Central California Research Articles

The Dolan Fire of Central Coastal California: Burn Severity Estimates from Remote Sensing and Associations with Environmental Factors

In 2020, wildfires scarred over 4,000,000 hectares in the western United States, devastating urban populations and ecosystems alike. The significant impact that wildfires have on plants, animals, and human environments makes wildfire adaptation, management, and mitigation strategies a critical task. This study uses satellite imagery from Landsat to calculate burn severity and map the fire progression for the Dolan Fire of central Coastal California which occurred in August 2020. Several environmental factors, such as temperature, humidity, fuel type, topography, surface conditions, and wind velocity, are known to affect wildfire spread and burn severity. The aim of this study is the investigation of the relationship between these environmental factors, estimates of burn severity, and fire spread patterns. Burn severity is calculated and classified using the Difference in Normalized Burn Ratio (dNBR) before being displayed as a time series of maps. The Dolan Fire had a moderate severity burn with an average dNBR of 0.292. The ignition site location, when paired with the patterns of fire spread, is consistent with wind speed and direction data, suggesting fire movement to the southeast of the fire ignition site. Patterns of increased burn severity are compared with both topography (slope and aspect) and fuel type. Locations that were found to be more susceptible to high burn severity featured Long Needle Timber Litter and Mature Timber fuels, intermediate slope angles between 15 and 35°, and north- and east-facing slopes. This study has implications for the future predictive modeling of wildfires that may serve to develop wildfire mitigation strategies, manage climate change impacts, and protect human lives.

Untargeted serum metabolic profiling of diabetes mellitus among Parkinson’s disease patients

Type 2 diabetes mellitus (T2DM) is a common comorbidity among Parkinson’s disease (PD) patients. Yet, little is known about dysregulated pathways that are unique in PD patients with T2DM. We applied high-resolution metabolomic profiling in serum samples of 636 PD and 253 non-PD participants recruited from Central California. We conducted an initial discovery metabolome-wide association and pathway enrichment analysis. After adjusting for multiple testing, in positive (or negative) ion mode, 30 (25) metabolic features were associated with T2DM in both PD and non-PD participants, 162 (108) only in PD participants, and 32 (7) only in non-PD participants. Pathway enrichment analysis identified 17 enriched pathways associated with T2DM in both the PD and non-PD participants, 26 pathways only in PD participants, and 5 pathways only in non-PD participants. Several amino acid, nucleic acids, and fatty acid metabolisms were associated with T2DM only in the PD patient group suggesting a possible link between PD and T2DM.

Diet and the gut microbiome in patients with Parkinson’s disease

It has been suggested that gut microbiota influence Parkinson’s disease (PD) via the gut–brain axis. Here, we examine associations between diet and gut microbiome composition and its predicted functional pathways in patients with PD. We assessed gut microbiota in fecal samples from 85 PD patients in central California using 16S rRNA gene sequencing. Diet quality was assessed by calculating the Healthy Eating Index 2015 (HEI-2015) based on the Diet History Questionnaire II. We examined associations of diet quality, fiber, and added sugar intake with microbial diversity, composition, taxon abundance, and predicted metagenomic profiles, adjusting for age, sex, race/ethnicity, and sequencing platform. Higher HEI scores and fiber intake were associated with an increase in putative anti-inflammatory butyrate-producing bacteria, such as the genera Butyricicoccus and Coprococcus 1. Conversely, higher added sugar intake was associated with an increase in putative pro-inflammatory bacteria, such as the genera Klebsiella. Predictive metagenomics suggested that bacterial genes involved in the biosynthesis of lipopolysaccharide decreased with higher HEI scores, whereas a simultaneous decrease in genes involved in taurine degradation indicates less neuroinflammation. We found that a healthy diet, fiber, and added sugar intake affect the gut microbiome composition and its predicted metagenomic function in PD patients. This suggests that a healthy diet may support gut microbiome that has a positive influence on PD risk and progression.

