Browsing by Subject "Durango"
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Item Biodviersityof Mexican Trout (Teleostei: Salmonidae: Oncorhynchus): Recent findings, conservation concerns, and management recommendations(Universidad Autónoma de Nuevo León, Facultad de Ciencias Biológicas, Monterrey, Nuevo León, México, 2004-09) Mayden, Richard L.Until very recently the diversity of trout in Mexican rivers of the Sierra Madre Occidental has been very poorly understood and only the Rainbow Trout, Oncorhynchus mykiss, and the Mexican Golden Trout, 0. chrysogaster, have been recognized. Recent efforts in the last decade by a binational organization of scientists and laypersons interested in the diversity and conservation of Mexican trout, Truchas Mexicanus, have revea led considerable diversity within the river systems of the Pacific Slope south to the Rio Acaponeta . These trout forms are highly differentiated and distinctive, and are considered native to these high-elevation river systems in pine-dominated forests. The increased occurrence of trout growout facilities and hatcheries within the range of these native Oncorhynchus and the escapes from these facilities threaten the native trout diversity through both introgressive hybridization and through resource competition, end products already known to occur in other trout populations in the other areas of North America exposed to exotic hatchery trout. Other threats to the native and previously unknown trout biodiversity in Mexico include timber harvesting, some pollutions associated with these activities, and siltation of critical habitats. Recommendations are provided to aid in the safe management and protection of this diversity which center around the future use of sterile trout in growout facilities and the use of undisturbed buffer zones along streams. The divergence observed in forms of Mexican trout is equivalent to the levels of divergence found between currently recognized subspecies of trout in the Rainbow and Cutthroat trout groups. Upon review of the diversity and divergence known to exist in these groups and our current understanding of conceptualizations of species, it is argued that the recognition of subspecies within these highly diverse trout lineages is inconsistent with the natural evolutionary history of these groups. The long-term use of the Biological Species Concept for these species is argued as not only inappropriate but an inadequate and illogical characterization of diversity. The logical consequences of hanging on to this concept as the operational and theoretical framework of trout diversity would necessitate the synonymization of all Rainbow and Cutthroat trout taxa as subspecies because of the known propensity of these groups to demonstrate introgressive hybridzation in some areas. These subspecies are considered va lid evolutionary lineages that are demonstrate divergence at morphological, genetic, and ecological characters that are well known to many trout taxonomists and biologists. All of these therefore qualify as Evolutionary Species that are easily diagnosable under the Phylogenetic Species Concept and should be recognized as valid species.Item Cinemascape : Durango(2005-12) David, Erica Lynne; Stewart, Kathleen, 1953-Cinemascape: Durango is a portrait of “cinema” from the ethnographic perspective of Durango, a state in northern Mexico whose identity as Tierra del Cine is based on its history as a "location" for both Hollywood Westerns and the low-budget, Mexican action films known as churros. From the globally "marginal" vantage of Durango, it looks at how "cinema," as a mobile signifier transects and transforms seemingly disparate topics and spaces and becomes part of new cultural configurations and flows. These flows are both concretely economic, as in the transnational traffic in media products, and imaginary, as in changing senses of meaning and identity. It addresses cinema's manifestations and meanings in a variety of institutions and practices locally regarded as cinema-related. It includes chapters on everyday space and imagination; genre and "authoritarian" visual form; national and regional ideologies; and the specific careers and artistic production of two Durango filmmakers. Although production has diminished since the mid 1980s, due to the waning popularity of movie Westerns and the rise of video, "cinema" remains a powerful presence in Durango, palpable in discourses of nostalgia, hope and patrimony, as well as in material artifacts. It "exists" in bumper stickers that say "Durango, Tierra del Cine" and movie sets of Old West towns in various states of decay. One set has become a "real" town, with people living and working behind facades that say "Saloon" and "General Store." Another is now an amusement park. Others stand as decaying ghost towns. John Wayne had a ranch in Durango, and his image appears everywhere. The state tourist office is called "The Office of Tourism and Cinema." The particularity of Durango's cinematic terrain is evoked through a representational strategy of montage, organized by piling up "scenes" from