Biology subjects

Strange, J. P.

Publications and source records attributed to Strange, J. P..

3 recordsLinked to original sources

bioRxiv2023

BUMBLE BEE RESPONSES TO CLIMATE AND LANDSCAPES: INVESTIGATING HABITAT ASSOCIATIONS AND SPECIES ASSEMBLAGES ACROSS GEOGRAPHIC REGIONS IN THE UNITED STATES OF AMERICA

Bumble bees are integral pollinators of native and cultivated plant communities, but species are undergoing significant changes in range and abundance on a global scale. Climate change and land cover alteration are key drivers in pollinator declines; however, limited research has evaluated the cumulative effects of these factors on bumble bee assemblages. This study tests bumble bee responses to climate and land use by modeling 1) occupancy (presence/absence); 2) species richness; 3) species-specific habitat requirements; and 4) assemblage-level responses across geographic regions. We integrated richness, abundance, and distribution data for 18 bumble bee species with site specific bioclimatic, landscape composition, and landscape configuration data to evaluate the effects of multiple environmental stressors on bumble bee assemblages throughout 433 agricultural fields in Florida, Indiana, Kansas, Kentucky, Maryland, South Carolina, Utah, Virginia, and West Virginia from 2018 to 2020. Increased prevalence of attractive crops was associated with increased bumble bee presence, while higher maximum temperature of warmest month and unattractive crops were linked to bumble bee absences. Bumble bee species richness was positively correlated with attractive crops and elevation but declined with precipitation of the wettest month. Moreover, species richness increased as maximum temperature of warmest month approached 29{degrees}C but declined at they rose to 36{degrees}C, suggesting a potential temperature threshold around 33{degrees}C. Distinct east vs. west groupings emerged when evaluating species-specific habitat associations, prompting a detailed evaluation of bumble bee assemblages by geographic region. Overall, climate and land use combine to drive bumble bee occupancy and assemblages, but how those processes operate is idiosyncratic and spatially contingent across regions. From these findings, we suggested regionally specific management practices to best support rich bumble bee assemblages in agroecosystems. Results from this study contribute to a better understanding of climate and landscape factors affecting bumble bees and their habitats throughout the USA.

ecology↗

bioRxiv2023

Homogenization of taxonomic, phylogenetic, and functional characteristics of bumble bee communities at regional scales in anthropogenic landscapes

Biotic homogenization has been documented following extensive anthropogenic landscape change such as urbanization and agriculture, but diverse native communities also have been reported in these ecosystems. Understanding the influence of landscape-level characteristics on processes of community assembly can inform how human-dominated landscapes shape the structure and composition of local communities, including important pollinators such as bumble bees (Bombus spp.). The objective of this study was to investigate multi-scale patterns of taxonomic, phylogenetic, and functional beta- diversity of bumble bees in greenspaces along an urban-agricultural gradient to understand landscape- scale constraints on processes of community assembly. Bumble bees were collected in greenspaces along an urban-agricultural gradient in Madison, WI, USA. Patterns of biotic homogenization were investigated using measures of beta-diversity and null models relative to a regional bumble bee species pool in a 100 km area surrounding the city. Nine of the expected 13 species from the regional pool were collected in greenspaces in urban and agricultural landscapes. At the regional scale, we found evidence of taxonomic, phylogenetic, and functional homogenization among bumble bee communities in urban and agricultural landscapes, with species that were smaller in size, had shorter wings, were less hairy, but had larger eyes and longer setae on the corbicula (pollen-carrying hind legs) being more common than expected based on null models. When we evaluated filtering from the anthropogenic species pools (i.e., urban and agricultural) to local greenspaces, we found nuanced differences among land cover types, wherein agricultural landscapes supported higher beta-diversity of bumble bee communities than expected while urban landscapes continued to show signals of homogenization. Overall, anthropogenic landscapes acted as a strong filter for bumble bees, broadly selecting for a subset of functionally similar and phylogenetically related species that resulted in homogenization of communities within the region. Our findings support a landscape-level approach to biodiversity conservation that promotes diversifying landscapes to support diverse pollinator populations. OPEN RESEARCH STATEMENTData and novel code associated with this submission are provided in an external repository to be evaluated during the peer review process and are available at https://github.com/kiperry/WI_Bumble_Bees. If this paper is accepted for publication, data and code will be permanently archived within a linked Zenodo repository.

ecology↗

bioRxiv2019

Projected climate change will reduce habitat suitability for bumble bees in the Pacific Northwest

Global climate change is the greatest environmental challenge of the modern era. The impacts of climate change are increasingly well understood, and have already begun to materialize across diverse ecosystems and organisms. Bumble bees (Bombus) are suspected to be highly sensitive to climate change as they are predominately adapted to temperate and alpine environments. In this study, we determine which bumble bee species are most vulnerable to climate change in the Pacific Northwest. The Pacific Northwest is a topographically complex landscape that is punctuated by two major mountain ranges and a labyrinth of offshore islands in the Salish Sea. Using standardized survey methods, our study documents the occurrence of 15 bumble bee species across 23 field sites in seven federal parks, historical sites, and monuments. Our results show that bumble bee community richness and diversity increases along an altitude gradient in these protected areas. Furthermore, NMDS analysis reveals that high altitude environments are composed of a unique group of bumble bee species relative to low altitude environments. Finally, based on an analysis of species distributions models that aggregate bioclimatic data from global circulation climate models with preserved specimen records, we discover that 80% of the bumble bee species detected in our survey are poised to undergo habitat suitability (HS) loss within the next 50 years. Species primarily found in high altitude environments namely B. vandykei, B. sylvicola, and B. bifarius are projected to incur a mean HS loss of 63%, 59%, and 30% within the federally protected areas, respectively. While the implementation of climate change policies continue to be a significant challenge, the development of mitigation strategies to conserve the most vulnerable species may be a tractable option for land managers and stakeholders of protected areas. Our study meets this need by identifying which species and communities are most sensitive to climate change.

ecology↗