Intra- and interannual variation in the foraging behavior of common Murres (Uria aalge) in the Central California current

Seabirds modify their behavior during the breeding season as they transition from incubation (self-feeding) to chick-rearing (self-feeding + chick provisioning) periods, which affects parental foraging patterns and distribution. However, it is less clear how much flexibility parents have to modulate their behavior when environmental conditions are unusually poor. Using GPS loggers and time depth recorders, we examined the foraging flexibility of common murres (Uria aalge) at Southeast Farallon Island as adjustments were made between breeding phases and across consecutive years (2019 and 2020) with contrasting oceanographic conditions (i.e. prominent marine heatwave in 2019). Foraging trips were longer during the incubation period (2019: 31.7 ± 20.1 h; 2020: 23.5 ± 7.2 h) compared to the chick provisioning period (2019: 12.2 ± 9.9 h; 2020: 7.5 ± 8.3 h). Moreover, parents generally ventured farther from the colony during incubation (2019: 34.7 ± 17.6 km; 2020: 30.1 ± 11.5 km) than when foraging to provision chicks (2019: 22.6 ± 17.1 km; 2020: 14.1 ± 15.0 km) in each year. Nevertheless, overall foraging ranges had a high degree of overlap (> 60%) within breeding phases and across years, suggesting that murres at this colony are constrained by the habitats primarily based on foraging range. Murres dove deeper during incubation compared to chick-rearing in 2020 (36.0 ± 24.4 vs 19.5 ± 15.2 m), but there were no other differences within or across years in diving behavior, suggesting that diving effort was less affected by breeding stage. Interannual differences in foraging behavior only occurred during chick-feeding trips and were likely driven by the prey species present. For example, rockfish were more common in chick diets in 2020, when ocean temperatures were cooler compared to 2019. Despite similarities in trip parameters between years, breeding productivity was much lower in 2019 compared to both long-term averages and the 2020 season, suggesting a potential constraint on murre behavioral flexibility when oceanographic variation occurs. These results emphasize the importance of examining behavior on multiple time scales to gain a better understanding of how predators respond to changes in their environment.

Plant networks are more connected by invasive brome and native shrub facilitation in Central California drylands

Dominant vegetation in many ecosystems is an integral component of structure and habitat. In many drylands, native shrubs function as foundation species that benefit other plants and animals. However, invasive exotic plant species can comprise a significant proportion of the vegetation. In Central California drylands, the facilitative shrub Ephedra californica and the invasive Bromus rubens are widely dispersed and common. Using comprehensive survey data structured by shrub and open gaps for the region, we compared network structure with and without this native shrub canopy and with and without the invasive brome. The presence of the invasive brome profoundly shifted the network measure of centrality in the microsites structured by a shrub canopy (centrality scores increased from 4.3 under shrubs without brome to 6.3, i.e. a relative increase of 42%). This strongly suggests that plant species such as brome can undermine the positive and stabilizing effects of native foundation plant species provided by shrubs in drylands by changing the frequency that the remaining species connect to one another. The net proportion of positive and negative associations was consistent across all microsites (approximately 50% with a total of 14% non-random co-occurrences on average) suggesting that these plant-plant networks are rewired but not more negative. Maintaining resilience in biodiversity thus needs to capitalize on protecting native shrubs whilst also controlling invasive grass species particularly when associated with shrubs.

Variability in coastal habitat available for Longfin Smelt Spirinchus thaleichthys in the northeastern Pacific Ocean

An understanding of oceanographic conditions and processes important to marine animal ecology is fundamental to the development of effective management and conservation actions. Longfin Smelt (Spirinchus thaleichthys) is a pelagic forage fish found in coastal and estuarine waters along the Pacific coast of North America from Alaska to central California. Substantial population declines in California’s San Francisco Estuary, where Longfin Smelt are protected under California’s Endangered Species Act, have prompted extensive study of estuarine factors associated with the decline. However, coastal factors that affect up to two-thirds of the Longfin Smelt life cycle are poorly understood and may be important drivers of population dynamics. We compiled coastal observations from numerous sources to estimate the range-wide coastal marine distribution of Longfin Smelt and assess habitat factors affecting distribution in the northeast Pacific Ocean. Based on maximum entropy species distribution models, Longfin Smelt distribution was correlated with depth, distance from the nearest estuary, sea surface temperature, and sea surface chlorophyll. Longfin Smelt were found in shallow, higher productivity coastal waters closer to estuaries, with depth and temperature the most consistent factors influencing distribution. Habitat suitability was highly variable at the southern extent of the range, particularly off the California coast, and was largely driven by habitat contractions associated with warm-water conditions. Study results provide insights into the habitat and range-wide distribution of an at-risk estuarine-reliant forage fish and are the first step toward identifying processes that affect the marine portion of the Longfin Smelt life cycle.

A Novel Hazard for an Endangered Fox in a Novel Environment.

