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Spring 2018 Herpetofauna of Sumak Allpa: A Baseline Assessment of an Unstudied Island Herpetofaunal Community Sara Freimuth SIT Study Abroad

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Recommended Citation Freimuth, Sara, "Herpetofauna of Sumak Allpa: A Baseline Assessment of an Unstudied Island Herpetofaunal Community" (2018). Independent Study Project (ISP) Collection. 2784. https://digitalcollections.sit.edu/isp_collection/2784

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Herpetofauna of Sumak Allpa: A Baseline Assessment of an Unstudied Island Herpetofaunal Community

Freimuth, Sara Academic Director: Silva, Xavier, PhD Project Advisor: Wagner, Martina, MSc Claremont McKenna College Organismal Biology and Spanish South America, Ecuador, Orellana, Sumak Allpa Submitted in partial fulfillment of the requirements for Ecuador Comparative Ecology and Conservation, SIT Study Abroad, Spring 2018

Abstract Sumak Allpa is an island dedicated to the provision and protection of habitat for the conservation and rehabilitation of primates. As such, the island - a varzea ecosystem located in the Western Amazon of Ecuador, one of the most biodiverse and also most threatened regions in the world – consists of protected primary forest that is home not only to a variety of primates, but also to an even wider variety of other taxa, nearly all of which have gone unstudied on the island. The present investigation assessed two of those taxa, amphibians and reptiles, in order to establish a baseline inventory of the island’s herpetofaunal community and provide a preliminary assessment of its composition, activity, and habitat use as a way to suggest and inform future investigations for the study and monitoring of the community and its populations. Through 78 hours of visual and acoustic encounter surveys spanned across 16 days, a community of 552 individuals representing 15 species of 5 families of Anura and 11 species of 7 families of Squamata was observed on the island. Analysis of this community indicated high species richness and low species diversity and that the majority of species are capable of occupying all of the island’s habitats, demonstrating preferences for specific habitat characteristics such as leaf litter microhabitats and high density understory vegetation. An additional analysis of the population of Adenomera hylaedactyla, a species accounting for 57.4% of all individuals encountered, also demonstrated these same overall community trends, and this particular population had an average snout-vent-length (SVL) much smaller than the average SVL reported for the species overall. Collectively, these findings indicate long-term seasonal monitoring of the island and future investigation of its individual populations would best inform the conservation of the island’s herpetofaunal community and fulfill some of the many gaps in the existent knowledge of Ecuadorian and Neotropical herpetofauna more generally.

Resumen Sumak Allpa es una isla dedicada a la provisión y protección del hábitat para la conservación y rehabilitación de primates. Como tal, la isla - un ecosistema de várzea ubicado en la Amazonía occidental de Ecuador, una de las regiones más biodiversas y más amenazadas del mundo - consiste en un bosque primario protegido que alberga no solo una variedad de primates, sino también una variedad aún más amplia de otros taxones, casi todos los cuales no han sido estudiados en la isla. La presente investigación evaluó dos taxones, anfibios y reptiles, con el fin de establecer un inventario de línea de base de la comunidad de herpetofauna de la isla y de proporcionar una evaluación preliminar de su composición, actividad y uso del hábitat como una forma de sugerir e informar investigaciones futuras para el estudio y monitoreo de la comunidad y sus poblaciones. A través de 78 horas de encuestas visuales y acústicas durante 16 días, se observó en la isla una comunidad de 552 individuos que representaban a 15 especies de 5 familias de Anura y 11 especies de 7 familias de Squamata. El análisis de esta comunidad indicó una alta riqueza de especies y baja diversidad de especies y que la mayoría de las especies son capaces de ocupar todos los hábitats de la isla, demostrando preferencias por características específicas del hábitat tales como microhábitats de hojarasca y vegetación de sotobosque de alta densidad. Un análisis adicional de la población de Adenomera hylaedactyla, una especie que representa el 57.4% de todas los individuos encontrados, también demostró estas mismas tendencias generales de la comunidad, y esta población particular tuvo una longitud de rostro- cloacal promedio (LRC) mucho más pequeña que la LRC promedio declarada para la especie en general. Colectivamente, estos hallazgos indican un monitoreo estacional a largo plazo de la isla y la investigación futura de sus poblaciones individuales serían las mejores formas de informar la conservación de la comunidad herpetofauna de la isla y cubrirían algunas de las brechas en el conocimiento existente de la herpetofauna ecuatoriana y neotropical en general.

Acknowledgements A large debt of gratitude is owed to the many people who made this project possible. First, a special thank you belongs to Diana Serrano, Xavier Silva, and Javier Robayo for their continued support throughout the ISP process. This project would not have come to fruition without their constant advice and emotional support. Another special thanks goes to Martina Wagner for welcoming me to the Amazon, sharing with me a plethora of guides and materials for the identification of the region’s herpetofauna, introducing me to all of the trails of the island, and showing me incredible kindness and patience. Further thanks go to Valerio Gualinga for clearing trails and transects for safer nocturnal surveying and to Hector Vargas for his hospitality, compassion, and provision of transportation and delicious warm meals. Lastly, many thanks go to Rachel Meyer and Emily Babb for keeping me sane during my first few days on Sumak Allpa and to Sophie Cash and Krista Smith-Hanke for their friendship, constant reassurance, and extraordinary moral support while sharing this experience with me.

