@mastersthesis {186, title = {Modelaci{\'o}n y Caracterizaci{\'o}n Ambiental del {\'A}rea de Distribuci{\'o}n Potencial de Oncorhynchus chrysogaster (Needham y Gard, 1964) en las Cuencas de los R{\'\i}os Sinaloa y Culiac{\'a}n}, year = {2015}, month = {2015/01//}, pages = {1-74}, school = {Centro de Investigaci{\'o}n en Alimentaci{\'o}n y Desarrollo, A.C.}, address = {Mazatl{\'a}n, Sinaloa, M{\'e}xico}, abstract = {Regarding the Mexican golden trout Oncorhynchus chrysogaster, salmonid nativeto Mexico which distribution has been restricted to river basins Fuerte, Sinaloa, Culiacan in the Sierra Madre Occidental (SMO). However, this study focused on modeling the potential distribution of this species in the basins of Sinaloa and Culiac{\'a}n rivers, bounded at altitudes >= 1500 m, being little studied in relation to the distribution of this species. There are few historical records of the species, extending to the present study with 11 new records obtained in four samples taken during the investigation. The environmental information required for the modeling process comes from the bioclimatic variables WorldClim and Compound Topographic Index HYDRO1k project. Based on this information and the records of the species, the potential distribution of the species with BIOCLIM, GARP and MAXENT methods that relate common occurrence data (geographical location) of one species with the set of environmental variables was modeled. The three models agree in locating distribution sites above 1500 m, which is considered as altitudinal limit, however there are differences in the extent and final distribution area, having higher affinity to the results obtained with GARP and MAXENT, compared with results generated with BIOCLIM. To assess the predictive ability of different modeling methods mentioned before a statistical method known as Jackknife resampling, which is appropriate when you have fewer than 25 records of occurrence was applied. The model validation GARP places as the method has a higher predictive success, followed by MAXENT. Con relaci{\'o}n a la trucha dorada mexicana Oncorhynchus chrysogaster, salm{\'o}nido nativo de M{\'e}xico cuya distribuci{\'o}n se ha restringido a las cuencas de los r{\'\i}os Fuerte, Sinaloa y Culiac{\'a}n, en la Sierra Madre Occidental (SMO). A pesar de ello, el presente estudio se centr{\'o} en el modelado de la distribuci{\'o}n potencial de esta especie en las cuencas de los r{\'\i}os Sinaloa y Culiac{\'a}n, acotadas a altitudes >= 1500 msnm, por estar escasamente estudiadas con relaci{\'o}n a la distribuci{\'o}n de esta especie. Dentro de esta {\'a}rea se cuenta con pocos registros hist{\'o}ricos de presencia de la especie, ampli{\'a}ndose con el presente estudio con 11 registros nuevos obtenidos en cuatro muestreos realizadas durante la investigaci{\'o}n. La informaci{\'o}n ambiental requerida para el proceso de modelado procede de las variables bioclim{\'a}ticas de WorldClim y el {\'I}ndice Compuesto Topogr{\'a}fico del proyecto HYDRO1k. Con base en dicha informaci{\'o}n y con los registros de la especie, se model{\'o} la distribuci{\'o}n potencial de la especie con los m{\'e}todos BIOCLIM, GARP y MAXENT, que en com{\'u}n relacionan datos de presencia (posici{\'o}n geogr{\'a}fica) de una especie con el conjunto de variables ambientales. Los tres modelos coinciden en ubicar los sitios de distribuci{\'o}n por arriba de los 1500 msnm, que se ha considerado como l{\'\i}mite altitudinal, sin embargo existen diferencias en cuanto a la extensi{\'o}n y {\'a}rea de distribuci{\'o}n final, existiendo mayor afinidad en los resultados obtenidos con GARP y MAXENT, comparativamente con los resultados generados con BIOCLIM. Para evaluar la capacidad predictiva de los diferentes m{\'e}todos de modelaci{\'o}n mencionados anteriormente se aplic{\'o} un m{\'e}todo estad{\'\i}stico de remuestreo conocido como Jackknife, el cual es apropiado cuando se tiene menos de 25 registros de ocurrencia. La validaci{\'o}n de los modelos coloca a GARP como el m{\'e}todo que presenta un mayor {\'e}xito