New Publication

 

Conservation status of the Dwarf Marsupial Frog in Trinidad, Tobago, & Venezuela

 

Drawf marsupial frog (Flectonotus fitzgeraldi) female with eggs on back. Photo by Renoir Auguste

The dwarf marsupial frog is a small frog found in Trinidad, Tobago and Venezuela. It is a forest specialist species usually found in vegetation with closed canopy and near streams. They are called Marsupial frogs because the females carry their eggs in a pouch on their back, like the marsupials from Australia (that have the pouch by their belly). 

The International Union for the Conservation of Nature (IUCN) in 2004 regarded the dwarf marsupial frog as endangered. That status remained unchanged for 16 years. However, a team of researchers from Trinidad, Venezuela, UK, EU, & US compiled biological data done on the species in its respective range which provided important information for its conservation. Based on the surveys, the frog was found to be widely distributed across Trinidad, northeast Tobago and northeastern Venezuela. As such, the group, lead by professor Roger Downie from Glasgow University suggested that the conservation status be downgraded from Endangered to Least Concern. 

This is an important milestone for this species based on the updated information provided by this study. However, further studies on number of individuals in its range are needed to continuously monitor the species, as it can potentially revert to its more threatened status because of climate change, habitat alteration and diseases because of its very specific habitat requirements.

Reference: 

Smith, J., Jowers, M.J., Auguste, R.J., Hoskisson, P., Beyts, C., Muir, G., Greener, M.S., Thornham, D., Byrne, I., Lehtinen, R., Eyre, M., Rutherford, M.G., Murphy, J.C.,  De Freitas, M., Rivas G.A., and Downie, J.R. 2021. The distribution and conservation status of the dwarf marsupial frog (Flectonotus fitzgeraldi) in Trinidad, Tobago and Venezuela. Amphibian and Reptile Conservation 15(1): 36-56.

Link to paper here: http://amphibian-reptile-conservation.org/pdfs/Volume/Vol_15_no_1/ARC_15_1_[General_Section]_36-56_e273.pdf

Rutherford's Vine Snake From Trinidad Specializes In Eating Lizards

Photo of Rutherford's Vine Snake (Oxybelis rutherfordi) predating on a Beachrunner lizard (Cnemidophorus lemniscatus). Photo by Marie-Elise Maingot. Rutherford's Vine Snake (Oxybelis rutherfordi) or as locals refer to them "Horsewhip", was a recently (re)described species of snake found in Trinidad and Tobago and northern South America. Populations found here were previously thought to be the same as the widespread Brown Vine Snake (Oxybelis aeneus), but research showed they are two distinct species. In Trinidad and Tobago, Rutherford's Vine Snake is widespread, found in forests, coastlines, and even in residential gardens. Data on the diet of this species, and snakes in general are poorly known. Filling this gap is important as it allows us to learn more about how these animals use their environment and interact with it. A newly published Natural History Note was published in the journal "Phyllomedusa" and it documents five lizard species that Rutherford's Vine Snake feeds on. Observations were documented by keen citizen scientists from across Trinidad that luckily were able to photograph the snake predating on a lizard. These observations can be very rare to observe and thus highlighting them adds to biological data. To read more about the five lizard species that the Rutherford's Vine Snake feeds on, see this link to a pdf describing the events that took place here in Trinidad. If you are a passionate photographer, or generally enjoy nature, do not hesitate to share your photos of reptiles and amphibians with us! You can reach out to us on Instagram on the page "Herp.Research.TT", or email the Trinidad and Tobago Field Naturalists' Club asking for the Herpetology Group Leader.

