2020 Exploration and Field Research Grant Recipients
Lindsay Barranco (M.S.), University of Maryland, Entomology, “Evaluating native bee abundance, diversity and nesting preferences in small-scale wildflower strips”, Maryland
Ground nesting bees are important pollinators and 70% of bee species worldwide nest within the ground, yet little is known about bee nesting preference. This project will measure the abundance, diversity and nesting preferences of ground solitary bees within wildflower strips, bare soil, and turf grass, and “scratched” bare ground areas within these substrates, and evaluate how management practices (i.e., weekly turfgrass mowing), impacts nesting preference. The abundance, diversity and nesting preference by use of emergence traps, pan traps and net sweeping will be compared. Emergence traps have the unique benefit of capturing ground nesting bees upon emergence or nest building. There exists a small body of research that has identified ground nesting bee preference via emergence traps in agricultural lands, prairies and forests but none in the mid-Atlantic area that look at bare ground, wildflowers and turf grass, or the creation of scratched bare areas within or the impacts of grass management. This research will contribute to this body of research by identifying how land use can be augmented for native bee nesting in order to increase pollinator habitat.
Hannah Clipp (Ph.D.), West Virginia University, Forestry and Natural Resources, “Optimizing wildlife openings for game birds and overall avian diversity”, West Virginia
In forested landscapes, wildlife openings created and maintained by land managers provide habitat and food resources for disturbance-dependent, early-successional game species, such as wild turkey, ruffed grouse, and American woodcock. Though managers tend to focus on game birds, wildlife openings can also benefit a myriad of bird species and guilds, including species of conservation concern, depending on local habitat features and landscape-level factors. Yet little effort has been made to investigate how to optimize wildlife openings to attract a full spectrum of bird species throughout spring and summer. The purpose of this study is to examine the use of wildlife openings by game birds, breeding songbirds, and post-breeding songbirds in response to site- and landscape-level wildlife opening attributes. In the spring and summer of 2019, preliminary data included species-specific and community-wide point count surveys, game cameras, autonomous recording units, and mist-netting surveys to sample bird communities in 65 wildlife openings within the Monongahela National Forest in eastern West Virginia. Data collection and statistical analyses are ongoing, but the final results will be used to assist land managers in designing and maintaining wildlife openings that simultaneously support target game bird populations and promote a diverse suite of songbirds.
Alexandra Fireman (M.S.), University of Maryland, Chesapeake Biological Laboratory, “On the shell of the turtle: Identifying dietary patterns of the Caribbean hawksbill sea turtle”, Antigua, Maryland
The hawksbill sea turtle is critically endangered, and the extinction of this keystone species could cause severe disruption to their vulnerable coral reef habitats. Understanding the hawksbill’s ecology is critical for effective conservation. However, as a long-lived species, hawksbills can be difficult to study in their oceanic habitats. While elusive in the water, during the nesting season, females crawl onto beaches, providing an accessible opportunity for study of the species. This research plans to use this nesting period to learn about both their reproductive lives on land and their in-water lives. This will be achieved by using 1) diet markers in turtle tissue, 2) satellite tracking data to gain insights into their foraging habitats, and 3) long-term reproductive data to understand individual success. The research will focus on a consistently monitored population of nesting hawksbills in Long Island, Antigua. This work will allow for identification of marine areas that produce reproductively successful female hawksbills. Understanding where the most successful hawksbills live, and their diet allows for targeted conservation of their habitat. This project will have direct conservation impacts for the Long Island hawksbill population but can also serve as a model for the Caribbean and even global populations of hawksbills.
Dawei Han (Ph.D.), University of Maryland, Biology, “Sound localization and hearing sensitivity of the barking gecko (Ptenopus garraulus)”, South Africa
Localization of sound sources is a fundamental task of the auditory system. In mammals, the two ears are unconnected pressure receivers, and sound direction is computed from binaural interactions in the brain. Directional hearing is different in lizards and frogs because the two eardrums interact acoustically through connected middle ear cavities, leading to strongly directional eardrum vibration. Therefore, these animals should have a high capacity to differentiate between nearby sound sources. This prediction has been hard to test in lizards, since most are ambush, or sit-and-wait predators and typically do not vocalize. This study will take advantage of the behavior of a highly vocal lizard species, the barking gecko (Ptenopus garrulus) to test their ability to localize sound. The hypothesis is that female geckos will orient towards male vocalizations during the breeding season by walking in a zig-zag pattern, which has been documented frequently in animals with coupled ears. Auditory brainstem responses will be measured to compare hearing sensitivity of barking geckos to other vocal lizard species. Behavioral evidence for sound localization in extant lizards will provide insight into the early evolution of hearing and sound localization in ancestral land vertebrates, which possessed similarly coupled ears.
