Deadly fungus detected in the Endangered Golden Tree Frog

Golden Tree Frog (Phytotriades auratus) from Trinidad. Photo by Rick Lehtinen. ||| The golden tree frog is found in Trinidad and Venezuela. It is a species restricted to mountain tops, and lives almost entirely in bromeliads on trees. This frog species is currently considered endangered by the IUCN, and is threatened by climate change and habitat degradation. However, a recent publication by Lehtinen, Borowsky, Auguste, Kosowsky and Richards-Zawacki in Herpetological Review 54(1) 2023 reports that the deadly chytrid fungal pathogen (Bd) was detected in individuals from El Tucuche in Trinidad. The chytrid fungus has been responsible for amphibian declines and extinctions across the world. This is a worrying find for the endnagered golden tree frog, and warrants urgent need for further monitoring and improved management on El Tucuche, but also on Cerro del Aripo where they are found on the island, as well as in Venezuela.

Nocturnal basking in a freshwater turtle from Trinidad

Scorpion mud turtle (Kinosternon scorpioides). Photo by Renoir Auguste. ||| A recent study was published and it assessed nocturnal basking in freshwater turtles from across the world, including surveys from Trinidad and Tobago. An incidental observation of nocturnal basking was recorded with the scorpion mud turtle in an urban area in southern Trinidad which was included in the global assessment. Further, surveys using wildlife cameras took place at Point-a-Pierre Wildfowl Trust to further evaluate whether turtles were basking at night, or only during the day. The only species caught on cameras were the non-native red-eared sliders (Trachemys scripta elegans; native to the United States), and they were only recorded basking during the day. Interestingly, globally, only tropical (but not temperate) species were observed basking at night, suggesting that environmental temperature plays a key role in this behaviour. It would be noteworthy if more observations of basking behaviour are recorded for the other freshwater turtle species in Trinidad. I encourage local herpers and herpetologists to keep an eye on the freshwater turtles near them, so we can use the information to better protect them! ||| Link to early view of study here.

Amphibians and their Conservation in Trinidad and Tobago

A new book has been published "The Conservation and Biogeography of Amphibians in the Caribbean". In it, Chapter 12 features an updated review of the "Amphibians and their conservation in Trinidad and Tobago". The book is edited by Neftali Rios-Lopez and Harold Heatwole, published by Pelagic Publishing. Summary of the book's description: An expansive and detailed review of the biology of Caribbean amphibians, considering their threats, conservation and outlook in a changing world. Amphibians are the group of vertebrates undergoing the fastest rate of extinction; it is urgent that we understand the causes of this and find means of protecting them. This landmark illustrated volume brings together the leading experts in the field. As well as offering an overview of the region as a whole, individual chapters are devoted to each island or island-group and the measures used to protect their amphibians through legislation or nature reserves. The biological background of insular biogeography, including its methods, analysis and results, is reviewed and applied specifically to the problems of Caribbean amphibians – this includes a re-examination of patterns and general ideas about the status of amphibians in the Anthropocene. The Conservation and Biogeography of Amphibians in the Caribbean offers an important baseline against which future amphibian conservation can be measured in the face of climate change, rising sea level and a burgeoning human population. The book can be bought on NHBS or Amazon. DOI: 10.53061/RCJP8789

Another species name change for one of Trinidad's frog

(Banana tree dwelling frog, Boana platanera - formerly/most recently known as Boana xerophylla, from Trinidad. Photo by Renoir Auguste). There has once again been a change in the species name for one of Trinidad and Tobago's frogs. The species (and genus) name for this frog has gone through many changes. From Hyla crepitans - Hypsiboas crepitans - Boana crepitans - Boana xerophylla - now, it is Boana platanera for all populations north of the Orinoco Basin (including Trinidad and Tobago populations) based on updated genetic and call data (link to study here). This is no doubt a challenge to persons and organizations adapting and keeping up with the correct list of species names found here in the country. But these taxonomic changes do serve an important purpose as it sheds light on species diversity. It may not be surprising if the name chamges again, as more data comes through. But for now, the rattled-voice or emerald-eyed tree frog will be updated to be known as the Banana tree dwelling frog, Boana platanera, here, in Trinidad and Tobago.

