Yacare caiman

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Yacare caiman
Temporal range: Late MiocenePresent, 11.6–0  Ma [1]
Yacare Caiman (Caiman yacare) (28742110492).jpg
Mato Grosso, Brazil
CITES Appendix II (CITES) [3]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauromorpha
Clade: Archosauriformes
Order: Crocodilia
Family: Alligatoridae
Subfamily: Caimaninae
Clade: Jacarea
Genus: Caiman
Species:
C. yacare
Binomial name
Caiman yacare
Daudin, 1802
The range of the Yacare caiman.png
Range (black)
Synonyms [4]
  • Crocodilus yacare
    Daudin, 1802
  • Caiman yacare
    Schmidt, 1928
  • Jacaretinga crocodilus yacare
    F. Werner, 1933
  • Caiman crocodilus yacare
    L. Müller & Hellmich, 1936
  • Caiman yacare
    Cei, 1993

The yacare caiman (Caiman yacare), also known commonly as the jacare caiman, Paraguayan caiman, piranha caiman, red caiman, [5] and southern spectacled caiman, [6] is a species of caiman, a crocodilian in the family Alligatoridae. The species is endemic to Argentina, Bolivia, Brazil, and Paraguay. Brown in color and covered with dark blotches, males grow to a total length (including tail) of 2–3 m (6 ft 7 in – 9 ft 10 in) and weigh around 40–50 kg (88–110 lb); while females grow to 1.4 m (4 ft 7 in) long and about 15–20 kg (33–44 lb). [7] Typical habitats of this caiman include lakes, rivers, and wetlands. Its diet primarily consists of aquatic animals, such as snails, and occasionally land vertebrates. Mating occurs in the rainy season and eggs hatch in March, with young fending for themselves as soon as they hatch. The yacare caiman was hunted heavily for its skin to use for leather in the 1980s, which caused its population to decrease significantly. However, trading restrictions placed since have caused its population to increase. Its population in the Pantanal is about 10 million, and it is listed as least concern on the IUCN Red List.

Contents

Taxonomy

François Marie Daudin originally described the yacare caiman in 1802 as Crocodilus yacare. [8] :7 Its specific name, yacare, comes from the word jacaré, which means "alligator" in Old Tupi and then assimilated into Portuguese. [6]

The yacare caiman is one of three extant (living) species of the genus Caiman , the other two being the Spectacled caiman (Caiman crocodilus) and the Broad-snouted caiman (Caiman latirostris). There are also several extinct fossil species in the genus Caiman , possibly up to eight species. The yacare caiman is a member of the caiman subfamily Caimaninae, and is one of six living species of caiman.

As of 2010, the exact relationship between the yacare caiman and related species is unclear and complicated. There have been attempts to analyze this relationship, but these have not produced definite conclusions. It is sometimes considered a subspecies of the spectacled caiman (Caiman crocodilus), which would make its scientific name Caiman crocodilus yacare. These two species are the same morphologically, but are considered separate species due to their geographical differences. [9] :24 Its relationship to the spectacled caiman and the other extant caimans can be shown in the cladogram below, based on molecular DNA-based phylogenetic studies: [10]

Alligatoridae
Caimaninae

Paleosuchus palpebrosus Cuvier's dwarf caiman

Paleosuchus trigonatus Schneider's dwarf caiman

Jacarea

Caiman crocodilus Spectacled caiman

Caiman yacareYacare caiman

Caiman latirostris Broad-snouted caiman

Melanosuchus niger Black caiman

Alligatorinae

Alligator sinensis Chinese alligator

Alligator mississippiensis American alligator

Description

C. yacare is a medium-sized caiman, brown in color. [5] Male specimens grow to 2–3 m (6 ft 7 in – 9 ft 10 in) in total length (including tail) and up to 58 kg (128 lb) in weight. Females are much smaller, with an adult total length of 1.4 m (4 ft 7 in) and weight of 14–23 kg (31–51 lb). [11] [8] :7 The average snout–vent length (SVL) of hatchlings is 12.49 cm (4.92 in) for females and 12.84 cm (5.06 in) for males. [7] National Geographic has described young individuals as "look(ing) like nothing more than tiny, windblown seeds floating amid the rushes at the edge of a lagoon in Brazil's remote interior." [12] Based on a study of the growth of multiple specimens in the Pantanal from 1987 to 2013, both sexes are about 50 cm (20 in) SVL at age five. By age 15, they have mostly finished growth, with females being about 80 cm (31 in) SVL and males over 100 cm (39 in) SVL. The study also showed that individuals have significant variation in their growth rates. [7]