Animals colonizing novel environments can encounter novel hazards. Endangered San Joaquin kit foxes (Vulpes macrotis mutica) are found in the cities of Bakersfield and Taft in central California, USA. We documented 66 incidents of kit foxes becoming entangled in sports netting (e.g., soccer nets, batting-cage nets) occurring from the 1980s through 2022. Overall, 25 of the foxes died. Adults were more likely to get entangled in soccer nets, whereas pups (<1 yr) were more likely to get entangled in batting-cage nets. Pups are more likely to die while entangled, probably due to smaller body mass and lower energy reserves. The reasons that kit foxes get entangled in netting were unclear, although incidents involving batting-cage netting and pups may be due to natal dens being located under or near batting cages. At current rates, this hazard is unlikely to limit urban kit fox populations. However, losses of this endangered species should be minimized and the incidents are easily mitigated by dropping or lifting nets when not in use.

Diverse habitats shape the movement ecology of a top marine predator, the white shark Carcharodon carcharias

AbstractAn animal's movement is influenced by a plethora of internal and external factors, leading to individual‐ and habitat‐specific movement characteristics. This plasticity is thought to allow individuals to exploit diverse environments efficiently. We tested whether the movement characteristics of white sharks Carcharodon carcharias differ across ontogeny and among habitats along the coast of Central California. In doing so, we elucidate how changes in internal state (physiological changes coinciding with body size) and external environments (differing seascapes and/or diel phases) shape the movement of this globally distributed predator. Twenty‐one white sharks, from small juveniles to large adults, were equipped with motion‐sensitive biologging tags at four contrasting seascapes: two islands, a headland, and an inshore cove. From multisensor biologging data, 20 metrics characterizing movement (i.e., depth use, vertical velocities, activity, turning rates, and bursting events) were derived and subjected to multivariate analyses. Movement characteristics were most different across seascapes, followed by ontogeny and diel phase. Juvenile sharks, which were only encountered at the cove, displayed the most distinct movement characteristics. Sharks at this seascape remained close to the shore traveling over smaller areas, shallower depth ranges, and with lower levels of tail beat frequencies, when corrected for size, than sub‐adult and adult sharks tagged elsewhere. Distinct tortuous daytime versus linear nighttime horizontal movements were recorded from sharks at island seascapes but not from those at the headland or inshore cove. At the offshore islands, the linear nighttime swimming patterns coincided with repeated dives to and from deeper water. The availability of prey and access to deeper water are likely drivers of the differences in movement characteristics described, with varying demographics of pinniped prey found at the subadult and adult aggregation areas and juvenile sharks being piscivorous and their habitat neither adjacent to pinniped haul out areas nor deeper water. This study demonstrates plasticity in the movements of a top predator, which adapts its routine to suit the habitat it forages within.

“Like Being in Purgatory”: Cultural Identity Mapping Centers Hmong American Experiences of Biculturalism

This study examines what it means to be bicultural to Hmong American emerging adults living in central California. Twenty-four participants ( Mage = 21.92 years) constructed a cultural identity map that portrayed what it means to them to be “Hmong American,” described both their cultural identity map content and their process of constructing it, and completed the Multigroup Ethnic Identity Measure (MEIM). Grounded theory analysis of cultural identity maps and accompanying conversations reveals the pervasiveness of bifurcated biculturalism, or the experience of having split selves. For participants in this study, perceived cultural incompatibility between Hmong and American cultures rendered it necessary to possess two (and sometimes more) distinct cultural identities, and required—for some, almost constant—frame-switching to manage these identities. This article offers an in-depth portrait of three illustrative cases, which represent diversity in terms of gender, social class, and MEIM score. Altogether, findings contribute to scientific understanding of the complex and contradictory nature of biculturalism for Hmong American emerging adults, and speak to the link between ethnic stereotypes and bicultural identity development. Methodologically, this study highlights the utility of identity mapping to examine psychological experiences of biculturalism and other aspects of identity about which people may have hidden, complex, and potentially contradictory stances.

