Mendocino County Research Articles

Using multiple scales of movement to highlight risk–reward strategies of coyotes (Canis latrans) in mixed‐use landscapes

AbstractMany wildlife species vary habitat selection across space, time, and behavior to maximize rewards and minimize risk. Multi‐scale research approaches that identify variation in wildlife habitat selection can highlight not only habitat preferences and risk tolerance but also movement strategies that afford coexistence or cause conflict with humans. Here, we examined how anthropogenic and natural features influenced coyote (Canis latrans) habitat selection in a mixed‐use, agricultural landscape in Mendocino County, California, USA. We used resource selection functions and hidden Markov models to test whether coyote selection for anthropogenic and natural features varied by time of day or by behavioral state (resting, foraging, and traveling). We found that coyotes avoided development, but, contrary to our expectations, coyotes selected for roads, agriculture, and areas with risk of human encounter and rifle use regardless of diel period or behavioral state. While traveling, coyotes increased selection for roads and avoided ruggedness, indicating that unpaved roads may enhance connectivity for coyotes in mixed‐use landscapes. Finally, we found that coyotes selected for mountain lion habitat when resting and at night, signifying that risk from natural predators was not a factor in habitat selection at coarse scales. Coyote habitat selection for places and times associated with human activity, without variation across scales, signals a potential for conflict if coyotes are perceived by people as a nuisance.

Interactive abiotic and biotic stressor impacts on a stream-dwelling amphibian.

Organisms within freshwater and marine environments are subject to a diverse range of often co-occurring abiotic and biotic stressors. Despite growing awareness of the complex multistress systems at play in aquatic ecosystems, many questions remain regarding how simultaneous stressors interact with one another and jointly impact aquatic species. We looked at multistress interactions in a protected stream ecosystem in Mendocino County, California. Specifically, we examined how diurnal temperature variation, turbidity, and predator cues altered the movement speed of larval Pacific giant salamanders (Dicamptodon tenebrosus). In a second experiment, we looked at how simulated low-flow summer conditions impact the expression of heat-shock proteins (HSPs) in the same species. Larvae moved almost one and a half times faster in the presence of chemical cues from trout and suspended sediment, and almost two times faster when both sediment and trout cues were present but were only marginally affected by temperature and visual cues from conspecifics. Interestingly, the order of stressor exposure also appeared to influence larval speed, where exposure to sediment and trout in earlier trials tended to lead to faster speeds in later trials. Additionally, larvae exposed to low-flow conditions had more variable, but not statistically significantly higher, expression of HSPs. Our findings highlight the potential interactive effects of an abiotic stressor, sedimentation, and a biotic stressor, and predator chemical cues on an ecologically important trait: movement speed. Our findings also demonstrate the likely role of HSPs in larval salamander survival in challenging summer conditions. Taken together, these findings show that larval D. tenebrosus responds behaviorally to biotic and abiotic stressors and suggests a possible pathway for physiological tolerance of environmental stress. Consideration of multistress systems and their effects is important for understanding the full effects of co-occurring stressors on aquatic organisms to guide appropriate conservation and management efforts based on ecologically relevant responses of organisms within an environment.

Social vulnerability and climate risk assessment for agricultural communities in the United States

Floods and droughts significantly affect agricultural activities and pose a threat to food security by subsequently reducing agricultural production. The impact of flood events is distributed disproportionately among agricultural communities based on their socio-economic fabric. Understanding climate-related hazards is critical for planning mitigation measures to secure vulnerable communities. This study introduces a holistic approach for evaluating the combined risks associated with drought and flood hazards for agricultural communities in the United States. It accomplishes this by merging social vulnerability indicators with data on drought and flood exposure, enabling the identification of the most susceptible agricultural communities. The research seeks to offer valuable insights into the vulnerability of agricultural communities across the United States. It fills a vital research gap by conducting a comprehensive nationwide assessment of social vulnerability, considering expected annual losses related to both flood and drought hazards, and amalgamating social vulnerability with these expected annual losses. The analyses were conducted by adapting datasets and methodologies that are developed by federal institutions such as FEMA, USACE, and USDA. The study identified the 30 most socially vulnerable counties and assessed their exposure to drought and flooding, finding that Mendocino, Sonoma, Humboldt, El Dorado, Fresno, and Kern counties in California had the highest drought exposure and expected annual losses, with Humboldt (CA) and Montgomery (TX) having the highest combined risk. The study estimated over $1 billion in crop damage, with California experiencing the greatest losses, primarily affecting a diverse range of crops, while the Midwest was primarily impacted in terms of major crop types. The findings of this study can serve as supportive information for policymakers to better understand climate risks in agricultural communities and identify where risk mitigation activities should be allocated.

