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We analyzed 72 specimens from the Arauca (71) and Casanare (1) departments in the Orinoco region of Colombia. The specimens belong to 10 genera and 18 species of vespid wasps. Four species are reported for the first time for the region and 14 are new records for the Arauca department. There is a likely new record of Stenodynerus cf. australis for the Neotropical region. Resumen Analizamos 72 especímenes colectados de los departamentos de Arauca (71) y Casanare (1) en la región de la Orinoquía. Estos pertenecen a 10 géneros y 18 especies de avispas. Cuatro especies son nuevos registros para la región y 14 son nuevas para el departamento de Arauca. Hay también un posible nuevo registro de Stenodyneus cf. australis para la región Neotropical.

Introducción: Las hormigas son uno de los grupos taxonómicos más abundantes y diversos, además su fidelidad ecológica les permite desempeñar roles indispensables para el funcionamiento adecuado de los ecosistemas terrestres. Objetivo: evaluar la dinámica estacional de la biodiversidad (riqueza y abundancia) de la comunidad de hormigas asociadas a fragmentos de bosque y la sabana inundable circundante (sabana-borde-bosque) en el municipio de Arauca (Colombia). Métodos: en un transecto lineal se recolectaron hormigas en siete puntos de muestreo usando trampas de caída, recolecta directa y saco mini-winkler para hojarasca en ocho fragmentos de bosque y la sabana circundante. Estimadores no paramétricos y el índice de complementariedad se utilizaron para describir la estructura de la comunidad de hormigas. Las estaciones climáticas (sequía y lluvias) y los ambientes (sabana inundable, borde y bosque) se compararon utilizando la riqueza y abundancia de especies. La relación de las especies de hormigas por cada punto de muestreo se evaluó con un análisis de escalamiento multidimensional no métrico (NMDS) y los atributos de los fragmentos de bosque se relacionaron con la riqueza de especies a través de un análisis de correspondencia canónica (CCA). Resultados: se recolectaron 30 496 especímenes correspondientes a 104 especies, 37 géneros y ocho subfamilias. Los géneros mejor representados fueron: Pheidole, Camponotus, Solenopsis y Dolichoderus. Los estimadores de riqueza no paramétricos mostraron que la comunidad de hormigas oscila entre 107 y 119 especies. No se detectaron diferencias en la riqueza y abundancia de especies respecto a las estaciones climáticas. La riqueza de especies fue mayor en el bosque respecto a la de la sabana y el borde. El resultado del ACC presentó una variación total explicada por el 62.7 % que muestra la relación entre las especies y los atributos de los fragmentos de bosque. Conclusiones: no se detectaron diferencias en la riqueza y abundancia de especies entre las estaciones seca y lluviosa, sugiriendo que las especies son residentes permanentes del área de estudio, por lo que deben existir mecanismos que permitan a ciertas especies de hormigas sobrellevar la estación lluviosa. Las variables del fragmento área, perímetro y compactación presentan una relación directa con la riqueza de especies, mientras que la dimensión fractal tiene una relación inversa sobre la riqueza de especies que el fragmento alberga. Este trabajo amplía el conocimiento de las especies de hormigas presentes en el norte de la Orinoquia colombiana.

