THE HERPETOFAUNA OF ESTACIÓN BIOLÓGICA LAS GUACAMAYAS AND SURROUNDING AREAS, SOUTH EAST LAGUNA DEL TIGRE NATIONAL PARK.

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1 LAGUNA DEL TIGRE 2016 GUATEMALA THE HERPETOFAUNA OF ESTACIÓN BIOLÓGICA LAS GUACAMAYAS AND SURROUNDING AREAS, SOUTH EAST LAGUNA DEL TIGRE NATIONAL PARK. Authors: Rowland Griffin and Adela Mei. Translation: Sheriyar Bokhari.

2 2016 THE HERPETOFAUNA OF ESTACIÓN BIOLÓGICA LAS GUACAMAYAS AND SURROUNDING AREAS, SOUTH EAST LAGUNA DEL TIGRE NATIONAL PARK 2016 CONAP Licencia de Investigacion: DRP01/2016 Authors: Rowland Griffin and Adela Mei Translation: Sheriyar Bokhari 15 March 2017 Indigo Expeditions 0 2

3 Introduction Introduction Although the herpetofauna of the Yucatán Peninsular, including some areas of El Petén, is relatively well documented, we know little about the herpetofaunal assemblage at Estación Biológica las Guacamayas (EBG) or the Laguna del Tigre National Park (PNLT). Surveys have so far been limited to monitoring the populations of the endemic Morelet s crocodile (Crocodylus moreletii) and Central American river turtle (Dermatemys mawii) and conducting transects along a 500m stretch of the river bank (Bestelmeyer & Alonso 2000). Objectives 1. Establish a complete inventory of the herpetofauna of EBG and the surrounding area. 2. Study the effects of agriculture on the diversity of amphibians and reptiles. 3. Technical and professional volunteers will be involved in these studies. They will attend a series of training sessions, which will cover the following topics: 1. Study techniques, 2. Identification of species, and 3. Management of venomous snakes, and recording of data. 0 3

4 Background Background EBG has a varied landscape within and bordering its reserve land. EBG is situated at the southern border of the Laguna del Tigre National Park (LTNP), the border of which is delineated by the Rio San Pedro. The LTNP side of the river is characterised by the presence of limestone outcrops that rise relatively sharply from the river bed, the vegetation here is Tropical Dry Forest. The southern side of the river is a flat landscape of seasonally inundated grass/swamps and thorn scrub that borders the Rio San Pedro and Rio Sacluc. To the East the Tropical Dry Forest in bordered by agriculture of the local community, known as Paso Caballos. The Tropical Dry Forest of LTNP on the northern bank of the Rio San Pedro is heterogenous because as the limestone bedrock undulates the composition of the flora changes. In particular, on the peaks there is very little leaf litter as it gets washed into the troughs by rainfall. Due to this it is possible that the herpetofaunal assemblages within the peaks and troughs are very different. By surveying various areas throughout all of these habitats Indigo Expeditions aims to better understand not only the composition of the herpetofaunal communities at EBG, but also what effects the presence of agriculture has on the herpetofaunal community structure at the eastern border of the forest. 0 4

5 Hypothesis Justifications Reptiles and amphibians are widely known to be suffering significant global population declines. They are also been less studied than other taxa, and relatively little known of their ecological requirements. The collection of data on the reptile and amphibian communities EBG will allow a better understanding of the ecology of amphibians and reptiles in LTNP, and of the effects of human activity on these species. Hypothesis 1. Herpetofaunal communities will vary significantly along man-made edges compared to natural edges. 2. Herpetofaunal communities vary significantly in edge habitat compared to forest habitat. 3. Herpetofaunal communities vary significantly in high forests compared to low forests. 0 5