Boa constrictor feeds on a variety of prey, including doves

Boa constrictor predating on a Ruddy ground dove. Photos provided by Adam Fifi. || The Boa constrictor, locally known as Macajuel or red-tailed boa, is a common snake found across both Trinidad and Tobago (Murphy et al. 2018). This large, non-venomous snake is a top predator in ecosystems where they reside and help maintain food web balance. Boa constrictors feed on a variety of other animals, including small mammals such as rodent pests, lizards, and sometimes birds. Indeed, although Boa constrictors may be found mostly on the ground, they do sometimes climb up trees, which enables them the ability to prey on birds. An example can be seen in the Field Guide to the Amphibians and Reptiles of Trinidad and Tobago where an individual was observed predating on a crested oropendola, photographed by Edward Barrow. A Living World article by Hayes and Gabriel (2019) also highlights another common bird (kiskadee) that the Boa constrictor feeds on. However, an additional bird prey includes the very widespread and common Ruddy ground dove. This is perhaps the most easily seen and common bird in urban gardens, near residential areas. Thus, it may not be too surprising that the Boa constrictor also feeds on them. This natural history observation is the first reported documentation of this particular prey species, and was published in the international journal Herpetological Review in March 2021. This event took place on Gasparee island, and no doubt Boa constrictors continue to predate on other small animals there, and across Trinidad and Tobago. || References Murphy, J.C., Downie, J.R.,...Auguste, R.J. 2018. A field guide to the amphibians and reptiles of Trinidad and Tobago. Trinidad and Tobago Field Naturalists' Club. 336 pp. || Hayes, F.E., and Gabriel, R.L. 2019. Predation by a Boa Constrictor (Boa constrictor) on a Great Kiskadee (Pitangus sulphuratus) in Trinidad, W.I. Living World 2019: 47-48. || Auguste, R.J. and Fifi, A. 2021. Boa constrictor diet. Herpetological Review 52:146-147.

A new species of frog re-described from Trinidad

Photo: (Elachistocleis nigrogularis sp nov). Photograph by Renoir Auguste. Every year, new species are being described for the first time, adding to the list of wildlife on Earth. In addition to new species being described (and discovered for the first time), some species are being re-described as new, distinct organisms. These new re-descriptions are based on a closer inspection of the organisms' DNA, morphology, and other biological characteristics. Over the past decade, new species have been re-described from Trinidad and Tobago. And now there is another. Narrow mouth frogs (in the genus Elachistocleis) are found across South America, and Trinidad. One of these narrow mouth Elachistocleis frogs was recently described as a new species, distinct from others in the same genus. The scientific name is Elachistocleis nigrogularis, and it got its name (nigrogularis) referring to its black throat that both the males and females have, a distinguishing feature compared to its cousins. This frog (seen in the photograph above), is active mainly at the start of the rainy season where it can be heard calling, which sounds like a long whistle-like call that can be heard just before heavy rains. One may have heard them while passing by the Aripo Savannas, Arena Forest, or Bush Bush Wildlife Sanctuary in Trinidad. These frogs feed on ants and termites and are important parts of the environment. They are the latest new species to be described from Trinidad and Tobago. They will not be the last! To read the scientific paper, here is the DOI link: 10.1007/s13127-021-00487-y or you can contact the Herpetology Group leader of the Trinidad and Tobago Field Naturalists' Club (ttfnc.org).

A new lizard recorded for Trinidad & the importance of Citizen Science

 

Mourning gecko (Lepidodactylus lugubris). Photo by Adam Fifi

Among exotic reptiles, lizards are the most abundant group introduced to new regions, and even to different countries. One particular group of lizards seem to drift far away from their native countries - Geckoes! No doubt, human facilitation through movement of goods and people have aided in the distribution of animals, including lizards. 

Trinidad and Tobago has had at least a half a dozen lizards introduced to the country. Most of these have been Anolis lizards (at least 6 species). However geckoes are about halfway behind with at least 3 new species to the country. One of these is the mourning gecko (Lepidodactylus lugubris). The gecko was first reported on the citizen science application iNaturalist, and have subsequently been found by others across the country. This short natural history note documents their distribution in the scientific literature for the first time, and commends the efforts of persons that took photos and uploaded to iNaturalist. 

If you don't use or are familiar with iNaturalist, it is highly recommended. Who knows, maybe you may photograph an animal in the country and it turns out to be a new record for the country!

Reference: 

Auguste, R.J., Fifi, A. 2020. Additional record of the invasive mourning gecko Lepidodactylus lugubris (Duméril and Bibron, 1836) from Trinidad and Tobago, with comments on citizen science observations. Herpetology Notes 13: 1111-1112 (link to pdf of paper here)

Cryptic diversity in the black-headed snake from Trinidad & Tobago?

Black-headed snake (Tantilla melanocephala). Photo by Renoir Auguste

Previous studies have shown that some widespread species are in fact cryptic species - or species that resemble each other superficially, but are actually two or more different species.  This aspect can have serious implications towards conservation of species, as each species has their own unique traits. Thus, studies examining the cryptic diversity in species is important for conservation management.