Se registran 18 novedades para la flora vascular de Colombia a partir de ejemplares recolectados en la región de la Orinoquia. Los nuevos registros corresponden a: Duguetia riberensis Aristeg. ex Maas & Boon, Trigynaea duckei (R. E. Fr.) R. E. Fr. (Annonaceae); Tassadia medinae (Morillo) Morillo (Apocynaceae); Jaracanda orinocensis Sandw. (Bignoniaceae); Polycarpaea corymbosa (L.) Lam. var. brasiliensis (Cambess.) Chodat & Hassl. (Caryophyllaceae); Murdannia burchellii (C. B. Clarke) M. Pell. y M. aff. triquetra (Wall. ex C. B. Clarke) G. Brückn (Commelinaceae); Enterolobium barinense L. Cárdenas & Rodr.-Carr., Machaerium tovarense Pittier, Muellera crucisrubierae (Pittier) M. Sousa y Tachigali davidsei Zarucchi & Herend. (Leguminosae), Nectandra bartlettiana Lasser (Lauraceae); Lindernia brachyphylla Pennell ex Steyerm. (Linderniaceae); Campomanesia aromatica (Aubl.) Griseb. (Myrtaceae); Christiana africana DC. (Malvaceae); Dulacia cyanocarpa Sleumer (Olacaceae); Phyllanthus microphyllus Kunth (Phyllanthaceae) y Gouania wurdackii Steyerm. (Rhamnaceae). Estas especies fueron recolectadas en los departamentos de Arauca y Vichada. Se discuten aspectos relacionados con la taxonomía y nomenclatura de estos nuevos registros, su distribución geográfica, sus afinidades con la flora presente en la Orinoquia venezolana y regiones con características florísticas similares. Se agrega una reseña histórica de las exploraciones en los llanos colombianos.

RESUMEN Mediante censos se documentó el recambio en la composición florística asociado al régimen de lluvias en comunidades de las sabanas de Arauca (Arauca, Colombia). Además, se cuantificó la abundancia relativa y el Índice de Valor de Importancia (IVI) de las especies en eventos de muestreo bimestrales a lo largo de un año. Se usaron transectos lineales con once puntos y once cuadrantes de 1 m2. Se registraron 110 especies y se obtuvo una correlación positiva entre la precipitación mensual y la abundancia de individuos, acompañada de un aumento del 85,7 % en la riqueza de especies en los meses de lluvias. Debido al mayor número de especies (96) la equitatividad de la comunidad fue mayor en el periodo de lluvias en tanto que, de las 57 especies de la época de sequía hubo dominancia de especies como Hydrolea spinosa, Melochia spicata, Peltaea sessiliflora, Cyperus luzulae, Acroceras zizanioides y Andropogon bicornis. El periodo de lluvias tuvo 53 especies exclusivas mientras que catorce lo fueron durante el periodo seco. Este estudio resalta la alta diversidad botánica que existe en las sabanas de la Orinoquia. ABSTRACT Changes in the floristic composition in flooded savannas in Arauca (Arauca, Colombia) were described and correlated with annual rain patterns. We surveyed the vegetation to determine species richness, relative abundances and the Importance Value Index (IVI) using eleven-point line transects and eleven 1 m2 plots every two months for a year. 110 species were recorded, and there was a positive correlation between the monthly precipitation and the abundance of individuals in the vegetation community. The higher values of species richness (96) occurred during the wet season compared to the dry season species richness (57). Also, the wet season rank abundance curve had higher evenness compared to the dry season curve. Species that were dominant during the dry season included Hydrolea spinosa, Melo-chia spicata, Peltaea sessiliflora, Cyperus luzulae, Acroceras zizanioides, and Andropogon bicornis. 53 species were exclusive to the wet season and fourteen to the dry season. This study shows the high botanic biodiversity that can be found in the Orinoco savannas.