predictivo, seguido por MAXENT. }, keywords = {Mexican trout, Oncorhynchus chrysogaster, Sierra Madre Occidental, species distribution modelling}, author = {Ram{\'\i}rez-Huerta, Alejandro Luis} } @article {177, title = {The interplay of riverscape features and exotic introgression on the genetic structure of the Mexican golden trout (Oncorhynchus chrysogaster), a simulation approach}, journal = {Journal of Biogeography}, volume = {45}, year = {2018}, month = {2018///}, pages = {1500 - 1514}, abstract = {Aim We explored the factors between riverscape features and exotic introgression of cultured rainbow trout (Oncorhynchus mykiss) that drive the current genetic structure in the endemic Mexican golden trout (Oncorhynchus chrysogaster) using a riverscape genetics simulator. Location Sierra Madre Occidental, Northwest Mexico, North America. Methods We created a system model for Mexican golden trout to test various scenarios for the effect of riverscape resistance and rainbow trout introgression on the native genetic structure of the Mexican golden trout. Individual genotypes were used to initialize the model and were based upon empirical allele frequencies from three genetically and spatially distinct groups in the study area. The geographical location of the simulated populations was defined using a species distribution model. We included hypotheses for movement of riverine distance and riverscape resistance. We evaluated model performance by conducting population and landscape genetics analyses on the simulation outputs. Results The most plausible scenario included riverscape resistance without introgression, which presented a spatial genetic structure matching the observed riverscape genetic structure and fitting expected general life-history patterns for high elevation trout streams. In addition, temperature, precipitation, hydrology and topography were the most important variables influencing species occurrence and dispersal. Main conclusion This work presents one of the first empirically derived simulation studies of introgression. It highlights the importance of considering riverscape resistance (i.e. hydroclimatic and topographical gradient effects) in models of spatial genetic structure and introgression. Moreover, our modelling suggests that what we characterize as riverscape resistance is acting as a boundary against exotic introgression. The results of this study could help to develop management strategies that preserve native gene pools.}, keywords = {CDMetaPOP, exotic trout, Mexican trout, Oncorhynchus chrysogaster, rainbow trout, riverscape genetics, species distribution modelling, Truchas Mexicanas}, isbn = {1365-2699}, url = {http://onlinelibrary.wiley.com/doi/abs/10.1111/jbi.13246}, author = {Escalante, Marco Alejandro and Le{\'o}n, Francisco J. Garc{\'\i}a-De and Ruiz-Luna, Arturo and Landguth, Erin and Manel, St{\'e}phanie} } @mastersthesis {169, title = {Genetic Investigation Of The Pacific Trout Complex: From Pedigrees To Phylogenies}, year = {2014}, month = {2014/01/01/}, pages = {164}, school = {University of California Santa Cruz}, address = {Santa Cruz, California}, abstract = {Perhaps one of the world{\textquoteright}s most important groups of fish are the species within the Pacific trout complex, due to their harvest in fisheries and use in aquaculture. This dissertation consists of an in-depth evaluation of this group at different scales, from the assessment of biological traits throughout the reconstruction of pedigrees in two populations to a phylogeographic examination of multiple largely undescribed species. Here, a combination of novel molecular techniques allowed me to address critical ecological questions for the management and conservation of this group.In chapter one, I describe the discovery, characterization and development of single nucleotide polymorphisms for O. mykiss for the study of ecological interactions, phylogeography, and conservation status. These tools have great power for population genetic analysis, and for individual identification and pedigree