The black-headed snake (Tantilla melanocephala) is a widespread snake found across Central, and South America. It is also found on Trinidad and Tobago and southern Lesser Antilles in the Caribbean. A recent study examined the genetic materials and morphology of specimens from T&T and compared them to northern South American individuals. It was found that the populations on T&T are related to those on Venezuela - which is a common trait among many other species. Further studies are needed, but this one sets a landmark foundation to examine other individuals from across its range.

Reference: 

Jowers, M.J., Rivas, G.A., Jadin, R.C., Braswell, A.L., Auguste, R.J., Borzée, A., and Murphy, J.C. 2020. Unravelling the species diversity of a cryptozoic snake, Tantilla melanocephala, in its northern distribution with emphasis to the colonization of the Lesser Antilles. Amphibian and Reptile Conservation 14(3): 206-217 (pdf here)

Conservation Status of Trinidad & Tobago Frogs updated on IUCN 2020 v3

Tobago Glass Frog (Hyalinobatrachium orientale tobagoense). Photo by Renoir Auguste

 The International Union for the Conservation of Nature (IUCN) is a widely, credited source of species' conservation status across the world. Thousands of species have been assessed, many more (hundreds of) thousands are yet to. Trinidad and Tobago (currently) has 35 recognized species of amphibians, all Anurans or frogs and toads. All 35 species have been assessed on IUCN and their updated conservation status came out in the 2020 version 3 update. Local and international experts were consulted to provide information to assess each species.

From the new update, 30/35 (85%) species are listed as Least Concern, or not currently threatened with immediate extinction. One species is listed as Endangered, three as Vulnerable, and one Data Deficient. 

The Endangered species is the golden tree frog (Phytotriades auratus). This species was previously listed as a Trinidad endemic frog and Critically Endangered, but the IUCN Amphibian SSC Group believes that its discovery in Venezuela warrants a lower threat level because of its wider distribution, despite its very restricted microhabitat.

The three Vulnerable species are all Tobago endemics: The Tobago stream frog (Mannophryne olmonae), Charlotteville litter frog (Pristimantis charlottevillensis), and Tobago glass frog (featured in photo above). The Vulnerable threat level was assigned given their restricted area of occupancy.

The one frog listed as Data Deficient, is the Tobago endemic Turpin's litter frog (Pristimantis turpinorum). Since its formal description in 2001, very little information is known about its biology, likely because of its very secretive habits, with too few specimens observed. This species is a prime example where research is needed to help provide much needed information about updating its conservation status, and prohibiting its potential extinction. 

Turpin's litter frog (Pristimantis turpinorum). Photo by Renoir Auguste

More work needs to be done, but at least provisional efforts have contributed to us knowing more about these important animals, some of which can be found nowhere else in the world.

Links to some of the species' IUCN status:

https://www.iucnredlist.org/

Citizen Monitoring of Green Iguanas in Trinidad and Tobago

Green iguana (Iguana iguana). Photo by Renoir Auguste

 The green iguana (Iguana iguana) is widely distributed (ubiquitous) across Trinidad and Tobago. It can be found in forests as well as in urban gardens and parks. In Trinidad and Tobago they are hunted for their meat. Although the green iguana is perhaps very abundance currently, there have been no targeted efforts to document its distribution and abundance locally. This perhaps may be because of different reasons, with lack of funding being one of them. 

During the restrictions enforced by safety precautions for managing covid-19 spread, a call was made in April 2020 by the Trinidad and Tobago Field Naturalists' Club Herpetology Group Leader to Club members and members of the public across urban areas in Trinidad to document green iguanas from their backyard. Persons were reached out mainly using social media. During the very short period, over a hundred iguanas were reported from across urban areas in Trinidad which was published in the international journal Reptiles and Amphibians. This rapid assessment illustrates how citizen science can contribute to ecological data in a short time frame with limited expenses. Hopefully, the data can be used to better manage exploited green iguanas in urban areas in Trinidad, and provide a baseline for future studies on the exploited reptile.

Reference: 

Auguste, R.J. 2020. Using citizen science to rapidly determine the distribution of exploited green iguanas (Iguana iguana) across urban Trinidad and Tobago.  Reptiles & Amphibians 27(3): 419-421.