Cloacal prolapse in a Trinidad frog

Photo of Emerald-eyed treefrog (Boana xerophylla) by Renoir Auguste. In the latest edition of the journal Herpetological Review 53(3) 2022: page 464, features a natural hsitory note documenting cloacal prolapse in a local frog found across Trinidad and Tobago. To learn more about it, see the link here. Click on Herpetological Review 53, under edition 3, natural history notes, download pdf, page 464.

Herping in Trinidad and Tobago (Part 1): Environmentally Sensitive Areas

(Aripo Savannas Environmentally Sensitive Area, Trinidad. Photo by Renoir Auguste). Currently, there are tree designated Environmentally Sensitive Areas (ESAs) in Trinidad and Tobago: The Aripo Savannas, Matura, and Nariva Swamp. Each comprises a variety of hbitats, from savanna grassland, to wet forests, coastal beaches, and marsh swamps. Because of this, there are a high diversity of amphibians and reptiles. Example of some of the herpetofauna found in these ESAs can be found here and here. For local and international persons interested in seeing native herpetofauna, these three areas are highly recommended. Whether you want to see nesting leatherback turtles, venomous snakes, or a range of frog species, Trinidad's three ESAs are the places to visit. All three do require permits to enter from the Forestry Division of Trinidad and Tobago. For persons not familiar, hiring a guide is strongly recommended, and needed (for Matura beach). For more information on herping in Trinidad's three ESAs, do not hesitate to contact me. Stay tuned for a follow up post where I will highlight other areas in Trinidad and Tobago where herping would be must see places to check out!

(The venomous Bothrops atrox, Fer-de-lance, observed in Matura, Trinidad. Photo by Renoir Auguste).

(Rhinoclemmys punctularia, Painted-wood turtle, observed in Aripo Savannas, Trinidad. Photo by Renoir Auguste).

(Pseudis paradoxa, paradox frog, observed in Nariva Swamp, Trinidad. Photo by Renoir Auguste).

One of Trinidad's elusive frogs: is it restricted to the southwest of the island?

(Photograph by Renoir Auguste). Barbour's thin-toed ditch frog (Leptodactylus insularum) is widely found across South America. In Trinidad, though, records of this frog are mostly only from southwest Trinidad - near Icacos and Cedros (Murphy et al. 2018). Or so we thought? Recently, the frog has been observed (by me) in southeast Trinidad - at the same locality over both wet season in August 2021 and the dry season in May 2022. This suggests that a stable population occurs there, in addition to the population in southwest Trinidad. This is a native frog species that feeds on insects. They have also been found to have important antimicrobial properties in their skin, thus offering potential medical importance to people. Greater appreciation and effort are needed to protect this elusive frog from southern Trinidad. To learn more about the frogs found in Trinidad and Tobago, and why they are important to the environment and people, check out the Field Guide to the Amphibians and Reptiles of Trinidad and Tobago (link).

Conservation of three endemic Pristimantis frogs in Trinidad and Tobago

Pristimantis is one of the most species rich genus of animals on Earth. Trinidad and Tobago has three species of frogs in that genus. One is found in Trinidad and Tobago (Urich's litter frog Pristimantis urichi), the other two are found on Tobago only (Charlotteville litter frog P. charlottevillensis, and Turpin's litter frog P. turpinorum). A recent published study (link here) provided updated and novel information on the ecology, conservation status, and genetics of these frogs. Based on the conservation status, the frogs were previously listed as Vulnerable, Least Concern, and Vulnerable, respectively (for P. urichi, P. charlottevillensis, P. turpinorum). However, based on the ecological information such as distribution and relative abundance, these were amended to be Least Concern, Vulnerable, and Data Deficient, respectively. More genetic data are needed for populations in South America, but data in this study found that P. turpinorum is closely related to Venezuelan species, more so than P. urichi and P. charlottevillensis. Further biological information is needed, especially for P. turpinorum which was classified as Data Deficient. How threats such as climate change and land use change will affect these frogs remain larely unknown. Hopefully these gaps will be filled in the near future so as to protect these unique and endemic frogs which play an integral role in biodiversity. To learn more about one of these three frogs, see this local newspaper story feature (link here).