reconstruction. The last allows the tracking of families, and an unprecedented level of evaluation of natural and hatchery populations.Chapter two expands the scope of these molecular tools to provide a powerful means of understanding of biological traits for steelhead hatchery programs in the Russian River, California. Reconstruction of cohort age distributions revealed a strong component of fish that spawn at age two, in contrast to program goals and distinct from naturally spawning steelhead. Correlations between family members in the day of spawning revealed a strongly heritable component to this life history trait and demonstrated the potential for selection to alter life history traits. These results demonstrate the promise of SNP-based pedigree reconstruction for providing biological inference in high-fecundity organisms.Chapter three describes how the molecular tools developed were applied to population genetics of trout inhabiting northwestern Mexico, to elucidate biodiversity, and evolutionary history, and measure introgression from hatchery rainbow trout. Here, I confirmed the vast genetic diversity present in northwestern Mexican trout and provided evidence that trout inhabiting the Sierra Madre Occidental correspond to independent lineages separated from O. mykiss. Introgression from non-native trout was detected, but the genetic integrity of native trout is still maintained. All the information presented in this document will help to guide effective conservation strategies for this globally important group of fishes.}, keywords = {Conservation biology, Ecology, Genetics, Mexican trout, Microsatellites, Oncorhynchus, Pedigrees, Phylogenetics, Population genetics, Single nucleotride polymorphisms, Truchas Mexicanas}, url = {http://escholarship.org/uc/item/4ks0b0sm}, author = {Abad{\'\i}a-Cardoso, Alicia} } @mastersthesis {170, title = {Modelaci{\'o}n y Caracterizaci{\'o}n Ambiental del {\'A}rea de Distribuci{\'o}n Potencial de Oncorhynchus chrysogaster (Needham y Gard, 1964) en las Cuencas de los R{\'\i}os Sinaloa y Culiac{\'a}n}, year = {2015}, month = {2015/01//}, pages = {1-74}, school = {Centro de Investigaci{\'o}n en Alimentaci{\'o}n y Desarrollo, A.C.}, address = {Mazatl{\'a}n, Sinaloa, M{\'e}xico}, abstract = {Regarding the Mexican golden trout Oncorhynchus chrysogaster, salmonid nativeto Mexico which distribution has been restricted to river basins Fuerte, Sinaloa, Culiacan in the Sierra Madre Occidental (SMO). However, this study focused on modeling the potential distribution of this species in the basins of Sinaloa and Culiac{\'a}n rivers, bounded at altitudes >= 1500 m, being little studied in relation to the distribution of this species. There are few historical records of the species, extending to the present study with 11 new records obtained in four samples taken during the investigation. The environmental information required for the modeling process comes from the bioclimatic variables WorldClim and Compound Topographic Index HYDRO1k project. Based on this information and the records of the species, the potential distribution of the species with BIOCLIM, GARP and MAXENT methods that relate common occurrence data (geographical location) of one species with the set of environmental variables was modeled. The three models agree in locating distribution sites above 1500 m, which is considered as altitudinal limit, however there are differences in the extent and final distribution area, having higher affinity to the results obtained with GARP and MAXENT, compared with results generated with BIOCLIM. To assess the predictive ability of different modeling methods mentioned before a statistical method known as Jackknife resampling, which is appropriate when you have fewer than 25 records of occurrence was applied. The model validation GARP places as the method has a higher predictive success, followed by MAXENT. Con relaci{\'o}n a la trucha dorada mexicana Oncorhynchus chrysogaster, salm{\'o}nido nativo de M{\'e}xico cuya distribuci{\'o}n se ha restringido a las cuencas de los