Frogs

Icaco Valley Frog Survey, 11th June 2023

Icaco Valley Frog Survey, 11th June 2023

A cooperative agreement between the Caribbean USFWS and the University of Florida (UF) just completed the last coquí guajón (E. cooki) survey for this project at one of the populations within Las Casas de la Selva property.

Last time this population was surveyed was back in 2013, with Norman Greenhawk. Despite the recent heat wave, the team led by Dr. Ana Longo and her graduate students (https://thelongolab.com/), was able to catch and release 30 coquí guajón frogs.

Coquí guajón, Eleutherodactylus cooki, juvenile in Icaco Valley, Patillas, Photo by JP Zegarra

Survey effort included general frog counts, genetic samples, chytrid fungus swabs and tick prevalence. This population is quite unique since it is one of the few known coquí guajón populations to co-occur with both the coquí caoba (E. richmondi) and the coquí melodioso (E. wightmanae), among other species.

Another peculiarity is that this coquí guajón population lacks ticks, perhaps because of its protected habitat and farther distance from human disturbance. In general, this coquí guajón population seems in good condition, but there are concerns with the potential effects of climate change on all coquí frog species. Ultimately, the consequences of these anomalies in demographic responses might not be immediately apparent, and can potentially affect reproduction and recruitment in the coquí guajón populations and other species as well.

Thanks to Jan P. Zegarra (Fish & Wildlife Biologist) for the info and these great photos from this recent survey, care of USFWS-Caribbean Ecological Services Field Office.

Coquí caoba, Eleutherodactylus richmondi, Icaco Valley, Patillas, Photo by JP Zegarra
Taking chytrid fungus swabs

Earthwatch Teen Team Expedition, June 2016

June was a very wet month, and we hosted an intrepid Earthwatch Teen team, that went way beyond comfort zones during their ten day stay. This Earthwatch Teen Team braved sometimes torrential rains to assist Principal Investigator Norman Greenhawk collecting Chytrid samples along the Ethnobotanical Nature Trail. The teens learnt teamwork rapidly and became skilled at how to set up collection plots, becoming familiar with the use of the compass, measuring tape, and twine. After letting the plots rest for two days, the team returned and conducted leaf-litter surveys, searching the fallen leaves and detritus of the forest floor for frogs and Sphaerodactylus geckos. All captured animals were weighed and measured, and all amphibians were swabbed to test for the presence of Batrachochytrium dendrobatidis (Bd), a fungus that can cause the amphibian disease Chytridiomycosis. This collection event is a part of Norman’s ongoing monitoring of Bd at Las Casas de la Selva.
See more about the Chytrid fungus: https://www.amphibiaweb.org/chytrid/chytridiomycosis.html
This team also measured and re-tagged 110 mahoe trees, (Hibiscus elatus), which are part of long-term study plots at Las Casas de la Selva, with Principal Investigator 3t Vakil.

Images by 3t and Chelsea Kyffin, who was the teen team facilitator.

Earthwatch Team: December 2014 -January 2015

Back L-R: Stan Rullman Cindy Stieger, Margaret Baisley, PI Norman Greenhawk
Front L-R: PI 3t Vakil, Charlotte Field, Colleen Casey, Andrés Rúa
All pix on this page thanks to all above.

See Stan’s Blog about this trip!
https://earthwatchunlocked.wordpress.com/2015/04/30/from-trees-to-coquis-an-earthwatch-scientist-explores-puerto-ricos-rainforest/ 2015

Herpetological Survey 2014 led by Norman Greenhawk

HERPETOLOGICAL EXPEDITION JULY-AUGUST 2014

The steep and remote areas of Icaco and Hormiga Valleys of Las Casas de la Selva have never been surveyed for amphibians. Herpetologist Norman Greenhawk led a team of volunteers into the forest to search for target species of frogs in this vast area, to identify and gather information about amphibians to better assist with the future management of this area. The expedition started on 16th July, and continued to 8th August 2014. The team set up camp in the forest, prepared their own food, and faced some days of extremely challenging windy and rainy weather, including an interruption of the study by Tropical Storm Bertha! The team included college students from the continental US, Puerto Rico, an Earthwatch Teen Team, and Dr. Gabriela Agostini from Argentina. They and came back with a lot of data.

The target species that were confirmed to exist in the valleys were: IUCN Endangered Eleutherodactylus wightmanae (the Coqui Melodioso), IUCN Vulnerable Eleutherodactylus cooki (Coqui Guajon), and IUCN Critically endangered Eleutherodactylus richmondi (Coqui Caoba).

During the surveys, the team sampled for Chytridiomycosis, an infectious disease of amphibians, caused by the chytrid Batrachochytrium dendrobatidis, a non-hyphal zoosporic fungus, that is currently killing off amphibians around the world. GPS co-ordinates of appropriate information were taken to allow for mapping of the range of target species within the valley, and high quality photos of the frogs were taken to help show the myriad variation of colors and patterns within a single species.

