Chameleons are not native to Hawaii; they are non-indigenous species. The unique and isolated Hawaiian Islands did not evolve with any native reptiles or land mammals, meaning any established reptile population was introduced by humans. The most common species is the Jackson’s Chameleon, which is widely established and classified by the state government as a harmful invasive species. This classification is rooted in the significant ecological threat these reptiles pose to Hawaii’s delicate native plant and animal life, presenting a continuing challenge for conservation managers.
Defining the Status of Chameleons in Hawaii
The primary species of chameleon found in Hawaii is the Jackson’s Chameleon (Trioceros jacksonii), which is native to the high-altitude forests of East Africa (Kenya and Tanzania). This species has successfully established feral populations across Oʻahu, Maui, and Hawaiʻi Island (the Big Island). The Veiled Chameleon (Chamaeleo calyptratus), native to Yemen and Saudi Arabia, has also been illegally introduced, though its populations are less widespread.
The State of Hawaii officially classifies chameleons as “Injurious Wildlife.” This regulatory status confirms the species is known to be harmful to indigenous wildlife and plants, agriculture, or constitutes a public nuisance. This designation strictly prohibits the transport of chameleons between islands to prevent the establishment of new populations where they are not yet widespread, such as Kauaʻi and Lanaʻi. Penalties for violating these regulations can include substantial fines.
The Pathways of Introduction and Establishment
The founder population of the Jackson’s Chameleon was introduced to Oʻahu in 1972 via the exotic pet trade. A licensed pet store owner imported several dozen chameleons from Kenya. When the reptiles arrived in poor condition, some were intentionally released outside to recover, initiating the feral population.
This single introduction event led to the widespread population now present across the islands. The species thrived because Hawaii’s wet, mid-elevation forests closely mimic the cool, moist montane habitat of their native East Africa. Furthermore, the Hawaiian Islands lack the natural predators and diseases that regulate the chameleon population in its native range. Once established on Oʻahu, chameleons were subsequently moved to other islands through intentional or accidental human transport.
Ecological Consequences for Native Species
The chameleons’ presence represents a significant new predatory pressure on Hawaii’s native fauna, which is often defenseless due to its isolated evolution. Jackson’s chameleons are highly effective generalist predators, using specialized projectile tongues to capture prey. Their diet includes a wide array of invertebrates that have not evolved defenses against this type of specialized arboreal predator.
A major concern is the direct predation on endemic Hawaiian insects, arthropods, and land snails. Stomach content analysis of wild-caught chameleons has revealed the presence of native taxa, including planthoppers, beetles, and case-bearing caterpillars, indicating a clear impact on local invertebrate populations. Crucially, chameleons have been documented preying on critically endangered Hawaiian tree snails, such as Achatinella mustelina. The tree snails are slow-moving and particularly vulnerable, and predation by chameleons poses a direct threat to the survival of these rare species.
The chameleons also compete with native insectivorous birds and other native lizards for limited food resources. By consuming vast numbers of native insects, they deplete the food supply necessary for the survival of indigenous insectivores. This competition contributes to the continued decline of native species and disrupts the natural flow of energy within native biological communities.
State and Local Management Strategies
Official responses to the chameleon populations are focused on control and prevention, particularly in ecologically sensitive areas. The Department of Land and Natural Resources (DLNR) oversees control programs that often rely on extensive, labor-intensive manual removal efforts. These efforts typically target high-value conservation sites where endangered native species are concentrated.
Preventative measures and strict regulation are also central to the management strategy. The classification of chameleons as Injurious Wildlife strictly prohibits their inter-island transport, aiming to prevent their spread to islands like Kauaʻi and Lanaʻi, where they are not yet fully established. Furthermore, the state regulates the export of chameleons, denying commercial export permits to avoid creating a financial incentive for breeding the species in Hawaii.
Public awareness campaigns encourage residents to report chameleon sightings, supporting Early Detection Rapid Response (EDRR) efforts. The Hawaii Department of Agriculture also maintains an amnesty program, allowing individuals to turn in illegally possessed chameleons without fear of prosecution. This combination of targeted removal, strict regulation, and public involvement is necessary to mitigate the continued threat posed by these established non-native reptiles.