r{\'\i}os Fuerte, Sinaloa y Culiac{\'a}n, en la Sierra Madre Occidental (SMO). A pesar de ello, el presente estudio se centr{\'o} en el modelado de la distribuci{\'o}n potencial de esta especie en las cuencas de los r{\'\i}os Sinaloa y Culiac{\'a}n, acotadas a altitudes >= 1500 msnm, por estar escasamente estudiadas con relaci{\'o}n a la distribuci{\'o}n de esta especie. Dentro de esta {\'a}rea se cuenta con pocos registros hist{\'o}ricos de presencia de la especie, ampli{\'a}ndose con el presente estudio con 11 registros nuevos obtenidos en cuatro muestreos realizadas durante la investigaci{\'o}n. La informaci{\'o}n ambiental requerida para el proceso de modelado procede de las variables bioclim{\'a}ticas de WorldClim y el {\'I}ndice Compuesto Topogr{\'a}fico del proyecto HYDRO1k. Con base en dicha informaci{\'o}n y con los registros de la especie, se model{\'o} la distribuci{\'o}n potencial de la especie con los m{\'e}todos BIOCLIM, GARP y MAXENT, que en com{\'u}n relacionan datos de presencia (posici{\'o}n geogr{\'a}fica) de una especie con el conjunto de variables ambientales. Los tres modelos coinciden en ubicar los sitios de distribuci{\'o}n por arriba de los 1500 msnm, que se ha considerado como l{\'\i}mite altitudinal, sin embargo existen diferencias en cuanto a la extensi{\'o}n y {\'a}rea de distribuci{\'o}n final, existiendo mayor afinidad en los resultados obtenidos con GARP y MAXENT, comparativamente con los resultados generados con BIOCLIM. Para evaluar la capacidad predictiva de los diferentes m{\'e}todos de modelaci{\'o}n mencionados anteriormente se aplic{\'o} un m{\'e}todo estad{\'\i}stico de remuestreo conocido como Jackknife, el cual es apropiado cuando se tiene menos de 25 registros de ocurrencia. La validaci{\'o}n de los modelos coloca a GARP como el m{\'e}todo que presenta un mayor {\'e}xito predictivo, seguido por MAXENT. }, keywords = {Mexican trout, Oncorhynchus chrysogaster, Sierra Madre Occidental, species distribution modelling}, author = {Ram{\'\i}rez-Huerta, Alejandro Luis} } @article {157, title = {Modelaci{\'o}n de la distribuci{\'o}n de truchas nativas de la Sierra Madre Occidental y su relaci{\'o}n con la estructura del paisaje adyacente}, journal = {GBIF.org}, year = {2020}, month = {2020/03/30/}, abstract = {El proyecto se centra en el estudio de truchas nativas de M{\'e}xico, que se distribuyen en la Sierra Madre Occidental. Se reconoce la existencia de la especie Oncorhynchus chrysogaster (Needham y Gard, 1964), denominada Trucha dorada mexicana (PISCES: Salmonidae), misma que est{\'a} reportada como especie end{\'e}mica amenazada en la NOM-059-SEMARNAT-2010 y como especie vulnerable en CITES (Conference on International Trade in Endangered Species). La situaci{\'o}n de riesgo es a{\'u}n m{\'a}s grave si se considera que estudios recientes indican que por la heterogeneidad gen{\'e}tica de este complejo de peces, es posible la identificaci{\'o}n de nuevas especies o subespecies de truchas nativas (Hendrickson et al., 2002, Hendrickson et al., 2006). Considerando lo anterior y tomando en cuenta que existen algunas iniciativas (particularmente realizadas por acad{\'e}micos estadounidenses y mexicanos), enfocadas al estudio sistem{\'a}tico y gen{\'e}tico de este grupo de peces, se propone complementarlas con el an{\'a}lisis espacial del paisaje del {\'a}rea de distribuci{\'o}n potencial de O. chrysogaster. Para ello se analizar{\'a}n los registros hist{\'o}ricos, los datos existentes con referencia geogr{\'a}fica espec{\'\i}fica y adicionalmente los datos que se generen a partir de este proyecto, para producir un modelo de distribuci{\'o}n de esta especie en la Sierra Madre Occidental. Dado el escaso registro con que se cuenta se considera indispensable la colecta con fines de ampliar dicho registro, pero particularmente con la intenci{\'o}n de validar en lo posible el modelo que se genere. Se aplicar{\'a}n t{\'e}cnicas de percepci{\'o}n remota que permitir{\'a}n identificar las caracter{\'\i}sticas ambientales de las localidades de registro (red hidr{\'a}ulica, altitud, pendiente, tipos de cobertura) y que podr{\'a}n ser incorporadas a un sistema de informaci{\'o}n geogr{\'a}fica (SIG), conjuntamente con informaci{\'o}n auxiliar (temperaturas promedio, precipitaci{\'o}n, geolog{\'\i}a, etc.). La identificaci{\'o}n de estas caracter{\'\i}sticas, en conjunto con datos de la presencia/ausencia de las truchas permitir{\'a} generar mapas de susceptibilidad de las {\'a}reas de distribuci{\'o}n de estas especies por medio de modelos del nicho ecol{\'o}gico, por ejemplo MAXENT y Mahalanobis.