Resumen El orden Lepidoptera es uno de los taxones más diversos y conocidos de insectos. Sin embargo, hay aspectos ecológicos de este grupo que se han investigado poco en la Orinoquia colombiana. En el estudio se documenta la dinámica temporal de la riqueza y la abundancia de mariposas frugívoras en la sabana inundable del municipio de Arauca y su relación con las variables climáticas de temperatura y precipitación. El muestreo se realizó a 9 km de la cabecera municipal de Arauca, usando seis trampas Van Someren Rydon durante cinco días al mes a lo largo de 24 meses. Se registraron 227 individuos de 21 especies. Los estimadores no paramétricos de diversidad indicaron que el muestreo tuvo una representatividad de 87,9 a 91,2 % de las mariposas frugívoras del área. Los análisis de agrupamiento y de similitudes (ANOSIM) indicaron que la respuesta de la comunidad de mariposas corresponde al régimen unimodal de precipitación de la Orinoquia, con mayor riqueza de especies y abundancia durante los meses de lluvia. Se estableció que las temperaturas en los días de muestreo tuvieron un efecto negativo en las tasas de captura. Este trabajo representa la primera aproximación a la dinámica temporal de la riqueza y la abundancia de lepidópteros y su relación con las variables climáticas en el norte de la Orinoquia colombiana. Abstract The insect order Lepidoptera is one of the most diverse and well known. However, the ecological aspects of this group in the Colombian Orinoquia have been poorly investigated. In this study, we documented the temporal dynamics of species richness and abundance of fruit-feeding butterflies in the flooded savanna of the municipality of Arauca. These temporal dynamics were related to the climatic variables of temperature and precipitation. The study was conducted near the town of Arauca (9 km). We sampled for five days per month for 24 months. We captured 227 butterflies from 21 species representing between 87.9 % and 91.2 % of fruit-feeding butterflies in the study area as shown by the non-parametric estimators of diversity. Cluster and ANOSIM analyses evidenced a positive relationship with rainfall resulting in greater species richness and abundances during the rainy season. There was a negative correlation between the temperatures during sampling days and the number of butterflies captured. This study is the first approach to the temporal dynamics of the richness and abundance of Lepidoptera and their relationship with climatic variables in the northern Colombian Orinoquia.

Se revisaron 56 ejemplares de mariposas de la familia Papilionidae colectados esporádicamente en el norte de la Orinoquia colombiana en municipios pertenecientes a los departamentos de Arauca, Norte de Santander y Casanare, en un rango altitudinal entre los 120 y 494 msnm. Los especímenes corresponden a tres géneros, siete especies y siete subespecies siendo las más abundantesBattus polydamas polydamasyParides eurimedes arriphuscon 15 y 12 individuos, respectivamente. Las siete especies identificadas corresponden al 11,5% de las 61 reportadas para Colombia y al 29,2% de las 24 especies de Papilionidae registradas para toda la región Orinoquia. A nivel regional la riqueza de Papilioniade en Arauca es igual a la reportada en una localidad en el Meta (siete sp.) y menor que la del departamento de Casanare (nueve sp.). Reportamos la ampliación de la distribución geográfica de cuatro subespecies a nivel regional. Fifty six specimens of Papilionidae butterflies were non-systematically collected and are documented from the northern part of the Colombian Orinoquia. Specifically, specimens were collected in Arauca, Casanare, and Norte de Santander departments in an altitudinal gradient between 120 and 494 m.a.s.l. The specimens belong to three genera, seven species and seven subspecies being the most abundantBattus polydamas polydamasandParides eurimedes arriphuswith fifteen and twelve individuals respectively. The seven species identified correspond to 11.5 % of the 61species reported to Colombia and 29.2% of the 24 species of this family registered for the whole Colombian Orinoco region. At regional scale, the species richness of Papilionidae in Arauca equals t reported in a locality of Meta department (seven sp.) and lesser than the department of Casanare (nine sp.). For four subspecies, the collection localities imply the enlargement of their previously reported geographical distribution, at regional spatial scale.

The endangered iguana Cyclura cornuta stejnegeri is endemic to Mona Island, Puerto Rico. Factors accounting for its protected status include low adult densities and relatively low abundance of juveniles. We studied the spatial ecology, territoriality, and philopatric behavior along a gradient of human- disturbed areas to increase our understanding of its unusual demography. We used the minimum convex polygon (MCP) method to estimate the home range of radiomarked iguanas, the degree of inter- and intrasex home-range overlap, and the temporal patterns of space use by 42 iguanas (19 males and 23 females, including 4 juvenile individuals) during the nonbreeding (October-November) and mating season (June) at three Mona Island localities with different levels of human disturbance. Juvenile iguanas had larger home ranges and move across the home ranges of several adults. Adult males had larger home ranges than females and no significant temporal differences in size or pattern of usage (Cole index) were detected between the study periods. Females, despite reducing their home-range size during the mating season, changed the usage patterns, resulting in increased interactions with neighboring males. Home-range overlap was minimal between males, followed by female-female overlap and maximal between males and females. Our results suggest that Mona Island iguanas are highly territorial throughout the year; particularly males in the mid- and undisturbed areas where almost all home-range areas appear to be equivalent to the defended territory. In the most disturbed area, where supplemental feeding by humans exists, home ranges are smaller and there is larger intersex home-range overlap. Previously, the low density of the population was attributed to lack of recruitment into adult stages due to predation of juveniles by nonnative mammals. However, the high levels of territoriality documented in this study may be an additional factor explaining the low densities exhibited by this population. Our data suggest that the three study sites may be at or close to carrying capacities for males, because there appear to be no vacant areas for additional males. Furthermore, the large and highly overlapping home ranges exhibited by four juvenile iguanas suggest that they are or will become floaters in search of unoccupied space.

