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Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-10T18:55:49Z No. of bitstreams: 1 2012 - Gustavo Pena Freitas.pdf: 3480263 bytes, checksum: e0c63bdd4112e143bb273fe93d21ce6e (MD5) / Made available in DSpace on 2017-05-10T18:55:49Z (GMT). No. of bitstreams: 1 2012 - Gustavo Pena Freitas.pdf: 3480263 bytes, checksum: e0c63bdd4112e143bb273fe93d21ce6e (MD5) Previous issue date: 2012-02-29 / CAPES / This work aimed to study a population of Molossus molossus (Pallas , 1766) on Praia do Gato, llha de Itacuru??, Rio de Janeiro, analyzing aspects such as variation of colony size, use of roost, reproduction and activity. For this work 18 sampling nights were performed at intervals of 40 days between each month, between August 2009 and August 2011. Mist nets were opened near the access of two roosts, one in a house roof and another in a hollow of a tree. During the 25 sampling months, 689 captures and recaptures were done, and 309 individuals were marked. The number of captured and recaptured animals varied during the sample period, being inversely proportional to the duration of the night, with the months of November/2009 (88 individuals) and December/2009 (78 individuals) recording the highest number of catches. A decreasing number of individuals were observed in the second year of sampling as a possible consequence of the capture stress and/or the learning of the mist nets position by the bats. It was observed a greater number of transient individuals and a higher number of females throughout the study. In the roof was observed a greater number of young bats, possibly due to the higher temperature recorded. The bats performed exchanges between these two roosts throughout the year, being recorded 36 individuals performing exchanges, and the occurrence of 51 of such events. In relation to the reproduction, females had a monoestrous reproductive pattern, comprised between the months of November and January, with the males not showing a definite pattern. In relation to the activity period, the species showed a predominantly crepuscular pattern, with the females leaving the shelters earlier than the males, possibly due to increased energy demand. The animals spent an average of 36 minutes outside the roost, ingesting an average of 0.8 g of food, showing no difference throughout the year. / Este trabalho teve como objetivo geral realizar um estudo sobre uma popula??o de Molossus molossus (Pallas, 1766) na Praia do Gato na Ilha de Itacuru??, Rio de Janeiro, analisando aspectos como varia??o do tamanho da popula??o, uso dos abrigos, reprodu??o e atividade. Para o desenvolvimento deste trabalho foram realizadas 18 noites de amostragens com intervalos de aproximadamente 40 dias entre cada uma delas entre os meses de agosto de 2009 e agosto de 2011. Redes de neblina foram armadas pr?ximas as sa?das de dois ref?gios encontrados na praia, um em forro de uma resid?ncia e outro no oco de uma ?rvore. Durante os 25 meses de acompanhamento da col?nia, foram realizadas 689 capturas e recapturas, sendo marcados 309 indiv?duos. O n?mero de animais capturados e recapturados variou durante o per?odo de amostragem, sendo inversamente proporcional ? dura??o da noite, com os meses de novembro/2009 (88 indiv?duos) e dezembro/2009 (78 indiv?duos) registrando os maiores n?meros de capturas. Foi observado um decr?scimo no n?mero de indiv?duos no segundo ano de amostragem, como poss?vel consequ?ncia do estresse de captura e/ou do aprendizado pelos morcegos da posi??o das redes. Foram observados tamb?m um maior n?mero de indiv?duos transientes e um maior n?mero de f?meas, durante todo o trabalho. No forro da resid?ncia foi observado um maior n?mero de jovens, possivelmente em virtude da maior temperatura registrada. Os indiv?duos realizaram trocas entre esses dois abrigos durante todo o ano, sendo registrados 36 indiv?duos realizando trocas e a ocorr?ncia de 51 eventos desse tipo. Com rela??o ? reprodu??o, as f?meas apresentaram um padr?o reprodutivo mono?strico compreendido entre os meses de novembro e janeiro, com os machos n?o apresentando um padr?o sazonal definido. Com rela??o ao per?odo de atividade, a esp?cie apresentou um padr?o predominantemente crepuscular, com as f?meas saindo primeiro que os machos dos abrigos, possivelmente pela maior demanda energ?tica. Os animais gastaram em m?dia 36 minutos fora do abrigo, ingerindo em m?dia 0,8 gramas de alimento, n?o ocorrendo diferen?a ao longo do ano.

White-nose syndrome (WNS), caused by the introduced fungal pathogen, Pseudogymnoascus destructans, has caused precipitous declines in bat populations including the now endangered northern long-eared bat (Myotis septentrionalis; NLEB). Remnant populations of NLEB have been found outside their traditional range in areas of the urbanized Piedmont and also the Coastal Plain of the mid-Atlantic region of the United States, where little is known about their summertime day-roost habitat needs. More broadly for the species, little research has examined the day-roost habitat use of both male and females. This information is vital to inform management and policy for the conservation of this endangered species. In this dissertation, I captured NLEB at three properties in eastern Virginia and Washington D.C. Captures at Marine Corps Base Quantico (MCBQ) and Prince William Forest Park (PRWI) in Virginia were male-biased and Rock Creek Park (ROCR) captures in D.C. were female-biased. I found that overall NLEB are associated with mature, deciduous forest. Males used red maples (Acer rubrum) in later decay stages and lower crown classes at MCBQ/PRWI. Females used taller oaks (Quercus) at ROCR. Differences between the two study areas may be an artifact of MCBQ/PRWI being an early mature forest whereas much of ROCR is approaching late mature to old-growth gap-phase conditions. Building off the fact that many WNS affected bat species are now substantially more difficult to detect on the landscape, I explored novel methods to help increase detection of bats during acoustic surveys. This included developing and testing an experimental ultraviolet (UV) light lure that attracted insects and thereby attracted bats. The lure increased overall bat feeding buzz calls and had a species-specific response, primarily attracting eastern red bats (Lasiurus borealis). The lure elicited an interesting negative response from NLEB within the illuminated area, but an increase above control conditions beyond the illuminated area. Overall, the UV lure shows promise for increasing detection of bats and warrants further research, however caution should be exercised as some bats showed a negative response. I also investigated the effects of environmental clutter on the reception of ultrasonic bat echolocation signals to help researchers better understand how different clutter types and configurations affect and potentially bias acoustic survey results. This is especially important when surveying for clutter-adapted bats, such as NLEB which are traditionally biased against in acoustic surveys due to their habitat associations and low detection probability. I found that the recording angle of the bat in relation to the microphone overshadowed most other effects. On-axis recording created the best quality recording and the signal rapidly degraded as the angle increased. Therefore, placement of microphones to where bats are expected to be flying is critical. Many small clutter objects, analogous to a young forest with a high stocking rate substantially degraded echolocation signals. Fewer, large objects, analogous to a mature forest with large trees and little understory actually generated echoes that were identifiable to species that would be beneficial to improving detection probability and occupancy estimates, but might generate bias by overcalculating activity estimates. / Doctor of Philosophy / A disease called white-nose syndrome (WNS), caused by the fungal pathogen, Pseudogymnoascus destructans, was introduced into the U.S. around 2006 and has decimated bat populations across much of the U.S. and Canada. Bats are responsible for providing important pest insect control services to the agriculture and forestry industries as well as helping to control disease carrying insects. Once particular species, the northern long-eared bat (Myotis septentrionalis; NLEB) has seen some of the heaviest declines. Once a common bat in forests across the eastern and mid-western portions of North America, the NLEB is now considered an endangered species. Recently, populations of this bat have been found in areas where they were previously not known to exist and they represent potentially important remnant populations with high conservation value. In order to protect these NLEB, scientists must understand their forest habitat needs for roosting during the day and rearing young. Most past studies have focused on female NLEB, so information on male roost use is also needed. I captured NLEB at Marine Corps Base Quantico (MCBQ) and Prince William Forest Park (PRWI) in Virginia as well as at Rock Creek Park (ROCR) in Washington, D.C. and tracked NLEB to their day-roosts to characterize their habitat needs at multiple scales ranging from the day-roost itself, the surrounding forest area, and the greater landscape around the bat roosting areas. I found that NLEB prefer to roost in older deciduous hardwood forests. Male NLEB used red maples (Acer rubrum) that were shorter and more decayed than surrounding trees at MCBQ/PRWI. Females used taller oak trees (Quercus) at ROCR. Differences observed in the analysis between the two study areas may be an artifact of MCBQ/PRWI being a younger forest whereas much of ROCR is approaching conditions of a very old forest. Building off the fact that many WNS affected bat species are now substantially more difficult to find out on the landscape, I explored new research methods to help increase detection of bats during acoustic surveys. Scientists often use acoustic recording devices to record ultrasonic (above human hearing) echolocation calls that bats use for navigation and hunting at night. Those calls can be identified as specific types of bats for use in environmental studies using automated computer programs. The problem however, is that bats must fly close to the microphone in order to record a clear sound file that can be identified by the software. I built and tested a device that uses ultraviolet (UV) "blacklights" to attract insects that bats eat and thereby attract bats to an array of recording devices. The lure device worked, but for individual species of bats rather than all bats. Of particular interest is that NLEB were repelled within the area illuminated by the UV light lure, but increased outside the illuminated area. Overall, a UV light lure shows promise for increasing detection of bats, but caution is recommended because some bats seemed to avoid the light. I also investigated how clutter around these recording devices, such as trees and branches, affects the quality of recorded sound files under controlled conditions. I found that the angle of the recording device microphone to the sound source (a bat) mattered the most. Many smaller objects between a bat and the microphone, such as many small trees in a young forest, resulted in the worse recordings. Fewer large objects, such as large, old trees, resulted in echoes of the bat calls being recorded and actually helped the software identify the calls to a specific type of bat. However, this also warrants caution, as those echoes could introduce bias into counts of nightly bat activity.

Fifty-nine female and six male little brown myotis (Myotis lucifugus) were radio-tagged during the summers of 2012, 2013, 2014, and 2015 in Yellowstone National Park. The grand models for daily maximum skin temperature (F98,154 = 1.55, P = 0.007), daily minimum skin temperature (F98,154 = 1.33, P = 0.05), and daily variation in skin temperature (F98,154 = 1.56, P = 0.006) were significant across roost type and reproductive condition class for adult females. Roosts were classified into Types A (warmest roosts), B (roosts with largest daily temperature variance), and C (stable and cool roosts) depending on differences in mean maximum, minimum, and variance in temperatures per day (P < 0.001). A total of 347 torpor bouts were recorded from 38 females across the 2012 to 2015 summer seasons. Bats across different reproductive classes and roost types used torpor at different hours of the day. My research suggests that adult female little brown myotis at high elevations in the Park extensively use and rely on building structures for roosting sites during the reproductive season, whereas males used primarily natural roosts.