Agradecimientos Se debe una gran deuda de gratitud a las muchas personas que hicieron posible este proyecto. Primero, un agradecimiento especial les pertenece a Diana Serrano, Xavier Silva y Javier Robayo por su continuo apoyo durante todo el proceso de ISP. Este proyecto no habría llegado a buen término sin su constante asesoramiento y apoyo emocional. Otro agradecimiento especial para Martina Wagner por darme la bienvenida a la Amazonía, compartiendo conmigo una plétora de guías y materiales para la identificación de la herpetofauna de la región, presentándome a todos los senderos de la isla y mostrándome una amabilidad y paciencia increíble. Agradezco a Valerio Gualinga por despejar senderos y transectos para realizar estudios nocturnos más seguros y a Héctor Vargas por su hospitalidad, compasión y provisión de transporte y deliciosas comidas calientes. Por último, muchas gracias a Rachel Meyer y Emily Babb por mantenerme cuerda durante mis primeros días en Sumak Allpa y a Sophie Cash y Krista Smith-Hanke por su amistad, consuelo constante y extraordinario apoyo moral mientras compartían esta experiencia conmigo. Introduction Global Herpetofauna: Ecological Functions and Population Declines Although amphibians and reptiles are often considered together in the study of herpetology, these two vertebrate groups that constitute herpetofauna are actually quite different. Derived from lineages that have been independent since 300 million years ago, amphibians and reptiles have quite different life histories with distinct morphological characteristics, reproductive systems, behavioral traits, and ecological requirements (Zug et al., 2001; Costa et al., 2016). Consequently, amphibians and reptiles contribute to a diverse range of ecological functions and herpetofauna constitute abundant and diverse components of many terrestrial and freshwater ecosystems (Young et al., 2004; Tyler et al., 2007; Pough et al., 2004; Wells, 2007; Collins & Crump, 2009), particularly in the Neotropics, where they are among the most abundant and diverse vertebrate taxa (Cortés-Gomez et al., 2016; Stuart et al., 2004). Despite their plenitude in such a wide range of terrestrial and freshwater ecosystems, there has been a generally low level of understanding regarding the ecological functions and services amphibians and reptiles provide (Bickford et al, 2010; Hocking & Babbitt, 2014). Recent studies, however, cite how in spite of their biological and ecological differences, amphibians and reptiles often play very similar ecological roles, contributing to nutrient cycling, bioturbation, seed dispersal, pollination, and energy flow through trophic chains as both predator and prey species (Cortés-Gomez et al., 2016). Other studies also emphasize their provision of ecosystem services to humans, specifically, evidencing their regulation of pest outbreaks and alteration of disease transmission through predation and competition with mosquitoes and disease-carrying fly species, in addition to their use as food, in cultural practices across the globe, and in both Western and traditional medicines (Hocking & Babbitt, 2014). This recent surge in efforts to understand the ecological roles herpetofauna play within ecosystems, nevertheless, has been prompted by a sense of urgency and out of necessity. Amphibian and reptile populations in recent decades have experienced rapid declines and reduction is still ongoing (Gibbons et al., 2000; Lips et al., 2006; Reading et al., 2010; Heatwole 2013). In addition to prompting efforts to better understand the ecological functions of amphibians and reptiles, these declines also have impelled the investigation of specific threats to herpetofauna and the establishment of criteria for the evaluation of the degree of threat to species of amphibians and reptiles (Gibbons et al., 2000; Todd et al., 2010; Stuart et al., 2004; Böhm et al., 2012). Among the most significant threats to amphibian and reptilian populations at the global scale are habitat loss and degradation, introduced invasive species, pollution, disease, unsustainable use, and climate change (Lips et al., 2006; Gibbons et al., 2000; Todd et al., 2010). In the Neotropics, these threats are particularly imminent. Not only does this region contain 49.2% of the world’s amphibian species and significant reptile diversity and richness, but also it has suffered among highest rates of population decline (63.1% for amphibians and about 20% for reptiles) (Stuart et al., 2004; Böhm et al., 2012).

Herpetofauna of Ecuador As one of the 17 megadiverse countries in the world that collectively contain 70% of the animal and plant species on the planet, Ecuador is well represented by a variety of taxa, particularly amphibians and reptiles (Centro Jambatu, 2011). Home to 615 species of amphibians, 236 of which are endemic, Ecuador ranks fourth in the world in amphibian species richness behind Brazil, Colombia, and Peru, respectively (AmphibiaWeb). Given its small relative size, however, Ecuador ranks first in the world for amphibian species richness per unit area, and with 464 recorded species of reptiles, it ranks the same in terms of reptilian species richness per unit area, too (AmphibiaWeb; Reyes-Puig, Almendáriz, & Torres-Carvajal, 2017). Thus, with such species richness condensed in such a small region and high levels of endemism, Ecuador is an important area to consider for the investigation herpetofauna in general, but is especially significant considering the recent trends of Neotropical amphibian and reptile population declines. Despite this significance, few studies have been conducted to assess amphibian and reptilian populations in Ecuador, and very little is known about many of the species that constitute its richness and diversity. The first quantitative study on amphibian decline in Ecuador was not published until 2003, and the first comprehensive quantitative study of reptile conservation in Ecuador was not published until 2017 (Bustamante et al., 2005; Reyes-Puig, Almendáriz, & Torres-Carvajal, 2017). The lack of understanding of the status of Ecuador’s amphibian and reptilian diversity is even further evidenced by how much of it has only been recently discovered. Nearly 10% of all reptilian species in Ecuador have been reported or described in this century alone (Reyes-Puig, Almendáriz, & Torres-Carvajal, 2017), and a large number of amphibian species have been described in the past 5 years alone (e.g. Batallas & Brito, 2014; Reyes-Puig & Yánez-Muñoz, 2012; Brito, Ojala-Barbour, Batallas & Almendáriz, 2016). Assessing these species, especially their baseline population levels and distributions, is crucial to monitoring these new populations for their conservation. Newly described species, however, are not the only understudied populations of herpetofauna in Ecuador. While amphibian species recently have been assessed more extensively (Rodrigues et al., 2006), only about 25% of the species of reptiles from continental Ecuador are listed on the IUCN Red List of Threatened Species and 17% of those listed are Data Deficient (Reyes-Puig, Almendáriz, & Torres-Carvajal, 2017). Ultimately, one of the biggest deficits in the conservation of herpetofauna in Ecuador, and the Neotropics accordingly, is simply the lack baseline knowledge and continued monitoring of its many different species’ populations.

The Ecuadorian Amazon The Amazon is one of the most biodiverse biomes on the planet, and where Ecuador falls in western Amazon, in particular, is especially rich in biodiversity and contains some of the highest levels of amphibian and reptilian species richness in Ecuador (AmphibiaWeb; Reyes- Puig, Almendáriz, & Torres-Carvajal, 2017). The Ecuadorian Amazon is not only species rich, however – the region also happens to be rich in untapped oil reserves, many of which are located in Yasuní National Park, a major protected area within the western Amazon of Ecuador (Bass et al., 2010). Consequently, the ecosystems of Yasuní and the surrounding areas confront numerous threats characteristic of the entire Ecuadorian Amazonian region. Most prominent among these threats is petroleum exploration and exploitation; however, accompanying these projects are transportation projects that open up the region to numerous other threats, including mining, illegal logging, oil palm plantations, and rapid resource exploitation and human development (Bass et al., 2010). Thus, the region’s populations of herpetofauna are at risk for or already are experiencing consequences of these anthropogenic activities, such as habitat loss and degradation and pollution, in addition more general threats such as disease and climate change.

