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The California Spotted Owl (Strix occidentalis occidentalis ) is under consideration for federal protection and has stimulated ecosystem-level management efforts in Sierra Nevada national forests. Because some populations are declining, we used a noninvasive fecal sampling method to estimate stress hormone (i.e., corticosterone) levels within a local population from April to August 2001. Fecal corticosterone levels were similar to those recorded in a previous study of Northern Spotted Owls (S.o. caurina ) ( &xmacr;= 80.1 ng/g dry feces, SE = 75.8). We then used an information-theoretic approach to identify factors that influence fecal corticosterone levels in Spotted Owls. Our best overall model indicated that nonbreeding owls had higher fecal corticosterone levels than breeding owls early in the breeding season and lower levels later in the breeding season. We collected few samples from breeding owls early in the breeding season, however, which may have influenced the results. Management-related factors reflecting habitat condition and proximity to roads were not correlated with fecal corticosterone. However, factors such as field storage method and sample mass were correlated with the amount of measured fecal corticosterone and should be considered in future studies. Sample vials initially stored on ice had higher levels than those stored immediately in liquid N2 (βstorage= 0.269 ln[ng/g], 95% CI = 0.026, 0.512). Hormone metabolites were extracted from extremely small samples (0.01 g) by slightly modifying the assay protocol, but the amount of corticosterone detected increased as the sample mass decreased (βmass=−6.248 ln[ng/g], 95% CI =−8.877, −3.620). Corticosterone levels were significantly higher in 10 cecal samples collected simultaneously with fecal samples (paired difference = 74.7 ng/g, SE = 45.0, p = 0.001 for a paired t test), so care must be taken to avoid contaminating fecal samples with cecal material. Most of the variation was unexplained by our best model ( R 2= 0.24), and additional factors influencing fecal corticosterone levels need to be identified. Therefore, we recommend that well-designed experiments be conducted under controlled conditions to better determine the effect of factors such as sample handling, partial sampling, and diet on fecal corticosterone levels in owls and other birds. [ABSTRACT FROM AUTHOR]

Focuses on the intervention and persistence in small populations of bighorn sheep in California. Relationship between population size and extinction; Risk in using single demographic parameters for the prediction of extinction; Use of biogeographic theory in conservation.

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Decimation of the California (U.S.A.) prairie has increased interest in the conservation and ecological restoration of grasslands composed of native perennial species. Widespread plantings are being attempted, and the potential for contaminating existing remnant populations with maladapted germplasm has led to concerns about the use of nonlocal seed sources. We evaluated regional patterns of isozyme and quantitative trait variation in the native perennial grass Nassella pulchra for the purpose of developing recommendations about the spatial scales over which seed can be translocated. Seed was collected from 10 remnant native populations. Progeny from all 10 populations were scored for isozyme variation with 11 stains, and progeny from 8 populations were planted in a common garden to evaluate variation for 11 quantitative (polygenic) traits. The correspondence between isozyme and quantitative trait variation and the relationships of both types of variation to geographic distance and climate were explored by Mantel test regressions. Populations were strongly differentiated for both isozymes and quantitative traits, but cluster analysis based on each type of data did not result in the same population groupings. This lack of congruence was further demonstrated by the nonsignificance of the regression of Hedrick's distances for isozymes on Mahalanobis distances for quantitative traits. Quantitative trait variation was strongly associated with climatic variables, whereas isozyme variation was not. This suggests that the relative importance of genetic drift and selection in shaping patterns of genetic differentiation may depend upon the type of trait evaluated. Quantitative traits are potentially better indicators of adaptation to regional and local environmental variation, and thus the usefulness of isozymes for making recommendations about the spatial scales over which seed of N. pulchra can be translocated may be limited. Unfortunately, obtaining data on patterns of quantitative trait variation is often time‐ and labor‐intensive. The close association of quantitative trait variation with regional climatic variables indicates that an index based on readily obtainable climatic information might aid restorationists in making rapid decisions about appropriate spatial scales for translocating native grasses. Compariciones de Isozimas y Rasgos Cuantitativos para Evaluar Patrones de Variación Genética en el Pasto‐Aguja Morado (Nasella pulchra) La disminución de la pradera de California (USA) ha incrementado el interés en la conservación y restauración ecológica de pastizales compuestos por especies perennes nativas. La dispersión amplia de siembras se ha intentado y el potencial de contaminación de poblaciones remanentes con germoplasmas mal adaptados ha generado preocupaciones sobre el uso de fuentes de semilla no locales. Evaluamos patrones regionales de variación de isozimas y variación cuantitativa de rasgos en el pasto perenne nativo Nasella pulchra con el propósito de desarrollar recomendaciones sobre las escalas espaciales en las cuales las semillas pueden ser movidas. Las semillas fueron colectadas a partir de 10 poblaciones remanentes nativas. Las progenies de las 10 poblaciones fueron evaluados para variación de isozima usando 11 colorantes y las progenies de 8 poblaciones fueron plantadas en un jardín común para evaluar la variación de 11 rasgos (poligenéticos) cuantitativos. La correspondencia entre variaciones de isozimas y de rasgos cuantitativos y las relaciones de ambos tipos de variación con distancia geográfica y clima fue explorada usando pruebas de regresión de Mantel. Sin embargo, los análisis de conjunto basados en cada tipo de datos no dió como resultado las mismas agrupaciones de poblaciones. Esta carencia de congruencia fue demonstrada más adelante por la no significancia de la regresión de distancias de Hendrick para isozimas en distancias Mahalanobis para rasgos cuantitativos. La variación en rasgos cuantitativos estuvo fuertemente asociada con las variables climáticas, mientras que la variación de isozimas no lo estuvo. Esto sugiere que la importancia relativa de la deriva génica y de la selección en patrones de forma de diferenciación genética pueden depender del tipo de rasgo evaluado. Los rasgos cuantitativos son potencialmente mejores indicadores de adaptación a la variación ambiental local y regional, por lo tanto la utildad de isozimas para hacer recomendaciones sobre escalas espaciales en las cuales las semillas de N. pulchra pueden ser movidas puede verse limitada. Desafortunadamente, la obtención de datos de patrones de variación de rasgos cuantitativos require frecuentemente de tiempo y esfuerzo intensivos. La asociación cercana de variación de rasgos cuantitativos con variables climáticas regionales indica que un indice basado en información climática accesible podría ayudar a los restauradores a tomar decisiones rápidas sobre escalas espaciales apropiadas para mover pastos nativos. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Focuses on the death of biologist Raymond F. Dasmann on November 5, 2002 in Santa Cruz, California. Contributions of Dasmann in the field of ecology; Career background of Dasmann; Accomplishments of Dasmann.

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)