The elusive and important freshwater turtles of Trinidad - reptilenesia
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| One of three native freshwater turtles on Trinidad: Gibba turtle (Mesoclemmys gibba) Photo by Renoir Auguste. |
Trinidad and Tobago are well known for the nesting marine turtles along the coasts. There have been numerous conservation efforts to highlight their importance thanks to local community groups, and international bodies. Typically, when a local person thinks of 'turtle' the Leatherback (Dermochelys coriacea) might usually come to mind more often than any other. However, Trinidad has three native freshwater species of turtles.
The first of the three native species is perhaps currently the most commonly encountered: The Galap or painted wood turtle (Rhinoclemmys punctularia) from the family Geomyididae. This family is the most species rich family of turtles globally with about 75 species recorded. They are represented with species across Europe, Asia, Africa and Central and South America. The Galap is the sole species from the family here. Individuals grow to an average size of about 20 cm. They can be identified by having red blotches on the crown of their head, yellow reticulations near the ear, and yellow or red spotted scales on the forelimbs. The Galap appears to be mainly found in south Trinidad with populations north centrally as well. Their habitat mainly consists of ponds or streams in forests, and can also be found at road side ditches. They are omnivores, and are known to act as seed disperses as they feed on fruits thus contributing to plant growth which benefits plants, other animals, and humans.
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| Galap (Rhinoclemmys punctularia) feeding on fruit in south Trinidad. Photo by Renoir Auguste |
The second of the three native freshwater turtles is the scorpion mud turtle (Kinosternon scorpioides) from the family Kinosternidae. This family has 25 species and are restricted to the western hemisphere. The scorpion mud turtle is the sole species on Trinidad currently, although subfossil remains hints at another species once being here. They grow to about 27 cm. The turtle can be identified by their domed carapace (shell) which varies from light brown to olive, with a brown-yellow head. They appear to be distributed across the south and northern basins of Trinidad; similar to the Galap. They may be found in temporary or permanent freshwater habitats, roadside ditches, and stream impoundments surrounded by forests. Although it may be relatively common, they are not always commonly seen and this may be because they bury themselves in the bottom of the pond or stream where they reside when it dries up, or are almost always under water when wet. Like the other two species they are nocturnal but may be active during the day. They are predominantly carnivores feeding on insects, molluscs, crustaceans, fish, frogs, worms, and mammals, but will consume algae and plant matter, including fruits thus also making them potential seed disperses.
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| Scorpion mud turtle (Kinosternon scorpioides) from central Trinidad. Photo by Rainer Deo |
The third native freshwater turtle species is perhaps the rarest on the island and rarely encountered: the Gibba turtle or side neck turtle (Mesoclemmys gibba) from the family Chelidae. There are about 53 species restricted to Central and South America. They are able to move their necks sideways into the shell (hence the common name). All are highly aquatic with the capacity to stay submerged for long periods of time. The Gibba turtle grows to about 30 cm. They can be identified by having a wide and flattened head with two barbles on the chin, dark brown or black carapace or shell and extensive webbing in the feet. Very little is known about this species locally. Previous literature suggests it is an uncommon lowland species. A survey published in 2010 found that they were restricted to the South Oropouche catchment based on anecdotal evidence from locals. However, as of 2018, individuals have been spotted by myself not far from the Aripo Savannas Scientific Reserve which is designated an Environmentally Sensitive Area in Trinidad. Like the other two species, they prefer areas with stagnant waters in forests, however with closed canopy. This suggests they would be susceptible and sensitive to habitat alteration. They are also nocturnal and are omnivores: also feeding on fruits like the other two species.
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| Gibba turtle (Mesoclemmys gibba) from northern Trinidad. Photo by Renoir Auguste |
Given the high precedent to marine turtle conservation, these three freshwater turtles should also be considered for priority conservation in Trinidad. They are an important component of the local fauna and ecosystems because of their seed dispersing capabilities and varied diet. They also comprise an important component of freshwater ecosystems. Greater effort towards learning more about their ecology is needed, which would not only benefit the local population of turtles but the freshwater ecosystems where they reside, other wildlife, and people.
Murphy, J.C., Downie, J.R., Smith, J.M., Livingstone, S.R., Mohammed, R.S., Auguste, R.J., Lehtinen, R.M., Eyre, M., Sewlal, J.N., Noriega, N., Casper, G.S., Anton, T., Thomas, R.A., Rutherford, M.G., Braswell, A.L., and Jowers, M.J. 2018. A field guide to the amphibians and reptiles of Trinidad and Tobago. Trinidad and Tobago Field Naturalists’ Club. 336 pp.
Murphy, J.C., Downie, J.R., Smith, J.M., Livingstone, S.R., Mohammed, R.S., Auguste, R.J., Lehtinen, R.M., Eyre, M., Sewlal, J.N., Noriega, N., Casper, G.S., Anton, T., Thomas, R.A., Rutherford, M.G., Braswell, A.L., and Jowers, M.J. 2018. A field guide to the amphibians and reptiles of Trinidad and Tobago. Trinidad and Tobago Field Naturalists’ Club. 336 pp.