6 Methodology Description of the study area The location of the project is the Las Guacamayas Biological Station and adjacent areas in the south-east area of the Laguna del Tigre National Park, San Andrés, Petén. It has a land area of 5050 hectares, the forest ecosystem corresponds to primary forest and is complemented by wetlands and floodplains near the San Pedro River and Sacluc River bordering the Paso Caballos community. This community is made up of a total of 120 families of the Q'eqchí ethnic group, whose productive habits are based on traditional monoculture agriculture, basically cultivating maize, squash, and beans. This research project will concentrate its efforts on the forests around the Las Guacamayas Biological Station and the San Pedro and Sacluc rivers and their associated terrestrial habitats. 0 6

7 Methodology Methods Visual Encounter Surveys (VES) Transects were walked at a suitably slow enough pace to allow thorough examination of the vegetation for reptiles and amphibians. The vegetation surrounding each transect was surveyed up to one metre either side of the transect and up to two metres in height. Each transect was surveyed at least once during the day and twice during the night. At the start of each transect the following environmental data was recorded: time of start(24hr), air temperature (ºC), relative humidity (%), and cloud cover (%). Additionally, time of finish of each transect (24hr), daily rainfall (mm), daily barometric pressure (hpa) and daily moon phase were recorded. When safe to do so, each individual encountered was captured and the following data recorded: time encountered (24hr), location using a Garmin GPSmap 62s, activity (rest, basking, foraging), position (leaf litter, shrub layer, branch [if on a branch the diameter of the perch was measured in cm], and height from ground [cm]) each individual was first observed body temperature before capture (if possible and calculated with an infrared thermometer in ºC), species, age (adult, juvenile, neonate), sex (if possible), length (mm) and weight (g). Biometric data for amphibians and most lizards was taken in the field. All snakes captured were brought back to EBG for collection of biometric data for ease and were marked for identification using cautery branding of the ventral scales following an adapted method described by Winne et al. (2006), see Appendix 1 for details of the marking scheme. All individuals were released at the point of capture within 48 hours. 0 7

8 Results Results During 2016 Indigo Expedition field teams recorded 62 species of amphibian and reptiles, including three species of reptiles for the first time, in LTNP. The new records were the Anguid lizard, Celestus rozellae a forest canopy specialist, and two Colubrid snakes, Coluber mentovarius and Pseudelaphe flavirufa. Since 2013 Indigo Expeditions has recorded at total of 89 species of amphibian and reptile in LTNP, including 20 species of amphibian, 26 species of lizard, 37 species of snake, five species of turtle, and one species of crocodylian (Appendix II). Including the two species (one species of frog, Dendropsophus ebracatta, and one species of turtle, Staurotypus triporcatus) recorded by Moya et al (2000) but not yet recorded by Indigo Expeditions, LTNP is home to 91 species of amphibian and reptile. During 2016 no snakes were marked or ventral scales clipped for DNA samples. No quadrats were performed during June to August 2016 A total of 24 transect surveys were conducted between 30th June and 22nd August Eight individuals of seven species (two amphibians and five reptiles) were recorded from seven transect surveys (29.2% of transects). The remaining 17 transect surveys (70.8%) yielded no observations of amphibians or reptiles. Observations were made in three of the four habitat categories (AE, BA, and BB). Observations were highest in AE and BB, both accounting for 37.5% of observations (Table 1). The highest number species was observed in BB. No observations were made in NE. Only the reptile Norops capito was observed more than once (two individuals). 0 8

9 Results November 2016 A total of 27 transect surveys were conducted between 14th and 22nd November Nine individuals of four species (two amphibians and two reptiles) were recorded from eight transect surveys (29.6% of transects). The remaining 19 transect surveys (70.4%) yielded no observations of amphibians or reptiles. Observations were made in all three habitat categories (Table 2). Both observations of amphibians and reptiles, and number of species were highest in Forest Edge (44.4% and three species respectively). The most commonly observed species was the amphibian Hypopachus variolosus, which accounted for 44.4% of observations (four individuals) and was observed in all habitat categories. The amphibian Smilisca baudini was found in two habitat categories and accounted for 33.3% of observations (three individuals). The two reptile species, Norops uniformis and Spilotes pullatus, were only observed once each. Spilotes pullatus was identified from a shed skin. 0 9

