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.
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.
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.
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.
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