Sumak Allpa and the Present Investigation Sumak Allpa is an island situated in the Ecuadorian Amazon downstream the River Napo from Coca in the vicinity of Yasuní National Park and the namesake of the non-profit primate rehabilitation center that was founded in 2006 by Hector Vargas and is housed on the island (Figure 1). The project concentrates on providing education for the global and local community on the importance of the protection and conservation of the Amazon and also is centered on the protection of native primates from anthropogenic destruction through the use of the island as a sanctuary for primates rescued principally from animal-trafficking in the surrounding area (Zewdie, 2017). As a result of the island’s use for primate rehabilitation, Sumak Allpa contains protected primary forest subject to little human activity beyond infrequent, small-scale tourism that is home not only to primates but also to a wide variety of other taxa that contribute to the health and maintenance of the ecosystem. Few of these other taxa have been investigated formally, if at all, and the island’s herpetofauna had never been assessed before the present investigation.

Sumak Allpa

Figure 1. Satellite imagery of demonstrating where Sumak Allpa is located in Ecuador and how it is situated downstream from Coca, Puerto Francisco de Orellana, Orellana, Ecuador along the Napo River.

The conservation scheme of Sumak Allpa provided by its status as a primate rehabilitation center presents a unique situation for the assessment and continued monitoring of herpetofauna. While the herpetofaunal community is nearly entirely protected from direct anthropogenic threats, such as habitat loss and degradation, due the protection of the ecosystem for primate rehabilitation, the isolation provided by the ecosystem occurring on an island, and the absence of frequent human use, the herpetofauna on the island still may be threatened by generalized threats to the surrounding region. For example, while reduced compared to other sites along the river, Sumak Allpa is still subject to the effects of pollution in both the water and air as a result of petroleum exploitation in the mainland regions around the island. The island also is not exempt from climate change and risk of exposure to invasive species and disease. Thus, Sumak Allpa provides the unique opportunity to study the impacts of such threats using a small and isolated community of herptofauna. Being situated in the heart of the northern Ecuadorian Amazon and within the vicinity of the biodiversity hotspot, Yasuní National Park, the island also contains a small portion of the amphibian and reptile diversity of this important Neotropical region. Though the populations of this diversity are small and made up of common and relatively non-threatened species, Sumak Allpa still carries significance for the conservation of the region’s herpetofauna - some of the Ecuadorian amphibian and reptile species that have poorly understood ecologies and unassessed populations by the IUCN are known to exist on the island. Therefore, as small, contained area, Sumak Allpa serves as an ideal site to study the ecological niches and functions of these species and fill knowledge gaps to better strategize the conservation of these species throughout their entire ranges. Given the unique suitability of Sumak Allpa as a locality for the study of herpetofauna and lack of prior assessment, the present investigation serves two primary purposes: 1) to establish a baseline inventory of the island’s herpetofauna for future studies and 2) to provide a preliminary assessment of the composition, activity, and habitat use of the herpetofaunal community that can be used to inform future studies and monitoring of the community and populations of its species.

Materials & Methods Study Site Sumak Allpa is an island situated in the Napo River 19 kilometers east of Coca, Puerto Francisco de Orellana, Orellana, Ecuador at about 315 m above sea level (0°26'24" S 76°49'02" W). The climate of the island and surrounding area is characterized by high temperatures averaging between 24°C and 27°C, a high annual rainfall of 3,200 mm, high humidity averaging between 80 and 94%, and a mild dry season (Bass et al., 2010). The island contains a varzea ecosystem and experiences various levels of flooding: areas in the northeast are most regularly flooded and more central areas flood only intermittently, while the southwest areas of the island remain dry year-round. The island experienced one inundation event during the time of this study. The forest is recovered from cacao and coffee plantations and now is between 70% and 80% primary forest and 20% and 30% secondary forest (Zewdie, 2017). A small portion of the southwestern shore of the island has been developed for four cabins and a small dock, and aside from the seven maintained trails for research and tourism, the rest of the island is permitted to grow freely and continues to recover (Figure 2).

Figure 2. Satellite image of Sumak Allpa with the seven maintained trails and three convening transects highlighted and labeled. Selection of Surveying Techniques Searches were conducted using a combination of visual encounter surveying and acoustic encounter surveying, two standard techniques for the inventory and monitoring of herpetofauna (Heyer, 1994; Eekhout, 2011; Lambert, 1984). Visual encounter surveying (VES) was selected over other active search techniques, such as quadrat and patch sampling, and passive search techniques, such as pitfall trapping and PVC pipe refugia sampling, as the principle surveying method for this study with the consideration of both the present assessment and future studies. VES has the lowest relative cost and time investment for the inventory and monitoring of the broadest spectrum of herpetofauna and can still be employed successfully when personnel is limited (Heyer, 1994). When utilized in short-term studies, such as this, the VES also has demonstrated significantly higher encounter rates of diurnal amphibians and nocturnal reptiles than other active search techniques and was comparable to such techniques for the detection of nocturnal amphibians and diurnal reptiles in the short-term (Doan 2003). VES is even more effective in combination with other inventory and/or monitoring techniques, to the point where it may even be able to obtain a complete species inventory when paired with an appropriate secondary technique (Eekhout, 2011). Thus, to account for canopy-dwelling and more cryptic calling species, VES was paired with acoustic encounter surveying (AES), another low-cost, low-personnel, and low-time- investment monitoring technique (Heyer, 1994). When used together, these methods have been demonstrated to detect the highest species numbers across families, guilds, and microhabitats among active and passive search techniques that can be used for short-term surveys (Rödel & Ernst, 2004). All factors considered, this combination was decidedly the most effective methodology not only for conducting this short-term baseline assessment but also for establishing a feasible monitoring scheme for the continued long-term assessment of herpetofauna on Sumak Allpa.

