Anolis cristatellusCommon Puerto Rican anole, Crested anole

Geographic Range

Crested anoles are native to neotropical areas, such as Puerto Rico (including the islands of Vieques, Culebra) and islands in the Caribbean (Anegada, Tortola, Virgin Gorda, Jost Van Dyke, St. John, and St. Thomas). They are also considered to be an introduced species in Florida, the Dominican Republic, and Costa Rica. It is uncertain exactly when this species was introduced into these areas, although there is some consensus that the crested anole was introduced into La Romana (Dominican Republic) before 1920. (Bartlett and Bartlett, 2006; Fitch, et al., 1989; Lever, 2003; MacLean, 1982)

Habitat

This is a perching species that is common in arboreal habitats. Males especially will use the trunks of trees as a way of displaying to other animals. Because they tend to remain close to the ground, they have been called a trunk-ground species. They may also perch on walls and fences, which are usually in more open areas and give a better vantage point for spotting prey or being seen by intruders in their territory. For this reason, crested anoles are commonly found in urban and suburban areas. (Bartlett and Bartlett, 2006; Brandley and de Queiroz, 2004; Collins and Conant, 1998; Gorman and Licht, 1974; MacLean, 1982; Rivero, 1998)

  • Range elevation
    0 to 548.64 m
    0.00 to 1800.00 ft

Physical Description

Crested anoles are known to reach lengths of 10 to 20.5 cm (4 to 8 in). Because this species has such a long tail, the SVL (snout-vent length) is usually just 7.5 cm for males and 5.7 cm for females. Females are much smaller than males. Hatchlings of this species are about 5.08 cm (2 in). Males can can vary from a grayish to a light brown color, and may have a crest on their tails. Males also have a dewlap, a flap of skin located under the neck that is able to be extended for use in communication. Dewlaps vary in color from yellow to red and may be lighter or darker depending on habitat moisture conditions. Females are drab and colored similarly to the ground, with a dark-bordered light stripe on their backs. Young males also have this dorsal stripe until they reach maturity. Females lack a tail crest and dewlap. This species has the ability to change color depending on its environment, lighting or mood. (Bartlett and Bartlett, 2006; Behler and King, 1979; Collins and Conant, 1998; Leal and Fleishman, 2004; MacLean, 1982; Perry, et al., 2004)

  • Sexual Dimorphism
  • male larger
  • sexes colored or patterned differently
  • ornamentation
  • Range length
    10 to 20.5 cm
    3.94 to 8.07 in

Development

Little is known about the specific development of crested anoles. Males tend to grow faster than females in most Anolis species. As individuals reach adulthood, this growth rate difference leads to sexual dimorphism. As juveniles, male crested anoles resemble females and their dewlap is not developed. This structure, and the dorsal crest, develops in males over time. (Bartlett and Bartlett, 2006; Behler and King, 1979; Collins and Conant, 1998; Losos, 2009; MacLean, 1982)

Reproduction

Males will regularly mate with females within their territory. In order to attract a mate, male anoles will approach females and perform a series of displays. These include bobbing the head, pushups, and displaying the dewlap. If the female acknowledges the male's display, she will bob her head in response. When the male mounts the female, she will arch her neck and the male will bite it. He then brings his tail closer to the female's and inserts his hemipene into the female's cloaca. However, females may reject the mating advances of a male before this point and if so, will flee instead of arching their neck. (Losos, 2009; MacLean, 1982)

Egg production in crested anoles is seasonal, with activity dropping in colder months and during the dry season. Crested anole females lay one or two eggs under logs and rock piles at two-week intervals. In general, when a female anole finds a spot to lay her eggs, she will nudge this spot with her snout. This behavior is then followed by digging with her forelegs. When the has been laid in the hole, the female will push it in further and then cover it with dirt. This species also participates in communal egg-laying, in which multiple females will use the same nest site to lay their eggs. The incubation period is 50 days, on average. (Gorman and Licht, 1974; Lever, 2003; Losos, 2009; Rand, 1967)

