Reassessment of the distribution and population size of Spizella wortheni

Summary Information deficit constrains our capacity to assess the status of threatened species in regional and global contexts. In this study of the endangered Worthen’s Sparrow Spizella wortheni, we first review its current and potential distribution using the species distribution software, Maxent. An initial basic model was constructed using historical records, and used to guide a subsequent search for additional populations in summer 2013. Using the information gathered from our survey, we built a second, breeding model, to update the current and potential species distribution. Population size was estimated using line transects of variable length to count singing males and calculate densities per 10 ha. We found 10 new small reproductive populations dispersed south of the established core area, increasing the extent of occurrence of the species from 25 km2 to almost 17,000 km2. Suitable habitat across the species’ range was more than threefold higher in the breeding compared with the basic model. We counted 316 males, with a mean density of four individuals per 10 ha. Our results demonstrate that conservation assessment based on limited records can exaggerate the vulnerability of species, and confirm that the Worthen’s Sparrow population and geographic distribution range are larger than previously determined, indicating that the Red List status of this species should be reconsidered. The use of niche models was successful in enhancing species information data quantity (e.g. range extensions) and quality (e.g. more precise habitat requirements), facilitating improved understanding of needs and conservation status in the wild

The use of Genomics in scientific research and management of wildlife in Mexico

"México alberga una diversidad biológica excepcional que lo coloca entre los principales países megadiversos, pues posee tres de las 34 ecorregiones del mundo y zonas consideradas áreas silvestres a nivel mundial, como los desiertos de Chihuahua, Sonora y California; su importancia radica en que reúne alrededor de 70 % de su hábitat original en buenas condiciones y una densidad poblacional humana menor a 5 habitantes km-2. El uso de la genómica como herramienta en la investigación científica en este país tuvo sus inicios a finales de 1930 con trabajos encaminados al mejoramiento genético de cultivos comerciales y a entender los fundamentos ecológicos de la variación genética en Drosophila pseudooscura, pero hasta los años 80 y 90 comenzó el estudio de la flora y la fauna bajo esa perspectiva. Sin embargo, a pesar del potencial que las técnicas genómicas ofrecen para mejorar el desarrollo de estrategias y políticas de gestión que aseguren la producción de alimentos y la preservación de especies, no han sido extensamente utilizadas. Se presenta una revisión de las áreas del conocimiento en la vida silvestre en las que la genómica ha sido incorporada para abordar poblaciones naturales y se discuten los aspectos en los que puede incidir dentro del manejo y conservación de taxa de importancia biológica y comercial.""Mexico has a unique biodiversity that places it within the list of megadiverse countries; it has three of the 34 ecoregions of the world and sites that are considered wilderness areas worldwide. The use of Genomics as a tool for research in Mexico began in the late 1930s with work aimed at the genetic improvement of commercial crops and to understand the ecological foundations of the genetic variation in Drosohpila pseudooscura, however, it wasn't until the decades of 1980-1990s that these tools were used for the study of natural populations of flora and fauna with purposes of conservation and management. Nonetheless, the potential that genomic tools have to improve the strategies and policies of management to ensure food production and conservation of wildlife in Mexico, these have not been widely applied. In this paper the areas of knowledge in wildlife where genomics have been applied in the study of natural populations of flora and fauna in Mexico were reviewed, and the practical applications of genomics for management and conservation of species of biological and commercial concern were discussed.

Producción de hojarasca y retorno de nutrientes vía foliar en un matorral desértico micrófilo en el Noreste de México = Litterfall production and nutrient returns through leaves in a microphyllous desert scrubland, northeastern Mexico

La caída de hojarasca y el contenido de macro (Ca, N, P, Mg y K) y microminerales (Fe, Mn y Zn) de las hojas se compararon en dos sitios durante 12 meses (septiembre 2008-agosto 2009). El sitio 1 se ubicó en la comunidad El Llano de La Soledad, Galeana, Nuevo León (1,863 m) y el sitio 2 en la comunidad San José del Alamito, Satillo, Coahuila (1,895 m). En cada sitio se colocaron, aleatoriamente, 10 canastas (1 m2) para la captura de hojarasca. La caída anual de hojarasca en el sitio 2 fue mayor (407 g·m-2·año-1) que en el sitio 1 (162 g·m-2·año-1). Las hojas representaron el 47.7 y 53.2 % en el sitio 1 y 2, respectivamente, seguido de ramas (24.6 y 20.3 %), estructuras reproductivas (21.3 y 20.2 %) y otros (4.3 y 7.6 %). La deposición de macro y microminerales fue mayor en el sitio 2 que en el sitio 1. Las diferencias espaciales y temporales, en la cantidad de hojarasca y el retorno de minerales, pudieron estar relacionadas con las temperaturas extremas, composición de la vegetación y propiedades químicas del suelo. ABSTRACT Litterfall and macro (Ca, N, P, Mg and K) and microminerals (Fe, Mn and Zn) components of the leaves were compared in two sites for 12 months (September 2008-Agust 2009). Site 1 was located in El Llano de La Soledad, Galeana, Nuevo León, Mexico (1863 m) and site 2 in San José del Alamito, Saltillo, Coahuila, Mexico (1895 m). A total of 10 litter traps (1 m2) were randomly located at each site to collect litterfall. The annual litterfall at site 2 was higher (407 g·m-2·year-1) than at site 1 (162 g·m-2·year-1). Leaves (47.7 and 53.2 %: site 1 and site 2, respectively) constituted the highest component, followed by branches (24.6 and 20.3 %), reproductive structures (21.3 and 20.2 %) and others (4.3 and 7.6 %). The deposition of macro and microminerals was higher at site 2 than at site 1. The spatio-temporal differences in litterfall and mineral return might have been related to the extreme temperatures, plant species composition and chemical soil properties