VES and AES As much of the island as was accessible and possible was surveyed between April 22 and May 7, 2018. Using VES and AES, areas of all seven maintained trails and three convening temporary transects were searched in three, four, and five-hour blocks between the hours of 8:00- 17:15 for what were termed diurnal searches and 19:30- 1:45 for nocturnal searches for a total of 39 hours each of diurnal and nocturnal surveys. Surveys were conducted at an average speed of 2.5 meters per minute. Temperature and relative humidity were recorded at the start and finish of each survey and averaged to describe conditions at the time of each survey. Herpetofauna located within 1 meter of the edge of each side of trails and transects were searched thoroughly from the ground up to 2 meters high. Trails wider than 2 meters were searched one side at a time. A Black Diamond Spot headlamp was utilized to provide light for all nocturnal surveys. Each time an individual was located visually, a photo was taken while it remained at its perch if possible, and immediately following the individual was captured by hand if possible. Once captured, a series of 5 photos - top view, ventral view, right side view, front facial view, and bird’s eye view - was taken of each individual with additional photographs of notable morphological features taken as necessary. Once photographed, snout-vent-length (SVL) and any other notable identification features were measured using a digital caliper. Individuals unable to be handled or successfully captured were photographed to the best extent possible and described thoroughly in the field immediately after being sighted. After recording these data and other relevant observations, each individual handled was released at or near the exact site of capture. All individuals were handled with disposable latex gloves which were changed after the release of each individual and all equipment to come into contact with any given organism was sanitized after each use in order to avoid vectoring fungi and other pathogens between organisms, particularly amphibians. For these visual encounters, the time of sighting was recorded for each individual, and the location of each encounter was recorded using the offline smartphone GPS application, Maps.ME. The perch height of each individual also was measured with measuring tape and microhabitat, surrounding understory vegetation density, and habitat type of each individual were noted. Microhabitats were described in the following categories: exposed soil, mud, grass, leaf litter, leaf, branch, log, and man-made structure. Leaf litter also was further described as wet or dry and loose or compact. Understory vegetation density was defined as low, medium, or high. Habitat types were classified as river edge, high varzea, low varzea, or cabin area. River edge represented areas within about 20 meters of the edge of the Napo River. High varzea designated areas unaffected by flooding, while low varzea signified areas subject to any level of flooding during an inundation event. Cabin area described the man-made clearing of high varzea and river edge habitat on the southwest shore of the island containing the dock and cabins that is subject to the most human alteration and highest levels of human activity on the island. Acoustic encounter surveys were conducted concurrently with VES. When individuals were heard calling within about 1-2 meters of the trail or transect being searched, they were recorded for 30-60 seconds using an Olympus VN-721PC Digital Voice Recorder, holding the recorder as close to the source of the sound as possible. For each of these encounters, time of call, density of understory vegetation, and habitat type also were documented.

Identification Given the small size of Sumak Allpa and the lack of knowledge regarding the exact size and status of populations of herpetofauna on the island, no specimens were collected and preserved for identification in this study. Species encountered visually were identified instead entirely based upon the morphological species concept to the most taxonomically specific level possible using Guía Dinámica de los Anfibios del Ecuador and Guía Dinámica de los Reptiles del Ecuador from BIOWEB Ecuador, Guía de Campo de Anfibios del Ecuador, Guía de Campo de Reptiles del Ecuador, Reptiles and Amphibians of the Amazon: An Ecotourist's Guide, the Frogs of the Yachana Reserve field guide, and additional online resources such as AmphibiaWeb and BIOWEB Ecuador as necessary. Recorded calls were identified using Frogs of the Ecuadorian Amazon and online databases with species-specific recordings of calls, such as AmphibiaWeb and BIOWEB Ecuador.

Community Analysis The overall herpetofaunal community surveyed was analyzed in a variety of ways. First, all species encountered were inventoried taxonomically by order, family, and species and by their IUCN Red List of Threatened Species status. The community was then analyzed first in terms of the composition of encounters: the proportions of acoustic versus visual and nocturnal versus diurnal encounters were calculated for each species, and the percentage of overall encounters of each species was calculated to demonstrate the relative size of each population within the community. Sumak Allpa’s herpetofaunal community was then analyzed for its species composition overall and in terms of various sub-communities. Sub-communities were classified within two main categories: habitat type, which contained the river edge, high varzea, low varzea, and cabin area sub-communities, and period of activity, which was categorized as diurnal or nocturnal. The sample coverage, species richness, and species diversity were estimated for the overall community and various sub-communities through asymptotic analysis using the software iNext Online and quantified using Hill numbers. Hill numbers (or the effective number of species) are parameterized by a diversity order q, which determines the measures’ sensitivity to species relative abundances (Chao et al., 2015; see A1 in Appendix for formulas). The species richness (q = 0), Shannon diversity (the exponential of Shannon entropy, q = 1) and Simpson diversity (the inverse of Simpson concentration, q = 2), all of which are expressed in units of “species equivalents,” were calculated for the overall community, the 4 defined habitat types, and the diurnal and nocturnal communities within the overall island community. The similarity of these two types of sub-communities also was analyzed to determine the overlap of species and individuals in habitat use and hours of activity. The similarity between habitat type communities was estimated with SpadeR Online’s Multiple-Community Measures tool using following measures: Sørensen similarity index, Sørensen pairwise similarity estimates, and the Bray-Curtis similarity index. The Sørensen similarity index is a classic local species richness-based similarity measure (Chao et al., 2015) and was utilized to assess the percent of species overlap in all habitat types (see A2 in Appendix for formula). Sørensen pairwise similarity estimates are similarity estimates of the same measure but between specific pairs within the set of local communities compared and were used to evaluate species overlap in specific pairs of habitat types. The Bray-Curtis similarity index compares absolute abundances among communities and thus was used to assess the overlap of individuals in habitat types (see A3 in Appendix formula). The Sørensen similarity index and the Bray-Curtis similarity index also were used to assess the similarity and overlap of species and individuals in diurnal and nocturnal communities. For this comparison, these indices were estimated using SpadeR Online’s Two-Community Measure tool, as the Sørensen similarity index is calculated differently for comparisons of only two communities (see A4 in Appendix for formula). The community’s overall microhabitat preference was then analyzed looking at the overall community usage and species composition of each microhabitat and level of understory vegetation density.

Population Analysis of Adenomera hylaedactyla Adenomera hylaedactyla constituted a significant portion of the island’s overall herpetofaunal community. Thus, in addition to the community analysis of Sumak Allpa, the population of A. hylaedactyla, specifically, was analyzed in more depth first through the consideration of population-specific microhabitat preference. The distributions of both acoustic and visual encounters of the species among levels of understory vegetation and habitat types also were assessed to determine the population’s preferred habitat conditions for both calling and general activity. Lastly, the size distribution of individuals within the population was evaluated using snout-vent-length measurements.

Results VES and AES Inventory During the study period, 373 individuals were identified by visual encounter and 179 individuals were identified by acoustic encounter for a total of 552 individuals, representing 15 species from 5 families of the order Anura and 11 species from 7 families of the order Squamata (Table 1). Of the total of 26 distinct species, 22 were identified taxonomically to species level and 4 were identified to the genus level as distinct morphospecies. Of the 22 species identified to species level, 7 were classified as Least Concern on the IUCN Red List of Threatened Species, 5 were as Least Concern but needs updating, indicating their assessment is older than 10 years (CITE IUCN). None of reptilian species encountered on Sumak Allpa had been evaluated by the IUCN (Table 1).