Economic Governance of Cannabis: The Implications of Polycentric Governance in Mendocino County

The 2016 passage of California’s Proposition 64, legalizing recreational (adult-use) cannabis, was justified ex ante in part for its potential to encourage restorative justice and positive local and state economic outcomes. But are the local institutions administering Proposition 64 achieving these aims? We address this question via a two-year case study of Mendocino County’s polycentric cannabis governance system using a mixed methods approach including archival analysis, cannabis industry and governance system interviews, and participant observation. Evidence from our case study suggests that Mendocino’s ability to achieve these goals is hampered by three quasi-market failures: interjurisdictional conflict, coproduction deficits, and devolution without adequate fiscal decentralization. A major driver in these quasi-market failures is the substantial regulatory and enforcement responsibility this governance system places on local government. We conclude by discussing some institutional structures that may address these failures.

Northern spotted owl nesting habitat under high potential wildfire threats along the California Coastal Redwood Forest

Large and severe wildfires, exacerbated by climate change and human behavior, are occurring more frequently in many forests across the western United States. While wildfire is a natural part of most terrestrial ecosystems, rapidly changing fire regimes have the potential to alter habitat beyond the adaptive capabilities of species. Spatial assessments of wildfire risks to species habitat may allow managers to pinpoint locations for management activities. To illustrate this, we spatially assessed wildfire risk within habitat that supports the nesting activity of the federally threatened northern spotted owl (Strix occidentalis caurina) in the California redwood coast ecoregion. To accomplish this, we built a scale-optimized ensemble nesting habitat suitability model and identified habitat with the highest wildfire hazard potential. Percent canopy cover at 100-m scale, slope at 400-m scale, and January precipitation at 800-m scale were the most influential environmental covariates for predicting northern spotted owl nesting habitat. Nearly 60% of nesting habitat was predicted to be at high or very high (>1986 index value) wildfire risks. We identified three areas in the Maple Creek Area of Humboldt County, Jackson State Demonstration Forest in Mendocino County, and Point Reyes National Seashore in Marin County, California with a high concentration of nesting habitat that are at a very high risk of experiencing high severity wildfires. We recommend these areas be targeted for future research to understand the impact of wildfire on northern spotted owl as well as management attention.

First report of root and crown rot caused by Armillaria gallica on Cannabis sativa in California, U.S.A.

