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Eulachon (Thaleichthys pacificus), a culturally and ecologically important anadromous smelt (Family Osmeridae), ranges from Northern California to the southeast Bering Sea. In recent decades, some populations have experienced declines. Here we use a contig-level genome assembly combined with previously published restriction site-associated DNA sequencing (RADseq)-derived markers to construct an amplicon panel for eulachon. Using this panel, we develop a filtered genetic baseline of 521 variant loci genotyped in 1989 individuals from 14 populations ranging from Northern California through central Alaska. Consistent with prior genetic studies, the strongest separation occurs among three main regions: from Northern California up to and including the Fraser River; north of the Fraser River to southeast Alaska; and within the Gulf of Alaska. Separating the Fraser River from southern US populations and refining additional substructure within the central coast may be possible in mixed-stock analysis; this will be addressed in future work. The amplicon panel outperformed the previous microsatellite panel and thus will be used in future mixed-stock analyses of eulachon to provide new insights for management and conservation of eulachon. L'eulakane (Thaleichthys pacificus), un eperlan (famille des osmerides) anadrome d'importance culturelle et ecologique, est present du nord de la Californie jusqu'au sud-est de la mer de Behring. Au cours des dernieres decennies, certaines populations ont connu des declins. Nous utilisons un assemblage de genome au niveau du contig combine a des marqueurs derives du sequencage de fragments d'ADN associes a un site de restriction (RADseq) deja publies pour constituer un panel d'amplicons pour les eulakanes. A l'aide de ce panel, nous etablissons une base de reference genetique filtree de 521 sites de variants genotypes dans 1989 specimens issus de 14 populations allant du nord de la Californie au centre de l'Alaska. A l'instar de resultats d'etudes genetiques anterieures, la plus forte separation est observee pour trois regions principales, soit du nord de la Californie jusqu'au fleuve Fraser, inclusivement, du nord du fleuve Fraser jusqu'au sud-est de l'Alaska, et dans le golfe d'Alaska. Il pourrait etre possible, dans l'analyse de stocks melanges, de separer les populations du fleuve Fraser de celles du sud des Etats-Unis et d'obtenir une sous-structure plus fine pour le littoral central; cela fera l'objet de travaux futurs. Le panel d'amplicons donne de meilleurs resultats que le groupe de marqueurs microsatellites anterieur et sera donc utilise dans des analyses futures de stocks melanges d'eulakanes afin d'obtenir des renseignements utiles pour la gestion et la conservation de ce poisson. [Traduit par la Redaction], Introduction Eulachon (Thaleichthys pacificus) is a culturally and ecologically important anadromous smelt (Family Osmeridae) distributed in North America from Northern California to the southeast Bering Sea (Hay and McCarter 2000). [...]

Abstract.--The eastern gray squirrel, Sciurus carolinensis (EGS) has been introduced to California and has expanded its geographic range since initial introductions. In this study we projected the potential future geographic [...]

Abstract.--Indian Knob Mountainbalm Eriodictyon altissimum (Namaceae) is a shrub endemic to western San Luis Obispo County in central coastal California, and little has been published regarding it. The species was [...]

On 21 June 2017, Author K. Lee, diving in 29 m of water at Esalen Pinnacle (36[degrees]07.6'N, 121[degrees]39'W), central California, photographed a fish we have identified as Asemichthys taylori Gilbert, [...]

We report here on the first observations of the Panamic fanged blenny, Ophioblennius steindachneri Jordan & Evermann, 1898, in California marine waters. In addition, we provide information on the other [...]

Abstract: Five species of stalked crinoids collected at depths from 1,693 to 4,13 5 m off the California coast, chiefly on seamounts, are described. Four were photographed in situ and [...]

We report here on the first observations and capture of breeding populations of the largemouth blenny, Labrisomus xanti Gill, 1860 (Family Labrisomidae) in California marine waters. We also provide a [...]

Abstract.--Chorro Creek bog thistle Cirsium fontinale var. obispoense (Asteraceae) is a biennial or short-lived perennial plant up to 2 m tall that occurs only in San Luis Obispo County, west [...]

