Biology subjects

Lichtenberg, E. M.

Publications and source records attributed to Lichtenberg, E. M..

10 recordsLinked to original sources

bioRxiv2026

A workflow to gather, clean, and standardize species occurrence records at scale for conservation applications

Biodiversity declines and pressing threats to wildlife necessitate data-driven approaches for conservation and management planning. Natural resource agencies, conservation practitioners, and researchers increasingly leverage digital species occurrence records. However, we still lack user-friendly and flexible tools to aggregate, clean, and standardize such data. These tools are particularly needed for speciose groups like invertebrates and plants whose natural histories are poorly or unevenly known. To provide such a tool and overcome limitations of existing options, we developed a workflow in R that encompasses the entire process of aggregating, cleaning, and standardizing occurrence records within one free software platform. It additionally can return information useful for assessing species' conservation status. Key features include user friendliness, flexibility in data sources and filtering, handling large volumes of data or multiple species, and high transparency. We demonstrate workflow functionality focusing on Texas native bees. We combined bee data from the Global Biodiversity Information Facility (GBIF) and several smaller datasets, then cleaned and standardized the combined dataset including removing duplicates. Processing 145,870 bee records took about an hour on a standard-configuration government computer. We used the resulting records in three case studies that demonstrated various uses conservation practitioners commonly implement. Case study 1 compiled a species list for Denton County, the second described phenology of bumble bees (Bombus genus) in the Dallas-Fort Worth Metroplex, and the third assessed conservation status of Bombus pensylvanicus. Our workflow greatly facilitates addressing a range of questions at various spatial and temporal scales from one vetted dataset that are tailored to the needs of a specific research objective, management question, municipality, or audience.

ecology↗

bioRxiv2026

Rediscovery of the eucerine bee Xenoglossa cressoniana in Texas

Xenoglossa cressoniana, also known as Tetraloniella cressoniana or Xenoglossodes cressoniana, is a eucerine bee known mainly from the US Great Plains. The species was described from a female collected somewhere in Texas in the early 1900s. Here, we report local rediscovery of this species in Texas and a new state record for Oklahoma after over a century with no intervening observations in either US state. While surveying north Texas ranches, we collected six specimens, including both males and females, at five sites northwest of the Dallas-Fort Worth Metroplex. In Oklahoma, we collected two females within a single nature preserve. Xenoglossa cressoniana's range, the Great Plains and parts of the deep South, covers a large proportion of the United States that has been historically overlooked by most bee researchers. This report highlights the critical need for increasing data from under-sampled regions including the Great Plains and from private lands, even within a heavily sampled country such as the US.

ecology↗

bioRxiv2026

Diversifying stocking practices within rangelands supports diverse plant-pollinator communities and interactions

Understanding how management alters species' biodiversity and interactions is critical for sustainable agriculture. This can be especially important for rangelands, grasslands used for livestock grazing that cover 30% of land worldwide. In rangelands, ranchers need to maximize livestock production while supporting healthy ecosystems. Grazing management can alter the impact of livestock by varying grazing timing and intensity, but its ecological impacts remain poorly understood. One critical function that may be supported in these systems is pollination; how rangeland management may alter this ecosystem service is not systematically understood. We investigated how rotational stocking, where livestock are rotated among pastures, affected plant and pollinator communities and plant-pollinator interactions using working ranches in the Southern Great Plains. Sites were managed through continuous stocking or rotation with low or high frequency. We found that high-frequency livestock rotation supported greater flower abundance, and consequently greater pollinator abundance. Pollinator orders varied in their responses to management with Hymenoptera directly responding to management, and Coleoptera and Lepidoptera responding indirectly via changes in flower abundance. Community-level changes produced more specialized interaction networks and higher interaction diversity. These community changes, and resulting species turnover, led to high interaction turnover across rangeland sites. This suggests that a mosaic of management strategies likely diversifies habitat and helps support plant and pollinator biodiversity at the landscape scale. This study demonstrates that rangelands can support plants, pollinators, and their interactions, particularly when managed with high-frequency rotational stocking.

ecology↗

bioRxiv2026

How comparable across management goals are grassland monitoring methods?