  • Breeding interval
    Crested anoles breed regularly throughout the year, although the frequency drops during colder and drier months.
  • Breeding season
    Breeding may occur at any time of the year. Average incubation period is 50 days.
  • Range number of offspring
    1 to 2 (every two weeks)

With the exception of the nutrients present in the egg and digging a hole in which to lay them, crested anoles do not contribute further to the success of their offspring. (Losos, 2009)

  • Parental Investment
  • no parental involvement
  • pre-fertilization
    • provisioning
    • protecting
      • female

Lifespan/Longevity

Little is known about the lifespan of crested anoles in the wild or in captivity. Several other Anolis species, however, have been reported to have average lifespans of about 7 years in captivity. It has been determined that the lifespan of an anole is strongly linked to the number of predators who share their habitat. (Losos, 2009; de Magalhaes and Costa, 2009)

  • Average lifespan
    Status: captivity
    7 years

Behavior

Crested anoles are diurnal lizards that use perching as a means of warding off other males, attracting females, and foraging for foods such as insects, fruit, frogs, and even other lizards. Generally, crested anoles perch parallel to the tree with their head facing the ground. Although, they can climb higher than 3m, they tend to prefer areas where sunlight is more plentiful, such as fence posts, tree trunks, or the walls of buildings. Males will climb to the top of the trees at night to sleep, while females and younger males stay lower. (Bartlett and Bartlett, 2006; Behler and King, 1979; Collins and Conant, 1998; Losos, 2009; MacLean, 1982; Rivero, 1998)

This species is extremely territorial. It uses threat displays that resemble pushups and extensions of the dewlap. Head-bobbing is also common in these displays. In most cases the male will make these threat displays from a perching position in their territory. This will alert any other males in the area of their ownership of that territory. These behaviors are also very similar to mating and anti-predator displays. If these displays fail to chase away other males, they will typically fight with each other over territories and access to females. (Leal and Fleishman, 2004; Losos, 2009; Nicholson, et al., 2007)

  • Range territory size
    1.5 to 19 m^2

Home Range

Adult crested anoles typically defend territories on trees, walls, or shrubs. The adult males usually occupy territories until death. However, young anoles usually move from territory to territory. Adult females occupy much smaller territories and will usually overlap with a male's. Crested anoles show weak orientation skills and will have a difficult time returning to their territory if they are placed outside their realm of familiarity. Though both males and females have homing capabilities, they are much weaker in females. (Fitch, et al., 1989; Jenssen, 2002; Philibosian, 1975)

Communication and Perception

Crested anoles rely heavily on visual cues in order to communicate with one another. Generally, males who defend territories exhibit this behavior. These displays include pushups, extensions of the dewlap, head bobbing, biting, and tail lashing. These behaviors convey one of two meanings, either telling a potential mate that the male is interested, or warning other males that they are intruding into their territory. The dewlap is a very important part of anole species' intraspecific and interspecific communication, as it varies in color across species. This visual cue is very important when defending a territory from a potential threat. (Leal and Fleishman, 2004; MacLean, 1982; Nicholson, et al., 2007; Perry, et al., 2004)

  • Communication Channels
  • visual

Food Habits

Crested anoles are primarily insectivores, eating prey that range in size from ants to large roaches. They also feed on small fruits, frogs, and even other lizards (including the young of their own species). Crested anoles are foragers and typically scan their environment for food from a perching position on the trunks of trees or the sides of buildings. (MacLean, 1982; Roughgarden, 1995)

  • Animal Foods
  • amphibians
  • reptiles
  • insects
  • terrestrial non-insect arthropods
  • Plant Foods
  • fruit

