Bombus sonorus
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Assessing the current distribution and taxonomic status of Bombus sonorus and Bombus pensylvanicus
The current Texas distributions of the Sonoran Bumble Bee (Bombus sonorus) and the American Bumble Bee (Bombus pensylvanicus), both designated a Species of Greatest Conservation Need by the Texas Parks and Wildlife Department, are not well understood due to limited monitoring efforts within their historic ranges. Additionally, the species status for B. sonorus has been debated for the past century, with some taxonomists classifying the group as a western morphological variant of B. pensylvanicus. The University of North Texas has received funding from the Texas Parks and Wildlife Department to quantify the contemporary distributions of B. sonorus and B. pensylvanicus in Texas, as well as clarify the taxonomic relationships between these species using next-generation DNA sequencing techniques. The results of our study will help to inform management decisions for the conservation of both B. sonorus and B. pensylvanicus in Texas and beyond. |
Current modeled distribution of Bombus fraternus
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Modeling Current and Future Statewide Bumble Bee Species Distributions
In Texas, three bumble bee species have been designated as Species of Greatest Conservation Need (SGCN) in the Texas Conservation Action Plan. In order to enhance conservation efforts for these species this project compiled current bumble bee presence data, including dates and locations of species sightings, from a variety of discrete sources into one central database. These data were then used to model statewide (Texas) species distributions for bumble bees using the computational software Maxent. This software outputs maps that are easily interpreted for widespread dissemination of knowledge and will provide the basis for identifying areas which present the best opportunities for conservation of bumble bee SGCN. We have extended this project to also model future distributions of bumble bees in Texas based on various climate change scenarios. This project was funded by a 2015 State Wildlife Grant from the Texas Parks & Wildlife Department. This work has been submitted for publication and is currently undergoing the peer-review process; the pre-print of this article can be found here. |
Bowling Green Community Garden in Denton, TX
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Use of Urban Green Spaces by Bumble Bees in Denton County
Urban sprawl, and associated habitat loss, has been implicated as a major driving force of pollinator declines, but some studies have suggested that green spaces within urban environments can serve as habitat islands that support bumble bee populations. We aim to assess the importance of urban green spaces as foraging grounds for bumble bees in Denton County, TX. By collaborating with the City of Denton, the Lake Lewisville Environmental Learning Area and local community gardens, we were able to sample eight sites of varying urbanization in Summer, 2013; this work resulted in the sampling of 450 unique individuals comprising two declining bumble bee species, B. pensylvanicus and B. fraternus. DNA samples, in the form of nonlethal toe clips, were also taken from each bee for the purpose of determining how many hives were sampled and to look at the genetic structure of local populations. This study revealed that a surprisingly large number of hives are visiting local green spaces in the area, and that individuals across the study area are part of a large genetic population. See my full dissertation here. |
Sampling sites of bumble bees in northeast Texas
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The Persistence of Bumble Bee Species in Northeast Texas
Two Bombus species historically found in northeast Texas, B. pensylvanicus and B. fraternus, have shown evidence of population declines in other parts of the United States, but information on the current status of this region’s populations is scarce. Through grants from the Texas Parks & Wildlife Department we have been able to assess the persistence of these species in northeast Texas. We performed roadside field surveys across 16 counties comprising 12,812 square miles of northeast Texas in 2013 and 2014 and compared these data to historic records from natural history collections. Both species were detected along surveyed roadsides and show no evidence of decline in the study region. These results provide a baseline for understanding the current status of these species in northeast Texas and suggest that northeast Texas roadsides are a potential starting point for implementing conservation actions. The final report for this project can be found here, and the peer-reviewed article can be found here. |