Dispersal pathways of European green crab larvae into and throughout the eastern Salish Sea

The invasive European green crab (Carcinus maenas) was first detected on the US west coast around 1989 and has expanded its range northward from central California to southern Alaska. The eastern Salish Sea was initially thought to be protected from invasion by the dominant seaward surface current in the Strait of Juan de Fuca (SJdF). However, this “oceanographic barrier” has been breached as established green crab populations have been detected in the eastern Salish Sea in recent years. Here we carried out particle-tracking simulations to understand possible natural pathways of green crab larvae invading the eastern Salish Sea. Both diel vertical migration and temperature-dependent mortality were considered in these simulations. Our results suggest that green crab larvae from the outer coast (outside the Salish Sea) and Sooke Basin (in SJdF) could be carried into the eastern Salish Sea in a narrow time window during the later cold season (esp. in March) when frequent flow reversals in SJdF occur and the seasonally rising water temperature becomes relatively favorable for green crab larvae. The major pathway for larvae to reach the eastern Salish Sea is along the southern coast of SJdF. The probability of live larvae reaching the eastern Salish Sea is highly sensitive to water temperature. Sensitivity simulations indicate that a temperature increase of 0.5–1 °C would double or quadruple the probability of successful arrival in the eastern Salish Sea. This suggests that invading green crabs might have taken advantage of the mild winter conditions in recent warm years. Our results also suggest that the warming climate in the near future may facilitate green crab larval exchange across the Salish Sea.

Programmable flow injection: a versatile technique for benchtop and autonomous analysis of phosphate and silicate in seawater

High-resolution, autonomous monitoring of phosphate and silicate in the marine environment is essential to understand their complex dynamics and implications for the functioning of marine ecosystems. In the absence of dependable reagent-less sensors for these nutrients, leveraging established colorimetric techniques using miniaturized analyzers, such as programmable Flow Injection (pFI), offers the best immediate solution to meet oceanographic accuracy and precision standards. In this work, we further optimize the phosphomolybdate and silicomolybdate assays recently adapted for use with pFI, laying the groundwork for the technique’s use for long-term, autonomous operations. For both assays, we show that only a narrow range of acidities and molybdate concentrations can maximize sensitivity while minimizing salt effects. In addition, we demonstrate the stability of our optimized colorimetric reagent formulations, ensuring that analytical sensitivity remains within 10% of initial levels for at least 35 days of continuous use. We then applied our optimized protocols to produce oceanographically consistent phosphate and silicate profiles at the Hawaii Ocean Time Series (HOTS) and Southern Ocean Time Series (SOTS), respectively, which compared favorably against a reference method and historical data. Using certified reference materials for nutrients in seawater, we show that our pFI protocols, optimized for long-term operations, achieve a shipboard precision better than 6% and a relative combined uncertainty (k=1) of 4.5% for phosphate (0.45 - 2.95 µmol L-1) and 6.2% for silicate (2.2 to 103 µmol L-1). To demonstrate pFI’s potential as a versatile tool for autonomous monitoring, we report a five-day hourly phosphate time series at a coastal shore station in central California (n=121 analyses), examine phosphate uptake by seaweed at five-minute intervals at a seaweed aquaculture facility (n=103), and discuss a unique, high-resolution surface silicate transect spanning multiple frontal zones in the Australian sector of the Southern Ocean (n=249). These data, obtained using a commercially available pFI analyzer, confirm that pFI is a viable technology for autonomous monitoring of phosphate and silicate, paving the way for more ambitious, long-term deployments in a variety of settings.

Compound marine cold spells and hypoxic events in a nearshore upwelling system

Prolonged periods of extreme warm and cold seawater temperature anomalies, known as marine heatwaves (MHWs) and marine cold spells (MCSs), respectively, can have significant impacts on coastal marine ecosystems. Prior research has examined the co-occurrence of multiple extremes [low dissolved oxygen (DO) and/or low pH] during MHWs, with the impact of these compound events potentially exceeding that of a single stressor due to synergistic effects. However, we are not aware of any studies that have examined compound extreme events during MCSs, despite the ecosystem implications. Along Eastern Boundary Current Upwelling Systems (EBUS), strong-wind driven upwelling has led to reduced warming trends and persistence of MCSs, as well as an increased seasonal risk for coastal hypoxia via the cross-shelf advection of cold, low DO subthermocline waters. In this short communication, we investigated for the first time compound MCS-hypoxic events at a nearshore site in central California using several decades of nearshore water temperature data, short-term nearshore DO data, and several decades of DO data from the California Cooperative Oceanic Fisheries Investigations program. From 1988 to 2020, we identified 55 MCS events, with 50 events (∼90.9%) initiated during anomalously strong upwelling. Using long-term temperature-DO relationships, we identified 20 of the 55 MCS events (∼34.6%) as potential compound MCS-hypoxic events, with an average duration of 11.7 days. These compound events occurred almost exclusively during the major upwelling season (March to June) when there is a high propensity for the advection of cold, low DO subthermocline waters from the adjacent shelf into the nearshore. This work provides the first known investigation into the co-occurrence of MCS and hypoxic events in a nearshore upwelling system and provides a baseline for assessing future changes to these compound events in a changing climate, with important implications for ecosystem health in EBUS globally.

Participation in collaborative fisheries research improves the perceptions of recreational anglers towards marine protected areas

Collaborative fisheries research programs engage stakeholders in data collection efforts, often with the benefit of increasing transparency about the status and management of natural resources. These programs are particularly important in marine systems, where management of recreational and commercial fisheries have historically been contentious. One such program is the California Collaborative Fisheries Research Program (CCFRP), which was designed in 2006 to engage recreational anglers in the scientific process and evaluate the efficacy of California’s network of marine protected areas. CCFRP began on the Central Coast of California and expanded statewide in 2017 to include six partner institutions in three regions: Northern, Central, and Southern California. To date, over 2,000 volunteer anglers have participated in the program, with many anglers volunteering for multiple years. However, the impacts of outreach, education, and collaborative research on those anglers at the statewide scale are currently unknown. Thus, the objective of the current study was to survey the statewide pool of volunteer anglers to assess the degree to which participation in CCFRP has influenced angler perceptions of MPAs, fisheries management, and conservation. We received 259 completed surveys out of a pool of 1,386 active anglers, equating to an 18.7% response rate. Participation in CCFRP resulted in a significant, positive impact on anglers’ attitudes towards MPAs in California across all regions. Anglers who participated in six or more CCFRP fishing trips had a more positive perception of MPAs than those who participated in fewer trips. Volunteer anglers across all regions perceived that they caught larger fishes, a higher abundance of fishes, and a greater diversity of species inside MPAs, consistent with the ecological findings of the program. These results highlight the benefits of involving community members in collaborative scientific research. Collaboration between researchers and the broader community increases transparency and trust between stakeholders, and results in greater understanding of natural resource dynamics, ultimately producing better management outcomes.

Biological and Physical Controls on Multidecadal Acidification in a Eutrophic Estuary

AbstractEstuaries support ecologically and economically important resources that are vulnerable to ocean acidification from rising anthropogenic CO2. However, complex local processes in estuaries complicate and may disguise long‐term pH trends. For example, terrestrial nutrient runoff and coastal upwelling may exacerbate pH variability and declines. We investigated eutrophication impacts on acidification in a central California estuary, Elkhorn Slough, which receives high nutrient loads from intensive surrounding agriculture and upwelling of the California Current System. We examined drivers of acidification including nutrients, ecosystem metabolism, and upwelling by modeling pH trends over 20 years using a Generalized Additive Mixed Model at four sites from the National Estuarine Research Reserve Systemwide Monitoring Program and collected additional water samples to calculate aragonite saturation. Our models revealed acidification trends over two decades which were more pronounced near the marine inlet. Near the marine inlet, high nutrient levels and lower buffering were associated with the greatest rate of acidification in the estuary, which was four times greater than the trend from anthropogenic CO2 alone. Compared to fully tidal sites, a tidally restricted site showed diminished pH declines over time because of higher mean pH and aragonite saturation levels, but greater diel and seasonal variability associated with cycles of ecosystem metabolism and tidal range. Therefore, short‐term drops of saturation are threats to acidity in this location. The effects of enhanced seasonal cycles or long‐term trends in different zones of the estuary have implications for monitoring estuaries with a temporal frequency and scale to capture coastal acidification risks.

Physical and Biogeochemical Properties of California Current Upwelled Source Waters

AbstractCoastal upwelling variability in the California Current region, one of the four main eastern boundary current upwelling systems, is controlled by processes acting over a wide range of spatial and temporal scales. While the ensuing ecosystem response depends strongly on upwelled water properties, determining their exact physical and biogeochemical characteristics is notoriously difficult as it requires tracking water masses backward in space and time from the moment they upwell near the coast to their subsurface origin. Adjoint model simulations have been used successfully to track water masses in coastal upwelling systems and the work presented here extends these applications to determining the co‐variability of physical and biogeochemical properties of source waters at spatial scales that resolve the known alongshore variability of coastal upwelling in the region. Notably, the results identify that the modulation of coastal upwelling efficiency by onshore/offshore geostrophic meanders is the dominant mechanism explaining alongshore variability in source depth and properties of upwelled waters. The simulations also reveal that source water properties vary seasonally in response to different balances between coastal upwelling intensity and biogeochemical processes. During spring, interannual variability of physical and biogeochemical properties is directly tied to the intensity of upwelling‐favorable alongshore winds, whereas, during summer, biogeochemical properties respond more strongly to biological activity and subsequent organic matter remineralization at depth. Overall, the present work provides important insight into the mechanisms responsible for the alongshore mosaic and seasonal variation of upwelled source water properties in the central California Current region.

Simulation of 0–7.5 Hz physics-based nonlinear ground motions for maximum credible earthquake scenarios at the Long Valley Dam, CA

We have conducted three-dimensional (3D) 0–7.5 Hz physics-based wave propagation simulations to model the seismic response of the Long Valley Dam (LVD), which has formed Lake Crowley in Central California, to estimate peak ground motions and settlement of the dam expected during maximum credible earthquake (MCE) scenarios on the nearby Hilton Creek Fault (HCF). We calibrated the velocity structure, anelastic attenuation model, and the overall elastic properties of the dam via linear simulations of a Mw 3.7 event as well as the Mw 6.2 Chalfant Valley earthquake of 1986, constrained by observed ground motions on and nearby the LVD. The Statewide California Earthquake Center (SCEC) Community Velocity Model CVM-S4.26.M01 superimposed with a geotechnical layer using [Formula: see text] information tapered from the surface to a 700-m depth was used in the simulations. We found optimal fit of simulated and observed ground motions at the LVD using frequency-independent attenuation of [Formula: see text] ([Formula: see text] in m/s). Using the calibrated model, we simulated 3D nonlinear ground motions at the LVD for Mw 6.6 rupture scenarios on the HCF using an Iwan-type, multi-yield-surface technique. We use a two-step method where the computationally expensive nonlinear calculations were carried out in a small domain with the plane wave excitation along the bottom boundary obtained from a full-domain 3D linear finite-fault simulation. Our nonlinear MCE simulation results show that peak ground velocities (PGVs) and peak ground accelerations (PGAs) as high as 72 cm/s and 0.55 g, respectively, can be expected at the crest of the LVD. Compared with linear ground motion simulation results, our results show that Iwan nonlinear damping reduces PGAs on the dam crest by up to a factor of 8 and increasingly depletes the high-frequency content of the waves toward the dam crest. We find horizontal relative displacements of the material inside the dam of up to [Formula: see text] and up to [Formula: see text] of vertical subsidence, equivalent to 1% of the dam height.

State of the California Current Ecosystem report in 2022: a tale of two La Niñas

2022 marked the third consecutive La Niña and extended the longest consecutive stretch of negative Oceanic Niño Index since 1998-2001. While physical and biological conditions in winter and spring largely adhered to prior La Niña conditions, summer and fall were very different. Similar to past La Niña events, in winter and spring coastal upwelling was either average or above average, temperature average or below average, salinity generally above average. In summer and fall, however, upwelling and temperature were generally average or slightly below average, salinity was close to average and chlorophyll a was close to average. Again, as during prior La Niña events, biomass of northern/southern copepods was above/below average off Oregon in winter, and body size of North Pacific krill in northern California was above average in winter. By contrast, later in the year the abundance of northern krill dropped off Oregon while southern copepods increased and body sizes of North Pacific krill fell in northern California. Off Oregon and Washington abundances of market squid and Pacific pompano (indicators of warm, non-typical La Niña conditions) were high. In the 20th century, Northern anchovy recruitment tended to be high during cold conditions, but despite mostly warm conditions from 2015-2021 anchovy populations boomed and remained high in 2022. Resident seabird reproductive success, which tended in the past to increase during productive La Niña conditions was highly variable throughout the system as common murre and pelagic cormorant, experienced complete reproductive failure at Yaquina Head, Oregon while Brandt’s cormorant reproduction was average. At three sampling locations off central California, however, common murre reproduction was close to or above average while both pelagic and Brandt’s cormorant were above average. California sealion reproduction has been above average each year since 2016, and pup weight was also above average in 2022, likely in response not to La Niña or El Niño but continuous high abundance of anchovy. The highly variable and often unpredictable physical and biological conditions in 2022 highlight a growing recognition of disconnects between basin-scale indices and local conditions in the CCE. “July-December 2022 is the biggest outlier from individual “strong” La Niña (events) ever going back to the 50s.” – Nate Mantua

Testing strategies to enhance transplant success under stressful conditions at a tidal marsh restoration project

Tidal marsh restoration is becoming an increasingly common tool to plan for future sea level rise. Subsided marshes' elevation can be restored through sediment additions, which may necessitate the reestablishment of vegetation. Understanding key actions to increase vegetation cover at areas that remain persistently bare following elevation restoration is a critical component of a project's long‐term success. Dominant species can shape ecosystem function, as well as ameliorate stressful environments. We transplanted the dominant species, Salicornia pacifica, into bare areas of a restored tidal marsh in central California, United States, 3 years following a sediment addition. We tested salt hardening of plants before transplanting, targeted irrigation, transplant size, and planting configuration to identify management actions that could help vegetation persist in the most stressful areas of the high marsh. Weekly targeted irrigation until the first rains began was critical for small plant survivorship. We found that larger plants had increased survivorship and contributed higher amounts of growth and cover but did not facilitate the performance of nearby smaller plants. After 2 years, we determined that using lone, larger plants was more cost‐effective than multiple smaller plants at our tidal marsh. However, performance was highly site‐specific with dramatically less growth at a drier site with sandier soil. Our results highlight the importance of identifying site‐specific restoration strategies that either ameliorate or help plants tolerate stressful conditions, contributing to the continued success of tidal marsh restoration for climate resilience.

Agricultural paraquat dichloride use and Parkinson's disease in California's Central Valley.

Paraquat dichloride is currently among the most widely used commercial herbicides in the USA. In the present study, we provide epidemiological assessment of ambient paraquat exposure and Parkinson's disease (PD) risk in a population-based study of PD in agricultural regions of Central California. Based on 829 PD patients and 824 community controls, we assessed associations between ambient paraquat dichloride exposure and PD. We estimated residential and workplace proximity to commercial agricultural applications in three California counties since 1974 using the CA pesticide use reporting (PUR) data and land use maps. We evaluated any, duration and average intensity [pounds (0.45 kilograms) per acre per year] of exposure for paraquat in four time windows. Ambient paraquat exposure assessed at both residence and workplace was associated with PD, based on several different exposure measures. The PD patients both lived and worked near agricultural facilities applying greater amounts of the herbicide than community controls. For workplace proximity to commercial applications since 1974, working near paraquat applications every year in the window [odds ratio (OR) = 2.15, 95% confidence interval (CI) = 1.46, 3.19] and a higher average intensity of exposure [per 10 pounds (4.54 kilograms), OR = 2.08, 95% CI = 1.31, 3.38] were both associated with an increased odds of PD. Similar associations were observed for residential proximity (duration: OR = 1.91, 95% CI = 1.30, 2.83; average intensity: OR = 1.72, 95% CI = 0.99, 3.04). Risk estimates were comparable for men and women, and the strongest odds were observed for those diagnosed at ≤60 years of age. This study provides further indication that paraquat dichloride exposure increases the risk of Parkinson's disease.

Factors Associated with Condom Use among Community College Students

The incidence and prevalence of sexually transmitted infections (STIs) have increased over the past decade, with half of all new diagnoses occurring in young people ages 15-24 years. Despite the risk, college students report low rates of condom use during sex. This study investigated factors associated with condom use in college students with the intent to inform health education strategies. In this cross-sectional study, a 40-item survey was administered to a random sample of classes at a community college in Central California. A total of 883 students participated. A multivariate logistic regression model identified factors associated with condom use, controlling for demographics, knowledge, and perceptions about sexually transmitted infections (STIs) and condoms.Hispanic/Latino respondents had higher rates of condom use compared to non-Hispanic/Latinos, as did non-White respondents compared to White respondents, non-females, and individuals who were not in a relationship. Regression results revealed that assertive negotiation (i.e., directly requesting to use condoms) was the most significant influencer of condom use. STI knowledge was not associated with condom use, nor was perceived seriousness or susceptibility to STIs.While traditional health promotion programs focus on knowledge and access to condoms, these results suggest that additional factors influence condom use, including the ability to directly request condom use with partners. In addition to topics such as STIs, contraception, and pregnancy, comprehensive sexual health education should also include communication and negotiation strategies between partners, through a lens that includes all sexualities and gender identities.