Author: Cheyenne Gerdes Publisher: ISBN: Category : Bats Languages : en Pages : 96
Book Description
Migration is an important and understudied aspect of the life histories of many species, particularly bats. Migration impacts conservation efforts, including efforts to manage the impacts of wildlife disease. The federally endangered gray bat (Myotis grisescens) is a migratory species with documented infections by Pseudogymnoascus destructans, the fungus that causes White-nose Syndrome (WNS). To better understand migration as it might relate to WNS, I quantified the timing and location of gray bat movements in Missouri using acoustic detectors and bat banding. I recorded calls at 4 maternity sites from January to May 2015, and used the R package PVAClone to generate estimates of r and K as measures of arrival rate and an index of population size at the maternity sites respectively. These values were plotted against each cave’s distance from a major hibernaculum to examine whether there was an effect on the arrival of gray bats at a site. Values of r varied between 0.3 and 0.9, and values of K varied between 981 and 3020 among the maternity roosts: estimates were consistent whether considering observation error or not. While bats arrived at the closest maternity colony quicker and in greater numbers, the remaining rates and indices were equivocal with distance. Over 1,000 gray bats were banded and 18 were relocated, revealing previously undocumented connections between gray bat caves across the region. The acoustic methodology used in this thesis could be useful for management officials wanting to monitor the timing of bat migration and site activity, both of which could be affected by WNS. The cave network used by gray bats in Missouri could yield insight into how WNS spreads across cave networks.
Author: Joshua David Parris Publisher: ISBN: Category : Bats Languages : en Pages : 138
Book Description
The arrival of white-nose syndrome (WNS) has stimulated interest in winter bat activity. Data from a bat activity study in southern Missouri indicated winter gray bat (Myotis grisescens) activity above expected levels. Study objectives were to assess gray bat winter activity including investigating winter feeding, the need for water, whether winter activity occurs at caves and foraging areas, whether gray bats are more active relative to other species, and the effect of climate variables. Acoustic monitoring occurred over three winters at areas in Laclede, Shannon, and Washington counties Missouri, and captures occurred during the 2012-13 winter at Coffin Cave in Laclede County and Bat Cave in Shannon County. I collected temperature, humidity, and barometric pressure data at Coffin Cave and Bat Cave during 2012-13. Gray bats were captured on 24 of 26 attempts, at temperatures as low as -1.7oC. Of 350 bats captured, three provided a feeding fecal sample during mid-winter. Urinating was recorded in >50% of gray bats. Those at Coffin Cave, with available water, urinated earlier than at Bat Cave, with no available water. Acoustic data indicated that gray bats were active all winter at caves and foraging areas and at higher proportions than expected based on cave populations. Activity at Bat Cave correlated with inside humidity and outside temperature, while activity at Coffin Cave did not correlate with climate variables. Activity at Bat Cave was higher than at Coffin Cave. Water needs appear to drive activity.
Author: Larisa Jo Bishop-Boros Publisher: ISBN: Category : Bats Languages : en Pages : 456
Book Description
Understanding the influence of weather on reproductive events is critical for documenting population demographics and developing appropriate conservation and management strategies. Variations in timing of parturition may be due to changes in the ambient weather which affect the available insect prey density and time reproductive bats must spend torpid. Capture data from 6,767 bats representing 12 species from 28 counties and 360 sites, were used to examine the influence of precipitation, temperature, and latitude on reproduction of bats in Missouri. Although both cool springs and heavy spring precipitation delayed the onset of each reproductive condition, temperature had a greater influence on reproductive timing. Contrary to predictions, high spring precipitation increased reproductive rate and increased synchrony in dates of pregnancy. Differences in onset of reproduction between northern and southern Missouri were not significant, although capture of juveniles ended sooner in northern Missouri. There was a difference in peak nightly activity among bats of different reproductive conditions for all species except Indiana bats, which had a later interspecific activity peak. Red bats had a female biased juvenile sex ratio especially early season, northern bats and gray bats were male biased. Five species had adult male biased sex ratios. Lactating female big brown bats have a lower mass in years with cooler springs. The inevitable escalation of climatic extremes may cause Midwestern bat species to experience environmental stressors in different ways. These data provide regional managers with better tools to address seasonal Indiana bat survey guidelines and potentially inform seasonal mitigation of wind energy facilities based on annual weather variation.
Author: Cheyenne Gerdes
Author: 
Author: Richard L. Clawson
Author: Richard K. LaVal
Author: Richard L. Clawson
Author: Wilber J. Gunier
Author: Joshua David Parris
Author: 
Author: Larisa Jo Bishop-Boros
Author: Richard L. Clawson