Spectacled caimans are carnivorous generalists. Prey items change as they grow from smaller to larger caimans. Prey can include insects, snails, shrimp, crabs, fish, lizards, snakes, turtles, birds, and mammals. Spectacled caimans have at least 105 prey items reported in their diet. Cannibalism can occur, especially under drought conditions, when many caimans of different sizes are concentrated in small areas. However this species can be surprisingly unaggressive and tolerant of temporarily dense concentrations during the dry season.
Animal Foods: birds; mammals; amphibians; reptiles; fish; carrion ; insects; terrestrial non-insect arthropods; mollusks; aquatic crustaceans
Primary Diet: carnivore (Eats terrestrial vertebrates, Piscivore , Insectivore , Eats non-insect arthropods, Molluscivore , Scavenger )
During nesting time, tegu lizards (Tupinambis sp.) can destroy up to 80% of caiman nests in some places. Coatis (Nasua narica) and foxes also raid nests. Juveniles are eaten by large fish, wading birds, large snakes, and other crocodilians. Adult spectacled caimans are able to defend themselves from most potential predators, except humans.
Known Predators:
Anti-predator Adaptations: cryptic
Spectacled caimans are small to medium-sized crocodilians generally 1.5 to 2.1 meters in length. Historically, maximum reported length was 3 m. At current levels of exploitation, few specimens exceed 2.5 m in length. Females are smaller than males. Average adults are a dull olive to nearly black in color with variable yellow or black crossbands. They have long snouts and their fourth mandibular tooth is not visible from the outside of their closed jaw. Juveniles are yellowish in color with darker bands and spots. A feature that helps to distinguish Caiman crocodilus from other, sympatric crocodilians is the presence of a bony infra-orbital bridge between the eyes. Subspecies vary in color and skull size.
Range mass: 7 to 58 kg.
Average mass: 40 kg.
Range length: 1.5 to 3 m.
Average length: 2 m.
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry
Sexual Dimorphism: male larger
There is very little known about the lifespan of Caiman crocodilus. The longest known lifespan in the wild was estimated at about 60 years old. However, 30 to 40 years might be more normal. The average captive lifespan is 20 years, with a minimum record of 24 years.
Range lifespan
Status: wild: 60 (high) years.
Range lifespan
Status: captivity: 24 (high) years.
Typical lifespan
Status: wild: 30 to 40 years.
Average lifespan
Status: captivity: 20 years.
Spectacled caimans are found in freshwater habitats as well as some salt water habitats. Rivers and wetlands, usually slow moving water, are preferred. They are found in both deep and shallow water, as they only need enough depth to submerge their bodies.
Range elevation: 800 (high) m.
Habitat Regions: tropical ; terrestrial ; saltwater or marine ; freshwater
Aquatic Biomes: lakes and ponds; rivers and streams; coastal ; brackish water
Wetlands: marsh ; swamp ; bog
Other Habitat Features: riparian ; estuarine
Caiman crocodilus, the spectacled, common, or brown caiman, is a crocodilian native to northern South America, Central America, and certain parts of the Caribbean. They are native to the following countries: Brazil, Colombia, Costa Rica, Ecuador, El Salvador, French Guiana, Guatemala, Guyana, Honduras, Mexico, Nicaragua, Panama, Peru, Suriname, Trinidad, Tobago, and Venezuela. They have been introduced into Florida, Cuba, and Puerto Rico.
Biogeographic Regions: nearctic (Introduced ); neotropical (Native )
Spectacled caimans are predators of aquatic invertebrates, fish, and other aquatic and shoreline vertebrates. In their native range they are important members of riparian shoreline and aquatic communities. Where spectacled caimans have been introduced outside of their normal range, spectacled caimans may have unpredictable, perhaps deleterious effects on prey species.
Within their native range, spectacled caimans are usually the most abundant crocodiles and are the most heavily harvested species by humans for the hide industry.
Positive Impacts: pet trade ; food ; body parts are source of valuable material; controls pest population
Spectacled caimans are potentially dangerous to humans and pets, and they occasionally attack livestock. Their smaller size compared to other crocodilians makes them less of a threat. They become shy and avoid humans in areas where they are frequently hunted. Spectacled caimans have been introduced outside their natural range, such as in southern Florida, and possible negative effects on local naive wildlife are in need of study.