Dark marks are distributed across the body; most noticeably, its lower jaw is covered with three to five blotches. It has a smooth snout, which is medium in length and broad. It has lumps on its eyelids and a curved ridge between its eyes. [8] :7 It has osteoderms on its scales, a feature also present in the spectacled caiman. It has an average of 74 teeth, with 5 pre-maxillary, 14–15 maxillary, and 17–21 mandibular. [6] Some of the teeth on its lower jaw can poke through holes in its upper jaw. [8] :7 This feature makes its teeth more prominent and has been compared to piranhas, which has established the common name "piranha caiman". [5]

Ecology

The yacare caiman is ecologically similar to the spectacled caiman. [9] :23 It lives in semi-aquatic habitats, including lakes, rivers, and wetlands, [6] but is able to adapt to a variety of habitats. Individuals sometimes move to different locations in groups if their habitat is disturbed. [9] :24 The species' diet consists of aquatic animals, such as snails and fish, and occasionally snakes. [6] It has also been known to eat capybaras. [12] When hunting for snails, this caiman looks within vegetation floating in water and uses its jaws to break the shells of the snails. [5] In July 1986, the stomach of a specimen in Bolivia was observed to be full of mud, along with small parts of eggshells that likely belonged to a caiman. In general, crocodilians can eat the eggshells of their own young subsequent to the young hatching. [13]

Breeding usually occurs in December–February, in the middle of the rainy season. [6] Nests are constructed by the females, built in a mound shape using mud and rotting vegetation. [5] The species can lay as many as 44 eggs, but it most commonly lays 22–35, with the exact number often depending on the habitat type. [9] :24 It often exhibits multiple paternity, more so than several other crocodilian species. [14] Females usually protect nests during incubation, but do so less when the human hunting pressure is high, ultimately causing a lower hatching success rate. [9] :24 Eggs hatch in March. [6] Young exhibit precociality, receiving very little help from their parents and having to care for themselves. [5] They hide in grasses in the daytime, as herons and storks can eat young caimans. [12] Females become sexually mature at age 10–15. [7] Similar species of the yacare caiman live to about age 50, which has been used as an estimate for this caiman's lifespan, but its exact lifespan is unknown. [5]

Distribution and conservation

Group of Yacare Caiman in Mato Grosso,Brazil Yacare Caimans (Caiman yacare) - Flickr - berniedup.jpg
Group of Yacare Caiman in Mato Grosso,Brazil

The range of the yacare caiman includes Argentina (north), Bolivia, Brazil (south), and Paraguay. [11] It is one of three species of genus Caiman in South America, the others being the broad-snouted caiman (C. latirostris) and the spectacled caiman (C. crocodilus), with more easterly and northerly ranges, respectively. The yacare caiman is one of the most common species on its continent. [14]

In the 1980s, the species was "heading for oblivion" due to frequently being hunted for its skin; [12] hunters often went to water holes containing many yacare caimans and shot large numbers of them. They utilized the skin for leather and left the other parts of the carcasses at the water holes. [12] Although the species is covered with bony osteoderms, which had previously made it uncommon to be hunted for leather, it has some less bony spots which can be used for leather. [8] :582 This practice caused the caiman's population to drop by the millions. In 1992, a ban was issued in Brazil that prohibited the trading of crocodilian skins. This resulted in a significant increase in its population, with about 10 million specimens living in the Pantanal alone as of 2013. [12] Current threats of the yacare caiman include deforestation, tourism, construction of dams and seaports, and illegal hunting. [12] The species reproduces quickly, which makes it less susceptible to hunting pressure. [6]

The IUCN Red List designated the yacare caiman a species of least concern in 1996. [2] It is listed as threatened by the United States Fish and Wildlife Service as of June 5, 2000, after having been listed as endangered since June 2, 1970. [15] As of 2010, it is listed as an Appendix II species by the Convention on International Trade in Endangered Species of Wild Fauna and Flora. [9] :23

Related Research Articles

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The family Alligatoridae of crocodylians includes alligators, caimans and their extinct relatives.

