A SPATIAL AND TEMPORAL ANALYSIS OF BAT ACTIVITY AND DIVERSITY WITHIN A HEAVILY FRAGMENTED LANDSCAPE PDF Download

Author: Christian Edward Nordal
Publisher:
ISBN:
Category : Bats
Languages : en
Pages : 122

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Book Description
The Oak Openings Region of Northwest Ohio of Northwest Ohio is an incredibly biodiverse area that is home to many rare and endangered plant and animal species. Furthering our knowledge and understanding on the resident bat species within the region is critical as populations of many species have declined from White-nose Syndrome, habitat loss and fragmentation, and wind energy barotrauma. To further bat-specific research in the region, my thesis research focused on: 1) identifying the relationships between bat activity and diversity and fragmentation features; 2) monitoring trends in activity and richness between forested and savanna sites over time; and 3) developing refined spatially explicit habitat models of bat occupancy using data collected from protected and unprotected habitat and comparing them to models created from strictly protected habitat. Ecological knowledge on bats and their response to features commonly associated with habitat fragmentation is lacking, so I acoustically surveyed thirty roads with Anabat SDII monitors within and outside of protected areas. I utilized logistic regression analysis to examine the relationship between presence/absence and activity of each species with each feature (e.g. proportion of road with overstory) to select candidate variables for multivariate models. I then created candidate multivariate models for each species and selected final models based on parsimony, AIC values, and adjusted R square values. Bats had a differential response to features between species, and park managers must consider the management of roads on a species- specific viewpoint if they plan to focus conservation efforts on bats. For the second part of my research, I surveyed bat relative activity within forest and savanna sites and compared the data to previous monitoring efforts. Within the single year I monitored, savanna sites appeared to host a greater activity for many species and a greater species richness. Between years, savanna sites remained predominantly stable in species composition and activity, but forested sites had declines in activity among certain species and declines in species richness. Results demonstrate a need for further investigation of forest habitat and additional comparisons between savannas and other open habitat to determine their role for bats in the region. For the third part, I developed Maxent species distribution models for seven species of bats that occur in the region and compared them to existing models. I tested previously developed occupancy models' predictive power using new data. Once data were demonstrated to be comparable through model performance, I created new models from a combination of previous (prior to White-nose) and new data (post White-nose). I then tested previous and new models with an independent dataset and compared their performances and areas of predicted presence for each species. The addition of new data refined previous models and offered a species-specific view on the importance of prominent landscape characteristics for probability of presence. The results of this thesis research contribute to our knowledge of bats within the Oak Openings Region and provide tools for adaptive management in fragmented landscapes.