USING BAT GUANO TO DETERMINE SPECIES USE OF REDWOOD HOLLOWS ON THE NORTH COAST OF CALIFORNIA
|Amon J Armstrong; Humboldt State University; Amon.Armstrong@humboldt.edu; Dr. Joseph Szewczak|
Loss of roosting resources negatively affects bat populations. For sensitive species, such as the Townsend’s big-eared bat (Corynorhinus townsendii), determining roost locations and requirements is a critical component in conserving their habitat. Such cavity roosting bats on the North Coast of California are known to use hollows in large redwood trees. We examined the relative amount of use of basal tree hollows by different bat species at eight coastal redwood forest sites. Observations of bats were expected to be rare, and this was confirmed with just 13 observations in 1547 hollow visits. For this reason, bat guano was collected to determine roosting activity and species use (179 hollows visited monthly from 2017 to 2018). To identify species, DNA analysis was performed at the Northern Arizona University “Species from Feces” lab. Nine bat species and one species group were identified using hollows. Of 253 species identifications from 83 hollows, the most prevalent were Myotis californicus (28.5% of all identifications), the M. evotis-M. thysanodes group (17.4%), C. townsendii (17.0%), and M. volans (15.0%). These findings can inform land managers when planning conservation and management of redwood forests.
NOVEL DNA COLLECTION METHOD FOR IDENTIFICATION OF ROOSTING BAT SPECIES
|Rob Schell; WRA, Inc.; Schell@wra-ca.com; Katie Smith, Cheryl Dean|
Identification of North American microchiropteran bat species at roost sites, especially in urban or suburban environs, is challenging. Capture and acoustic detection methods are effective, but only when bats are present, and can result in disturbance to wildlife. Analysis of guano or other physical cues can be effective, but only when present. We investigated the efficacy of genetic analysis of residues left directly on roosting surfaces. At two sites in Northern California roosts were identified based on the presence of residues on surfaces with guano beneath them, and were swabbed for trace DNA. This method was then challenged against genetic analysis of guano and tissues present at the sample location to determine accuracy of the technique. This new technique has the potential to improve the ability to identify which species of bats have recently utilized roost, even when no animals are present, which will improve our ability to protect bats when roost sites must be disturbed. Further, it is cost effective and low risk to both animals and biologists. We encourage environmental professionals to consider utilizing this technique and contributing to evaluating its utility for various bat species in different habitat types.
GENETIC EVALUATION OF THE HISTORIC AND CURRENT DISTRIBUTION AND POSSIBLE VARIATIONS BETWEEN LASIURUS BOREALIS AND LASIURUS BLOSSEVILLII IN WESTERN NORTH AMERICA
|Zeinab (Rose) M Haidar; Humboldt State University; email@example.com;|
Recognized as having highly dynamic movements and specialized life histories, members of the genus Lasiurus, commonly named tree bats, have uncertain and disputed ranges. Several recent accounts of overlap, historic misidentification, and possible phylogenetic variations regarding two species of this genus; western red bat (Lasiurus blossevillii/Frantzii) and eastern red bat (Lasiurus borealis) in California, Arizona, Utah, and New Mexico have cast doubt on our understanding of their distribution, speciation, and assumed spatial allopatry. With the use of genetic sequencing utilizing tissues collected from museum and field specimens throughout California and adjoining states we can infer historic and current distribution and identify genetic variation. Appropriate species classification by region is currently being achieved utilizing mitochondrial DNA, and a more comprehensive analysis at the nuclear and genomic level will be accomplished through lower coverage whole genome sequencing. All samples include morphometrics and pelage records for identifying possible congruence in segregating the species in hand. Currently we have confirmed the existence of Lasiurus borealis in 3 counties in California. Pelage and morphometrics have shown overlap but statistically significant numbers for analysis have not been reached. The results acquired from this study will strengthen our limited understanding of this dynamic group by inferring on their basic biology, their distinctive characteristics, and altogether aid in future conservation and research.
HONEYCREEPER HOSTS: TESTING THE EFFECTS OF DIET, ENVIRONMENT, AND GENETIC RELATEDNESS ON THE GUT MICROBIOME USING A CLASSIC EXAMPLE OF ADAPTIVE RADIATION
|Maria S Costantini; University of Hawaii at M?noa; firstname.lastname@example.org; Matthew C.I. Medeiros, Elin Videvall, Michael G. Campana, Robert C. Fleischer, Floyd A. Reed|
A component of endangered species management that has historically been overlooked is the relationship between a host and its gut microbiome. In animals, the microbiome has a strong influence on the health, fitness, and behavior of their hosts. The composition of the microbiome community can be influenced by an individual’s diet, environment, and evolutionary history. This project aimed to explore the drivers of microbiome variation across the remaining species of the Hawaiian honeycreeper lineage. We used amplicon-based sequencing of the 16S rRNA gene to characterize the gut microbiome of Hawaiian honeycreepers across the remaining lineage in relation to diet, geography, and genetic relatedness. Fecal samples, a proxy for the gut, were collected from 14 of the remaining 17 honeycreeper species and sequenced using the Illumina MiSeq platform. Preliminary results indicate that sampling island appears to be the major driver of microbiome variation, while diet also plays some role. The dendrogram of host-associated microbiomes did not recapitulate the host phylogenetic tree; indicating that phylogeny does not strongly influence microbiome variation. These results provide a baseline for microbiome work in Hawaiian honeycreepers, which will prove essential for conservation planning as species are targetted for captive breeding and translocation.