QuestionsEcological monitoring, repeated collection of ecological data, is essential to document how ecosystems respond to change. In grasslands, different vegetation monitoring protocols are used across disciplines, making it difficult to address multiple management objectives or research questions. We asked four questions about how three common vegetation monitoring protocols compare. (1) How do the protocols differ in how they collect data? (2) How do the protocols differ in their utility? (3) In what ways do vegetation measurements quantitatively differ across protocols? (4) What are each protocols strengths? LocationThis study was conducted on working ranches in the Southern Great Plains with vegetation consisting mainly of native forbs and grasses. MethodsWe implemented three protocols at each site: (1) the Rangeland Analysis Platform (RAP), (2) the Grassland Effectiveness Monitoring (GEM) protocol, and (3) a typical pollinator ecology survey protocol. We qualitatively compared each protocols utility and quantitatively compared cover measurements that each produced. ResultsAll three protocols displayed positive associations within cover categories, but differed in actual cover measurements. The RAP protocol, which uses remote sensing, measured the highest total vegetation cover. The GEM protocol, a line-point intercept method, had more capability to capture fine-scale cover patterns. The GEM protocol measured the most bare ground while the Pollinator protocol measured more forb coverage. ConclusionFine-scale methods like the GEM protocol are most appropriate to address objectives that require capturing small patterns that would otherwise be overlooked with methods like quadrats or remote sensing. Remote sensing is advantageous when monitoring large areas or inaccessible land, but may over-estimate cover. The Pollinator protocol is best equipped to address questions regarding flower abundance and richness. Similarities among protocols can facilitate synergy across disciplines for more effective monitoring. We emphasize the importance of denoting a clear scale and scope of monitoring objectives before selecting methods.

ecology↗

bioRxiv2024

Social information use across trophic guilds

Animals use social information gathered by observing other individuals to adjust their behavior to better match the environment and improve fitness. Many insects use social information in various contexts. Bees improve their foraging efficiency by using social information from conspecifics to gauge nectar availability. Bees frequently encounter various heterospecific flower visitors, including those from different trophic groups such as nectaring predators. These heterospecifics may provide valuable information about nectar availability. We determined how bumble bees (Bombus impatiens) use visual social information from lady beetles (Hippodamia convergens). Lady beetles are predators of small insects, but not bees, and also visit flowers to consume floral nectar to increase their reproductive output. Using laboratory-maintained bumble bees freely flying in arenas, we tested if bees could (1) innately recognize lady beetles as sources of social information about nectar, and (2) learn to use lady beetles to gauge nectar availability. Bees did not innately recognize lady beetles as a source of social information. They correctly learned to associate conspecifics with the presence and absence of food, but learned to associate lady beetles only with the presence of food and not the absence. Our results demonstrate social learning across species and trophic guilds, but suggest limits to when and how bees generalize social information from diverse heterospecific flower visitors.

animal behavior and cognition↗

bioRxiv2024

Local nesting resources rather than floral food alter ground-nesting bee communities in grazed habitats

O_LIUnderstanding how the availability of both trophic and non-trophic resources impacts key ecosystem service providers is crucial for informing conservation efforts. Non-trophic resources such as shelter can play critical roles in ecosystem function and resilience by affecting predation and pathogen rates, reproductive success, and interspecific interactions. However, non-trophic resources are often overlooked. This holds true for insect pollinators; impacts of shelter on community dynamics and pollination remain poorly understood. C_LIO_LIBecause the majority of bee species spend most of their lives underground, we explored whether nesting habitat characteristics are key drivers of ground-nesting bee abundance, diversity, and community composition. We additionally compared impacts of aboveground versus belowground nesting habitat characteristics, as the latter have received significantly less attention. Nesting habitat characteristics we considered included bare ground cover; and soil texture, compaction, and depth. We also included floral abundance and richness. We focused on rangelands, natural or semi-natural grasslands that are managed for livestock grazing, where management can dramatically alter trophic and non-trophic resources. Thus, we also investigated impacts of grazing management on bee habitat. C_LIO_LIWe found that belowground, but not aboveground, nesting habitat characteristics were important for ground-nesting bee assemblages. Ground-nesting bee abundance and richness were highest at sites with sandier and less compacted soils. C_LIO_LIOur results suggest that livestock grazing management may indirectly impact ground-nesting bee abundance through impacts on floral abundance. Sites with longer grazing rest periods had higher floral abundance, and sites with higher floral abundance supported more ground-nesting bees (but not more bee species). C_LIO_LIPolicy implications: Our study highlights the importance of considering non-trophic resources in conservation and restoration management. Managers should be cautious in using an aboveground measure such as bare ground as an indicator of bee habitat quality. Rather, we recommend that belowground habitat characteristics such as soil texture and compaction be included in habitat quality assessments. Evidence-based rangeland conservation and restoration planning may need to manage for ground-nesting bees preferred levels of soil compaction. Additionally, management-insensitive habitat characteristics such as soil texture may be important considerations for site prioritization in pollinator habitat conservation and restoration efforts. C_LI