Predation

In Puerto Rico, crested anoles are primarily eaten by birds, mongoosex, and snakes, including Puerto Rican racers (Alsophis portoricensis). However, coqui frogs (Eleutherodactylus coqui) and other lizards (Ameiva exsul) have also been known to eat anoles in Puerto Rico. In the Lesser Antilles (St. John, Virgin Gorda, Jost Van Dyke, Tortola, and St. Thomas), American kestrels (Falco sparverius) and early-eyed thrashers (Margarops fuscatus) are the most important bird predators of anoles. (Leal and Rodriguez-Robles, 1995; Roughgarden, 1995)

Crested anoles exhibit several different behaviors when confronted by predators. These include expression of the dewlap, body thrashing, biting, tail lashing, head-bobbing, and pushups. These can be used separately or in combination to escape predation. (Leal and Rodriguez-Robles, 1995; Roughgarden, 1995)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Crested anoles serve as predators of insects and other small animals and prey to larger carnivorous organisms. In locations where they have been introduced, they have negatively impacted other anoles that were already present in the ecosystem. For example, in La Romana (Dominican Republic), Anolis chlorocyanus are now confined to trees that are slippery, to avoid predation by larger, non-native crested anoles. Cat liver flukes (Platynosomum concinnum) use crested anoles as a secondary intermediate host after it has already infected the snail species Subulina octona. (Dyer, et al., 2001; Fitch, et al., 1989; Goldberg, et al., 1998; Griffiths, 1978; Lever, 2003; Losos, 2009; Schall and Vogt, 1993)

Commensal/Parasitic Species
  • Plasmodium azurophilum (Order Haemosporida, Phylum Apicomplexa)
  • cat liver flukes (Platynosomum concinnum)
  • Mesocoelium danforthi (Subclass Digenea, Phylum Platyhelminthes)
  • Ascarops sp. (Family Spiruridae, Phylum Nematoda)
  • Physocephalus sp. (Family Thelaziidae, Phylum Nematoda)
  • Parapharyngodon cubensis (Family Pharyngodonidae, Phylum Nematoda)
  • Skrjabinoptera leiocephalorum (Family Physalopteridae, Phylum Nematoda)
  • Centrorhynchus sp. (Order Polymorphida, Phylum Acanthocephala)

Economic Importance for Humans: Positive

Because crested anoles are mostly insectivores, they are important factors in controlling pest populations in the areas where they coexist with humans. Crested anoles are also becoming more popular as pets. (Bartlett and Bartlett, 1997; MacLean, 1982)

As an invasive species in many areas, crested anoles have been subject to different types of habitats. Because introduction in a new habitat can lead to the natural selection of traits that may not have been selected for in their native habitat (for example dewlap design), crested anoles have become a popular model organism in evolutionary studies. (Glor, et al., 2007; Leal and Fleishman, 2004; Roughgarden, 1995)

  • Positive Impacts
  • pet trade
  • research and education
  • controls pest population

Economic Importance for Humans: Negative

There are no known adverse effects of crested anoles on humans.

Conservation Status

At this time, crested anoles have no special conservation status.

Contributors

Dylan McDaniel (author), Radford University, Karen Powers (editor), Radford University, Kiersten Newtoff (editor), Radford University, Melissa Whistleman (editor), Radford University, Jeremy Wright (editor), University of Michigan-Ann Arbor.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

arboreal

Referring to an animal that lives in trees; tree-climbing.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

diurnal
  1. active during the day, 2. lasting for one day.
fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

indeterminate growth

Animals with indeterminate growth continue to grow throughout their lives.

insectivore

An animal that eats mainly insects or spiders.

introduced

referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

polygynous

having more than one female as a mate at one time

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

sexual ornamentation

one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

urban

living in cities and large towns, landscapes dominated by human structures and activity.

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

year-round breeding

breeding takes place throughout the year

References

Bartlett, P., R. Bartlett. 1997. Anoles, Basilisks, and Water Dragons. Hauppauge, NY: Barron's Educational Series.

Bartlett, R., P. Bartlett. 2006. Guide and Reference to the Crocodilians, Turtles, and Lizards of Eastern and Central North America (North of Mexico). Gainesville, FL: The University Press of Florida.

