Descripción de los nidos del Cocodrilo de pantano Crocodylus moreletii en un paisaje urbanizado en el sureste de México

Laguna de las Ilusiones is an isolated urban lake in the city of Villahermosa, Tabasco in México that retains a population of Morelet´s crocodile (Crocodylus moreletii ). During the years 2007 and 2008 we studied 22 natural nests of this species. Most of the nests (53%) were built with vegetal material (leaf-litter, stems and thin branches). Also, we recorded human waste as part of the materialsfor nest construction. Mean clutch size was 30.4 ± 10. 8 eggs by nest (nests n = 19, eggs n = 578). Mean egg volume is significantly different among nests, an indication of size differences between the nesting females. Physical characteristics of the nests in 2007-2008 were compared with nests found at the same area during 1991-1994. We found that nest diameter, shore distance and clutch size were significantly higher in 2007-2008. Hatching in Laguna de las Ilusiones was low during 2007-2008 (33.9% ± 31.21) compared with other crocodilians. All new born crocodiles in 2007 and 2008 were males. We discuss how the city may affect the nesting of Morelet´s crocodiles, influencing different aspects such as, theuse of new materials for nest construction, increasing the size of the basal area of the nests, or promoting the search for a nesting site away from the shore. We recommend a management of the crocodiles with female reintroduction and artificial incubation in the Laguna de las Ilusiones to facilitate conservation of this population.La Laguna de las Ilusiones es un lago urbano aislado en la ciudad de Villahermosa, Tabasco que mantiene una población de cocodrilo de pantano (Crocodylus moreletii). Durante los años 2007 y 2008 se estudiaron 22 nidos silvestres de esta especie. En la mayoría de los nidos (53%) además de estar construidos con material vegetal (hojas, tallos y ramas delgadas) se registran productos de desechohumano como parte de los materiales para construcción de los nidos, el resto de los nidos está construido como lo descrito en otros trabajos. El tamaño promedio de la nidada es de 30.4 ± 10.8 huevos por nido (nidos n = 19, huevos n = 578). El tamaño y volumen promedio de los huevos es significativamente diferente entre nidos, lo que indica que existen diferencias en los tamaños de las hembras nidificantes. Las características físicas de los nidos en 2007-2008 fueron comparadas con las de otros nidos encontrados en la misma área de estudio en el periodo 1991-1994, encontrando que el diámetro de los nidos, la distancia a la orilla y el tamaño de la nidada son significativamente mayores en 2007-2008. El porcentajede eclosión en 2007-2008 en la Laguna de las Ilusiones es bajo (33.9 ± 31.21) comparado con otras especies de cocodrilianos. El 100% de los neonatos en 2007 y 2008 fueron machos. El efecto de la ciudad posiblemente puede afectar la ecología de la anidación en el cocodrilo de pantano, influyendo en nuevos materiales para la construcción de los nidos, aumentando el tamaño del área basal de los nidos y promoviendo la búsqueda de lugares más alejados de la orilla para la anidación. Debido al fuerte sesgo que existe hacia los machos en los nacimientos, se recomienda un manejo de la de la población de cocodrilos que incluya la reintroducción de hembras e incubación artificial en la Laguna de las Ilusiones que coadyuve a la conservación de esta población en esa área

Primer registro de la comadreja (Mustela frenata) en el estado de Campeche, México

In this paper, we report three different records of the long tail weasel (Mustela frenata) using camera traps in the western portion of Campeche; thus confirming the presence of the species in this Mexican state