everyday life, films and film history. Its aim is to show "cinema" as a point of connection within a broad social imaginary, working at different levels of specificity, and also "leaking." The dissertation is interdisciplinary in that it links culture to imagination (thus philosophy), media, art and literature (thus art history, cultural/film studies) and global capitalism (thus political economy, history, area studies).Item 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(Dirección de Publicaciones, Universidad Autónoma de Nuevo León, Facultad de Ciencias Biológicas, Monterrey, Nuevo León, México, 2007) Hendrickson, Dean A.; Neely, David A.; Mayden, Richard L.; Anderson, K.; Brooks, James E.; Camerana-Rosales, Faustino; Cutter, Ralph F.; Cutter, Lisa; De Los Santos Camarillo, Ana Belia; Ernsting, Guy W.; Espinosa-Pérez, Héctor; Findley, Lloyd T.; Garcia de León, Francisco J.; George, A. L.; Hatch, John; Kuhajda, Bernard R.; Mayden, Kyle E.; McNyset, Kristina M.; Nielsen, Jennifer L.; Pfeiffer, Frank W.; Propst, David L.; Ruiz-Campos, Gorgonio; St. Clair, E.; Tomelleri, Joseph R.; Varela-Romero, AlejandroThe 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.Item Fishes of the Río Fuerte, Sonora, Sinaloa and Chihuahua, México(Universidad Autónoma de Nuevo León, Facultad de Ciencias Biológicas, Monterrey, Nuevo León, México, 2002-11-10) Hendrickson, Dean A.; Varela Romero, AlejandroThe Rio Fuerte drains 33,835 km2.of the Sierra Madre Occidental of the Mexican states of Chihuahua, Sinaloa, Durango, and Sonora. Its tributaries pass through Barranca del Cobre (Copper Canyon) as they drop from headwaters as high as 2,808 m above sea level to the Mar de Cortes (Gulf of California). Its headwaters interdigitate closely with east-flowing tributaries of the Rio Conchos, an important tributary of the Rio Bravo (Grande), and interior drainages of Chihuahua and Durango, such as the Rio Nazas. The Fuerte shares its fish fauna with these neighboring drainages, and has no endemics. Northernmost tributaries are relatively arid, but southern tributaries drain sub-tropical areas with much higher rainfall. Dams and diversions now block movements of many marine fish species that used to move far upstream, and more are in construction or planned. Large river fish habitats at lower elevations have been converted almost entirely into canals and the natural mainstream channel now carries only minimal or highly modified discharges, often contaminated by agricultural runoff. At higher elevations, fish habitats have been severely impacted by logging and grazing. Logging development continues, recently expanding from traditional conifers to lower-elevation oaks. Exotic fishes have had, or surely will have, broad impacts on the native fauna through predation, competition and hybridization. Tilapias from Africa are widely established now, as are several centrarchids that will undoubtedly impact on the native cichlid (Cichlasoma beani), cyprinids, catostomids, poeciliids, and others. While not well studied taxonomically, the basin's native catfish, closely related to Ictalurus pricei, is now broadly hybridizing with introduced channel catfish (I. punctatus). At higher elevations, the beautiful native Mexican golden trout is very likely to hybridize with rainbow trout being widely introduced for fish culture. El Rio Fuerte drena 33,835 km2 de la Sierra Madre Occidental en los estados de Chihuahua, Sinaloa, Durango y Sonora. Sus tributarios fluyen a traves de la Barranca de! Cobre (Copper Canyon) y caen desde las cabeceras de 2,808 m sobre el nivel del mar hacia el Mar de Cortes (Gulf of California). Sus cabeceras interdigitan cercanamente con los tributarios de flujo este del Rio Conchos, un importante tributario del Rio Bravo (Grande) y drenajes interiores de Chihuahua y Durango como el Rio Nazas. El Fuerte comparte su fauna de peces con estos drenajes vecinos y no presenta endemicos. Los tributarios norteños son relativamente aridos, pero los tributarios sureños drenan areas subtropicales con mayor regimen de lluvias. Las presas y canales, que bloquean ahora el movimiento de muchas especies de peces marinos que lo usaban para remontar el rio, siguen en construcción y planeación. Los habitats de peces de rios grandes en bajas elevaciones han sido convertidos en canales y el canal principal natural ahora mantiene descargas minimas o altamente modificadas, frecuentemente contaminadas por desechos de la agricultura. A grandes elevaciones, los habitat de los peces han sido impactados severamente por la tala y el pastoreo. Los desarrollo madereros continuan y recientemente se han expandido de las tradicionales coniferas a los encinos de mas baja elevaci6n. Los peces exóticos tienen o seguramente tendran grandes impactos sobre los peces nativos a traves de la depredación, competencia e hibridación. Las tilapias de Africa estan ahora ampliamente establecidas al igual que varios centrarquidos, que indudablemente impactan sobre el ciclido nativo (Cich/asona beani), ciprinidos, catost6midos, pecilidos y otros. Aunque no esta bien estudiado taxonomicamente, el