In October 2018, symptoms of leaf necrosis, wilted shoots, and stunted growth were observed on the upper portion of the 7-month-old cannabis (Cannabis sativa L.) plants in Mendocino County, California, U.S.A. Foliar symptoms were followed by a rapid death of the plants within 24 hours. Out of 200 affected plants, 80% (160/200) were symptomatic. All affected plants were grown in non-woven polypropylene containers (Smart pots, Oklahoma, USA) set directly on the ground approximately 3 m apart outdoors, surrounded by native forest (Quercus spp., Pseudotsuga menzeisii). Closer examination of the C. sativa plants revealed diagnostic signs of Armillaria root disease: white mycelial fans at the base of the woody stem (root collar) and abundant rhizomorphs on the roots and root collar (Supplementary Fig 1A). Also, both woody roots and the root collar exhibited severely rotted wood. Rotted wood, mycelial fans, and rhizomorphs (n=20) were surface sterilized with 0.6% sodium hypochlorite, rinsed with sterile water, and plated on PDA amended with tetracycline (1 mg/L). Sixteen cultures with morphological characters of Armillaria sp. (regular colony margin, no spore structures, no clamp connections) were recovered (Baumgartner et al., 2011). Species identity was confirmed by sequencing the internal transcribed spacer (ITS) region of rDNA and the translation elongation factor subunit 1-alpha (TEF1a) loci (White et al. 1990, Baumgartner et al 2010). Sequences (GenBank nos. MT248417 and MT259788) were compared with those in the NCBI GenBank database using a BLAST search, revealing 876/881bp matching with Armillaria gallica ITS sequence, GenBank no KP960553, and 146/150bp matching with TEF1a sequence from a North America A. gallica isolate, GenBank no. JF895844 (Brazee et al., 2011). Pathogenicity tests were conducted twice using two A. gallica isolates (15389-1 and 15389-2) by inoculating sterile, 1-month old, rooted tissue-cultured cannabis plants of 'Wedding Cake' with 7.5 ml of homogenized A. gallica liquid inoculum (Baumgartner et al., 2010), added aseptically to the surface of the vermiculite, near the plant stem (Ford et al., 2017). Eight plants were inoculated and two (using sterile water instead of inoculum) were used as negative controls. Plants were incubated at 21-26 °C under 40 to 80 μmol·m-2·s-1 from full spectrum light source with an 18/6 photoperiod to support vegetative growth. Plants were watered with 25 ml sterile nutrient solution (Cutting Edge Solutions, Santa Rosa, CA, U.S.A.) at 1 to 2-week intervals, according to the plant's need. At eight weeks post inoculation, all eight inoculated plants showed symptoms of yellowing and wilting. Uptake of the nutrient solution and water had also stopped by this time. The two non-inoculated plants, however, remained healthy throughout the 8-week period (Supplementary Fig 1B). At the end of the experiment, samples were taken aseptically from the crowns and roots of each plant and plated on water agar amended with streptomycin (100 μg/ml) and benomyl (4 μg/ml). Hyphae were subcultured to 0.5X PDA to confirm species identity through ITS and TEF1a. A. gallica was reisolated from affected crowns and stems. This is the first report of A. gallica causing root and crown rot of C. sativa. Considering the expanding cultivation area of Cannabis crops due to legalization of the industry in many U.S. states, A. gallica root and crown rot may become a serious issue affecting the industry, even for plants maintained in non-woven polypropylene containers in direct contact with soil.

Bat Use of Hollows in California's Old-Growth Redwood Forests: From DNA to Ecology.

The loss of roosting resources, either through disturbance or removal, negatively affects bats. Identifying sensitive species and determining roost requirements are critical components in conserving their habitat. Cavity-roosting bats on the North Coast of California are known to use hollows in large redwood trees. In this study, we examined the factors determining the use of basal tree hollows by different bat species at eight redwood forest sites in Del Norte, Humboldt, and Mendocino Counties, California. Bat guano was collected from 179 basal hollow roosts from 2017 to 2018, and guano mass was used as an index of roosting activity. Nine bat species and one species group were identified by analysis of DNA in guano. We made a total of 253 identifications from 83 hollows into the 10 species categories. The most prevalent species were Myotis californicus (California myotis; 28.5% of all identifications), the Myotis evotis-Myotis thysanodes group (17.4%), Corynorhinus townsendii (17.0%), and Myotis volans (15.0%). We evaluated the extent to which habitat variables at the scales of the hollow, vicinity, and site influenced the level of roost use. The correlations between guano mass and habitat variables were examined using generalized additive mixed models. At the hollow scale, guano mass increased with ceiling height above the opening. At the vicinity scale, guano mass increased with less cover of small trees. At the site scale, there was no association between guano mass and distance to foraging areas, elevation, or the number of nearby hollows. These tree hollow roost preferences can inform land managers when planning the management and conservation of redwood forests.

A Reference Genome Assembly of the Bobcat, Lynx rufus.

The bobcat (Lynx rufus) is a medium-sized carnivore well adapted to various environments and an indicator species for landscape connectivity. It is one of the 4 species within the extant Lynx genus in the family Felidae. Because of its broad geographic distribution and central role in food webs, the bobcat is important for conservation. Here we present a high-quality de novo genome assembly of a male bobcat located in Mendocino County, CA, as part of the California Conservation Genomics Project (CCGP). The assembly was generated using the standard CCGP pipeline from a combination of Omni-C and HiFi technologies. The primary assembly comprises 76 scaffolds spanning 2.4 Gb, represented by a scaffold N50 of 142 Mb, a contig N50 of 66.2 Mb, and a BUSCO completeness score of 95.90%. The bobcat genome will be an important resource for the effective management and conservation of this species and comparative genomics exploration.