}, keywords = {Mexican trout, Oncorhynchus chrysogaster}, url = {https://www.gbif.org/dataset/90711430-4260-422f-aeb2-26ce7f72f56c}, author = {Ruiz Luna, Arturo} } @article {110, title = {SGER: Biodiversity of Native Mexican Trout (Genus Oncorhynchus spp.) and The Impending Treat of Their Demise by The Exotic Rainbow Trout O. mykiss gairdneri (Teleostei: Salmonidae). DEB 0240184}, year = {2006}, month = {2006///}, keywords = {Mexican trout, Truchas Mexicanas}, isbn = {DEB 0240184}, url = {http://bio.slu.edu/mayden/truchas/NSF_trout_final_report.pdf}, author = {Mayden, Richard L.} } @article {23, title = {Genetic introgression of cultured rainbow trout in the Mexican native trout complex}, journal = {Conservation Genetics}, volume = {15}, year = {2014}, month = {2014/10/01/}, pages = {1063 - 1071}, abstract = {

The Mexican native trout complex is the group of salmonids that naturally has the southernmost distribution in the world. Despite its unique status and evidence of more than 13 distinct lineages, there are only two described species (Oncorhynchus mykiss nelsoni and O. chrysogaster). These fishes are threatened by environmental and anthropogenic factors, most notably the introduction of the exotic species O. mykiss (rainbow trout) for aquaculture. Here we applied population genetics analysis in 1,017 wild and cultured trout to understand the extent of genetic introgression of rainbow trout in Mexican native trout. Present results indicate a high degree of introgression and genetic admixture among introduced rainbow trout and some populations of Mexican native trout, exposing them to loss of genetic diversity. Thus, introduction of exotic trout for aquaculture purposes must be strictly regulated or avoided and we advise the use of native trout for aquaculture.

}, keywords = {Genetic hybridization, genetic introgression, Mexican trout, Northwestern Mexico, rainbow trout, Sierra Madre Occidental, Truchas Mexicanas}, isbn = {1566-0621}, url = {http://dx.doi.org/10.1007/s10592-014-0599-7}, author = {Escalante, MarcoA. and Garc{\'\i}a-De-Le{\'o}n, FranciscoJ. and Dillman, CaseyB. and de los Santos Camarillo, Anabelia and George, Anna and de los A. Barriga-Sosa, Irene and Ruiz-Luna, Arturo and Mayden, RichardL. and Manel, St{\'e}phanie} } @article {16, title = {Mitochondrial haplotype variation in wild trout populations (Teleostei: Salmonidae) from northwestern Mexico}, journal = {Reviews in Fish Biology and Fisheries}, volume = {18}, year = {2008}, month = {2008///}, pages = {33 - 45}, abstract = {

The variation and composition of Mexican wild trout mitochondrial DNA haplotypes throughout northwestern Mexico was determined by means of polymerase chain reaction-restriction fragment polymorphism analysis (PCR-RFLP), of one region of mitochondrial DNA between cytochrome b and the D-loop. This analysis was based on 261 specimens taken in 12 basins and four hatcheries from northwestern Mexico. From 23 haplotypes, 15 wild trout haplotypes were identified and classified in four groups: (1) one restricted to Nelson\&$\#$39;s trout (Oncorhynchus mykiss nelsoni), (2) four restricted to R\¡o Mayo and R\¡oYaqui trout (O. mykiss sspp.), (3) six to Mexican golden trout (O. chrysogaster) with two subgroups, and (4) one exclusive to R\¡o Piaxtla trout. Distributions of native haplotypes broadly overlap the distribution of non-native hatchery rainbow trout reflecting the historical management of introductions of exotic rainbow trout and the artificial transference of these trout among basins.