Table 1. Families and species encountered during the study period, including their status on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species (LC = Least Concern, LC* = Least Concern but needs updating, NE = Not Evaluated, -- = not identified to species level), and combined number of visual and acoustic encounters. ANURA FAMILY SPECIES IUCN Status Number of Encounters Rhinella aff. margaritifera LC 1 BUFONIDAE Rhinella marina LC 2 Boana boans NE 8 HYLIDAE Dendropsophus parviceps LC* 1 Osteocephalus taurinus LC 1 Adenomera andreae LC* 86 Adenomera hylaedactyla LC 317 Adenomera sp. -- 11 LEPTODACTYLIDAE Leptodactylus knudseni LC 5 Leptodactylus mystaceus LC 59 Leptodactylus pentadactylus LC 4 MICROHYLIDAE Chiasmocleis bassleri LC* 17 Oreobates quixensis LC* 2 STRABOMANTIDAE Pristimantis altamazonicus LC* 7 Pristimantis sp. -- 2 SQUAMATA FAMILY SPECIES IUCN Status # Drepanoides anomalus NE 1 COLUBRIDAE Imantodes cenchoa NE 2 Leptodeira annulata NE 1 ELAPIDAE Micrurus lemniscatus helleri NE 1 VIPERIDAE Bothrops atrox NE 1 GEKKONIDAE Thecadactylus solimoensis NE 2 Anolis bombiceps NE 1 IGUANIDAE Anolis sp. 1 -- 1 Anolis sp. 2 -- 1 SPHAERODACTYLIDAE Pseudogonatodes guianensis NE 15 TEIIDAE Tupinambis cuzcoensis NE 3 TOTAL FAMILY SPECIES # 12 26 552

Types and Frequency of Encounters Of the 26 species observed on Sumak Allpa, 19 were encountered only visually, 3 were encountered only acoustically, and 4 were both seen and heard calling (Figure 3A). Additionally, 18 species were encountered exclusively nocturnally, 5 exclusively diurnally, and 3 were encountered both nocturnally and diurnally (Figure 3B).

(A) A. andreae (B) A. hylaedactyla Adenomera sp. A.bombiceps Anolis sp. 1 Anolis sp. 2 B.boans B. atrox C. bassleri D. parviceps D. anomalus I.cenchoa L. knudseni

Species L. mystaceus L. pentadactylus L. annulata M.l. helleri O. quixensis O. taurinus P. altamazonicus Pristimantis sp. P. guianensis R. aff. margaritifera R. marina T. solimoensis T. cuzcoensis

0% 50% 100% 0% 50% 100% Percentage of Type of Encounter Visual Acoustic Diurnal Nocturnal

Figure 3. Percentage of (A) acoustic versus visual and (B) diurnal versus nocturnal encounters for each species observed on Sumak Allpa.

Adenomera hylaedactyla, a principally nocturnal species, was encountered most frequently in both visual and acoustic surveys, accounting for 57.4% of all encounters (Figure 4). Adenomera andreae, a principally diurnal species, was the most encountered diurnal species and second most encountered species overall, accounting for 15.6% of all encounters (Figure 4). Leptodactylidae was the most encountered family in both VES and AES.

A. andreae, 15.6% A. hylaedactyla, 57.4% Adenomera sp., 2.0% A. bombiceps, 0.2% Anolis sp. 1, 0.2% Anolis sp. 2, 0.2% B. boans, 1.4% B. atrox, 0.2% C. bassleri, 3.1% D. parviceps, 0.2% D. anomalus, 0.2% I. cenchoa, 0.4% L. knudseni, 0.9% L. mystaceus, 10.7% L. pentadactylus, 0.7% L. annulata, 0.2% M.l. helleri, 0.2% O. quixensis, 0.4% O. taurinus, 0.2% P. altamazonicus, 1.3% Pristimantis sp., 0.4% P. guianensis, 2.7% R. aff. margaritifera, 0.2% R. marina, 0.4% T. solimoensis, 0.4% T. cuzcoensis, 0.5%

Figure 4. Percentage of overall encounters of each species surveyed on Sumak Allpa.

Community Composition The sample coverage of the island overall was a high estimate of 0.982, and each of the sub-communities were also estimated to be well-surveyed (Figure 5). Low varzea was the best- sampled habitat type with a sample coverage of 0.975, and the nocturnal community was estimated to be slightly better sampled than the diurnal community (Figure 5).

1 0.99 0.98 0.97 0.96 0.95 0.94 0.93

0.92 Sample Sample Coverage Estimate 0.91 0.9 Overall River Edge High Varzea Low Varzea Cabin Area Diurnal Nocturnal Sub-Community

Figure 5. Estimated sample coverage for the entire island and the 6 sub-communities of the island, where 1.00 indicates 100% sample coverage.

The overall community of herpetofauna was characterized by high species richness and low species diversity (Figure 6). Species richness of the overall community was estimated at 34.98 species equivalents, while the Shannon diversity index estimated 1.60 species equivalents, or about 2 common species in the overall community, and the Simpson diversity index estimated 0.633 species equivalents, or effectively 1 dominant species in the overall community (Figure 6).

Likewise, each habitat type demonstrated the same trend of much higher species richness than species diversity. High varzea was estimated to have the highest habitat species richness at 48.89 species equivalents, while the cabin area was the least species rich habitat estimated at only 5.93 species equivalents (Figure 6). In other words, high varzea habitats are used by the largest number of species, while the cabin area is occupied by only few species. Meanwhile, all habitat types had effectively 2 or fewer common species and 1 or fewer dominant ones, as given by Shannon and Simpson diversity, respectively (Figure 6).

q = 2 Nocturnal Diurnal Cabin Area Low Varzea High Varzea River Edge Overall

q = 1 Hill Order Hill

q = 0

0 10 20 30 40 50 60 70 Species Equivalents Figure 6. Diversity profile estimates of the overall and sub-communities of herpetofauna on Sumak Allpa in terms of species richness (q = 0), Shannon diversity (q = 1), and Simpson diversity (q = 2) (Species Equivalents ± SE).