Identifying individual ungulates from fecal DNA: a comparison of field collection methods to maximize efficiency, ease, and success

Non-invasive genetic sampling can facilitate the identification of individual animals across a landscape, with applications to management and conservation. Fecal material is a readily available source of DNA, and various methods exist for collecting fecal samples for DNA preservation. In particular, swab methods offer considerable promise, but their utility in real-world field contexts remains relatively untested. We systematically compared multiple genetic fecal sampling methods across all stages of data collection and analysis, including sampling in the field, DNA extraction in the lab, and identification of individuals using microsatellite genotyping. We collected 112 fecal samples from black-tailed deer (Odocoileus hemionus columbianus) in the field in Mendocino County, California, across a range of sample conditions of unknown age. We systematically compared the efficiency, ease, and genotyping success of three methods for field collection and storage of ungulate fecal samples: whole pellets in ethanol, whole dry pellets in paper envelopes, and cotton swabs in buffer. Storage method, sample condition, and their interaction predicted genotyping success in the top binomial GLMMs. We found that swabbing pellets resulted in the greatest percentage of individually identifiable genotypes (81%, compared to 60% for dry samples and 56% for ethanol), despite lower DNA concentrations. While swabbing pellets requires a greater time investment in the field, the samples are easier and safer to store and transport, and subsequent labwork is more efficient as compared to whole-pellet collection methods. We, therefore, recommend the swab method for most contexts. We provide additional recommendations and field protocols based on subsequent collection of 2284 swab samples for a larger monitoring study of the deer population, given that this large number of samples spanned a range of sample conditions and time spent in storage.

Anaphylactic Reactions Due to Triatoma protracta (Hemiptera, Reduviidae, Triatominae) and Invasion into a Home in Northern California, USA.

Simple SummaryKissing bugs are bloodsucking insects found throughout the Western Hemisphere, including the United States, but also within certain regions of the Western Pacific, India, the Middle East, and Africa. Within the Americas, these insects are known to harbor a parasite known as Trypanosoma cruzi, the causative agent of an infection in humans and other mammals known as Chagas disease. The infection can be spread through the fecal matter of the kissing bug when exposed to the skin or ingested from contaminated food or drink products. Kissing bugs will invade human homes and bite residents and their pets. The bite from a kissing bug can also lead to serious allergic reactions, including anaphylaxis. A potentially life-threatening allergic response typically needs emergency medical attention. We describe a home that was invaded by kissing bugs in northern California where the resident developed serious allergic reactions to the bite. The kissing bugs were identified and a blood meal investigation found the presence of human blood as well as the parasite, Trypanosoma cruzi. The resident was tested extensively for chronic Chagas disease due to his repeated exposure to the kissing bug but was found to not have the disease. Those who live in regions where kissing bugs are found naturally should be aware that their bites can be highly allergenic.Background: Triatoma protracta is a triatomine found naturally throughout many regions of California and has been shown to invade human dwellings and bite residents. A man living in Mendocino County, California, reported developing anaphylactic reactions due to the bite of an “unusual bug”, which he had found in his home for several years. Methods: We conducted environmental, entomological, and clinical investigations to examine the risk for kissing bug invasion, presence of Trypanosoma cruzi, and concerns for Chagas disease at this human dwelling with triatomine invasion. Results: Home assessment revealed several risk factors for triatomine invasion, which includes pack rat infestation, above-ground wooden plank floor without a concrete foundation, canine living in the home, and lack of residual insecticide use. Triatomines were all identified as Triatoma protracta. Midgut molecular analysis of the collected triatomines revealed the detection of T. cruzi discrete typing unit I among one of the kissing bugs. Blood meal PCR-based analysis showed these triatomines had bitten humans, canine and unidentified snake species. The patient was tested for chronic Chagas disease utilizing rapid diagnostic testing and laboratory serological testing, and all were negative. Conclusions: Triatoma protracta is known to invade human dwellings in the western portions of the United States. This is the first report of T. cruzi-infected triatomines invading homes in Mendocino County, California. Triatoma protracta is a known vector responsible for autochthonous Chagas disease within the United States, and their bites can also trigger serious systemic allergic reactions, such as anaphylaxis.

Contrasting patterns of risk from human and non-human predators shape temporal activity of prey.

