Scale effects of forest fragmentation on neotropical and temperate bat species

Martinez-Fonseca, Jose Gabriel (2022) Scale effects of forest fragmentation on neotropical and temperate bat species. Doctoral thesis, Northern Arizona University.

Text Martinez-Fonseca_2022_scale_effects_forest_fragmentation_on_neotropica.pdf - Published Version Restricted to Repository staff only Download (2MB) | Request a copy

Abstract

Human-driven disturbances like habitat degradation, fragmentation, and loss are some of the main threats to biodiversity worldwide. The fragmentation of forest habitats can create favorable conditions for edge-dwelling and open forest species which means that the effects of disturbances can be varied, ranging from positive to negative across different taxa and environments. Bats (Order Chiroptera) are the second most diverse order of mammals and play equally diverse and important roles in the function of ecosystems, from tropical to temperate regions globally. Bats, like all wildlife species, select their environment at multiple spatial and temporal scales that correspond with morphological and behavioral traits. However, landscape-species relationships are not well understood, especially in hotspots of bat diversity such as the tropics and subtropics. I conducted three studies focused on exploring, describing, and summarizing bat species interactions with landscape conditions (structure: composition and configuration) across all continents but with emphasis in the Neotropics and forest-associated species. First, I conducted a literature review focusing on bat research studies conducted at landscape scales globally. I identified knowledge gaps, taxonomical and geographical biases, and summarized trends in research subjects, methodological approaches, and findings. I found that bat diversity hotspots were understudied and knowledge for responses to landscape for some bat families was completely lacking. Bat responses were highly species-specific and varied greatly, even among taxonomically closely-related species. However, intra-specific conditions (e.g., demographic, behavioral) also altered responses to landscape features both spatially and temporally. Next, I used a country-wide bat capture dataset and land cover and land use data layers to conduct a landscape analysis across the entirety of Nicaragua, a country in the Neotropics with high bat diversity. I quantified and compared landscape metrics that offered insight on the spectrum of tolerance to forest fragmentation among six bat species in the leaf-nosed family (Phyllostomidae). The results of this analysis quantified not only a difference in the tolerance to landscape fragmentation between habitat generalist (subfamily Stenodermatinae) and forest-specialist (subfamily Phyllostominae) species, but among the species within each group. This corresponded to empirical knowledge on these two major groups and provided further support about the associations of these species with their environment. Lastly, I used radio-telemetry and DNA metabarcoding to describe movement and diet of a forest habitat specialist and carnivorous bat (Vampyrum spectrum). I used natural history data to identify habitat and prey selection for this rare bat species listed as Near Threatened by the International Union for Conservation of Nature about which little is known. My observations in movement and roosting supported long-standing assumptions on the relationship of this rare species with mature forests. Activity patterns and diet of V. spectrum indicated an opportunistic foraging strategy, preying predominately on birds, other bat species, and terrestrial rodents. The information in these three chapters will help orient and prioritize areas of research. Additionally, our understanding about species responses to changes in the landscape structure will inform management and conservation policies that maximize the use of resources to retain important landscape conditions for bat diversity.

Item Type:	Thesis (Doctoral)
Publisher’s Statement:	© Copyright is held by the author. Digital access to this material is made possible by the Cline Library, Northern Arizona University. Further transmission, reproduction or presentation of protected items is prohibited except with permission of the author.
Keywords:	Bats; Habitat fragmentation; Landscape; Multi-level; Multi-scale; Tropical forests
Subjects:	Q Science > QL Zoology
NAU Depositing Author Academic Status:	Student
Department/Unit:	Graduate College > Theses and Dissertations College of the Environment, Forestry, and Natural Sciences > School of Forestry
Date Deposited:	22 May 2023 22:28
Last Modified:	22 May 2023 22:28
URI:	https://openknowledge.nau.edu/id/eprint/5901

Actions (login required)

IR Staff Record View

Downloads