropogenic environment. Although collected for the pet trade, there are currently no known or observed effects of removal for the pet trade on natural populations. Careful attention should be paid to detect early warning signs for declines in the population. There are gaps in our knowledge on the population biology and taxonomy of this species and refinement of this knowledge would assist in future assessments.
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