Spatiotemporal variation in predation risk arises from interactions between landscape heterogeneity, predator densities and predator hunting mode, generating landscapes of fear for prey species that can have important effects on prey behaviour and ecosystem dynamics. As widespread apex predators, humans present a significant source of risk for hunted animal populations. Spatiotemporal patterns of risk from hunters can overlap or contrast with patterns of risk from other predators. Human infrastructure can also reshape spatial patterns of risk by facilitating or impeding hunter or predator movement, or deterring predators that are themselves wary of humans. We examined how anthropogenic and natural landscape features interact with hunting modes of rifle hunters and mountain lions Puma concolor to generate spatiotemporal patterns of risk for their primary prey. We explored the implications of human-modified landscapes of fear for Columbian black-tailed deer Odocoileus hemionus columbianus in Mendocino County, California. We used historical harvest records, hunter GPS trackers and camera trap records of mountain lions to model patterns of risk for deer. We then used camera traps to examine deer spatial and temporal activity patterns in response to this variation in risk. Hunters and mountain lions exhibited distinct, contrasting patterns of spatiotemporal activity. Risk from rifle hunters, who rely on long lines of sight, was highest in open grasslands and near roads and was confined to the daytime. Risk from mountain lions, an ambush predator, was highest in dense shrubland habitat, farther from developed areas, and during the night and crepuscular periods. Areas of human settlement provided a refuge from both hunters and mountain lions. We found no evidence that deer avoided risk in space at the scale of our observations, but deer adjusted their temporal activity patterns to reduce the risk of encounters with humans and mountain lions in areas of higher risk. Our study demonstrates that interactions between human infrastructure, habitat cover and predator hunting mode can result in distinct spatial patterns of predation risk from hunters and other predators that may lead to trade-offs for prey species. However, distinct diel activity patterns of predators may create vacant hunting domains that reduce costly trade-offs for prey. Our study highlights the importance of temporal partitioning as a mechanism of predation risk avoidance.

Integration of grazing and herbicide application improves management of barb goatgrass and medusahead in pasture and rangelands

The invasive annual grasses barb goatgrass (Aegilops triuncialis L.) and medusahead (Elymus caput-medusae L.) are widespread in western states and present management challenges on grasslands. To develop an integrated management strategy for these species, we treated sites in five pastures in Mendocino County, comparing combinations of intensive sheep grazing, glyphosate herbicide (low and high), and application timings (tillering, boot and heading stage). We found that grazing alone reduced barb goatgrass spikelet densities by 68% and the number of seeds per spikelet by 35%. Both rates of glyphosate application without grazing had similar effects on seed production. High and low glyphosate application at tillering resulted in almost complete control of both target species. Boot- and heading-stage applications reduced barb goatgrass density by 39% and 32%, respectively. Application at the boot stage also resulted in an 82% reduction in number of seeds per barb goatgrass spikelet. Our results suggest that intensive grazing may be a useful management strategy to reduce barb goatgrass and medusahead spikelet densities and barb goatgrass seed numbers, especially when integrated with a boot- or heading-stage glyphosate application.

Controls on soil microbial carbon use efficiency over long-term ecosystem development

Carbon use efficiency—the proportion of substrate carbon that is converted to microbial biomass—is an important control on many ecosystem properties including carbon sequestration and nutrient cycling. Although CUE varies widely across terrestrial ecosystems, a coherent understanding of edaphic controls on CUE is lacking, thereby limiting the accuracy of global carbon models. The objective of this study was to determine how microbial CUE changes with long-term soil development and nutrient availability. Soil was collected across the chronosequence and fertility gradient at Jug Handle State Natural Reserve (the “Ecological Staircase”) in Mendocino County, CA. These soils exhibit a range in pH (3.29–6.59), litter quantity and quality (litter C:N, 32–70), and clay content (14.13–87.30%), while other factors such as modern-day climate, potential biota, and parent material are common to all sites. CUE varied significantly with soil and ecosystem development; the relationship was unimodal over geological time with CUE peaking at intermediate aged soils. Soil organic matter (SOM) content and pH were the most important variables each accounting for 30% of the variation in CUE across sites. Soil pH had a quadratic relationship with CUE, peaking at pH 4.7. Litter carbon to phosphorus (C:P) and nitrogen to phosphorus (N:P) ratios were also significant factors (Pearson’s r = 0.57 and 0.39 respectively). These results demonstrate that CUE changes in complex ways with soil fertility and long-term ecosystem development, and that edaphic factors such as SOM, pH, and litter quality need to be taken into account when predicting CUE for a given system.