10 Discussion Discussion Since 2013, the work of Indigo Expeditions has increased the amphibian and reptile species list from 36 to 91 (Moya et al 2000). That, after four years of survey work, species are still being added to this list (three species in 2016) is testament to the diversity of amphibian and reptile fauna of Laguna del Tigre National Park and serves to highlight the importance of the area for conservation in the Maya Biosphere Reserve. Although overall the number of species observed is consistent with other years, observations of individuals during survey (not including casual observations) was much lower than in previous years. This is a likely effect of low rainfall during the El Niño cycle of We expect that after the increased rainfall patterns of 2016 that observations of amphibians and reptiles will increase again in The observation of the highly seasonal amphibian Rhinophrynus dorsalis at the ponds in EBG is worthy of note. This is the first record of the species at the station, and marks only the second observation of the species in the national park. Five individuals were observed calling for approximately three hours before they returned underground. They were not heard calling again. It will be interesting to see if they call again in Recommendations It is the recommendation of this report that monitoring of the amphibian and reptile fauna of Laguna del Tigre National Park be continued in Additionally studies into the effects of agriculture on amphibian and reptile diversity should be continued and expanded upon in Acknowledgements Indigo Expeditions would like to thank the staff of the regional office of the Consejo Nacional de Areas Protegidas for their continued support to our research. We also thank Jeovany Tut Rodriguez, Cornelio Chable and the staff at Estación Biológica Las Guacamayas for their support and enthusiasm. Finally we thank Indigo Expeditions volunteers for their commitment in the field and without whom this research would not have been possible. 0 10

11 References References Heyer, W.R., Donnelly, M.A., McDiarmid, R.W., Hayek, L-A.C. and Foster, M.S Measuring and Monitoring Biological Diversity: Standard Methods for Amphibians. Smithsonian Institution Press. Washington. Lee, J.C The Amphibians and Reptiles of the Yucatán Peninsular. Comstock, Michican. McDiarmid, R.W., Foster, M.S., Guyer, C., Gibbons, J.W. and Chernoff., N Reptile Biodiversity: Standard Methods for Inventory and Monitoring. University of California Press. Berkeley. Moya, F.C., Lara, O. and Queral-Regil, A The Herpetofauna of Laguna del Tigre National Park, Petén, Guatemala, with an Emphasis on Populations of the Morelet s Crocodile (Crocodylus moreletii). Pp in A Biological Assessment of Laguna del Tigre National Park, Petén, Guatemala. RAP Bulletin of Biological Assessment 16 (Bestelmeyer, B.T. and Alonso, L.E. eds). Conservation International, Washington. Winne, C.T., Willson, J.D., Andrews, K.M. and Reed., R.N Efficacy of Marking Snakes with Disposable Medical Cautery Units. Herpetological Review. 37:1. Pp

12 Appendix 1 Diagram for marking snakes using electrocautery ophthalmic medical pens. In this example the individual has been marked with the ID number 36 ( from Winne et al. 2006). 0 12

13 Appendix 2 List of species recorded at EBG by Indigo Expeditions in Species of Amphibians and Reptiles found in Laguna del Tigre National Park in 2016 AMPHIBIA CAUDATA Cas obs Jun - Aug 16 Survey Jun - Aug 1 Bolitoglossa mexicana X X ANURA 2 Rhinella marina X 16 Cas obs Nov 16 3 Incilius valliceps X X Survey Nov 16 Previously known but not recorded in 4 Gastrophryne elegans X 5 Hypopachus variolosus X X X 6 Agalychnis callidryas X 7 Dendropsophus X microcephala 8 Scinax staufferi X 9 Smilisca baudinii X X X X 10 Tlalocohyla loquax X 11 Tlalocohyla picta X 12 Trachycephalus venulosus X 13 Triprion petasatus X 14 Engystomops pustulosus X X 15 Eleutherodactylus leprus X 16 Leptodactylus fragilis X X 17 Leptodactylus X X melanolotus 18 Rana brownorum X X 19 Rana vaillanti X 20 Rhinophrynus dorsalis X REPTILIA SQUAMATA / SAURIA 21 Coleonyx elegans X X 22 Hemidactylus frenatus X 23 Sphaerodactylus glaucus X X 24 Sphaerodactylus millepunctatus 25 Thecadactylus rapicauda X 26 Celestus rozellae X 27 Holcosus festiva X X

