Assessing the Impact of Urbanization on Bat Diversity in Riverside City Parks

Thesis Abstract

Urbanization has profoundly transformed natural habitats worldwide, leading to significant concerns regarding its impacts on local biodiversity, particularly arboreal and insectivorous species such as bats that play vital roles in ecosystem functioning. This study investigates the influence of urban development on bat diversity within Riverside City Parks, aiming to provide empirical evidence necessary for sustainable urban planning and biodiversity conservation. The specific objectives are to (1) assess the species richness and composition of bats across parks with varying degrees of urbanization, (2) examine habitat and environmental variables influencing bat diversity, and (3) evaluate the implications of urban habitat fragmentation on bat population dynamics. The research adopts a comparative cross-sectional design, integrating field surveys and geospatial analysis. The population encompasses bat species within five major parks in Riverside City, selected based on size, vegetation cover, and proximity to urban infrastructure. A sample size of 150 acoustic monitoring sessions per park over a 12-month period ensures seasonal variation is captured, totaling 750 sampling sessions. Data collection involves ultrasonic bat detectors (e.g., Anabat SD2) for bioacoustic sampling to identify species-specific echolocation calls, complemented by habitat assessments using standardized botanical and insect surveys, along with remote sensing data to quantify habitat fragmentation and land-use patterns. Instrument validity is ensured through calibration of acoustic devices and pilot testing of habitat assessment protocols. Reliability is enhanced via repeated sampling across different seasons and times of day. Analytical techniques include species richness indices (Shannon-Wiener, Simpson’s Diversity), multivariate analysis through Non-metric Multidimensional Scaling (NMDS) for community composition, and generalized linear models (GLMs) to examine the relationships between bat diversity metrics and environmental variables. Spatial analysis using Geographic Information Systems (GIS) contextualizes habitat changes, while regression analysis determines key factors influencing bat distribution. Expected findings anticipate that parks with higher green cover and connectivity support greater bat species richness and diversity, whereas increased habitat fragmentation correlates negatively with bat abundance and species presence. The study hypothesizes that urbanization-induced habitat loss reduces suitable roosting and foraging sites, leading to simplified bat communities dominated by generalist species, in line with the habitat filtering theory. It further posits that certain environmental features, such as proximity to water bodies and native vegetation corridors, serve as critical determinants of bat diversity in urban parks. This research contributes to knowledge by providing localized, evidence-based insights into how urbanization shapes bat communities in tropical city environments, filling a literature gap regarding bat conservation within urban landscapes. It also offers a framework for incorporating biodiversity considerations into urban planning practices. The main conclusion emphasizes the necessity of integrating habitat connectivity and native vegetation preservation within urban development policies to mitigate biodiversity loss. Recommendations include establishing ecological corridors, enhancing native plantings, and implementing habitat management strategies tailored to conserve diverse bat assemblages. The study further advocates for longitudinal monitoring to evaluate the effectiveness of urban conservation efforts and calls for policy integration at municipal levels to foster resilient urban ecosystems that support bat diversity alongside human development objectives.