We report here on the first documented occurrences of the whitetail damselfish, Stegastes leucorus (Gilbert, 1892), in California and adjacent marine waters. Also, we provide a list of damselfishes (Pomacentridae) [...]

We examined the dynamics of aboveground forest woody carbon pools--live trees, standing dead trees, and down wood--during the first 6 years following wildfire across a wide range of conditions, which are characteristic of California forest fires. From repeated measurements of the same plots, we estimated change in woody carbon pools as a function of crown fire severity as indicated by a post-fire index, years since fire, pre-fire woody carbon, forest type group (hardwood vs. softwood), elevation, and climate attributes. Our analysis relied on 130 U.S. national forest inventory plots measured before and 1 year after fire, with one additional remeasurement within 6 years after fire. There was no evidence of net change in total wood carbon, defined for this study as the wood in standing trees larger than 12.7 cm diameter at breast height and down wood larger than 7.6 cm in diameter, over the post-fire period in any of the three severity classes. Stands that burned at low severity exhibited considerable shifts from live to standing dead and down wood pools. In stands that burned at moderate severity, live wood decreased significantly whereas no net change was detected in standing dead or down wood. High severity fire burning resulted in movement from standing dead to down wood pools. Our results suggest that the carbon trajectories for stand-replacing fires may not be appropriate for the majority of California's forest area that burned at low to moderate severities. Key words: longitudinal analysis, post-fire dynamics, forest stand recovery, disturbance, Forest Inventory and Analysis. Nous avons etudie la dynamique des reservoirs de carbone ligneux de la partie aerienne des forets (les arbres vivants, les arbres morts sur pied et au sol) au cours des six premieres annees apres un feu pour une large gamme de conditions caracteristiques des feux de foret de la Californie. A partir de mesures repetees des memes placettes, nous avons estime les changements dans les reservoirs de carbone ligneux en fonction de la severite des dommages a la cime des arbres selon un indice apres feu, du nombre d'annees apres le feu, du carbone ligneux avant le feu, du groupe de types forestiers (feuillus ou resineux), de l'altitude et des caracteristiques du climat. Nos analyses ont porte sur 130 placettes de l'inventaire national etats-unien (FIA) mesurees avant et un an apres le feu de meme qu'une autre fois au cours des six premieres annees apres le feu. Il n'y a pas eu d'indices de changement net du carbone ligneux total apres feu, correspondant dans cette etude au bois des arbres sur pied ayant un diametre a hauteur de poitrine plus grand que 12,7 cm et des arbres au sol ayant un diametre superieur a 7,6 cm, dans aucune des trois classes de severite du feu. Les peuplements ayant subi un feu de severite faible ont connu des changements considerables dans les reservoirs de carbone ligneux, passant d'une dominance d'arbres vivants a une dominance d'arbres morts sur pied et au sol. Dans les peuplements brules par un feu de severite moderee, les arbres vivants ont diminue significativement alors qu'aucun changement net n'a ete detecte chez les arbres morts sur pied ou au sol. Le feu de severite elevee a provoque un deplacement de reservoir ligneux des arbres morts sur pied vers les arbres au sol. Nos resultats indiquent que les trajectoires de carbone typiques des feux qui entrainent le remplacement des peuplements peuvent ne pas etre appropriees pour les cas plus communs de peuplements subissant des feux d'intensites faible a moderee. [Traduit par la Redaction] Mots-cles: analyse longitudinale, dynamique apres feu, retablissement des peuplements forestiers, perturbation, programme d'analyse et d'inventaire forestiers (FIA)., Introduction Natural disturbances such as wildfire are increasing in frequency, severity, and extent across forested ecosystems of the western U.S. (Westerling et al. 2006; Miller et al. 2009; Stephens 2005; [...]

Abstract.--There is a need for a consolidated source of information on native vegetation seed collection and germination strategies in southern California. Published literature on these methods is often experimental, species-specific, [...]

Hansen (1897), dealing with only fragmentary material, erected the genus Bathygyge with B. grandis as its type-species as one of the earliest bopyrid species known from the eastern Pacific Ocean. [...]

Abstract.--It is rare to find evidence of top predators recovering after being negatively affected by overfishing. However, recent findings suggest a nascent return of the critically endangered giant sea bass [...]