DIET OF BARRED OWLS IN CALIFORNIA ELUCIDATED WITH HIGH-THROUGHPUT-SEQUENCING
|Nick Kryshak; University of Wisconsin - Madison; email@example.com; Emily D. Fountain, Daniel F. Hofstadter, Brian P. Dotters, Kevin N. Roberts, Connor M. Wood, Kevin G. Kelly, Amy K. Wray, H. Anu Kramer, John P. Dumbacher, John J. Keane, M. Zachariah Peery|
Barred Owls (Strix varia) continue to expand through the Pacific Northwest and into the Sierra Nevada, California, threatening native species. In this study, we conducted genetic-based dietary analyses using intestinal samples from invasive barred owls collected at the front end of their California expansion to better understand potential impacts on wildlife communities. Using a diverse panel of DNA amplifying primers and high-throughput-sequencing, we successfully screened the intestinal contents of 124 barred owls, detecting a broad diet of 78 unique prey types (48 vertebrates and 30 invertebrates). Commonly consumed taxa of note included Douglas squirrel (Tamiasciurus douglasii), Northern flying squirrels (Glaucomys sabrinus), Sierra and Pacific tree frogs (Pseudacris sierra and P. regilla), dusky footed woodrats (Neotoma fuscipes), and several game and domestic species. Barred owl prey consumption demonstrates the potential for exploitative competition with spotted owls (Strix occidentalis), but also potential competition with sensitive species including fishers (Pekania pennanti) and Northern goshawks (Accipiter gentilis). Diet composition varied across an elevation gradient, based on forest conditions, and between the Sierra Nevada and Klamath regions. Our findings indicate that barred owls – as generalist predators – will not serve as ecological replacements for spotted owls should they continue to increase in relative abundance.
AMPHIBIAN DIVERSITY ASSESSMENT OF NORTHERN CALIFORNIA'S LOST COAST REGION.
|Brian R. Hudgens; Institute for Wildlife Studies; firstname.lastname@example.org; Elizabeth McAlpine, Megan Berberich, Matthew Bouffard, Leah Thayer|
Amphibians are widely believed to be highly vulnerable to population declines, with nearly one third of all amphibian species at risk of global extinction. The first step in understanding and preventing amphibian declines is knowing where amphibians occur. The Lost Coast of northern California is a rugged and remote area, located in Humboldt and Mendocino counties, where little is known about regional amphibian diversity. We conducted a stream-dwelling amphibian survey during June-August, 2021 to characterize the diversity and distribution of amphibians of the Lost Coast. We conducted three visual encounter surveys and collected environmental DNA (eDNA) samples at 29 sites within the Sinkyone Wilderness State Park, King Range National Conservation Area and Lost Coast Headlands. We found 12 native amphibian species and 1 native turtle, and no nonnative amphibian or turtle species. We recorded 8-10 species during each round of visual encounter survey, and 6 species from eDNA samples. One species was only detected from eDNA samples. Our results demonstrate that even when targeting a limited suite of taxa, such as stream-dwelling amphibians, rapid assessments of biodiversity should include repeated surveys using a variety of methods.
TORRENT IN A BOTTLE: USING ENVIRONMENTAL DNA TO DETECT COLUMBIA AND CASCADE TORRENT SALAMANDERS IN THE PACIFIC NORTHWEST
|Christopher Cousins; Oregon State University; email@example.com; Jennifer Allen, Tiffany Garcia, Dede Olson, Brooke Penaluna|
Cascade (Rhyacotriton cascadae) and Columbia torrent salamanders (Rhyacotriton kezeri) are stream amphibians whose monogeneric family is endemic to the Pacific Northwest. Both species are being considered for ESA listing as their headwater stream habitat is vulnerable to habitat loss from effects of climate change. In order to provide information about current distribution and validate habitat suitability models, we performed range-wide physical surveys at 96 sites (48 sites per species: 24 in Oregon and 24 in Washington) in the spring and summer of 2019. We took eDNA samples from 12 sites per species, spread spatially across each species range. Species specific primers were developed for both R. kezeri and R. cascadae, and we used quantitative PCR (qPCR) on samples to determine if eDNA was an appropriate survey method for each species. We used Bayesian hierarchical models to determine the effects of site conditions on detectability at the site, sample, and PCR replicate levels. We observed differences in detection rates across sites, and more work is needed to determine what issues are most impactful to detectability. Our work provides a noninvasive passive sampling method for these threatened salamanders that can be used to track future occupancy shifts.