North American Symposium on Bat Research San Jose, Costa Rica August 11-15, 2013

North American Symposium on Bat Research San Jose, Costa Rica August 11-15, 2013

AAbbssttrraaccttss Abstracts 16th International Bat Research Conference 43rd North American Symposium on Bat Research San Jose, Costa Rica August 11-15, 2013 Abstracts are arranged in alphabetical order by first author. Titles highlighted in green are oral presentations; those highlighted in orange are posters. The presenting author is the first author unless indicated by an asterisk. Value in Variation? Stationary Acoustic Transects to Account for Spatial Variation in Bat Activity Amanda Adams Western University, Canada The ability to identify and capture different sources of variation at a particular location can impact conclusions drawn from the data. It is important to account for variation to maximize the chances of obtaining unbiased measures of bat activity. When and how to sample is a question that is typically decided by time availability, manpower, and equipment limitations. My objective was to quantify small scale spatio-temporal variation in bat activity and demonstrate how it can affect acoustic sampling design. I used a stationary transect of bat detectors to i) assess variation in patterns of activity at each detector, ii) test whether spatial or temporal factors were more important for explaining variation in activity, iii) explore what sampling effort in space and time is required for species-specific activity levels. The picture of activity differs significantly within a site depending on detector placement so it is important to use multiple detectors simultaneously to collect accurate estimates of activity. I found that within site factors are very important to understanding variation in bat activity, being as or more important than differences among sites. The high degree of variation within sites can affect sampling design, including necessary effort and number of detectors recording simultaneously. Detector placement within a site will dramatically impact the depictions of activity, impacting estimates of levels and patterns of activity. An a priori understanding of the survey effort necessary will help ensure statistically powerful sampling designs, clearer data interpretation, and likely more successful management and conservation actions. Will Increased Drought Alter Population Numbers and Community Structure of Bats in the Southern Rocky Mountains? Rick Adams University of Northern Colorado, USA The effects of climate disruption are underway in the Southern Rocky Mountains. Highest elevations are warming fastest thereby reducing winter snowpack and spring runoff. At lower elevations, warmer temperatures and reduced summer precipitation causes decreases in stream discharge rates, and water availability, once snowpack is exhausted. We show the results of reduced water availability on Rocky Mountain bat reproduction by both direct measurements of numbers of drinking visits by lactation versus nonlactating M. thysanodes (Nlac = 236, Nnonrepro = 18; P = 0.0001) and by linking reproductive patterns of myotis species gathered under variable annual weather conditions across 13 years. Decreases in precipitation and stream discharge rates correlated strongly with decreased lactation (R = 0.85 and 0.79. respectively). We also show that intense activity at drinking sources immediately after evening emergence involves both cooperation and competition among species that appears to structure larger regional population numbers and coexistence. Shannon Diversity Indexes (H') for all bats captured (N = 2,299) was 1.65, which was consistent with four water sites where nine species of bats swarmed to drink: Ingersol Quarry (N = 147) 1.50; Geer Canyon (N = 522) 1.61; Shadow Canyon (N = 475) 1.51 and Bear Creek (N = 458) 1.61. Thus, the overall regional assemblage structure strongly correlated with species proportionality at individual water sources (R = 0.98) despite variability in which species dominated in numbers at each site. Thus, the loss of water sources in proximity to roost sites due to climate change may result in alterations in proportional population numbers at a larger regional scale. How Flower Morphology Influences Flower-visiting Behavior of Bats and the Reproductive Success of Mucuna urens (Leguminosae) Kayna Agostini and Marlies Sazima Universidade Federal de São Carlos; Universidade Estadual de Campinas, Brazil The genus Mucuna shows explosive flower opening and an impressive radiation involving different pollinators has taken place. Studies discovered that floral parts function as acoustic guides that help bats locate the flowers using echolocation. The aim of this study was to verify how flower morphology influences flower-visiting behavior of bats and the reproductive success of Mucuna urens. Pollination biology of Mucuna urens was studied in the southeastern Brazilian rainforest. Each inflorescence bears 36-54 greenish, fetid and medium size flag-flowers, but only 1-3 nocturnal flowers are in anthesis simultaneously with abundant nectar. These features are associated with bat pollination. The reproductive organs are enclosed in the keel, being released after explosive flower opening, 16th International