Harvesting of chameleons from the East Usambara Mountains of Tanzania for the exotic pet trade is of concern due to the high rates of habitat loss in this region and the fact that many of the species are endemic or near endemic to this isolated montane forest. Export of the majority of chameleons found in the East Usambaras is regulated by their listing under CITES Appendix II. To ensure harvesting is sustainable, however, greater knowledge of the ecology of species is needed. We conducted this study in and around Amani Nature Reserve in the East Usambara Mountains during August 2009. We used transects on the forest edge and interior to gather baseline data relating to the ecology of chameleons and to assess if any effects of harvesting on populations could be detected. We compared abundance of chameleons between forest edge and interior, the age/size of species, and sex-ratios between these two habitat types. We observed 108 chameleons during surveys, representing seven species. Some species were restricted to forest interior while others were only found on forest edges. When comparing age/size and sex ratios of the most valued species for the exotic pet trade, Trioceros deremensis, we found a strong female sex-bias in adults only, and that adult females were larger than adult males. This is in contrast to reports in published literature showing that males are capable of growing larger than females. Based on the low abundance of some species, we suggest careful consideration of future export quotas under CITES. Further investigation into the potential reasons for the size and sex-ratios of T. deremensis is also needed.