Diurnal and nocturnal communities also had high species richness relative to species diversity (Figure 6). The nocturnal community was estimated to be more than twice as rich as the diurnal community in species with 30.10 species equivalents, yet both communities had roughly only one common species and about 1 or fewer dominant species. The Sørensen index, a richness-based similarity measure, for the comparison of all habitat types was 0.794, indicating that about 79.4% of species on Sumak Allpa can be encountered in all four of the classified habitat types (Figure 7). The pairwise similarity estimates indicate the highest levels of overlap in species use of river edge and low varzea and of high varzea and low varzea, with 31.3% of species estimated to utilize both river edge and low varzea habitats and 27.9% of species estimated to make use of both high and low varzea habitats (Figure 7). Meanwhile, the lowest level of species habitat overlap was between high varzea and the cabin area with an estimated 10.6% of species being encountered in both (Figure 7). The Bray-Curtis index, a measure for comparing species absolute abundances, estimated only 48.8% of individuals in the community make use of all four habitat type (Figure 7). 1

0.8

0.6

0.4

Similarity Similarity Estimate 0.2

0 Sørensen Edge, HVz Edge, LVz Edge, CA HVz, LVz HVz, CA LVz, CA Bray-Curtis Similarity Measure Sørensen index Sørensen pairwise similarity Bray-Curtis index

Figure 7. Estimated similarity of sub-communities based on habitat type (Edge = river edge, HVz = high varzea, LVz = low varzea, CA = cabin area) given by the classic richness-based Sørensen similarity index, richness-based Sørensen pairwise similarity estimates, and species absolute abundance-based Bray-Curtis index (Similarity Estimate ± SE).

There was very little overlap between the diurnal and nocturnal communities on Sumak Allpa. The richness-based Sørensen similarity index of the communities was 0.177, estimating that only 17.7% of species on the island could be encountered both diurnally and nocturnally (Figure 8). The abundance-based Bray-Curtis similarity index was even lower, suggesting that only about 7.6% of individuals on the island are active during both what were defined as daytime and nighttime hours for the purposes of this study (Figure 8).

0.5 0.45 0.4 0.35 0.3 0.25 0.2

0.15 Similarity Similarity Estimate 0.1 0.05 0 Sørensen index Bray-Curtis index Similarity Measure

Figure 8. Estimated similarity of diurnal and nocturnal sub-communities given by the Sørensen similarity index and Bray-Curtis index (Similarity Estimate ± SE).

Microhabitat and Understory Vegetation Density Preference In visual encounter surveys, 339 individuals representing 12 different species were encountered in leaf litter, making it the most utilized microhabitat by the island’s community (Figure 9). More specifically, leaf-litter dwelling individuals exhibited preferences for loose over compact leaf litter and dry over wet leaf litter (Figure 9). The next most preferred microhabitat was leaves, upon which 16 individuals of 8 different species were encountered (Figure 9).

MMS A. andreae A. hylaedactyla Adenomera sp. Log A. bombiceps Anolis sp. 1 Anolis sp. 2 Branch B. atrox C. bassleri D. parviceps D. anomalus I.cenchoa L. mystaceus Leaf L. annulata M.l. helleri O. quixensis Grass O. taurinus P. altamazonicus Pristimantis sp. P. guianensis R. aff. margaritifera R. marina Mud T. solimoensis T. cuzcoensis Soil

WC Microhabitat DC WL DL

0 20 40 60 80 100 120 140 160 180 Number of Encounters Figure 9. Community use of microhabitats by number of visual encounters in terms of species composition (Soil = exposed soil, MMS = man-made structure, DL = dry loose leaf litter, WL = wet loose leaf litter, DC = dry compact leaf litter, WC = wet compact leaf litter).

High density understory vegetation was most preferred by the community for both calling and general dwelling, followed by medium density and low density, respectively (Figure 10).

200 180

160 Visual Acoustic 140 120 100 80 60

NumberEncounters of 40 20 0 Low Medium High Understory Vegetation Density Figure 10. Community preference for level of understory vegetation density in terms of number of visual and number of acoustic encounters for each level. Additionally, the widest array of species was harbored by high density understory vegetation with 19 different species encountered, versus 16 in medium density and 6 in low density (Figure 11). Seven of the species found in high density understory vegetation were found exclusively in that level of density of understory vegetation.

High

Medium

A. andreae A. hylaedactyla Adenomera sp. A.bombiceps Anolis sp. 1 Anolis sp. 2 B. atrox B.boans C. bassleri D. anomalus D. parviceps I.cenchoa

Understory VegetationDensity L. annulata L. knudseni L. mystaceus L. pentadactylus Low M.l. helleri O. quixensis O. taurinus P. altamazonicus P. guianensis Pristimantis sp. R. aff. margaritifera R. marina T. cuzcoensis T. solimoensis

0 50 100 150 200 250 300 Number of Encounters Figure 11. Community preference for level of understory vegetation density by number of overall encounters in terms of species composition.

Population Analyses of Adenomera hylaedactyla Accounting for 57.4% of all visual and acoustic encounters, Adenomera hylaedactyla was by far the most frequently observed species on the island with the highest relative abundance (Figure 4). The species is primarily nocturnal; however, of the 317 overall encounters, it was encountered visually 4 times in the last 30 minutes of what were considered diurnal searches for the purposes of this study. The population of A. hylaedactyla followed many of the same trends for the community overall. Individuals among the population preferred leaf litter habitats - dry over wet leaf litter and loose over compact leaf litter, in addition to showing overall preference for high density understory vegetation over medium and low density (Figure 9; Figure 11). In terms visual versus acoustic encounters, high density understory vegetation was preferred for calling sites, but there were slightly more visual encounters in medium density than high density understory vegetation (Figure 12). The population also showed differences in the number of visual versus acoustic encounters among habitat types (Figure 13). High varzea was the most preferred habitat for both calling and general activity, but there were more acoustic encounters than visual encounters in low varzea areas and more visual than acoustic encounters at the river edge habitat (Figure 13). Not a single vocalization of the species was recorded in the cabin area, although calls could be heard from forest areas within the vicinity of it (Figure 13).

120

100 Visual Audio

80

60

40 NumberEncounters of 20

0 Low Medium High Understory Vegetation Density Figure 12. Distribution of Adenomera hylaedactyla visual and acoustic encounters among understory vegetation densities.

100

90 Visual Audio 80 70 60 50 40

30 NumberEncounters of 20 10 0 River Edge Low Varzea High Varzea Cabin Area Habitat Type Figure 13. Distribution of Adenomera hylaedactyla visual and acoustic encounters among habitat types.