Bat Research Conference & 43rd North American Symposium on Bat Research launching pollen against the pollinator. The principal pollinator is Glossophaga soricina, which have adequate behavior to trigger the explosive mechanism of this flower. During the first visit, the bat lands on the flower and triggers the explosive opening mechanism. The staminal tube of the flower then moves towards the standard and does not return to the original form. This changes the floral morphology, possibly affecting the acoustic guide. In subsequent visits to the same flower, bats hovered rather than landing, drinking nectar but failing to contact the reproductive organs. Thus, Mucuna flowers have just one chance to be pollinated. The changes in flower morphology modify flower-visiting behavior of bats, influencing the reproductive success of this Mucuna species. Spectrum Echolocation Calls using HMMs, Fisher Scores, Unsupervised Clustering and Balanced Winnow Pairwise Classifiers Ian Agranat Wildlife Acoustics, Inc., USA A new classification technique for the identification of bats to species from their echolocation calls is presented. Three different datasets are compiled and split in half for training and testing classifiers. Combined, the data include 9,014 files (bat passes) with 226,432 candidate calls (pulses or extraneous noise) representing 22 different species of bats found in North America and the United Kingdom. Some files are of high quality consisting of hand-selected search phase calls of tagged free flying bats while others are from a variety of field conditions including both active (attended) and passive (unattended) recordings made with a variety of zero crossing and full spectrum recording equipment from multiple vendors. Average correct classification rates for the three datasets on test data are 100.0%, 97.9%, and 88.8% respectively with an average of 92.5%, 72.2%, and 39.9% of all files identified to species. Most importantly, classifiers in the third dataset for two species of U.S. endangered bats, Myotis sodalis (MYSO) and Myotis grisescens (MYGR) have a correct classification rate of 100% and 98.6% respectively and identify 67.4% and 93.8% of all files to species suggesting that the classifiers are well suited to the accurate detection of these endangered bats. Anoura geoffroyi as a Pollinator of the Epiphytic Bromeliads Tillandsia heterophylla and T. macropetala in Central Veracruz, MeXico Pedro Adrián Aguilar-Rodríguez, M. MacSwiney González, Thorsten Krömer, and José Guadalupe García-Franco Universidad Veracruzana, México Tillandsia heterophylla and T. macropetala are two epiphytic bromelias of the severely threatened tropical montane cloud forest ecosystem in central Veracruz, Mexico. Both species have floral characteristics that are typically associated with nocturnal pollinators, particularly bats; however, their anthesis begins at dusk and lasts until the following day, which also offers the possibility of daylight visitors. Since the majority of the period the flowers remain open occurs during the night, the most efficient pollinators would be the nocturnal visitors. In order to determine if this is the case, observations and recordings were made of both diurnal and nocturnal visits, along with mist net trapping of the visitors. The nectar production pattern was determined, as well as the duration of stigma receptivity and the presentation of pollen. The bat Anoura geoffroyi was the only observed pollinator of T. macropetala, while in T. heterophylla, this bat was the most common pollinator, followed by hummingbirds. T. heterophylla is autocompatible and presents no differences in the number of seeds per fruit produced by diurnal or nocturnal animal visits. Conversely, T. macropetala, also autocompatible, only produces fruit following visits by nocturnal animals. Extending anthesis into the daytime has given T. heterophylla access to new pollinators, while for T. macropetala, diurnal visitors simply steal nectar while providing no reciprocal benefit to the plant. The Latin American Bat Conservation Network (RELCOM) Luis Aguirre Universidad Mayor de San Simón, Bolivia With over 360 species of bats living in a variety of ecosystems in Latin America and the Caribbean, the region constitutes the most bat-rich area in the world. Landscapes range from coastal areas in the Caribbean to highlands in the Andes. Within each of these ecosystems, bats fulfill crucial ecological roles. In

View Full Text

Details

  • File Type
    pdf
  • Upload Time
    -
  • Content Languages
    English
  • Upload User
    Anonymous/Not logged-in
  • File Pages
    180 Page
  • File Size
    -

Download

Channel Download Status
Express Download Enable

Copyright

We respect the copyrights and intellectual property rights of all users. All uploaded documents are either original works of the uploader or authorized works of the rightful owners.

  • Not to be reproduced or distributed without explicit permission.
  • Not used for commercial purposes outside of approved use cases.
  • Not used to infringe on the rights of the original creators.
  • If you believe any content infringes your copyright, please contact us immediately.

Support

For help with questions, suggestions, or problems, please contact us