Link to paper here:

https://journals.ku.edu/reptilesandamphibians/article/view/14859

Peptides in two Trinidadian frogs reveal antimicrobial resistance

 

Barbour's thin-toed frog (Leptodactylus insularum). Photo by Renoir Auguste

Frogs are vitally important to ecosystems, and to people. Their importance in ecosystems stems from the roles they play acting as predator and prey to a variety of animals. Their ecological importance also benefits people, as frogs prey on insects, including pests to crops and mosquitoes. However frogs also play an important role in medicinal values. In particular, the peptides in frog skin secretions have been used to treat diseases, for example diabetes. Trinidad and Tobago has at least 35 species of frogs (amphibians). Thus far, at least two frog species have shown to have peptides useful for medicine, including the paradoxical frog (Pseudis paradoxa), and the Trinidad leaf-nesting frog (Phyllomedusa trinitatis). Now, two more species can be added to the list. A recent published study by Barran and colleagues (2020) found antimicrobial resistant properties in two species. These are the Trinidadian thin-toed frog (Leptodactylus nesiotus), and Barbour's thin-toed frog (Leptodactylus insularum). Barran and colleagues' study further exemplifies the importance of conserving frogs in Trinidad and Tobago, and all citizens should do their part by learning more about them, and conserving them for generations to come. Citation: Barran, G.; Kolodziejek, J.; Coquet, L.; Leprince, J.; Jouenne, T.; Nowotny, N.; Conlon, J.M.; Mechkarska, M. Peptidomic Analysis of Skin Secretions of the Caribbean Frogs Leptodactylus insularum and Leptodactylus nesiotus (Leptodactylidae) Identifies an Ocellatin with Broad Spectrum Antimicrobial Activity. Antibiotics 2020, 9, 718. Link to paper here: pdf

Cryptic diversity, & a unique reproductive mode in a Neotropical water snake from Trinidad

A recent published study by Murphy and colleagues (2020) suggest that the number of water snakes in the genus Helicops has increased from 19 to 20 species based on morphology. Trinidad has one species (currently) in that genus - Helicops angulatus, known commonly as the brown-banded water snake, or to some locals as the "water mapepire" (seen in the photograph above by Renoir Auguste), because of its superficial resemblance to the Bothrops viper "Mapepire Balsain". This snake though, is not just another snake. It is believed to have a unique reproductive mode whereby females presumably lay eggs, like many other reptiles, but also gives birth to live young! This is sometimes referred to as facultative (viviparous) reproduction as they are able to do both. It is not certain as to what brings about the different choice (or lack thereof) in reproductive mode. Perhaps it is environmental related. However, the importance of conserving this unusual snake population, and its habitat is of paramount importance as we may be able to learn more about the evolution of this species, Squamates: lizards and snakes, and the potential benefits they may have to improving our knowledge of biodiversity conservation. Citation: Murphy JC, Muñoz-Mérida A, Auguste RJ, Lasso-Alcalá O, Rivas GA, Jowers MJ. 2020. Evidence for cryptic diversity in the Neotropical water snake, Helicops angulatus (Linnaeus, 1758) (Dipsadidae, Hydropsini), with comments on its ecology, facultative reproductive mode, and conservation. Amphibian & Reptile Conservation 14(3) [Taxonomy Section]: 138–155 (e261). Link to paper here: pdf

Brown vine snake (Horsewhip) from Trinidad and Tobago renamed after Mike Rutherford

 

The brown vine snake from Trinidad and Tobago locally known as Horsewhip has recently been re-described as a new species based on genetic and morphological data, compared to other specimens from across the Americas. The research was lead by Jadin and colleagues and published this year. The snake's scientific name is Oxybelis rutherfordi, or commonly Rutherford's vine snake.

The species has been named in honour of Mike Rutherford, who was the former Curator of the University of the West Indies Zoology Museum, for his contributions to Zoology and Natural History in Trinidad and Tobago. Persons from Trinidad and Tobago that have participated in the annual Bioblitz or with the Trinidad and Tobago Field Naturalists' Club will be familiar with Mike. Congrats, Mike!

No doubt, new species of reptiles and amphibians will continue to be described in the country, which makes for exciting opportunities for young naturalists to get involved and passionate about wildlife. 

Reference: 

Jadin et al. 2020. Not withering on the evolutionary vine: systematic revision of the Brown Vine Snake (Reptilia: Squamata: Oxybelis) from its northern distribution. Organisms Diversity & Evolution