}, keywords = {Chihuahua, Conchos, Cytochrome b, endangered, Mayo, Mexican trout, Oncorhynchus, Oncorhynchus mykiss, rainbow trout, Salmonidae, Truchas Mexicanas}, url = {⬚d:\users\dean_h\reprints in pdf or other\Camarena_2008_Mt_haplotype_Mexican_trout.pdf⬚}, author = {Camarena-Rosales, Faustino and Ruiz-Campos, Gorgonio and Rosa-V{\'e}lez, Jorge and Mayden, Richard L. and Hendrickson, Dean A. and Varela-Romero, Alejandro and Garc{\'\i}a de Le{\'o}n, Francisco J.} } @article {21, title = {Isolation and characterization of 17 tetranucleotide microsatellite loci in the Mexican golden trout (Oncorhynchus chrysogaster, Needham \& Gard 1964) derived from 454 pyrosequencing}, journal = {Conservation Genetics Resources}, volume = {5}, year = {2013}, month = {2013/05/14/}, pages = {1009 - 1012}, abstract = {

We present seventeen microsatellite loci developed for the Mexican golden trout Oncorhynchus chrysogaster through GS-FLX 454 pyrosequencing. We selected 34 primer pairs tested on 19 trout specimens from The Rio Verde (Rio Fuerte Bain) and we tested cross amplification on 35 trout specimens collected in seven hydrological basins from the Sierra Madre Occidental and Sierra San Pedro M\ártir, as well as five hatchery reared Oncorhynchus mykiss. We observed medium and high genetic variation among loci (mean number of alleles per locus = 8.0, SD = 2.92; mean H O = 0.65, SD = 0.27). These loci are the first to be characterized explicitly for O. chrysogaster and they are expected to be useful for population studies in this species and as reference for species delimitation.

}, keywords = {Mexican golden trout, Mexican trout, Oncorhynchus chrysogaster, Sierra Madre Occidental, Truchas Mexicanas}, isbn = {1877-7252, 1877-7260}, url = {http://link.springer.com/article/10.1007/s12686-013-9956-y}, author = {Garc{\'\i}a-De-Le{\'o}n, Francisco J. and Lozano-Garza, O. Adri{\'a}n and Mayden, Richard L. and Delgado-Vega, Rigoberto and Camarena-Rosales, Faustino and Ruiz-Campos, Gorgonio and Escalante-S{\'a}nchez, Marco A. and Ruiz-Luna, Arturo and R{\'\i}o-Portilla, Miguel {\'A}ngel Del and Barriga-Sosa, Irene de los A. and Arcos-Ortega, Guadalupe Fabiola and Paniagua-Ch{\'a}vez, Carmen} } @inbook {15, title = {Conservation of Mexican native trout and the discovery, status, protection and recovery of the Conchos trout, the first native Oncorhynchus of the Atlantic drainage in Mexico}, booktitle = {Studies of North American Desert Fishes in Honor of E. P. (Phil) Pister, Conservationist}, year = {2007}, note = {

d:\users\dean_h\reprints in pdf or other\Hendrickson_etal_2007_conservation_Mexican_trout.pdf

}, month = {2007///}, pages = {162 - 201}, publisher = {Direcci{\'o}n de Publicaciones, Universidad Aut{\'o}noma de Nuevo Le{\'o}n, Facultad de Ciencias Biol{\'o}gicas}, organization = {Direcci{\'o}n de Publicaciones, Universidad Aut{\'o}noma de Nuevo Le{\'o}n, Facultad de Ciencias Biol{\'o}gicas}, address = {Monterrey, Nuevo Le{\'o}n, M{\'e}xico}, abstract = {

The Northwestern Sierra Madre Occidental of Mexico is a rugged mountain range covering portions of Sonora, Chihuahua, Durango and Sinaloa, and is drained by multiple Pacific Slope Rivers to the west and the Casas Grandes, Conchos, and Nazas to the east. The overall area is topographically, climatically and biotically diverse, ranging from endorheic basins (Casas Grandes) to mountainous areas elevations up to 3348 m, average mean temperatures from 10-20\°C and precipitation from 250- 1100 mm/yr. The region is also geological complex that, combined with these other variables, provides a great diversity of both aquatic and terrestrial habitats conducive to both biotic endemicity and diversity. The overall diversity of the region has contribiited to the recent listing of this region by Conservation International as one of six new high-priority biodiversity hotspots. Our understanding of the aquatic and terrestrial biodiversity of this region, however, is poor and in urgent need of rapid investigation by collaborative communities. The