The population of the endangered iguana Cyclura cornuta stejnegeri , endemic to Mona Island (Puerto Rico), is characterized by a low density and an adult-skewed age distribution. In this study we measured space use patterns in nine adult iguanas (five males and four females) during the non-breeding period in an undisturbed environment in order to determine to what extent spatial and territorial behavior contributes to the observed low density. Minimum Convex Polygon and the 50% and 90% Kernel methods were used to estimate the home range of radio marked iguanas. Male-female home range overlap was extensive while male-male overlap was minimal. Females were distributed randomly in the study area, while males exhibited a regular spacing pattern. The lack of home range overlap among males and their regular distribution pattern suggests that males of the Mona Island iguana are highly territorial, and that their home range areas appear to be equivalent to territories. Previous studies had attributed the low iguana densities on Mona Island to the scarcity of mid-size iguanas that precluded recruitment into the adult stages. The high levels of territoriality among Mona Island iguana males documented in this study suggests an additional factor that may explain the low densities in this population. Our data suggest that male carrying capacity may have been reached at Mona Island since there appear to be no "vacant" areas for additional male territories.

We isolated and characterized 11 microsatellite loci in the Mona Island iguana (Cyclura cornuta stejnegeri). Eleven loci exhibit moderate to high allelic diversity (two to 12 alleles, mean = 4.5) and polymorphism (mean observed heterozygosity, 0.56; range, 0.26 to 0.78) in 41 adults. This marker set has low probability of identity and high parentage exclusion power and will be suitable for studies of paternity, social organization and relatedness in this species.

MB and MR were funded by a grant from the Esmee Fairbairn Foundation, BC by the Rufford Foundation. North American and Mexican species assessments were funded by the Regina Bauer Frankenberg Foundation for Animal Welfare. Species assessments under the Global Reptile Assessment (GRA) initiative are supported by: Moore Family Foundation, Gordon and Betty Moore Foundation, Conservation International, Critical Ecosystem Partnership Fund (CEPF), and European Commission. Additional acknowledgements are included in the online supplementary material. The assessment workshop for Mexican reptiles was kindly hosted by Ricardo Ayala and the station personnel of the Estacion de Biologia Chamela, Institut de Biologia, Universidad Nacional Autonoma de Mexico. Workshop and logistical organisation of the Philippines assessments was provided by the Conservation International Philippines Office, in particular Ruth Grace Rose Ambal, Melizar V. Duya and Oliver Coroza. Workshop and logistical organisation for the European Reptile and Amphibian Assessments was provided by Doga Dernegi, in particular Ozge Balkiz and Ozgur Koc. Workshop and logistical organisation for assessments of sea snakes and homalopsids was provided by the International Sea Turtle Symposium and Dr. Colin Limpus (Australian Government Environmental Protection Agency). Special thanks to Jenny Chapman (EPA) and Chloe Schaub le (ISTS). Thank you also to Dr. Gordon Guymer (Chief Botanist Director of Herbarium) for accommodating us at the Herbarium in the Brisbane Botanical Gardens, and Mark Read and Kirsten Dobbs (Great Barrier Reef Marine Parks Association) and Dave Pollard and Brad Warren (Ocean Watch Australia) for institutional support. Mohamed Bin Zayed Species Conservation Fund, Conservation International Madagascar and the Darwin Initiative contributed to funding the costs of the Madagascar reptile workshop., Effective and targeted conservation action requires detailed information about species, their distribution, systematics and ecology as well as the distribution of threat processes which affect them. Knowledge of reptilian diversity remains surprisingly disparate, and innovative means of gaining rapid insight into the status of reptiles are needed in order to highlight urgent conservation cases and inform environmental policy with appropriate biodiversity information in a timely manner. We present the first ever global analysis of extinction risk in reptiles, based on a random representative sample of 1500 species (16% of all currently known species). To our knowledge, our results provide the first analysis of the global conservation status and distribution patterns of reptiles and the threats affecting them, highlighting conservation priorities and knowledge gaps which need to be addressed urgently to ensure the continued survival of the world’s reptiles. Nearly one in five reptilian species are threatened with extinction, with another one in five species classed as Data Deficient. The proportion of threatened reptile species is highest in freshwater environments, tropical regions and on oceanic islands, while data deficiency was highest in tropical areas, such as Central Africa and Southeast Asia, and among fossorial reptiles. Our results emphasise the need for research attention to be focussed on tropical areas which are experiencing the most dramatic rates of habitat loss, on fossorial reptiles for which there is a chronic lack of data, and on certain taxa such as snakes for which extinction risk may currently be underestimated due to lack of population information. Conservation actions specifically need to mitigate the effects of human-induced habitat loss and harvesting, which are the predominant threats to reptiles., Esmee Fairbairn Foundation, Rufford Foundation, Regina Bauer Frankenberg Foundation for Animal Welfare, Moore Family Foundation, Gordon and Betty Moore Foundation, Conservation International, Critical Ecosystem Partnership Fund (CEPF), European Commission Joint Research Centre, Zayed Species Conservation Fund, Conservation International Madagascar, Darwin Initiative