Negative Impacts: injures humans (bites or stings)
Some weeks after courtship and copulation, with internal fertilization, females lay their oval, hard-shelled eggs in a newly made mound of leaf litter and other vegetation. Once the eggs are laid, the female will cover the nest. Females, and sometimes males, guard their eggs against nest predators. Temperature influences sex determination during incubation. An average nest temperature of 30 degrees C will produce mostly females and 34 degrees will produce mostly males. After an incubation period of 65 to 104 days the babies will hatch out of their eggs and move to the nearest water, with some help from their parents. Once the juveniles have hatched, they will stay near their parents for about 1.5 years. Juveniles then grow to adult size at around 1.2 to 1.4 meters in length. Once juveniles reach minimum adult size, they are able to reproduce. If they survive long enough, they can continue to grow until reaching a size that may exceed 2.4 meters.
Development - Life Cycle: temperature sex determination
In 1986 and 1988 spectacled caimans were listed by the United States Fish and Wildlife Service as a threatened species. This was due to increased hunting pressure on their populations. Caimans are heavily harvested for their skins to make leather products. The pet and curio trade has also had some degree of responsibility for local population declines. Spectacled caiman populations are still relatively stable in some parts of their range, although they are severely depleted or extirpated in many local areas, especially near human population centers.
US Federal List: threatened
CITES: appendix ii
State of Michigan List: no special status
IUCN Red List of Threatened Species: lower risk - least concern
Spectacled caimans use taste, touch, sound, and visual senses for social and reproductive communication. The ability to detect vibrations in the water may aid in prey detection.
Communication Channels: visual ; tactile ; acoustic ; chemical
Other Communication Modes: vibrations
Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical
Mating typically occurs in the wet season from April to August, depending on local climatic conditions. Males can breed with multiple females and females can breed with multiple males. Courtship behavior involves prospective mates swimming together, rubbing backs, bellowing, touching snouts, circling each other, and bubble-blowing. Both sexes use these behaviors to attract their mates. After a female mates with a male she will build a nest in the males territory. There, the male and female will guard the nest, eggs, young, once they are hatched.
Mating System: polygynandrous (promiscuous) ; cooperative breeder
Spectacled caimans reach sexual maturity at sizes of about 1.2 meters for females and 1.4 meters for males, corresponding to from 4 to 7 years old. Social status affects growth rate and reproduction. Some younger, smaller caimans will be unable to mate because of social stress because of the presence of larger, more dominant caimans. Courtship and copulation occurs between May and August. Eggs are laid from July to November, depending on local climatic conditions. Females lay from 10 to 30 eggs. Incubation usually requires between 65 and 104 days. Sex is determined by temperature in the nest about midway through incubation. The decomposing vegetation in the nest, which may be a meter high and 2 meters in diameter, may help retain temperatures at the proper level. After hatching, the parents may excavate the juveniles from the nest and help them out of the eggshell. Once emerged, juveniles stay near their parents for approximately 1.5 years, receiving some protection from predators.
Breeding interval: Spectacled caimans breed for about four months during the wet season each year.
Breeding season: Spectacled caimans breed from May through August.
Range number of offspring: 10 to 40.
Average number of offspring: 22.
Range gestation period: 65 to 104 days.
Average time to independence: 1.5 years.
Range age at sexual or reproductive maturity (female): 4 to 7 years.
Average age at sexual or reproductive maturity (female): 6 years.
Range age at sexual or reproductive maturity (male): 4 to 7 years.
Average age at sexual or reproductive maturity (male): 6 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous
After copulation, females, sometimes assisted by males, build a nest out of leaf litter. Females lay their eggs in the nest and then cover it with more leaf litter. Females, and occasionally males, guard the nest from predators until they hear the babies call with grunt-like squeaks. Females then help uncover eggs and break the shells open to get the juveniles out. At that point, juveniles stay near their mother, and sometimes within the male parent's territory, for around 1.5 years for additional protection from predators. The parents may incidentally provide some food scraps for the juveniles but, for the most part, juvenile caimans catch food for themselves. After about 1.5 years with their parents, juveniles disperse from their parent's territory. In some situations, young caimans remain closer to their parents for longer periods.
Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Male, Female); pre-independence (Provisioning: Female, Protecting: Female)
The spectacled caiman (Caiman crocodilus), also known as the white caiman,[6] common caiman,[7] and speckled caiman,[8] is a crocodilian in the family Alligatoridae. It is brownish-, greenish-, or yellowish-gray colored and has a spectacle-like ridge between its eyes, which is where its common name come from. It grows to a length of 1.4–2.5 m (4 ft 7 in – 8 ft 2 in) and a weight of 7–40 kg (15–88 lb), with males being both longer and heavier than females. Its diet varies seasonally, commonly consisting of crabs, fish, small mammals, amphibians and snails. Breeding occurs from May to August and 14–40 eggs are laid in July and August. This crocodilian has a large range and population; it is native to much of Latin America, and has been introduced to the United States, Cuba, and Puerto Rico.
The spectacled caiman was described by Carl Linnaeus in 1758, originally as Lacerta crocodilus.[2] It has since been redescribed several times, including as Caiman sclerops by Schneider in 1801.[5] Although Caiman crocodilus is now the scientific name of the species, some scientists still prefer using sclerops, as having crocodilus as the scientific name for a caiman may cause confusion.[9]
The spectacled caiman has four recognized subspecies:[7][10]
The yacare caiman (Caiman yacare), while previously thought to be a subspecies of C. crocodilus, is now usually considered a separate species.[2]
The Rio Apaporis caiman was believed to have become extinct by 1981, when the last known specimen died in a zoo. However, a specimen was captured for the television show Extinct or Alive in 2019 and identified by DNA sampling.[11][12][13]
The spectacled caiman is a small to medium-sized crocodilian. Females generally grow to no more than 1.08 to 1.4 m (3 ft 7 in to 4 ft 7 in) (the lower size typical upon the onset of sexual maturity), but can rarely grow to nearly 2 m (6 ft 7 in). Adult males can regularly reach 1.5 to 1.8 m (4 ft 11 in to 5 ft 11 in) while large mature ones grow to 2.0 to 2.5 m (6 ft 7 in to 8 ft 2 in), although relatively few get to the upper size.[14] The maximum reported size for the species is 2.64 m (8 ft 8 in).[15] The body mass of most adults is between 7 and 40 kg (15 and 88 lb), with males typically being considerably heavier than females. Some males in the Llanos have been reported to grow to up to 58 kg (128 lb).[16]
The upperside of the species is mostly brownish-, greenish-, or yellowish-gray colored and has dark brown crossbands,[15] with a lighter underside. It has a greenish iris.[17] and wrinkled eyelids.[8] It changes color seasonally – during colder weather, the black pigment within its skin cells expands, making it appear darker.[18] The species has an enlarged 4th tooth, and the teeth in its lower jaw penetrate into a socket in its upper jaw. It has a long snout that tapers moderately, with an unexpanded tip.[19] Several ridges begin in front of its eyes and travel to the tip of its snout.[17] Its common name comes from a bony ridge between its eyes, which gives the appearance of a pair of spectacles.[20] The spectacled caiman is the most widely distributed New World crocodilian, and is the most geographically variable species in the Americas, making it a highly adaptable species.[21]
The spectacled caiman can move rapidly when threatened, but is usually immobile, resting on shores or partly in water. In the rainy season, males become aggressive and territorial.[16]
Usually hunting at night, the diet of the spectacled caiman varies seasonally.[16] During the wet season, it primarily eats snails and freshwater crabs, while it mostly eats fish in the dry season. Smaller specimens tend to eat more insects and freshwater shrimp, while larger ones more frequently consume mammals and fish.[22] Overall, the most common animals in this species' diet are crabs, fish, mammals, and snails.[23] Other animals that have been known to be a part of its diet include amphibians, arachnids, birds, myriapods, reptiles (lizards, snakes, and turtles), and small mammals.[22][24] Older animals are capable of taking larger, mammalian prey (e.g. wild pigs).[25] Cannibalism has been reported under such conditions.[25] It has also been known to eat plant matter; in a study of this species in Puerto Rico, about 55% of adult specimens had plants in their diet, primarily grass and seeds. About 8% of adults and 6% of juveniles in the study had gastroliths in their stomach as well.[26] Although the species has been suggested to control piranha populations, piranhas have not been found to be a normal diet component, unlike the yacare caiman. According to the Crocodilian Species List, it is probably a generalist species, being able to adapt to a variety of prey.[14][27]