Activity patterns of tayra (Eira barbara) across their distribution

Species' activity patterns are driven by the need to meet basic requirements of food, social interactions, movement, and rest, but often are influenced by a variety of biotic and abiotic factors. We used camera-trap data to describe and compare the activity patterns of the relatively poorly studied tayra (Eira barbara) across 10 populations distributed from the south of Mexico to the north of Argentina, and attempted to identify biotic or abiotic factors that may be associated with variation in level of diurnality. In a subset of sites we also aimed to document potential seasonal variation in activity. We used a kernel density estimator based on the time of independent photographic events to calculate the proportion of diurnal, crepuscular, and nocturnal activity of each population. Tayras were mostly active during diurnal periods (79.31%, 759 records), with a lower proportion of crepuscular activity (18.07%, 173 records) yet we documented some variation in patterns across the 10 study areas (activity overlap coefficient varied from Δ4 = 0.64 to Δ1 = 0.95). In northern localities, activity peaked twice during the day (bimodal) with most activity ocurring in the morning, whereas closer to the geographical equator, activity was constant (unimodal) throughout the day, peaking at midday: activity either was unimodal or bimodal in southern localities. Despite investigating multiple potential abiotic and biotic predictors, only latitude was associated with variation in the proportion of diurnal activity by tayras across its range, with increased diurnal activity closer to the equator. Seasonal comparisons in activity showed a tendency to reduce diurnality in dry versus rainy seasons, but the pattern was not consistently significant. This is the most comprehensive description of tayra activity patterns to date, and lends novel insight into the potential flexibility of the species to adapt to local conditions.Fil: Villafañe Trujillo, Álvaro José. Universidad Autonoma de Queretaro.; MéxicoFil: Kolowski, Joseph M.. Instituto de Pesquisas Ecológicas; BrasilFil: Cove, Michael V.. University of Belize; BeliceFil: Medici, Emilia Patricia. Instituto de Pesquisas Ecológicas; BrasilFil: Harmsen, Bart J.. University of Belize; BeliceFil: Foster, Rebbeca J.. University of Belize; BeliceFil: Hidalgo Mihart, Mircea G.. Universidad Juárez Autónoma de Tabasco,; MéxicoFil: Espinosa, Santiago. Universidad Autónoma de San Luis Potosí; MéxicoFil: Ríos Alvear, Gorky. Universidad de Porto; PortugalFil: Reyes Puig, Carolina. Universidad de Porto; PortugalFil: Reyes Puig, Juan Pablo. Universidad de Porto; PortugalFil: Da Silva, Marina Xavier. Universidad Central del Ecuador; EcuadorFil: Paviolo, Agustin Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Universidad Nacional de Misiones. Instituto de Biología Subtropical; ArgentinaFil: Cruz, Paula Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Universidad Nacional de Misiones. Instituto de Biología Subtropical; ArgentinaFil: López González, Carlos Alberto. Universidad Autonoma de Queretaro.; Méxic

Registro de pecarí de labios blancos (Tayassu pecari) en la región de la laguna de Términos, Campeche, México White lipped pecaries (Tayassu pecari) recorded in the area of Términos Lagoon Campeche, México

Se registró fotográficamente al menos un grupo de pecaries de labios blancos (Tayassu pecari) en la Selva La Montaña, al suroeste del área de Protección de Flora y Fauna Silvestre Laguna de Términos, Campeche, México. El registro se realizó utilizando trampas cámara. La presencia de esta especie muestra la importancia que tiene la región Selva La Montaña para la conservación de la biodiversidad, especialmente para las especies protegidas.We report at least one group of white lipped peccaries (Tayassu pecari) in Selva La Montaña located in the southwestern portion of the Términos Lagoon Flora and Fauna Protection Area, Campeche, Mexico. The record was obtained using camera traps. The presence of this species in the area shows the importance of the region for biodiversity conservation, particularly for protected species

Conservation implications for jaguars and other neotropical mammals using highway underpasses.

The Nuevo Xcan-Playa del Carmen highway in Quintana Roo, bisects the vegetation corridor connecting two Jaguar Conservation Units (JCUs): Yum Balaam (north) and Sian Ka´an (south). The project´s main goal was to describe differential use of available crossing structures (wildlife underpasses and culverts) by mammals present along this highway. We set 28 camera traps along the 54km stretch of the highway covering wildlife underpasses (10), and culverts such as box culverts (9) and pipes (9) from September 2016 until March 2017. A total of 24 jaguar crossings have been recorded exclusively using wildlife underpasses, including four males and two females. At least 18 other mammal species including five of the target priority species (protected by Mexican law) were documented, all of which were native except for two invasive species. In terms of species using the crossing structures, we identified 13 species using wildlife underpasses, nine using concrete box culverts and 10 using concrete pipes. Wildlife underpasses show higher diversity values (Shannon´s exponential index = 5.8 and Inverse Simpson´s index = 4.66) compared to culverts because they allow bigger species to cross. We recommend more highways along the jaguar´s distribution should develop mitigation measures to allow for wildlife connectivity. Wildlife underpasses, along with retrofitted culverts, could help secure not only the permanence of this species by facilitating the functional connectivity between populations but have positive impacts on other neotropical mammalian fauna as well

COMPARACIÓN DE LA RIQUEZA DE ESPECIES DEL ORDEN CHIRÓPTERA EN MÉXICO Y COLOMBIA

Se realizó una revisión bibliográfica para comparar la riqueza de especies de murciélagos de México y Colombia con respecto a la altitud, encontrando que la mayor riqueza para este orden de mamíferos ocurre en un gradiente de elevación de 0 a 3,500 msnm para México y de 0 a 4,000 msnm para Colombia; siendo la riqueza de especies inversamente proporcional a la altitud