14 Appendix 2 Species of Amphibians and Reptiles found in Laguna del Tigre National Park in 2016 Cas obs Jun - Aug Holcosus undulatus X X X 29 Basiliscus vittatus X X 30 Corytophanes cristatus X 31 Corytophanes hernandezii X 32 Iguana iguana X 33 Norops beckeri X Survey Jun - Aug Cas obs Nov Norops capito X X 35 Norops lemurinus X X Survey Nov 16 Previously known but not recorded in 36 Norops rodriguezii X 37 Norops sagrei X 38 Norops sericeus X 39 Norops tropidonotus X 40 Norops uniformis X X 41 Sceloporus chrysostictus X 42 Sceloporus teapensis X X 43 Eumeces sumichrasti X 44 Mabuya unimarginata X 45 Mesoscincus schwartzei X X 46 Sphenomorphus cherriei X SQUAMATA / SERPENTES 47 Boa constrictor X X 48 Adelphicos quadrivirgatus X 49 Clelia scytalina X 50 Coluber mentovarius X 51 Coniophanes bipunctatus X 52 Coniophanes imperialis X X 53 Coniophanes schmidtii X X 54 Drymarchon melanurus X 55 Drymobius margaritiferus X X 56 Ficimia publia X 57 Lampropeltis abnorma X 58 Leptodeira frenata X 59 Leptodeira septentrionalis X 60 Leptophis ahaetulla X 61 Leptophis mexicana X

15 Appendix 2 Species of Amphibians and Reptiles found in Laguna del Tigre National Park in 2016 Cas obs Jun - Aug Survey Jun - Aug Cas obs Nov Imantodes cenchoa X X Survey Nov 16 Previously known but not recorded in 63 Mastigodryas X melanolomus 64 Ninia diademata X 65 Ninia sebae X 66 Oxybelis aeneus X 67 Oxybelis fulgidus X 68 Oxyrhopus petolarius X X 69 Pliocercus elapoides X 70 Pseudelaphe flavirufa X 71 Scaphiodontophis X annulatus 72 Sibon dimidiata X 73 Sibon nebulatus X 74 Spilotes pullatus X 75 Tantilla moesta X 76 Tantillita canula X 77 Thamnophis proximus X 78 Tretanorhinus nigroluteus X 79 Tropidodipsas fasciatus X 80 Tropidodipsas sartorii X 81 Xenodon rabdocephalus X 82 Micrurus diastema X 83 Bothrops asper X X TESTUDINATA 84 Dermatemys mawii X X 85 Kinosternon acutum X X 86 Kinosternon leucostomum X 87 Rhinoclemmys areolata X X 88 Trachemys scripta X CROCODILIA 89 Crocodylus moreletii X X

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LAGUNA DEL TIGRE The Herpetofauna of Estación Biológica las Guacamayas and Surrounding Areas. Laguna del Tigre National Park, Guatemala

LAGUNA DEL TIGRE The Herpetofauna of Estación Biológica las Guacamayas and Surrounding Areas. Laguna del Tigre National Park, Guatemala LAGUNA DEL TIGRE 2013-2014 The Herpetofauna of Estación Biológica las Guacamayas and Surrounding Areas Laguna del Tigre National Park, Guatemala Author: Rowland Griffin. Translation: Aitor Cevidanes. License: