Common Name:Common Caiman, Spectacled/Spotted/Brown Caiman
Latin Name:Caiman crocodilus
Family:Alligatoridae

caiman.jpg

Range:
Caiman can be found generally in all neotropic and warm climates around the world. Specifically, caiman species are found in the United States, Latin/South America, and China [1].

Abundance:
Caiman have been shown to be greatly abundant in the range of its location [1].

Coloration:
These caiman are named for their coloration. This species is spotted, speckled or striped in the distribution of these colors, with no set pattern. The colors are various shades of brown, grey, white, black and green. Coloration is generally random.

Morphology:
Studies have shown that the common caiman can range from 15-115cm [2], and can grow up to 2.5m, although not common [1]. Males grow larger than females. These animals walk with body perpendicular to the ground, with arms out to the sides. Males are generally 30-40% larger than females [3].

Reproductive cycle:
Sexual reproduction stage begins at the end of the dry season April-May for both male and female caiman. The reproduction cycle of the common caiman is peaked during the months of June-August, the general wet season in the tropics. Males are physiologically mature and able to reproduce at 75cm. Small males have a harder time reproducing due to “social factors”, presumably the competition by larger males and lack of acknowledgement by females. For the study on reproduction read, the average number of eggs per clutch was 22.2, and larger/growing females were able to produce a greater clutch size. There was no evidence or correlation between egg size and nest size. Nests are created with various woody materials or dug into the sand [3].

Habitat:
Caiman can develop in a variety of habitats; however, they need to be found in close proximity to water. They have been found in seasonally flood savannas [1], and neotropical rainforest. These animals are usually seen by humans when they are sun-bathing out of the water on a log or on shore.

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Caiman Habitat at Cahuita National Park


Ecology:
The caiman is an important apex predator at the top of the food-chain in the tropics. These animals are able to adapt because of their smaller size and their versatility in nesting and food, causing them to be abundant in the tropics.

Behavior:
Caiman are relatively aggressive animals. They can be found hunting through various methods. These were shown by Maroni, Boris et al.to be “trapping” (with the body perpendicular to the shore, the caiman captures prey swimming close to the shore), active
search (with the head under the water, the caiman searches for benthic prey), and jumping (leaping partially out of the water and capturing fish or other under water invertebrates prey)” [1: 769]. They can also hunt down prey on land, although they are not excessively fast. Other behavior includes sun-bathing and resting in the mud on logs and on the bank due to their cold-blooded nature.

Diet:
These animals are carnivorous. They feed on benthic organisms, invertebrates, fish, and smaller mammals. Also, they have been shown to feed on other caiman and other reptiles [1].

Interactions with other Species:
The only predator they has been show to fight/eat the caiman is the jaguar. This paper found that the C. crocodilus, being the smaller species, was more vulnerable to be attacked and killed by the Jaguar because of size and its time spend on land. The jaguar will also feed on the caiman’s eggs which are in nests on land. Other caiman species such as the black caiman (Melanosuchus niger) will also feed on the smaller common caiman [4].

Personal Experience:
This year in La Selva, our class did not spot any caiman or any other animals from the alligatoridae family. Melanie, a student from Providence studying abroad in Costa Rica, also stated that she hadn’t seen any caiman at the station since arriving a few months earlier. On our class boat trip we saw a caiman sticking part of its head, including eyeballs, out of the water. We were not able to see any caiman on our mangrove boat trip, although the local tour guide said that they were frequent seen there due to the availability of food. In Cahuita, there was a national park which had a “caiman habitat”. No Caiman were seen here. I believe this shortage of sightings could be due to the dry La Nina weather that has been affecting the tropics. The caiman can easily overheat, and will try to stay out of the humid weather that we experienced in La Selva.




References:
[1] – Maroni, Boris et al. (2008) Feeding Behavior of Two Sympatric Caiman Species, Melanosuchus niger and Caiman crocodilus, in the Brazilian Amazon. Journal of Herpetology, 42(4):768-772.

[2] – Silveira, Ronas Da 7& Magnusson, William E. (1999) Diets of Spectacled and Black Caiman in the Anavilhanas Archipelago, Central Amizonia, Brazil. Journal of Herpetology, 33(2):181-192.

[3] – Thornjarnarson, John B. (1994) Reproductive Ecology of the Spectacled Caiman (Caiman crocodilus) in the Venezuelan Llanos. Copeia 4: 907-919.

[4] - Da Silveira, Ronis (2010). Depredation by Jaguars on Caimans and Importance of Reptiles in the Diet of the Jaguar. Journal of Herpetology 44 (3).