Taxonomic name: Norops sagrei (Cocteau in Duméril and Bibron, 1837)
Synonyms: Anolis sagrei (Cocteau in Duméril and Bibron, 1837)
Common names: Bahamian brown anole (English), brown anole (English), Cuban brown anole (English)
Organism type: reptile
Norops sagrei (brown anole) can be identified by its extensible throat fan that is often coloured yellow or reddish-orange and has a white line down the centre of its back. Norops sagrei is a habitat generalist that prefers the open vegetation of disturbed sites. It is a ground dweller but will venture several feet up into trees and shrubs. Norops sagrei compete with Anolis carolinensis and other introduced congeners. Norops sagre also prey on the hatchlings of Anolis carolinensis.
Norops sagrei (brown anole) is a “trunk ground ecomorph” sensu (Williams, 1983). It is described as having an extensible throat fan that can be yellow to red-orange. This species can be between 13 and 21.3cm. It also has enlarged toe pads and a short snout (Campbell, 2002). Brown anoles can erect a dorsonuchal crest when exposed to certain stimuli. The tail may have a crest-like ridge, but this is highly variable between individuals and should not be confused with the dorsonuchal crest. Also, the tail is laterally compressed. Females have a light line down the middle of their backs, but males do not. They tend to have a lighter mid-dorsal stripe that is distinct and often boldly patterned in females and often indistinct in males. Individuals change their colours and patterns throughout this range (Ann Paterson., pers. comm., 2005). Male colour is highly variable, ranging from light grey to nearly jet-black and plain coloured - to covered dorsally with irregular dark patches or chevrons and a network of light lines. Females exhibit a large range of colour, but nearly always have some type of obvious wavy dorsal pattern along the midline of their back (Enature.com Field Guide, undated).
ruderal/disturbed, urban areas
Norops sagrei (brown anole) is a ground dweller but will venture up several feet into trees and shrubs and prefers drier areas. Individuals occur primarily on the trunks of trees and on the ground (Rand and Williams, 1969). Campbell (2002) reports that the brown anole is a habitat generalist that generally prefers fairly open vegetation of disturbed sites.
The successful occupation of different types of habitats by Norops sagrei (brown anole) is attributed partly to its use of thermo-regulatory behaviours such as basking in solar radiation to select acceptable microclimates at different latitudes and altitudes (Rogowitz,1996). It is reported that brown anole when present, reduce the density and diversity of spiders upon which they feed (Wardle, 2002). Greene et al. (2002) state that, brown anole competes successfully with native green anole (see Anolis carolinensis in IUCN Red List of Threatened Species) and other introduced congeners. Campbell (2002) observes that without the brown anole, the native green anole occupies perches from ground to crown, but the presence of the brown anole causes the green anole to move higher, occupying trunks and crowns of trees. Brown anole demonstrate intra-guild predation (IGP), which is defined as killing and eating among potential competitors and have been reported to prey on the hatchlings of green anole. N. sagrei have also been observed consuming hatchling brown anoles, although this behaviour is not well understood and it is not known whether this behaviour is common (Nicholson et al. 2000).
Wardle (2002) reports findings which show that on islands without Norops spp. there is a great magnitude of leaf damage to sea grape (Coccoloba uvifera L.) which is indicative of a lizard-induced trophic cascade.
Tokarz et al. (2001) state that, "The dewlap of N. sagrei is a relatively large and often brighly coloured throat skin that can be extended and retracted in a variety of visual displays." The dewlap is considered to be a sexually dimorphic trait in anoles because males in most species have a larger dewlap than females. Moreover, there is evidence that the sexes differ in at least some neural and other morphological features that are involved in display of the dewlap. The sexes also differ in the social context in which the dewlap is used. Males in agonistic interactions extend their dewlaps more frequently than females and, unlike females, also display the dewlap during courtship. It has been proposed that the display of the dewlap by males may play an important role in species recognition, female mate choice, male-male competition, and even predator deterrence (West -Eberhard, 1983).
Native range: Norops sagrei (brown anole) is native to Cuba, the Bahamas, and their satellite islands (Campbell, 2002).
Known introduced range: North America, Hawai‘i, Jamaica (Campbell, 2002). They have also been introduced into Granada (Kolbe et al 2004).
Introduction pathways to new locations
Ship: Campbell (2002) states that, "N. sagrei arrived in the Florida Keys in the late 1800s and was inoculated to at least six separate ports in Florida in the 1940s."
Local dispersal methods
Boat: Parmley (2002) states that, "Campbell suggested vehicular rafting as the transport mode for northward dispersal of N. sagrei. He offers convincing evidence that Georgia brown anoles were transported along major interstates by northbound vehicles, probably "rafting" on recreational vehicles and boats, and/or in vehicles transporting landscaping plants."
Escape from confinement: Goldberg et al. (2002) states that, "The origin of the Hawaiian (Oahu) population is unknown, but it is believed that these anoles are descendents of released pets."
Campbell (2002) observes that, no control or eradication measures have been implemented for Norops sagrei (brown anole), in Florida (North America) where it has established. He further adds that this species would be very difficult if not impossible to completely eradicate due to its high density, high reproductive potential, and habitat generality.
Campbell (2002) states that, "Their native diet consists mainly of small arthropods, annelids, and molluscs."
Adult Norops sagrei (brown anoles) breed during the summer months (Lee et al. 1989; Tokarz et al. 1998). It is not clear when they establish territories. Although they become more conspicuous during the breeding season, there have been no empirical tests to determine their degree of territoriality during the non-breeding season. It is not clear whether they cease to defend territories at the end of the breeding season (Ann Paterson., pers. comm., 2005).
Reviewed by: Ann V. Paterson, Ph.D. Nell Mondy Chair, Department of Natural Sciences, Williams Baptist College USA
Compiled by: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG)
Last Modified: Saturday, 31 May 2008