Assessing the status of tropical dry forest habitats using remote sensing technologies is one of the research priorities for Neotropical forests. We developed a simple method for mapping vegetation and habitats in a tropical dry forest reserve, Mona Island, Puerto Rico, by integrating the Normalized Difference Vegetation Index (NDVI) from Landsat, topographic information, and high-resolution Ikonos imagery. The method was practical for identifying vegetation types in areas with a great variety of plant communities and complex relief, and can be adapted to other dry forest habitats of the Caribbean Islands. NDVI was useful for identifying the distribution of forests, woodlands, and shrubland, providing a natural representation of the vegetation patterns on the island. The use of Ikonos imagery allowed increasing the number of land cover classes. As a result, sixteen land-cover types were mapped over the 5500 ha area, with a kappa coefficient of accuracy equal to 79%. This map is a central piece for modeling vertebrate species distribution and biodiversity patterns by the Puerto Rico Gap Analysis Project, and it is of great value for assisting research and management actions in the island.

The endemic Mona Island Iguana, Cyclura cornuta stejnegeri, is considered endangered, and exhibits relatively low population numbers and reduced recruitment of juveniles to adults. A headstarting program was initiated in 1999 to increase the effective population number. Two groups of headstarted iguanas were released in April and August 2002, after reaching a target size. Most of the released iguanas have since been observed to be active and in good health. Two females bred in 2004, the first certain record of reproduction by headstarted Cyclura iguanas in the wild. Eight radiotracked individuals had large dispersal ranges, with mean Minimum Convex Polygon (MCP) of 10.7 ha (range 2.6-22.2 ha) and mean distances covered of 288 m (range 471-6396 m).We discuss the future development of the headstarting program for Mona Island iguanas.