<span class="mw-page-title-main">Crocodilia</span> Order of mostly large, predatory, semiaquatic reptiles

Crocodilia is an order of mostly large, predatory, semiaquatic reptiles known as crocodilians. They first appeared 94 million years ago in the Late Cretaceous period and are the closest living relatives of birds, as the two groups are the only known survivors of the Archosauria. Members of the order's total group, the clade Pseudosuchia, appeared about 250 million years ago in the Early Triassic period, and diversified during the Mesozoic era. The order Crocodilia includes the true crocodiles, the alligators and caimans, and the gharial and false gharial. Although the term crocodiles is sometimes used to refer to all of these, crocodilians is a less ambiguous vernacular term for members of this group.

<i>Caiman</i> (genus) Genus of reptiles

Caiman is a genus of caimans within the alligatorid subfamily Caimaninae. They inhabit Central and South America. They are relatively small sized crocodilians, with all species reaching lengths of only a couple of meters and weighing 6 to 40 kg on average.

<span class="mw-page-title-main">Pantanal</span> Tropical wetland in Brazil, Bolivia and Paraguay

The Pantanal is a natural region encompassing the world's largest tropical wetland area, and the world's largest flooded grasslands. It is located mostly within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and portions of Bolivia and Paraguay. It sprawls over an area estimated at between 140,000 and 195,000 km2. Various subregional ecosystems exist, each with distinct hydrological, geological and ecological characteristics; up to 12 of them have been defined.

<span class="mw-page-title-main">Black caiman</span> Largest extant species of caiman

The black caiman is a crocodilian reptile endemic to South America. With a maximum length of around 5 to 6 m and a mass of over 450 kg (1,000 lb), it is the largest living species of the family Alligatoridae, and the third-largest crocodilian in the Neotropical realm. True to its common and scientific names, the black caiman has a dark greenish-black coloration as an adult. In some individuals, the pigmentation can appear almost jet-black. It has grey to brown banding on the lower jaw; juveniles have a more vibrant coloration compared to adults, with prominent white-pale yellow banding on the flanks that remains present well into adulthood. The banding on young animals helps with camouflage by breaking up their body outline, on land or in water, in an effort to avoid predation. The morphology is quite different from other caimans but the bony ridge that occurs in other caimans is present. The head is large and heavy, an advantage in catching larger prey. Like all crocodilians, caimans are long, squat creatures, with big jaws, long tails and short legs. They have thick, scaled skin, and their eyes and noses are located on the tops of their heads. This enables them to see and breathe while the rest of their bodies are underwater.

<span class="mw-page-title-main">Nile crocodile</span> Reptile of Africa

The Nile crocodile is a large crocodilian native to freshwater habitats in Africa, where it is present in 26 countries. It is widely distributed in sub-Saharan Africa, occurring mostly in the eastern, southern, and central regions of the continent, and lives in different types of aquatic environments such as lakes, rivers, swamps, and marshlands. Although capable of living in saline environments, this species is rarely found in saltwater, but occasionally inhabits deltas and brackish lakes. The range of this species once stretched northward throughout the Nile River, as far north as the Nile Delta. Lake Rudolf in Kenya has one of the largest undisturbed populations of Nile crocodiles. Generally, the adult male Nile crocodile is between 3.5 and 5 m in length and weighs 225 to 750 kg. However, specimens exceeding 6.1 m (20 ft) in length and 1,000 kg (2,200 lb) in weight have been recorded. It is the largest freshwater predator in Africa, and may be considered the second-largest extant reptile in the world, after the saltwater crocodile. Size is sexually dimorphic, with females usually about 30% smaller than males. The crocodile has thick, scaly, heavily armoured skin.

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<span class="mw-page-title-main">Broad-snouted caiman</span> Species of reptile

The broad-snouted caiman is a crocodilian in the family Alligatoridae found in eastern and central South America, including southeastern Brazil, northern Argentina, Uruguay, Paraguay, and Bolivia. It is the second largest caiman and the third largest alligatorid. It is found mostly in freshwater marshes, swamps, and mangroves, usually in still or very slow-moving waters. It will often use man-made cow ponds.