The body size of individuals in the population ranged from 5.01 mm to 27.60 mm and on average was 19.75 mm (Figure 14). The average body size of Adenomera hylaedactyla is 23.5 mm for males and 25.6 mm for females (Angulo et al. 2003; Aichinger 1992), which were the 73rd and 87th percentile, respectively, in the population encountered on Sumak Allpa (Figure 14).

Figure 14. Distribution of body size in terms of snout-vent-length of Adenomera hylaedactlya individuals encountered on Sumak Allpa.

Discussion Island Biogeography Theory proposes that the number of species of any island reflects a balance between the rate at which new species colonize it and the rate at which populations of established species decline and become extinct posits that the larger and/or closer to the mainland an island is, the more species it will be able to support (MacArthur & Wilson, 2016). Thus, a small island close to mainland, such as Sumak Allpa, should in theory be able to support a medium to high level of species richness but very few individuals within each. Considering the trends of high species richness and low species diversity in the diversity profile estimates of the community surveyed in the current study, the herpetofaunal assemblage on Sumak Allpa appears to be a case in which Island Biogeography Theory holds true. This conclusion, however, should not be made definitively without the consideration of a variety of factors. First, although the methodology of combining VES and AES for this study was effective in detecting a large number of species in a wide range of niches across multiple taxa, including a number of species that would not have been registered if only a visually- oriented technique had been applied, there was still bias in the species the methodology encountered. Because only the understory and visible areas of the forest floor could effectively searched, aquatic species, fossorial species, and arboreal species dwelling above 2 meters, especially non-vocalizing species, were heavily biased against in this study. Additionally, because surveys were conducted on the maintained trails and transects of the island, the study design also was biased against species particularly sensitive to human use impacts. Furthermore, as in many active search techniques, species encountered are limited by number of observers and observer ability, so cryptic species may be detected significantly less, if detected at all, and species that dwell in open areas or have loud and highly distinguishable calls may be detected significantly more. Thus, in order to generate a complete species inventory of the island, future studies should be conducted in areas both on and off trails using multiple observers with experience in herpetofaunal surveying and also consider the inclusion of additional microhabitat- specific search techniques to account for species biased against in the methodology of this study. Though the sample coverage estimates reflected effective and near-complete sampling of Sumak Allpa’s herpetofaunal community, a variety of observed field conditions and other factors suggest these estimates may not reflect the true coverage of sampling. The study, for example, was conducted over a period of only 16 consecutive days all in the same season, and amphibian and reptile activity can vary temporally, resulting differences in the abundance and number of species detected in different seasons and even at different times within one season (Menin, Waldez, & Lima, 2008). There also was relatively variation in rainfall, temperatures, and percent humidity throughout the period of study, and all of these factors are known to affect herpetofaunal activity (Paladino, 1985; Brown & Shine, 2002). Furthermore, by giving rise to cues such as light intensity, geomagnetism, and gravity, lunar cycles have been associated with the reproductive phenologies (including mating vocalizations) of a number of anuran and urodele species to different effects (Grant, Chadwick, & Halliday, 2009). Thus, the full moon occurring in the middle of the study also may have played a role in the activity and detectability of species on Sumak Allpa. Inundation also may have influenced the abundance and number of species detected. Differences in the number and types of anuran vocalizations heard before and after flooding were observed informally during surveying; however, inundation occurred too early in the study period for these differences to be effectively quantified and analyzed. Any number of these variables could have influenced the high number of Adenomera hylaedactyla and Adenomera andreae individuals detected and/or the low number of encounters of other species. Therefore, under the consideration of all of these factors, more long-term future studies should be conducted throughout different times of year and under a wider array of conditions, not only to account for the potential impacts of temporality, climate, and lunar cycles on the composition of the island’s herpetofaunal community but also to investigate how each of these variables may influence specific populations within it. These factors and potential limitations aside, a number of important conclusions still can be made about the composition, activity, and habitat use of the island’s herpetofaunal community. As previously mentioned, the island supports a high level of species richness relative to species diversity, and although this trend was consistent across habitat types, species richness was not the same for each habitat’s community. High varzea, for instance, had much higher species richness than the river edge, low varzea, and cabin area communities, indicating it may provide higher resource quality, quantity, and/or accessibility to a wider variety of species and support a wider variety of niches than other habitats on the island. Additionally, the cabin area demonstrated the lowest species richness and diversity, suggesting trends opposite to high varzea in terms of resource and niche availability and also that human activity may severely inhibit the habitat from supporting large populations and numbers of species. The similarity indices of communities within these habitats also serve to characterize much of the habitat use of the island’s herpetofaunal community. The Sørensen index score of 0.794 indicates a high level of overlap in the species utilizing all of the island’s habitats. This significant overlap not only is indicative of the small size of the island and contiguity of its habitats but also suggests that a high percentage of the island’s species are habitat generalists. The pairwise similarity estimates also help characterize the community’s use of specific habitats. The higher percentages of overlap of river edge with low varzea habitat and high varzea with low varzea habitat are to be expected, given the river edge and inundated low varzea both provide access to water, which is necessary for the reproduction of many anuran species, and low varzea can be very similar to high varzea habitat when it is not inundated. Furthermore, the richness-based Sørensen similarity index was higher than the abundance-based Bray-Curtis similarity index, signifying that there is less overlap in habitat use by specific individuals within populations than there is by overall species. This relationship possibly suggests that although a species may be able to utilize more than one habitat, not all individuals in its population necessarily do. Ultimately, the composition of the herpetofaunal community did vary among habitat types, but understanding the exact causes of this variation will require further investigation. Future studies, therefore, should investigate more of the specific shared versus distinguishing characteristics of each of these habitats in terms of vegetation cover and type, prey and other resource diversity and availability, microclimate and microhabitat variation, and even geomorphology, as all of these factors have been evidenced to affect herpetofaunal assemblages in other Amazonian communities (Doan & Arriaga, 2002; Deichmann, 2009). The relationships between diurnal and nocturnal communities also provide important characterizations of the herpetofaunal community composition of Sumak Allpa. The nocturnal community had more than double the species richness than the diurnal community; however, the Sørensen similarity index indicated a small percentage of overlap in species between these communities, and the Bray-Curtis similarity index demonstrated an even smaller percentage of overlap in individuals. This apparent species richness and lack of overlap signifies the importance of continuing to monitor herpetofauna during all times of day in order to best conserve the entire community of herpetofauna on the island. Additionally, the possible misrepresentation of