Assessing Urban Bat Roost Dynamics in City Zoo: A Case Study

Thesis Abstract

Urban bat roosts in metropolitan zoological settings face multifaceted challenges including microclimate alterations, visitor disturbances, and habitat fragmentation, which collectively influence bat behavior, reproduction, and urban ecosystem services. This study addresses the gap in empirical understanding of how urban zoo environments shape roost selection, occupancy dynamics, and roost-trophic interactions among bat populations, with implications for welfare, conservation, and urban planning. The aim is to assess roost dynamics, habitat use, and health indicators of urban bats within City Zoo, and to evaluate how zoo-associated factors drive occupancy patterns and activity budgets over a 12-month cycle. Specific objectives are to (1) quantify roost occupancy rates and spatial distribution of bat species across zoological enclosures; (2) examine microclimate (temperature, humidity), roost design features, and anthropogenic disturbance as predictors of roost selection using generalized linear mixed models; (3) assess bat body condition and reproductive status as health proxies in relation to roost characteristics; (4) analyze foraging activity and prey availability using acoustic monitoring and light-level data to determine shifts in foraging niches; and (5) develop evidence-based recommendations for roost management and enclosure design that balance animal welfare with educational and conservation objectives. The methodology employs a mixed-methods design integrating quantitative ecological surveys with qualitative stakeholder interviews. The population comprises bat species regularly observed in City Zoo, including Pipistrellus pipistrellus, Nyctalus noctula, and Myotis spp., with an intended sample of 120 roost sites recorded over four seasons. Data collection instruments include ultrasonic bat detectors (-ultra, full-spectrum), infrared temperature and humidity loggers installed in 60 focal roosts, standardized roost-use checklists, midwifery-like health assessments of a non-invasive nature (manual palpation avoided; body condition scored via photographic morphometrics and wing-ding measurements), and structured interviews with zookeeper staff and veterinarians. Validity and reliability are ensured through calibration of acoustic equipment, inter-observer reliability exercises for roost surveys (Cohen’s kappa >0.8), and piloting of health assessment protocols. Data analysis will utilize generalized linear mixed models (GLMMs) to identify predictors of roost occupancy and activity budgets, with species and roost site as random effects. Temporal patterns will be explored via time-series decomposition and seasonal ANOVA to detect month-to-month variation. Acoustic data will be processed for call-structure classification and relative abundance indices using specialized software (Kaleidoscope Pro, 2FA classifiers). Health indicators will be analyzed through linear mixed-effects models linking body condition scores to roost microclimate and disturbance indices. A conceptual framework grounded in the Ecological Niche Theory and the Biophilic Design model will guide interpretation, complemented by the Public Health Theory to address zoonotic risk mitigation. Expected findings include higher occupancy in roosts with stable microclimates, lower disturbance scores, and structural complexity that mimics natural roosts; foraging activity is anticipated to peak in dusk hours with prey abundance correlating to enclosure proximity to insect-rich habitats; bats exhibiting stable or improving body condition in optimally designed roosts; and evidence of species-specific responses to anthropogenic noise and light. These results are anticipated to contribute to knowledge on how urban zoos can function as heterogeneous habitats that support bat biodiversity while enhancing visitor education and welfare standards. The study will advance theoretical understanding of urban roost dynamics within managed ecosystems and provide practical recommendations, such as incorporating temperature-controlled roost cavities, reducing artificial lighting near roosts, embedding bat-friendly habitat features into enclosure design, and adopting disturbance-minimization protocols during peak bat activity periods. A central conclusion is that purposeful roost architectural design and targeted microclimate management within City Zoo can bolster bat occupancy and health without compromising animal welfare or public engagement. Recommendations include implementing modular roost systems with adjustable humidity and temperature settings, scheduling maintenance to avoid peak activity windows, and integrating bat-monitoring dashboards for ongoing welfare assessment and educational outreach.