bagre nativo de la cuenca, cercanamente relacionado a Ictalurus pricei, esta ahora hibridizandose ampliamente con el bagre de canal introducido. A grandes elevaciones, la hermosa trucha dorada Mexicana nativa, es muy posible que hibridice con la trucha arcoiris, que ha sido ampliamente introducida como pez de cultivo.Item Species in the spotlight: Treasures of the Sierra Madre – Mexico’s little-known native trout diversity(International Union for the Conservation of Nature, 2020) Hendrickson, Dean A.Few individuals on our planet do not know what trout and salmon are. They are usually recognised as highly palatable, and often colourful species, and most who know them likely visualize cold, beautiful, pristine, free flowing, alpine or forest streams and rivers as their typical habitats. Many will also know of the remarkable migrations taken by some species, moving from their birth locations in rivers to oceans and then returning to their birthplaces to spawn and die. Some may recognise their importance as prized targets of anglers, particularly fly fishers, who spare no expenses to go after these trophies. Many others who might not be so familiar with the characteristics just mentioned may likely recognise species of this family as the tasty, and usually relatively costly fish found frozen or on ice in grocery stores and fish markets, or in cans, or smoked, or served in restaurants. Their flesh, often pink or rosy-coloured, is prized worldwide. There is no doubt that fishes in this family (Salmonidae) are well known in most of the developed and developing countries of the world and that some have become extremely economically and globally important commercial species that support large-scale recreational as well as wild commercial fisheries, and are massively produced by global aquaculture. At the same time many are also imperilled to some degree. Before this project, the Red List database contained 140 species of Salmonids. Here we’ll focus on the genus Oncorhynchus, commonly known as the Pacific salmons and trout, which prior to this project was represented in the Red List by six species. Then, setting aside the many “salmon” of this genus, we’ll focus only on trout, specifically those of a large and diverse lineage, best known for one species, the famous rainbow trout (O. mykiss). Originally known only from California and other Pacific drainages of the U.S., rainbow trout have long been a prized target of anglers, and the species has been bred in captivity for at least 150 years. High demand for it for both sport fisheries, as well as wild and captive protein production, resulted in it now being established on every continent. It has become not only one of the world’s most important recreational fishing species, but also one of the planet’s most widely cultured vertebrates. It is effectively global agriculture’s “fish version” of the chicken, with global aquaculture production of the species in 2014 reaching 812,940 metric tonnes valued at nearly 4 billion US$ (U.N. Food and Agriculture Organization (FAO) n.d.) That rainbow trout of global fishery and aquaculture fame is known to be one of about 10 closely related subspecies of what is called the “coastal rainbow” branch of the evolutionary tree of the genus. Most of those are from California, but two native Mexican taxa have long been recognised as part of this lineage, O. m. nelsoni (Nelson’s trout – recently reviewed by (Ruiz Campos, 2017)) of the northernmost mountains of Baja California, and O. chrysogaster (the Mexican golden trout – recently covered by multiple contributors (Ruiz-Luna & Garcia De León, 2016). Recent genetic studies (AbadíaCardoso et al., 2015) confirm those relationships and reveal, from specimens collected by the bi-national group of researchers known as Truchas Mexicanas (Hendrickson et al., 2003), that Mexico’s share of the diversity in this lineage is much greater. At least 10 more, still undescribed species of native trout reside in remote, rugged and isolated corners of the Sierra Madre Occidental extending as far south as the high mountains between Mazatlán and Ciudad Durango. Truchas Mexicanas’ fieldwork left no doubt that most share a need for conservation actions to help their often small and fragmented populations persist, and some are critically imperilled (Camarena-Rosales et al., 2006; Hendrickson et al., 2007; Hendrickson & Tomelleri 2019). While their formal descriptions have been delayed for various reasons, recent genetic validation of their distinctiveness, and clear need for recognition of the need for conservation actions on their behalf, led those studying them to petition the IUCN to add them to the Red List while their descriptions are being finalized. That petition was accepted and their assessments were completed as part of this project.Item (Vol. 06, 2003-12) A New Species of Galinsoga (Asteraceae: Millerieae: Galinsoginae) from Northwestern Mexico(2003-12) Panero, José L.Galinsoga crozierae from the state of Durango, northwest Mexico is described and its salient morphological features compared to those of other species in the genus.