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<span class="mw-page-title-main">Cuvier's dwarf caiman</span> Species of reptile

Cuvier's dwarf caiman is a small crocodilian in the alligator family from northern and central South America. It is found in Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Paraguay, Peru, Suriname, Trinidad and Venezuela. It lives in riverine forests, flooded forests near lakes, and near fast-flowing rivers and streams. It can traverse dry land to reach temporary pools and tolerates colder water than other species of caimans. Other common names for this species include the musky caiman, the dwarf caiman, Cuvier's caiman, and the smooth-fronted caiman. It is sometimes kept in captivity as a pet and may be referred to as the wedge-head caiman by the pet trade community.

<span class="mw-page-title-main">Smooth-fronted caiman</span> Species of reptile

The smooth-fronted caiman, also known as Schneider's dwarf caiman or Schneider's smooth-fronted caiman, is a crocodilian from South America, where it is native to the Amazon and Orinoco Basins. It is the second-smallest species of the family Alligatoridae, the smallest being Cuvier's dwarf caiman, also from tropical South America and in the same genus. An adult typically grows to around 1.2 to 1.6 m in length and weighs between 9 and 20 kg. Exceptionally large males can reach as much as 2.3 m (7.5 ft) in length and 36 kg (79 lb) in weight.

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<i>Paleosuchus</i> Genus of reptiles

Paleosuchus is a South American genus of reptiles in the subfamily Caimaninae of the family Alligatoridae. They are the smallest members of the order Crocodilia in the Americas.

<span class="mw-page-title-main">Spectacled caiman</span> Species of crocodilian native to the Neotropics

The spectacled caiman, 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 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.

<i>Mourasuchus</i> Extinct genus of reptiles

Mourasuchus is an extinct genus of giant, aberrant caiman from the Miocene of South America. Its skull has been described as duck-like, being broad, flat, and very elongate, superficially resembling Stomatosuchus from the Late Cretaceous.

<span class="mw-page-title-main">Caiman</span> Subfamily of reptiles

A caiman is an alligatorid belonging to the subfamily Caimaninae, one of two primary lineages within the Alligatoridae family, the other being alligators. Caimans are native to Central and South America and inhabit marshes, swamps, lakes, and mangrove rivers. They have scaly skin and live a fairly nocturnal existence. They are relatively small-sized crocodilians with an average maximum weight of 6 to 40 kg depending on species, with the exception of the black caiman, which can grow more than 4 m (13 ft) in length and weigh in excess of 1,000 kg. The black caiman is the largest caiman species in the world and is found in the slow-moving rivers and lakes that surround the Amazon basin. The smallest species is the Cuvier's dwarf caiman, which grows to 1.2 to 1.5 m long. There are six different species of caiman found throughout the watery jungle habitats of Central and Southern America. The average length for most of the other caiman species is about 2 to 2.5 m long.

<span class="mw-page-title-main">Jacarea</span> Clade of reptiles

Jacarea is a clade of caimans within the subfamily Caimaninae. Jacarea was first named by Norell in 1988 to include the extant species within the genera Caiman and Melanosuchus, while excluding the dwarf caiman genus Paleosuchus. In 1999, Brochu formally cladistically defined Jacarea as the last common ancestor of Caiman latirosris, Caiman crocodilus, Caiman yacare, Melanosuchus niger, and all its descendants. Molecular DNA phylogenetic studies recover Paleosuchus as outside of Jacarea, although morphological studies are inconsistent.

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Caiman brevirostris is an extinct species of caiman that lived during the Late Miocene, around 11.6 million years ago, to the end of the Miocene 5.3 million years ago in Acre and Amazonas, Brazil as well as Urumaco, Venezuela. Several specimens have been referred to the species, but only 3 of them are confidently placed in the species. C. brevirostris was originally named in 1987 on the basis of a single, incomplete rostrum with an associated mandibular ramus that had been found in Acre, Brazil. C. brevirostris is very distinct among Caiman species and caimaninae overall in that it preserves a characteristically short and robust skull that bears blunt posterior teeth that were built to break down harder foods. This was an adaption for durophagy, likely to crush shells of mollusks and clams which were common in the wetlands that C. brevirostris resided in.