With a total area of 8900 km2, Puerto Rico is the smallest of the Greater Antilles. It is divided in three physiographic regions or areas of relief: the mountainous interior, the karst region, and the coastal plains and valleys. The island comprises six ecological life zones: subtropical dry forest, subtropical moist forest, subtropical wet forest, subtropical rain forest, lower montane wet forest and lower montane rain forest. The herpetofauna of Puerto Rico consists of 25 species of amphibians (19 native, six introduced) and 56 species of reptiles (52 native, four introduced). The goal of this paper is to describe some of the present studies directed towards the conservation of Puerto Rican herpetofauna. Eleutherodactylus karlschmidti, E. jasperi and E. eneidae have not been seen or heard since 1976, 1981 and 1990, respectively, and are probably extinct. Since 2000, the potential causes of amphibian declines in Puerto Rico have been studied, and a synergistic interaction between climate change (increased dry periods) and disease (chytridiomycosis) have been proposed as an explanation for the patterns observed. Recovery efforts for Peltophryne lemur include a captivebreeding program, reintroductions island-wide educational outreach, protection and restoration of existing habitat, and the creation of new breeding ponds. Among reptiles, the first conservation efforts to protect Epicrates inornatus were limited to trying to halt collection and hunting. However, current strategies to preserve the boa include gathering basic biological information, habitat conservation, and educational outreach. Recent efforts for the conservation of Trachemys s. stejnegeri combine three research approaches to clarify the status of local populations: a mark-recapture-release study, field monitoring of reproductive activity (i.e., nocturnal patrolling to identify nesting activity), and field assessment of the potential impact of introduced species, particularly identification of predatory species and exotic turtles. Recovery initiatives for Cyclura stejnegeri include management of invasive mammals, a headstart program for hatchling iguanas, and the assessment of the etiology of a condition causing blindness in adult iguanas. A reforestation project aimed at recovering a local herpetofaunal assemblage after disturbances in a limestone valley in northern Puerto Rico is discussed. As population sizes of common colonizers such as Eleutherodactylus and Anolis increased, larger forest-interior and predatory species like Epicrates inornatus, Alsophis portoricensis and Anolis cuvieri followed. Finally, the Mona Island marine turtle monitoring program is discussed and compared to other similar programs in Puerto Rico. As these and other similar conservation efforts provide scientifically based management recommendations, we hope to succeed in conserving the diverse herpetofauna that characterizes Puerto Rico.

Assessing the status of tropical dry forest habitats using remote sensing technologies is one of the research priorities for Neotropical forests. We developed a simple method for mapping vegetation and habitats in a tropical dry forest reserve, Mona Island, Puerto Rico, by integrating the Normalized Difference vegetation Index (NDvI) from Landsat, topographic information, and high-resolution Ikonos imagery. The method was practical for identifying vegetation types in areas with a great variety of plant communities and complex relief, and can be adapted to other dry forest habitats of the Caribbean Islands. NDvI was useful for identifying the distribution of forests, woodlands, and shrubland, providing a natural representation of the vegetation patterns on the island. The use of Ikonos imagery allowed increasing the number of land cover classes. As a result, sixteen land-cover types were mapped over the 5 500 ha area, with a kappa coefficient of accuracy equal to 79 %. This map is a central piece for modeling vertebrate species distribution and biodiversity patterns by the Puerto Rico Gap Analysis Project, and it is of great value for assisting research and management actions in the island. Rev. Biol. Trop. 56 (2): 625-639. Epub 2008 June 30.El estudio y evaluación de los bosques tropicales secos mediante herramientas de teledetección es una de las prioridades de investigación en los ambientes neotropicales. Desarrollamos una metodología simple para mapear la vegetación de la isla de Mona, Puerto Rico, mediante el uso del índice de vegetación normalizado (NDVI por sus siglas en inglés) de Landsat, información topográfica, e imágenes auxiliares de alta resolución Ikonos. La metodología fue útil para identificar las clases de vegetación en un área de gran variedad de comunidades vegetales y relieve complejo, y puede ser adaptada a otras regiones de bosque seco de las islas del Caribe. El NDVI permitió identificar la distribución de los bosques cerrados, abiertos, y arbustos, proveyendo una representación natural de los patrones de vegetación en la isla. Las imágenes de Ikonos permitieron incrementar el número de clases detectadas. Como resultado, mapeamos 16 clases de cobertura del terreno en las 5 500 hectáreas de la isla de Mona, con un coeficiente de concordancia kappa de un 79%. La información obtenida en este estudio será utilizada para modelar la distribución de los vertebrados terrestres y patrones de biodiversidad en la isla, como parte del proyecto Gap Análisis de Puerto Rico, y es de gran valor para asistir en las actividades de investigación y manejo en la isla.