Allocybaeina littlewalteri (Araneae: Cybaeidae): a new genus and species endemic to northwestern California.

Various undescribed Cybaeina Chamberlin Ivie (Araneae: Dictynoidea: Cybaeidae) and Cybaeina-like taxa are known from forested habitats in the west coast of North America. Most have very restricted ranges within the northern portion of the Californian Floristic Province, a well-known biodiversity hotspot. Here we describe Allocybaeina Bennett gen. nov. and its single included species, Allocybaeina littlewalteri Bennett spec. nov. This infrequently collected species is restricted to forested habitat in a small area of the coastal watersheds of southern Humboldt and western Mendocino Counties in northwestern California, U.S.A. In addition to descriptions we provide diagnoses, illustrations, a distribution map, and discuss conservation implications for this distinctive new genus and species.

Borrelia burgdorferi and Anaplasma phagocytophilum Genospecies in Northern California.

The sensu lato (s.l.) complexes of Borrelia burgdorferi and Anaplasma phagocytophilum include pathogenic genospecies each with distinct ecologies in northern California, yet, most work conflates the genospecies of each pathogen into one sensu lato species. Detailed understanding of the differences in geographic distributions and ecology among genospecies is lacking. We aimed to evaluate whether two B. burgdorferi and two A. phagocytophilum genospecies in high-risk locations in coastal northern California were spatially clustered and if presence of a particular genospecies was associated with geographical site, host species, or other demographic or ecological variables. DNA sequencing was performed to differentiate genospecies of Borreliae and Anaplasma from PCR-positive dusky-footed woodrats (Neotoma fuscipes) and sciurids (chipmunks, Tamias spp., and Douglas squirrels, Tamiasciurus douglasii) at four sites in northwestern California. Logistic regression was performed to assess associations of genospecies with the predictor variables host species, host sex, site, season, and year. Spatial clustering was assessed using a Poisson spatial scan statistic in SaTScan. Host species was a significant predictor for Borrelia bissettiae, B. burgdorferi sensu stricto (s.s.), A. phagocytophilum s.s., and the DU1 Anaplasma genospecies. Woodrats were significantly more likely to be PCR-positive for B. bissettiae and A. phagocytophilum DU1 genospecies, while A. phagocytophilum s.s. and B. burgdorferi s.s. were significantly associated with sciurids. We report a single Borrelia lanei in an Allen's chipmunk (Tamias senex) from the Hoopa Valley Tribal Reservation. A significant spatial cluster of A. phagocytophilum s.s. was detected at Hendy Woods State Park in Mendocino County. These results highlight the need to better understand genospecies partitioning according to host species to further assess human risks, aid in future surveillance, and inform targeted research.

Cost Effectiveness of Livestock Guardian Dogs for Predator Control

ABSTRACTPredation threatens the economic viability of sheep operations in the United States. Many producers recognize the need to complement lethal control methods with nonlethal strategies such as the use of livestock guardian dogs (LGDs), but little information exists on benefits and costs. We report on a comprehensive benefit–cost analysis of the decision to incorporate LGDs onto a sheep operation in Mendocino County, California, USA, based on data collected during 2013–2017, where livestock predation by coyotes (Canis latrans) has been a persistent problem. We estimated that for a representative sheep operation with a breeding flock of 500 adult females (ewes), the use of 5 LGDs reduced lambs and ewes lost to coyote predation by 43% and 25%, respectively, for a total savings of US$16,200 over 7 years. However, we found that costs, which included acquisition and maintenance expenses, exceed benefits of this investment over the 7‐year useful life of LGDs by US$13,413. Our results inform the adoption of LGDs, demonstrating that LGDs are only cost‐effective for certain types of operations, namely those where LGDs are able to achieve high rates of predator protection efficacy. © 2020 The Wildlife Society.