combination of an incredibly rugged landscape, drug and bandit activities and indigenous peoples that have not always been welcoming to visitors has resulted in a general paucity of roads in the region, and the lack of access has limited inventory studies. Recently, however, access to the region has changed dramatically and many of the areas are now accessible enough for logging, mining, and agriculture practices, all exerting extreme pressures in some areas on the biodiversity. In addition to human-induced changes to these diverse ecosystems, impacts of invasive aquatic species are becoming more and more apparent, and the potential for severely reducing population sizes of species or their extirpation or extinction is real. While several invasive or exotic species are identified as potentially destructive to these communities, the exotic Rainbow Trout (Oncorhynchus mykiss) that is derived from hatcheries or culture facilities within the region represents one of the most critical threats to the aquatic and semi-aquatic biodiversity. The native trout of mainland Mexico represent the southern- most salmonids, and are at imminent risk of introgression and/or replacement by feral Rainbow Trout, Oncorhynchus mykiss. Our recent survey efforts have expanded the known diversity and ranges of each of several distinct forms, which we feel represent valid species. We discuss our discovery of multiple new species from the Sierra Madre Occidental and focus on a new species of trout restricted to the upper Conchos drainage, the first native species of Oncorhynchus known to occupy the Atlantic Slope in Mexico. Many of these taxa are restricted to small areas of intact habitat in headwater areas of high-elevation streams, and are at risk from a suite of human-associated perturbations, emerging diseases, and introduced species. These fishes occupy unique habitats, and represent a diverse portion of the Mexican montane ichthyofauna. The habitats on which they depend support a wide range of other aquatic organisms, most of which are grossly understudied. The discovery of the Conchos Trout derived primarily by GARP niche modeling of a subset of localities of previously sampled undescribed native Mexican trout, provides only a snapshot of the biodiversity awaiting to be discovered in this region. The rugged landscape of the Sierra Madre Occidental simply precludes routine sampling at easily accesible locations of streams and most sampling locations require time-intensive access. In an effort to rapidly assess the biodiversity of rivers of this region we employed this method to aid in predicting the most suitable and highly probable Mexican trout niches in the region. This method offered highly efficient and powerful results that not only predicted the occurrence of a previously unknown trout in the upper Rio Conchos but also provided excellent predictions of available habitats in drainages where previously unknown trout have been discovered by the Truchas Mexicanas team in the last nine years. Multiple threats exist to the biodiversity of the northern Sierra Madre Occidental, including uncontrolled introductions of exotic and invasive species, emerging diseases such as whirling disease, Myxobolus cerebralis, infectious pancreatic necrosis (IPN), iridioviruses and pathogenic water mold, Saprolegnia ferax, land-use practices leading to habitat degradation via overgrazing, logging, deforestation and road construction, increasing human population growth, over-fishing or overharvesting of aquatic resources and global climate cliange reducing surface and ground water in the area and creating environments more conducive to the spread of invasive species, congregated and dense human populations, and emerging diseases. Immediate actions need to be developed to aid in public education as to the threats to these ecosystems, protection of areas, assessment of diversity, and sustainable development throughout the region that incorporates a likely highly successful ecotourism system for the region.

}, keywords = {Atlantic, Chihuahua, conservation, desert, Durango, Ecosystem, fishes, Mexican trout, MEXICO, Oncorhynchus, recovery, Rio Conchos, Sinaloa, Sonora, Truchas Mexicanas}, isbn = {970-694-336-6}, author = {Hendrickson, Dean A. and Neely, David A. and Mayden, Richard L. and Anderson, K. and Brooks, James E. and Camarena-Rosales, Faustino and Cutter, Ralph F. and Cutter, Lisa and De Los Santos Camarillo, Ana Belia and Ernsting, Guy W. and Espinosa-P{\'e}rez, H{\'e}ctor and Findley, Lloyd T. and Garc{\'\i}a de Le{\'o}n, Francisco J. and George, A.L. and Hatch, John and Kuhajda, Bernanrd R. and Mayden, Kyle E. and McNyset, Kristina M. and Nielsen, Jennifer L. and Pfeiffer, Frank W. and Propst, David L. and Ruiz-Campos, Gorgonio and St.Clair, E. and Tomelleri, Joseph R. and Varela-Romero, Alejandro}, editor = {Lozano-Vilano, Ma. de Lourdes and Contreras-Balderas, Armando J.} } @article {6, title = {Fishes of the R{\'\i}o Yaqui Basin, M{\'e}xico and United States}, journal = {Journal of the Arizona-Nevada Academy of Science}, volume = {15}, year = {1980}, month = {1980///}, pages = {65 - 106}, keywords = {Ictalurus pricei, Mexican trout}, isbn = {01938509}, url = {http://www.jstor.org/stable/40025038}, author = {Hendrickson, Dean A. and Minckley, W. L. and Miller, Robert R. and Siebart, Darrel J. and Minckley, Patricia Haddock} } @article {3, title = {Rainbow trout in Mexico and California with notes on the cutthroat series}, journal = {University of California Publications in Zoology}, volume = {67(1)}, year = {1959}, month = {1959///}, pages = {1 - 124}, keywords = {Mexican trout, Truchas Mexicanas}, author = {Needham, P.R. and Gard, R.} } @article {5, title = {A New Trout from Central Mexico: Salmo chrysogaster, the Mexican Golden Trout}, journal = {Copeia}, volume = {1964}, year = {1964}, month = {1964/03/26/}, pages = {169 - 173}, abstract = {

In August 1952, a beautiful, golden-coloredtrout was collected in the Rio Verde near Guadalupe y Calvo in southwestern Chihuahua. This trout was described, but not named, by Needham and Gard (1959). We did not name it at that time because we had little information concerning the amount of variability found in western North American members of the genus Salmo throughout its entire range. Before this trout was named we wanted to be confident that its distinctive characters had a genetic basis and were not mainly phenotypic expressions of local environmental phenomena. The compilation of data by Needham and Behnke (unpublished) on more than 2,000 specimens of the genus Salmo from western North America, collected from virtually their entire native range, has demonstrated that, indeed, the Mexican golden trout is a distinct group and worthy of taxonomic recognition. Taxonomic methods used are essentially those listed in Hubbs and Lagler (1949) with the modifications noted in Needham and Gard (1959).

}, keywords = {Mexican golden trout, Mexican trout, Truchas Mexicanas}, url = {http://www.jstor.org/stable/1440847}, author = {Needham, Paul R. and Gard, Richard} }