The initial survey is over and the data is being compiled. Norman has met with personnel of the US Fish and Wildlife Service to help determine future monitoring and research. Once the results of the Chytrid sampling are delivered from the San Diego Zoo, a report will be written up and submitted to a peer-reviewed journal for publication. This survey will continue with a smaller team, as the mountain ridge that separates the two valleys needs to be accessed and sampled.

Norman expresses deep gratitude to team members Sarah Bryan, Jessica Rosado, Marla Gonzalez, Sara Gabel, Sara Zlotnik, Alessandra Belmonte, Sam Boas, Kaitlin Panzer, Lauren Billy, and co-team leader Gabi Agostini. Huge thanks also to Earthwatch Team members: Alana Salas-Yoshii, Josie Icaza, Samantha Riesberg, and their facilitator, Sushmita Sridhar.

Big, big thanks to the Mohammad bin Zayed Species Conservation Fund, CREOi, Roland Pesch and Kathy Rosskoph, without whom this survey would not have been able to be carried through.

Lastly, a special thanks to Thrity Vakil & Andrés Rúa for help with logistics, Leah Chevrier-Rappaport for extra volunteer help, and to Jan Zegarra of the US Fish & Wildlife Service for his encouragement, help with analyzing the results, and for consultation concerning future research possibilities.

Meet the team:
L-R Back: Sam Boas, Norman Greenhawk, Marla M. Barrios González, Lauren Billy, Alessandra Belmonte, Sara Gabel.
L-R Front: Leah Chevrier-Rappaport, Sarah Bryan, Jessica Rosado, Gabriela Agostini, Sara Zlotnik

EARTHWATCH PARTICIPATION:
For several days of the survey, the team also comprised of three teenage Earthwatchers, Alana Salas-Yoshii, Josie Icaza, Samantha Riesberg, and their facilitator, Sushmita Sridhar.

Photo credits: Norman Greenhawk, 3t Vakil, Andrés Rúa, and Dr. Gabi Agostini (frog pix below).

Herpetology in Puerto Rico

Norman has been invited to give a presentation of his work at The University of Puerto Rico in February 2014.

Norman Greenhawk was away from Las Casas de la Selva for the majority of 2013, from April through Mid-November, on travel and training on the Earthwatch Neville Shulman Award for Emerging Environmental Leaders. Norman won the award based on his proposal to study not only various species of reptiles and amphibians, but also to conduct ethno-herpetological interviews with local people through Central and South America to record attitudes, uses (medicinal, ritual, economic, etc), and beliefs about frogs, snakes, lizards, and crocodiles.

Norman’s travels took him to Panama, where he studied with the brilliant Dr. Julie Ray of La MICA and with the Smithsonian’s Panama Amphibian Rescue and Conservation project. Norman learned to catch and relocate endangered crocodiles with the American Crocodile Education Sanctuary in Belize. In Honduras, Norman learned the finer points of monitoring the endemic Utila Island Iguana, a species of lizard that is adapted to inhabit only the mangrove swamps of Utila Island. Norman ended his trip with a month in Bolivia, studying critically endangered frogs and interviewing the indigenous people who ran the “Mercado de las Brujas”.

Upon his return to Las Casas, Norman led an expedition into Icaco Valley with Jan Zegarra of the US FWS, and Maria Cristina of Universidad Metropolitana. The purpose of the trip was to monitor the population of Eleutherodactylus cooki, the “Coqui Guajon” that Norman discovered in December 2012, but there was a pleasant surprise. This expedition confirmed the presence of Eleutherodactylus richmondi, the “Coqui Caoba”, an IUCN critically-endangerd frog. According to Jan, whose Master’s thesis was on E. richmondi, there is only one other area in all of Puerto Rico where E. cooki and E. richmondi share habitat; Jan said this makes Icaco is a very special and unique location.

Frogging

Frogging at Las Casas de la Selva! Patricia Caligari (center) is pursuing a Masters Degree at University of Puerto Rico. L-R: Rosangela, Michel, Naomi and Monica are her assistants in the field and they are taking credits as part of their bachelor degrees.

Geographic assessment of the response of three different endemic Puerto Rican anurans to the pathogenic fungus Batrachochytrium dendrobatidis (Bd)

ABSTRACT

Chytridiomycosis is a lethal infectious disease caused by the pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd), which is responsible for the extinction of many amphibians worldwide. In Puerto Rico three species of Eleutherodactylus disappeared potentially due to this pathogen, and many others are at risk. A synergistic effect between Bd and climate was shown for two species at El Yunque, but this relationship has not been tested in other species or forests. The purpose of this study is to evaluate the status of Bd in three endemic species, Eleutherodactylus wightmanae, Eleutherodactylus coqui, and Leptodactylus albilabris, which differ in conservation status, ecology and life history, in three highland forests across the island. Results from this study will enhance our understanding of the mechanisms of Bd under enzootic conditions.

Her advisor is Dr. Patricia Burrowes, who also co-authored our biodiversity and frog study paper.

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