The spectacled caiman uses nine different vocalizations and 13 visual displays to communicate with individuals of its species.[16] Both adults and young produce calls for group cohesion. Males are known to communicate by moving their tail to a certain position, such as making it vertical or arched. Juveniles vocalize when in distress and adult females emit calls to warn young of threats.[2]
The spectacled caiman reaches sexual maturity from four to seven years old, at a length of 1.2 metres (3.9 ft) for females and 1.4 metres (4.6 ft) for males. Usually, the more dominant individuals mature more quickly. Specimens choose mates and engage in copulation from May to August, the wet season.[14] The females build nests as a mound of dense vegetation, in areas that are close to water but not at risk of being flooded. The nests are over 1 metre (3.3 ft) in diameter and can be 40 centimetres (16 in) high, but the exact size depends on the resources available. Eggs are laid in July and August; the species very rarely nests in the winter, as the temperature is too low for the eggs.[16][28] Clutch size is 22 on average, but can range from 14 to 40.[14] Larger females have been known to lay larger eggs compared to smaller females.[29] Females stay close to their nests during the incubation period, as several species, such as lizards in the genus Tupinambis, have been known to destroy nests and prey on the eggs.[14] White-nosed coatis and foxes also raid nests.[22] Flooding and human egg collecting can also be a threat to the nests.[16] In a study in the Central Amazonia assessing reproductive similarities between C. crocodilus and Melanochus niger, research found that they indiscriminately separate their nests at larger distances than other species in this family, most likely to avoid predation.[30]
Temperature is important to the developing eggs, so females build their nests in a way that insulates them from extreme temperature changes. As the vegetation in the nests decays, the nests produce heat which can keep the eggs about 5 °C (9 °F) warmer than if they were insulated by mud alone.[28] Heat not only incubates the eggs, but also determines the sex of the developing caimans (temperature-dependent sex determination). When the temperature inside the nest is about 32 °C (90 °F) or higher, the caimans become female, and otherwise become male.[31] Young hatch after 90 days,[20] with 20–25 percent of eggs hatching successfully.[16] They are yellow with black spots, a coloration which fades away as they grow older,[14] with a length of 20–23 centimetres (7.9–9.1 in).[16] Parents raise their young in crèches, with one female taking care of her own, as well as several others' offspring.[32] They take care of their young for 12–18 months.[10] Young are threatened by various predators, such as raptors (like hawks)[33] and wader birds (like herons),[22] causing most to die in their first year.[16] These juveniles are also preyed upon by large fish, large snakes (such as anacondas), and other crocodilians.[22]
The spectacled caiman has the largest range of any caiman,[9] and of any New World crocodilian.[10] It is found in various countries throughout the Americas. It lives in Brazil, Colombia, Costa Rica, Ecuador, El Salvador, French Guiana, Guatemala, Guyana, Honduras, Mexico, Nicaragua, Panama, Peru, Suriname, Trinidad and Tobago, and Venezuela, and may also be extant in Belize and Bolivia. It has been introduced to Isla de la Juventud in Cuba, Puerto Rico, and Florida in the United States;[2] in the latter, it is sometimes mislabeled as the American alligator (Alligator mississippiensis).[14] Invasive populations have become established in South Florida, with isolated records further north in the state.[32] It is intolerant to cold climates, so its range is unlikely to expand to further north than Florida.[34] It usually lives in forests, inland bodies of fresh water (such as wetlands and rivers), grasslands, shrublands, and savannas, but is very adaptable.[2] It prefers habitats with calm water containing floating vegetation, usually flooding and drying seasonally. It is most common in low-lying areas, but has been found at elevations of up to 800 m (2,600 ft).[16] In Brazil, the species lives in the rivers Amazon, Araguaia, Araguari, Itapicuru, Rio Negro, Paranaíba, Solimões, Tapajós, Tocantins, and Xingu.[8] It is able to live in human-inhabited areas.[17]