Rebecca Hill (Ph.D.), University of Maryland Baltimore County, Biological Sciences, “Vocal development in Grasshopper Sparrows”, Kansas, Maryland
Vocal development is a relatively well studied process in model songbirds such as zebra finches and canaries. This study will focus principally on vocal development in a less studied North American species of conservation concern, the grasshopper sparrow (Ammodramus savannarum). Grasshopper sparrows appear to show a different pattern of learning than most model songbird species, exhibiting an improvisational rather than imitative process for establishing their adult song repertoire. Furthermore, preliminary data suggests the timing of crystallization (or fixation of the adult repertoire) appears to occur along different trajectories depending on song type A methodology to quantify the timing of crystallization using recordings of grasshopper sparrows throughout the song learning period will be developed. In addition, a series of experiments will be conducted that is intended to manipulate the timing of the crystallization process in a subset of these birds using both natural steroid hormones and steroid-mimicking endocrine disruptors in pesticides to understand how song variation and song aberration may occur in the field. Should the effects of endocrine disrupters in pesticides be linked to abnormal song production and decreased ability to find mates and reproduce would provide reasoning to limit pesticide use containing endocrine disrupters near habitats of grasshopper sparrows. This could lead to more reproductive success in an endangered species and ultimately an increase in a population that has been greatly declining for decades.
Victoria Lockwood (Ph.D.), George Washington University, Center for the Advanced Study of Human Paleobiology, “Arboreal support diameter choice: Biomechanics, ergonomics, and comparative anatomy”, Tanzania, Washington, DC
This project will assess to what extent locomotor behavior can be inferred from hand bone morphology. The extent that morphology implies function has led to debate, particularly about the evolution of bipedalism. Using a chimpanzee referential model, the investigation will focus on these questions: 1) Is the way chimpanzees use arboreal spaces reflected in their hand skeletal morphology? 2) If so, can this relationship be used to retrodict the arboreal locomotor capabilities of extinct hominins? Some primate species display a preference for certain sized diameters during arboreal locomotion. A detailed analysis of the hand-support interaction is needed to interpret these behavioral decisions. A primate optimal diameter equation will be applied to chimpanzee behavioral observations (Gombe National Park, Tanzania), to assess how individuals use arboreal supports, which will then be tested against skeletal hand morphology. Previously collected modern human data and ergonomic equations will be used to identify high-pressure areas of the chimpanzee hand. The morphology of these areas will be compared to the whole hand. This will allow an interpretation whether, and how, early hominins used their hands to exploit arboreal resources.
Kinsey Tedford (Ph.D.), University of Virginia, Environmental Sciences, “Restoring and sustaining Virginia’s oyster reefs: spatial drivers of oyster populations across multiple spatial scales”, Virginia
Restoration of oyster reefs has the potential to improve the conservation status of depleted oyster populations while enhancing water quality, shoreline protection, biodiversity, and fisheries production. However, oyster restoration has experienced mixed success and lacked clear conclusions on the relative importance of oyster recruitment and survival. This study includes a series of large-scale field experiments to examine the relative importance of abiotic and biotic factors in determining the success of Eastern oyster on restored reefs in coastal Virginia. Specifically, the experiments will test how landscape setting, broad-scale environmental variables, and within- habitat complexities interact to structure oyster recruitment and survival, and their associated communities. The density and size of oysters recruiting to ceramic plates on restored reefs that span 22 km will be measured. Manipulative field experiments involving predator- exclusion cages to assess how the survival of juvenile and adult oysters varies across a landscape with strong differences in hydrodynamic conditions will be conducted. The results from this study will broaden the knowledge of coastal ecology and improve oyster conservation by providing insight on how environmental and geospatial variables mediate the success of restoration actions.