OCCURRENCE OF A SUITE OF STREAM-OBLIGATE AMPHIBIANS IN TIMBERLANDS OF MENDOCINO COUNTY, CALIFORNIA, EXAMINED USING ENVIRONMENTAL DNA

Stream-obligate amphibians are important indicators of ecosystem health in the Pacific Northwest, but distributional information to improve forest management is lacking in many regions. We analyzed archived DNA extracted from water samples in 60 pools in streams on private timberlands in Mendocino County, California, for 3 California Species of Special Concern—Coastal Tailed Frogs (Ascaphus truei), Foothill Yellow-legged Frogs (Rana boylii), and Southern Torrent Salamanders (Rhyacotriton variegatus)—to better understand their distributions in the region. Detection probabilities for eDNA of Foothill Yellow-legged Frogs and Coastal Tailed Frogs were positively influenced by water temperature. eDNA occurrence for both frogs was affected by whether silt or organic matter was a dominant substrate in the sampled pool, and Foothill Yellow-legged Frog eDNA occurrence was also affected by water temperature. Foothill Yellow-legged Frog eDNA occurrence had a strong, positive association with water temperature, with occurrence unlikely below 14°C and very likely above 16°C, and a positive association with silt or organic substrates in pools, which was likely an indicator of higher-order stream reaches. In contrast, Coastal Tailed Frogs had a negative association with silt or organic substrates. Historical visual detections were generally congruent with findings using eDNA, but differences highlight important areas for further study. We did not detect Southern Torrent Salamanders using eDNA at any sites. Our study reinforces that ecological relationships of these species are varied, and shows the importance of maintaining the integrity of streams with diverse characteristics for conserving stream amphibians.

POINT ARENA MOUNTAIN BEAVER (APLODONTIA RUFA NIGRA) SELECTS COOL CLIMATES AT FINE SPATIAL SCALES

Climatically sensitive species are naturally expected to experience disproportionate impacts from climate change. Although many vertebrates select microhabitats that allow them to persist toward the edge of their physiological limits, climate-driven models are often conducted at spatial scales too coarse to capture these fine-scale behaviors. One such climatically limited species is the monotypic Mountain Beaver (Aplodontia rufa), a species endemic to western North America. Mountain Beavers have physiological constraints that limit their distribution to cool, moist habitats. Although they have persisted through past periods of climate change, increasing temperature since the last glacial maximum is believed to have had a strong influence in reducing their range. This is particularly true for the federally endangered Point Arena subspecies of Mountain Beaver (Aplodontia rufa nigra; hereafter PAMB), found toward the southwestern edge of their range in Mendocino County on the coast of California. Previous efforts to model PAMB habitat suitability were conducted at the landscape scale. However, as a climatically sensitive taxon with limited mobility, it is important to understand the influence of microclimates on habitat suitability, particularly in the context of global climate change. We created downscaled climate data that we combined with known locations of PAMB to create a fine-scale species distribution model. Mean temperature was the strongest predictor of PAMB presence, with an increased probability of presence at lower mean temperatures. Although PAMB may be living at the edge of their physiological limits, they appear to be selecting habitat at a microclimate scale similar to elsewhere in their range, which allows them to persist at this margin. Conservation efforts for PAMB should prioritize habitat restoration, as well as maintaining and increasing connectivity between microrefugia, to provide cooler areas for PAMB persistence.

“We can't just be a county that supports inebriants”: Voices of the noncannabis agricultural community

Legalized recreational cannabis poses uncertainty and challenges for the noncannabis agricultural and ranching community in Northern California, including what it might mean in terms of the price of farmland and ranchland and the effects on the regional culture of diverse crop production. In-depth interviews in Humboldt, Mendocino and Sonoma counties with noncannabis farmers, ranchers and key individuals closely tied to the community revealed insight and an overarching concern about the future for noncannabis producers in those counties. The research was conducted in the summer and fall of 2017, when the state and counties were ramping up development and implementation of recreational cannabis cultivation policies. Interviewees expressed concern about land prices, potential crop shifts, and outside investment in the cannabis sector, and recognized the parallels and emerging alliances between wine and cannabis producers. They also identified opportunities for diversifying their production and for improving the environmental impacts of cannabis production.

<p class="HeadingRunIn"><strong>A new species of <em>Buccinum</em> from California (Gastropoda: Buccinidae)</strong></p>

Buccinum macleani n. sp., from off Fort Bragg, Mendocino County, California, is described. The new species is placed tentatively in the genus Buccinum (s.l.), based on radular characteristisc and shell morphology. It differs from all other eastern Pacific Buccinum by its very compressed profile.