The adult population of this crocodilian is estimated to be in the millions and stable.[2] About four million spectacled caimans are found in Venezuela and surveys have shown that it is expected to increase.[18] This is an example of how well the species is able to adapt.[14] However, populations are not doing well in other countries, such as Peru.[18] The population in a single area can be determined the easiest by counting individuals in the dry season at night.[16]
The skin of the spectacled caiman is covered with osteoderms, which previously caused it to not be a major commercial target for its skin. However, harvesting of the skins of this caiman and others became very common in the 1950s, due to the declining stocks of crocodiles.[10] Throughout the 1970s and 1980s, the species was frequently traded, causing its population to decrease in some areas. Its skin was often exported from South America and utilized primarily for leather; at least 6 million skins were exported from Colombia from 1996 to 2015. However, conservation efforts since have caused a significant reduction in the number of skins exported.[2] In most countries, hunting this species is legal. Venezuela permits hunting every fall, provided the total number of kills in the season does not exceed 150,000.[18] Because of its adaptability and wide distribution, habitat loss does not affect the species significantly globally.[2] It is reasonably resilient to hunting as well, as hunters usually focus on large males and the species reproduces at a small size.[10] However, it is severely threatened in Colombia,[14] primarily the subspecies C. c. fuscus and sometimes C. c. crocodilus.[35]
The spectacled caiman benefits from overhunting of competitive species which occupy the same home range, as this allows it to access resources normally lost to these other species. Specimens that have been introduced to Cuba, Puerto Rico, and the United States negatively impact the native animals there. They are believed to have been the main reason for the likely extirpation of the Cuban crocodile (Crocodylus rhombifer) from the Isla de la Juventud, Cuba.[14] The species has a similar diet to the black caiman (Melanosuchus niger) – both species eat mostly insects as juveniles and fish as adults. This causes interspecific competition, making it more difficult for the black caiman's population to recover.[36] The spectacled caiman lives in parts of the Amazon rainforest that the black caiman was extirpated from.[10]
Conservation programs for this species are used in many countries. The most common form of conservation is the use of cropping, which consists of manually reducing the numbers of several wild and abundant species. Long-term effects of cropping have yet to be discovered; more surveys have been recommended. Farming or ranching programs have also been used as conservation efforts for the species, but seem to be more expensive and possibly less effective.[14] A conservation program in Colombia, which existed from 2004 to 2006, bred spectacled caimans in captivity and released the young into the wild at one year old. A similar program released over 15,000 juveniles into wetlands from 2005 to 2009.[2] Previously, Colombia restricted the exportation of spectacled caiman skins to ones shorter than 1.2 metres (3.9 ft), but as of 2011 there are now only size limits for some individual pieces of the skin, rather than the overall size of the skin. These limits are less effective, as large skins could accord with the size limits if cut and trimmed.[35] According to the International Union for Conservation of Nature (IUCN), further surveys of the species would help with future conservation plans.[2]
The spectacled caiman is listed as a species of least concern on the IUCN Red List, due to its large range and population globally, following two assessments as threatened in 1986 and 1988.[2] The subspecies C. c. crocodilus is on Appendix II of CITES,[5] C. c. apaporiensis Appendix I,[37] and C. c. fuscus Appendix II.[38]
The spectacled caiman (Caiman crocodilus), also known as the white caiman, common caiman, and speckled caiman, is a crocodilian in the family Alligatoridae. It is brownish-, greenish-, or yellowish-gray colored and has a spectacle-like ridge between its eyes, which is where its common name come from. It grows to a length of 1.4–2.5 m (4 ft 7 in – 8 ft 2 in) and a weight of 7–40 kg (15–88 lb), with males being both longer and heavier than females. Its diet varies seasonally, commonly consisting of crabs, fish, small mammals, amphibians and snails. Breeding occurs from May to August and 14–40 eggs are laid in July and August. This crocodilian has a large range and population; it is native to much of Latin America, and has been introduced to the United States, Cuba, and Puerto Rico.