crepuscular species as nocturnal or diurnal species suggests that future analysis of communities in terms of periods of activity should be done with more specificity, blocking surveys during more and different hours of the day to determine more specific hours of activity for assemblages and specific populations within the overall community. The trends in microhabitat and understory vegetation density use by the community also can serve to guide future studies. In terms of microhabitat, leaf litter appeared to be the preferred by the largest portion of the community, and dry and loose leaf litter was preferred over wet and compact leaf litter. Given the significance of the microhabitat to so many individuals on the island and the limitations of using only qualitative descriptions to classify leaf litter, further analysis of more quantitative leaf litter characteristics with respect to herpetofaunal assemblages would contribute greatly to the understanding of the herpetofaunal community of Sumak Allpa, Studying small invertebrate communities inhabiting the leaf litter may also be beneficial to understanding different herpetofaunal populations and how and why the leaf litter supports them differently, especially since other Amazonian studies have demonstrated significant differences in resource utilization and guild structure among leaf-litter dwelling species of frogs and lizards (Vitt & Caldwell, 1994). Likewise, a further understanding of the relationship between understory vegetation density and herpetofaunal assemblages would benefit from a more quantitative analysis of said vegetation, its composition, and potentially associated characteristics that differentiate it from medium and low density understory vegetation other than visibility by predators, such as microclimate and prey diversity and availability. While the population of Adenomera hylaedactyla in the community was analyzed briefly in this study, there was no conclusive evidence for why it was so much more abundant than all other species encountered on Sumak Allpa. Though there was evidence that they are able to occupy all habitat types with all levels of understory vegetation density, this does not explain their proliferation, as other, less-abundant species also demonstrated these trends. Based off the observed population trends and observations of other investigations of the species, a variety of hypotheses may explain the high number of individuals in this population relative to other species on the island. The first of these hypotheses is that A. hyladactyla was significantly more influenced than all other species by one or more of the aforementioned biotic and abiotic factors influencing frog activity, such as temporality, climate, lunar cycle, and inundation. There also exists the possibility that they may be able to consume a wider variety of prey or that they may have more of their type of prey available to them than other species on the island. They also may be significantly less sensitive than other species to human activity and thus were more likely than other species to be encountered along the island’s maintained trails. Increased visual detectability compared to other species, though less likely than the aforementioned hypotheses, is also another possible explanation for the high frequency of their encounters, and any number of these hypotheses could be tested simply with any of the aforementioned future study suggestions for the community by simply changing their scope to the population. Another hypothesis is that the population of A. hylaedactlya is actually an assemblage of multiple morphs of the species, subspecies, or even distinct species. A study conducted in the Peruvian Amazon Basin by Angulo, Cocroft, & Reichile (2003) summarized how the genus Adenomera has been a difficult group for systematic studies and investigated A. andreae and A. hylaedactyla, the two most encountered species on Sumak Allpa. The researchers examined advertisement calls in relation to the frogs’ morphological characteristics and determined significant enough differences in the morphologies and acoustic parameters of the calls of associated individuals to indicate potentially four sympatric species derived from A. hylaedactyla existing at the study site. Given subtle differences in morphological features of Adenomera hylaedactyla were observed among individuals in Sumak Allpa’s population, a similar study to that of Angulo, Cocroft, & Reichile (2003) may be merited on the island. Finally, it also could be proposed that Sumak Allpa has the highest numbers of individuals of small species and lowest numbers of individuals of large species because it is experiencing a phenomenon known as excess density compensation. The theory posits that island assemblages could be partitioned differently (few species or smaller individuals) from mainland sites without differing in aggregate biomass (Rodda & Dean-Bradley, 2002). Such “excess density compensation” may be understood as either a lack of interference competition, a lack of overexploitation, or a release from predation on these islands (Case, Gilpin, & Diamond, 1979; Wright, 1980). Lack of interference competition means that this overcompensation of biomass density is caused by exclusion of more efficient competitors from some portion of the resource spectrum by inefficient species, allowing species-poor island populations or assemblages to harvest resources more efficiently and support higher total population densities than species-rich mainland communities (Wright, 1980). Resource overexploitation occurs when consumers are so efficient on the mainland that their resource abundances are reduced to the point that consumer abundances also must decline until the consumer efficiency declines to the point where resource abundances stop being reduced enough to also stop reduction of consumer abundances (Wright, 1980). If this overexploitation occurs on the mainland but not the island, species-poor islands may support higher resource abundances and higher total population densities of consumers than the species- rich mainland (Wright, 1980). Lastly, release from predation indicates that islands containing fewer predators than corresponding mainland sites would allow for higher prey densities on islands than the mainland (Wright, 1980). This final hypothesis is by far the most involved and also probably the least likely, especially given much of the debate surrounding the concept of excess density compensation in general, yet there may be merit in investigating it as a potential alternative if the other hypotheses do not account for the high numbers of A. hylaedactyla and other small-bodied species on Sumak Allpa. Ultimately, given its high density and abundance on Sumak Allpa, A. hylaedactyla should be a priority species for population studies to determine why the island supports so many individuals compared to other species. Population studies, nevertheless, should not be limited to this species alone. There is merit in the assessment of all populations of the island, especially considering the number of outdated IUCN Red List listings of species and unevaluated species encountered on the island. Though comprehensive studies of global and national assemblages of herpetofauna are necessary to generate awareness of the world’s significant amphibian and reptile declines and call to action the large-scale conservation efforts needed to combat them, these studies ultimately are informed by the aggregation of small-scale studies monitoring local communities and populations. Despite the immense species richness and diversity of herpetofauna across Ecuador and the Neotropics, the study of specific herpetofaunal communities and populations overall is pretty lacking. Thus, gaining a better understanding of the local interactions, functions, behaviors, and ecologies of specific species, populations, and communities of herpetofauna in threatened regions such as the western Amazon and the Neotropics is one of the biggest strides that needs to be made for the conservation of the immense richness and diversity of these regions. Thus, especially considering the lack of evaluation and continued monitoring of the majority of species encountered at Sumak Allpa by the IUCN – the global authority on the status of the natural world – any investigation filling one of the many knowledge gaps of herpetofauna on Sumak Allpa is merited, warranted, and valuable work for the conservation of herpetofauna on the island and in the region overall.

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Appendix

A1. Hill’s number of order q, q ≥ 0:

and

A2. Sørensen similarity index for multiple community measures:

A3. Classic Bray-Curtis similarity index:

A4. Sørensen similarity index for the special case of two communities: