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California (USA) is home to a diverse lamprey fauna that historically occupied streams throughout the state and into Baja California (México). Recent range fluctuations by anadromous Pacific Lamprey, Entosphenus tridentatus, in its southern range have caused concern with regard to anticipated climatic changes and warming of stream habitats. Examination of temperature tolerances in lampreys has generally been conducted in the laboratory. Here we associate modeled mean August water temperatures (AugTw) of stream reaches currently occupied by lampreys in California for periods 2002–2011, 2040, 2080, and + 3 °C scenarios. The nine lamprey taxa in California occupy a considerable range in temperatures, reflecting their broad elevational and latitudinal ranges, with 2002–2011 AugTw of 7.9–25.9 °C. This includes the current distribution of the anadromous Pacific Lamprey (10.3–25.9 °C). Under a projected relatively extreme + 3 °C increase, only eight streams state-wide are projected to have reaches exceeding AugTw of 28.0 °C, accounting for 2.6% of currently occupied habitat. Actual 2021 August water temperatures surveyed at selected sites with high modeled 2002–2011 temperatures and currently occupied by Pacific Lamprey ranged from 18.5 to 32.6 °C (mean, 27.9 °C). Projected temperature increases suggest that future conditions may be within the range currently encountered and tolerated by Pacific Lamprey. Empirical observations of multiple-year classes of ammocoetes (lamprey larvae) in warmer stream reaches suggest that lampreys are successfully rearing in streams that reach temperatures close to the upper lethal limits suggested by laboratory studies. How they do this is not clear, but may involve both physiological tolerances and behavioral responses to high-temperature conditions. Our results also suggest that rising stream temperatures are not likely to restrict the distribution of western lampreys in the foreseeable future, and therefore, conservation strategies should focus on other issues, such as restoring access to historical habitats, avoiding stream desiccation, and restoring natural flow regimes. [ABSTRACT FROM AUTHOR]

We investigated the guidance efficiency of fish screens for the protection of emigrating Pacific LampreyEntosphenus tridentatusand Western River Lamprey (also known as River Lamprey)Lampetra ayresiiin a series of experimental trials. All trials were conducted at the Tracy Fish Collection Facility, located in the Sacramento–San Joaquin River Estuary at the entrance to one of the world’s largest surface water diversions. Using 1,200 lamprey macrophthalmia, we tested for the effect of screen type, time of day, and channel water velocity to guide their swimming behavior to avoid entrainment. We found overwhelming evidence for an effect of screen type on efficiency, whereby all lampreys were successfully guided to a holding tank when a vertical traveling screen was used. This was likely due to the small pore size of the screen relative to lamprey sizes. In contrast, the efficiency of louvers, a behavioral screen designed for salmonids, varied by the interaction of time of day and channel velocity. During nighttime, when lamprey typically emigrate, louver guidance efficiency ranged from 21% (95% CI, 14–30%) to 24% (95% CI, 16–34%). These results were applied to estimate the probability for salvage of lamprey macrophthalmia at the Tracy Fish Collection Facility, which includes a two-stage fish screen design. Between 1957 and 2014, we estimated that 94–96% of the lampreys that were entrained in the export flows were lost and not returned to the delta. However, the probability for fish loss was reduced in 2014 when the secondary louver was replaced with a vertical traveling screen. Our results suggest that lamprey macrophthalmia entrainment into the canals will be eliminated at the Tracy Fish Collection Facility if the primary screen is converted to vertical traveling screen. Surface water diversions may represent a substantial threat to regional metapopulations of anadromous lamprey species worldwide, and screening approaches applied to other fish species such as salmonids may not be protective of lampreys. Received June 7, 2016; accepted August 23, 2016Published online December 20, 2016 [ABSTRACT FROM AUTHOR]

The Modoc sucker received legal protection in the United States based partially on concerns that anthropogenic environmental changes had restricted migration among populations and catalyzed hybridization with a more abundant congener, the Sacramento sucker . We applied eight microsatellite markers to samples of both species collected from two tributaries to the Pit River, California (Ash Creek and Turner Creek), and one tributary of Goose Lake, Oregon (Thomas Creek). Modoc sucker populations in these three tributaries seemed to be largely isolated from one another: gene flow between Ash Creek and Turner Creek was no greater than that among these two creeks and Thomas Creek. In contrast, divergence estimates among collections of Sacramento suckers indicated greater gene flow between Ash Creek and Turner Creek than between either of these creeks and Thomas Creek. Samples collected at a single site (Ash Valley) were identified based on morphology as Modoc suckers, but genetic data suggested they were much more similar to Sacramento suckers. Interspecific hybrids were detected in all three tributaries. Collections of Modoc suckers yielded 0.0--3.9%% hybrids, and collections of Sacramento suckers yielded 0.0--80.0%% hybrids. The two collections with the greatest proportions of hybrids (54.5 and 80.0%%) were both from tributaries to lower Thomas Creek, and neither of these tributaries is thought to have upstream populations of Modoc suckers. Based on 1) low levels of hybrid detection in all three tributaries, 2) the absence of hybrids from typical parental habitats (upstream habitats for Modoc suckers and Pit River mainstem for Sacramento suckers), and 3) highly significant RST (variance in allele size) values between the species, we conclude that hybridization is common but that significant introgression (i.e., loss of parental genotypes) has not occurred. We also note that hybridization, and subsequent introgression, may become a conservation concern in such cases when the habitat of one or both of these species is eliminated or modified. [ABSTRACT FROM AUTHOR]

Presents the historical, political and empirical perspectives on Confluent Education, a program at the University of California, Santa Barbara (USCB). Description of Confluent Education; Details on the orientation to learning (OTL) instructional values; Contextual interpretation of what happened to the program.

Assesses the effects of a year's academic training of students of Master of arts degree (MA) in Counseling Psychology and Confluent Education in the University of California (Santa Barbara) using the variables Affective Bias and Personal Growth Orientation. Tendency of Confluent Education students to be more humanistic in their instructional values.

Species ranges that span different geographic landscapes frequently contain cryptic species- or population-level structure. Identifying these possible diversification factors can often be accomplished under a comparative phylogeographic framework. However, comparisons suffer if previous studies are limited to a particular group or habitat type. In California, a complex landscape has led to several phylogeographic breaks, primarily in terrestrial species. However, two sister taxa of freshwater fish, riffle sculpin (Cottus gulosus) and Pit sculpin (Cottus pitensis), display ranges based on morphological identifications that do not coincide with these breaks. Using a comprehensive sampling and nuclear, mitochondrial and microsatellite markers, we hypothesized that proposed species ranges are erroneous based on potential hybridization/gene flow between species. Results identified a phylogeographic signature consistent with this hypothesis, with breaks at the Coast Range Mountains and Sacramento/San Joaquin River confluence. Coastal locations of C. gulosus represent a unique lineage, and 'true' C. gulosus were limited to the San Joaquin basin, both regions under strong anthropogenic influence and potential conservation targets. C. pitensis limits extended historically throughout the Sacramento/Pit River basin but currently are restricted to the Pit River. Interestingly, locations in the Sacramento River contained low levels of ancestral hybridization and gene flow from C. gulosus but now appear to be a distinct population. The remaining population structure was strongly correlated with Sierra Nevada presence (high) or absence (low). This study stresses the importance of testing phylogeographic breaks across multiple taxa/habitats before conservation decisions are made, but also the potential impact of different geographic landscapes on evolutionary diversification., (© 2014 John Wiley & Sons Ltd.)

A bottleneck in population size of a species is often correlated with a sharp reduction in genetic variation. The northern elephant seal (Mirounga angustirostris) has undergone at least one extreme bottleneck, having rebounded from 20-100 individuals a century ago to over 175,000 individuals today. The relative lack of molecular-genetic variation in contemporary populations has been documented, but the extent of variation before the late 19th century remains unknown. We have determined the nucleotide sequence of a 179 base-pair segment of the mitochondrial DNA (mtDNA) control region from seals that lived before, during and after a bottleneck low in 1892. A 'primerless' PCR was used to improve the recovery of information from older samples. Only two mtDNA genotypes were present in all 150+ seals from the 1892 bottleneck on, but we discovered four genotypes in five pre-bottleneck seals. This suggests a much greater amount of mtDNA genotypic variation before this bottleneck, and that the persistence of two genotypes today is a consequence of random lineage sampling. We cannot correlate the loss of mtDNA genotypes with a lowered mean fitness of individuals in the species today. However, we show that the species historically possessed additional genotypes to those present now, and that sampling of ancient DNA could elucidate the genetic consequences of severe reductions in population size.