Behler, J., W. King. 1979. The Audubon Society Field Guide to North American Reptiles and Amphibians. New York: Alfred A. Knipf, Inc..

Brandley, M., K. de Queiroz. 2004. Phylogeny, ecomorphological evolution, and historical biogeography of the Anolis cristatellus series. Herpetological Monographs, 18/1: 90-126.

Collins, J., R. Conant. 1998. A Field Guide to Reptiles and Amphibians of Eastern and Central North America. New York, NY: Houghtton Mifflin Company.

Dyer, W., L. Bunkley-Williams, E. Williams Jr.. 2001. Some helminth parasites of Anolis stratulus and Anolis cristatellus (Sauria: Polychrotidae) in Puerto Rico. Transactions of the Illinois State Academy of Science, 94/3: 161-165.

Fitch, H., R. Henderson, H. Guarisco. 1989. Aspects of the ecology of an introduced anole: Anolis cristatellus in the Dominican Republic. Amphibia-Reptilia, 10/3: 307-320.

Glor, R., J. Michele, A. Larson. 2007. Polymorphic microsatellite loci for the Puerto Rican crested anole (Anolis cristatellus) and their amplification in related Puerto Rican species. Conservation Genetics, 8/6: 1491-1493.

Goldberg, S., C. Bursey, H. Cheam. 1998. Helminths of Six Species of Anolis Lizards (Polychrotidae) from Hispaniola, West Indies. Journal of Parasitology, 84/6: 1291-1295.

Gorman, G., P. Licht. 1974. Seasonality in ovarian cycles among tropical anolis lizards. Ecology, 55/2: 360-369.

Griffiths, H. 1978. A Handbook of Veterinary Parasitology: Domestic Animals of North America. Minneapolis, MN: University of Minnesota Press.

Jenssen, T. 2002. Spatial awareness by the lizard Anolis cristatellus: Why should a non-ranging species demonstrate homing behavior?. Herpetologica, 58/3: 364-371.

Leal, M., L. Fleishman. 2004. Differences in visual signal design and detectability between allopatric populations of anolis lizards. The American Naturalist, 163/1: 26-39.

Leal, M., J. Rodriguez-Robles. 1995. Antipredator responses of Anolis cristatellus. Copeia, 1995/1: 155-161.

Lever, C. 2003. Naturalized Reptiles and Amphibians of the World. New York, NY: Oxford University Press.

Losos, J. 2009. Lizards in an Evolutionary Tree: Ecology and Adaptive Radiation in Anoles. Berkeley and Los Angeles, California: University of California Press.

MacLean, W. 1982. Reptiles and Amphibians of the Virgin Islands. London and Basingstoke: Macmillan Education Limited.

Nicholson, K., L. Harmon, J. Losos. 2007. Evolution of Anolis lizard dewlap diversity. PLoS ONE, 2/3: e274.

Perry, G., K. Levering, I. Girard, T. Garland. 2004. Locomotor performance and social dominance in male Anolis cristatellus. Animal Behavior, 67: 37-47.

Philibosian, R. 1975. Territorial behavior and population regulation in the lizards, Anolis acutus and A. cristatellus. Copeia, 3: 428-444.

Rand, S. 1967. Egg laying in anoline lizards. Herpetoligica, 23/3: 227-230.

Rivero, J. 1998. Los Anfibios y Reptiles de Puerto Rico. Puerto Rico: University of Puerto Rico.

Roughgarden, J. 1995. Anolis Lizards of the Caribbean: Ecology, Evolution, and Plate Tectonics. New York, NY: Oxford University Press.

Schall, J., S. Vogt. 1993. Distribution of malaria in Anolis lizards of the Luquillo forest, Puerto Rico: Implications for host community ecology. Biotropica, 25/2: 229-235.

de Magalhaes, J., J. Costa. 2009. A database of vertebrate longevity records and their relation to other life-history traits. Journal of Evolutionary Biology, 22/8: 1770-1774.