Pristimantis turpinorum pair observed in the Main Ridge Forest Reserve. Photo by Renoir Auguste.

Rediscovery of an elusive snake in Tobago

Snakes are often elusive animals. One can be walking along a forest trail and there could be one hiding in plain sight. The elusiveness of snakes, though, has resulted in some species not being observed for many years, sometimes even for decades. Observing elusive snakes in nature, can thus be rewarding and beneficial, not only for snake enthusiasts, but for the conservation of the species and biodiversity. An example of a snake that was recently rediscovered on the island of Tobago after going many years without being observed is the Hallowell's ground snake (Atractus fuliginosus). This small harmless snake (up to 30cm long) is a forest dwelling snake that lives in leaf litter. They feed on small soil invertebrates, making them important components of ecological food webs. A recent publication (reference below) documents updated records of this elusive snake on the island of Tobago (West Indies) over the past 7 years where records prior were scarce for more than a decade. Natural history notes on the species were documented based on these rare observations, and bioloigsts now know more about the snake. Perhaps this elusive snake is more common than we realise. Or worse, perhaps it is in danger of becoming extinct.

Hallowell's ground snake, Atractus fuliginosus. Photo by Renoir Auguste. || Reference: Murphy, J.C., Braswell, A.L., Weems, J., Auguste, R.J., Rivas, G.A., Rutherford, M.G., Schargel, W.E., and Jowers, M.J. 2021. The Rediscovery of Hallowell’s Ground Snake, Atractus fuliginosus, on Tobago with Notes on its Natural History. Herpetological Review 52(3): 488-492.

The importance of surveying Herpetofauna in EIAs

Painted wood turtle aka Galap (Rhinoclemmys punctularia). Photo by Renoir Auguste. An Environmental Impact Assessment (EIA) is an important tool used to help mitigate threats to biodiversity during anthropogenic development. Ecological surveys of fauna and flora are a core component of EIAs to gauge potential threats to wildlife in a proposed development area. Among fauna surveyed, the majority of assessments historically surved have been done on birds (for terrestrial areas) and freshwater and marine benthic organisms (for aquatic areas). Birds are relatively easy to survey. They often fly within sight, and also have distinct calls for the more secretive species. However, herpetofauna (amphibians and reptiles) should be given more consdieration for all EIAs moving forward. Amphibians are among the most threatened animals globally. They are sensitive to both terrestrial and aquatic pollution, and are especially susceptible to habitat loss. Amphibians would make ideal organisms to assess the biodiversity of a particular area. In addition to their sensitivity to habitat alteration, they make up important components of ecosystems, acting as predator and prey to a variety of other animals, and also can provide health benefits to people through research on their medically important compounds and diet comprising disease carrying mosquitoes. Amphibians can be secretive in habitats where they occur, but like birds, they also have species specific calls that can be used to identify and more easily record their presence. Trained herpetologists who can identify frog calls can thereofore be useed to help survey amphibians in an area. Reptiles also comprise important animals in ecosystems. They are mostly predators but also prey to many other animals. However, unlike amphibians, they do not make species specific calls (except some geckos), so tend to be more challenging to survey quantitatively. Reptiles (e.g. lizards), though, do tend to sometimes exhibit site fidelity, which means they like sticking around a particular area. This could then be used to assess where they like to live, and environmental conditions they prefer. This information can better inform EIAs. There are a lack of trained herpetologists that can identify frog calls and identify certain elusive reptiles in the country. If you are an EIA reviewer, developer, or consultant, we urge you to consider having herpetofauna as species to be surveyed in EIAs. Surveying for one taxa but not other major ones leaves an important gap in how biodviersity could be impacted by development. It is our responsibility to ensure all wildlife are managed sustainably. For more information on this post, do not hesitate to contact the author.

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