ecology↗

bioRxiv2024

Floral visitors differentially respond to local and landscape grassland features

O_LIPredicting how habitat composition alters communities of mobile ecosystem service providers remains a major challenge in community ecology. This is partially because separate taxonomic groups that provide the same service may respond uniquely to changes in habitat and associated resource availability. Further, the spatial scale at which habitat features impact each group can vary. Failure to account for these differences significantly limits the ability to quantify shared versus contrasting responses to habitat for important ecosystem service-providing groups. C_LIO_LIWe investigated the impacts of local (habitat patch level) and landscape features in the US Southern Great Plains on groups of pollinating insects with different basic biologies: Coleoptera, Diptera, Hymenoptera, and Lepidoptera. Habitat features included local flower and shelter resources as well as landscape-scale semi-natural habitat. C_LIO_LIWe found that bare ground supported more Hymenoptera and Lepidoptera but fewer Diptera, while more diverse flower communities supported more Hymenoptera but fewer Coleoptera. Interestingly, given that this study occurred in a grassland system, forest cover in the surrounding landscape more strongly affected pollinator diversity than grassland cover did. Landscapes with more woodland had higher Coleoptera and Diptera richness. C_LIO_LIOur results highlight that pollinator conservation and sustainable land management depend on understanding the habitat needs, including shelter, of diverse pollinators. Because taxa can have opposite responses to specific habitat features or scales, providing a range of grassland management practices (e.g., variety in the timing and type of biomass removal) may be the most effective approach to support the broader pollinator community. C_LI

ecology↗

bioRxiv2023

BeeDC: An R package and globally synthesised and flagged bee occurrence dataset

Species occurrence data are foundational for research, conservation, and science communication, but the limited availability and accessibility of reliable data represents a major obstacle, particularly for insects, which face mounting pressures. We present BeeBDC, a new R package, and a global bee occurrence dataset to address this issue. We combined >18.3 million bee occurrence records from multiple public repositories (GBIF, SCAN, iDigBio, USGS, ALA) and smaller datasets, then standardised, flagged, deduplicated, and cleaned the data using the reproducible BeeBDC R-workflow. Specifically, we harmonised species names (following established global taxonomy), country names, and collection dates and we added record-level flags for a series of potential quality issues. These data are provided in two formats, "cleaned" and "flagged-but-uncleaned". The BeeBDC package with online documentation provides end users the ability to modify filtering parameters to address their research questions. By publishing reproducible R workflows and globally cleaned datasets, we can increase the accessibility and reliability of downstream analyses. This workflow can be implemented for other taxa to support research and conservation.

ecology↗

bioRxiv2021

Differential effects of soil-based agricultural diversification on arthropods and crop yield

Many agricultural management tactics, such as reduced tillage, aim to promote biodiversity and ecosystem services. Responses to such tactics can be context dependent, however, and differentially impact (i) functional groups of service-providing organisms and (ii) crop yields. In canola (Brassica napus L., B. rapa L.) crop fields we assessed how soil tillage and landscape context (amount of semi-natural habitat within 1 km of each field) affected arthropod biodiversity and crop yield. We assessed effects of full (multiple tillage passes that leave soil surface bare), intermediate (tilled once and some stubble remains), or no (seed planted directly into last years stubble) tillage on functional groups with unique diets and reproductive strategies: (i) herbivores, (ii) kleptoparasites, (iii) parasitoids, (iv) pollinators, and (v) predators. Effects of tillage and landscape context on arthropod abundance and diversity varied across functional groups. Pollinators responded strongest to tillage, benefitting from intermediate tillage. Predators and herbivores responded strongly to landscape context, as both were more abundant in landscapes with more semi-natural habitat. Our results suggest natural history differences among functional groups mediate effects of landscape context on biodiversity. However, variation in arthropod communities had little effect on canola crop yield. The effects of soil management practices on aboveground arthropods are complex, and practices thought to increase some aspects of agricultural sustainability may not be beneficial in other contexts. Identifying practices such as intermediate tillage that may increase soil quality and arthropod diversity is a key to designing agricultural ecosystems that will effectively benefit both biodiversity and human well-being.

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↗