References

  1. Rio, Jonathan P.; Mannion, Philip D. (6 September 2021). "Phylogenetic analysis of a new morphological dataset elucidates the evolutionary history of Crocodylia and resolves the long-standing gharial problem". PeerJ . 9: e12094. doi: 10.7717/peerj.12094 . PMC   8428266 . PMID   34567843.
  2. 1 2 Campos, Z.; Llobet, A.; Magnusson, W.E.; Piña, C. (2020). "Caiman yacare". IUCN Red List of Threatened Species . 2020: e.T46586A3009881. doi: 10.2305/IUCN.UK.2020-3.RLTS.T46586A3009881.en . Retrieved 19 November 2021.
  3. "Appendices | CITES". cites.org. Retrieved 2022-01-14.
  4. Species Caiman yacare at The Reptile Database
  5. 1 2 3 4 5 6 7 "Yacare Caiman". Beardsley Zoo . Retrieved 28 February 2019.
  6. 1 2 3 4 5 6 7 8 Britton, Adam. "Yacare caiman (Caiman yacare)". Crocodilians: Natural History and Conservation. Retrieved 27 February 2019.
  7. 1 2 3 4 Campos, Zilca; Mourão, Guilherme; Coutinho, Marcos; Magnusson, William E. (February 28, 2014). "Growth of Caiman crocodilus yacare in the Brazilian Pantanal". PLOS One . 9 (2): e89363. doi: 10.1371/journal.pone.0089363 . PMC   3938444 . PMID   24586719.
  8. 1 2 3 4 5 Grigg, Gordon (January 15, 2015). Biology and Evolution of Crocodylians. CSIRO Publishing. ISBN   978-1486300679 . Retrieved 27 February 2019.
  9. 1 2 3 4 5 6 Campos, Z.; Llobet, A.; Piña, C. I.; Magnusson, W. E.; Manolis, C. S.; Stevenson, C. (2010). Crocodiles: Status Survey and Conservation Action Plan (PDF) (third ed.). Crocodile Specialist Group. pp. 23–28. Retrieved 27 February 2019.
  10. Bittencourt, Pedro Senna; Campos, Zilca; Muniz, Fabio de Lima; Marioni, Boris; Souza, Bruno Campos; Da Silveira, Ronis; de Thoisy, Benoit; Hrbek, Tomas; Farias, Izeni Pires (22 March 2019). "Evidence of cryptic lineages within a small South American crocodilian: the Schneider's dwarf caiman Paleosuchus trigonatus (Alligatoridae: Caimaninae)". PeerJ . 7: e6580. doi: 10.7717/peerj.6580 . PMC   6433001 . PMID   30931177.
  11. 1 2 "3.3 Caimans". Food and Agriculture Organization of the United Nations.
  12. 1 2 3 4 5 6 7 Smith, Roff (July 2013). "Brazil's Yacare Caiman — The Comeback Croc". National Geographic . Archived from the original on February 28, 2019. Retrieved 27 February 2019.
  13. King, F. Wayne; Godshalk, Robert (2003). "Mud, Root Balls, and Other Tasty Tidbits in Crocodilian Stomach". Florida Museum of Natural History . Retrieved 2 March 2019.
  14. 1 2 Ojeda, Guillermo N.; Amavet, Patricia C.; Rueda, Eva C.; Siroski, Pablo A.; Larriera, Alejandro (March 1, 2017). "Mating System of Caiman yacare (Reptilia: Alligatoridae) Described from Microsatellite Genotypes". Journal of Heredity . 108 (2): 135–141. doi: 10.1093/jhered/esw080 . PMID   28175334.
  15. Fish and Wildlife Service (May 4, 2000). "Endangered and Threatened Wildlife and Plants; Reclassification of Yacare Caiman in South America From Endangered to Threatened, and the Listing of Two Other Caiman Species as Threatened by Reason of Similarity of Appearance". Federal Register : 25867–25881. Retrieved 27 February 2019.

Further reading