Medicinal plants in the southern region of the State of Nuevo León, México

Background: Although the flora of the State of Nuevo León is well known, there are few records of ethnobotancial information. An ethnobotanical study was undertaken in order to know the medicinal plants used by people living at the scrublands and oak-pine forest areas in the southern Nuevo León. Collection of plants specimens and interviews were carried out among the people of the municipalities of Aramberri, Galeana, and Zaragoza. Since former studies in the region are scarce, the aim of this work was to record the medicinal species and their uses in the scrublands and oak-pine forest areas, of southern Nuevo León, Mexico, and also to know if there are differences in the number of species and number of uses knowledge by people. Methods: Field work was carried out over a 2 years period; useful plants were collected and a total of 105 people from 46 different villages were interviewed. A database was compiled using data collected by means of semi structured interviews. The data were analyzed by means of non-parametric statistics, using goodness-of-fit test (Chi-squared) (number of species known by people of each municipality, number of uses known by people of each municipality), Chi-squared modified to incorporate the Yates Correction (number of species known by people living at scrublands and oak-pine forest); the Kruskall-Wallis test (number of species known by women and men of the three municipalities), and the Spearman’s rank correlation coefficient (age and number of species known, and age and number of uses). Results: A total of 163 medicinal plant species were recorded in the study area, comprising 108 wild and 55 cultivated plants. A total of 117 species were recorded in the oak-pine forest, and 111 in the scrublands area, a total of 68 were recorded in both areas; 68 medicinal species are used in all three municipalities, 40 wild and 28 cultivated. We documented 235 different medicinal uses. The most common plant parts used for medicinal purposes were found to be leaves (123 species), stems (55), fruits (28), roots (17), and bark (14). No differences were noted in the number of medicinal plant species identified among people, but differences were significant in their knowledge with respect to the number of uses among people of the three municipalities studied; people from both, scrublands and oak-pine forest know similar number of species and number of uses. Men and women of the three different municipalities knew statistically the same number of species and number of uses. There was no correlation between resident’s age and number of species known and resident’s age and number of uses either in Galeana or in Aramberri, but, there was high correlation among these variables in Zaragoza Conclusion: In southern Nuevo León people use at least 5% of the total State flora as medicinal plants, and most of these species are included in few plant families. Most of medicinal species are wild and indigenous to the region. The two most important major plant communities, scrublands and oak-pine forest provide almost the same number of medicinal species. A third of the medicinal flora recorded are used in all three municipalities, most of them are wild. Leaves, stems and fruits are the plant parts most commonly used for healing, and boiling is the most common method used for this purpose. Men and women from the three municipalities are familiar with nearly the same number of species; however, their knowledge of the number of uses varies significantly. In Galeana and Aramberri there was no correlation between a person’s age and number of species recognized, however, in Zaragoza, there existed a high correlation between these two factors

Chemical composition and digestion of shurbs browsed by white-tailed deer (odocoileus virginianus texanus)

The aim of the study was to determine, seasonally, the nutritional value of the native shrubs: Acacia amentacea, Castela erecta, Celtis pallida, Croton cortesianus, Forestiera angustifolia, Karwinskia humboldtiana, Lantana macropoda, Leucophyllum frutescens, Prosopis laevigata, Syderoxylon celastrinum and Zanthoxylum fagara. Leave samples were collected seasonally during 2 years from Summer 2004 to Spring 2006 in three county sites: China, Linares and Los Ramones in the state Nuevo Leon, Mexico and evaluated for the content of their Crude Protein (CP), Neutral Detergent Fiber (NDF) and Acid Detergent Lignin (ADL). Dry Matter Digestibility (DMD) was also estimated. The CP content (range of total means = 13-22% dry matter) in most plants significantly varied among sites and seasons and between years. The same pattern occurred for NDF (40-55), ADL (8-22) and DMD (48-73). Celtis pallida had the highest nutritional value. However, due to their high CP and DMD and low NDF and ADL all studied plants in all sites, most seasons and years may be considered as good food sources for white-tailed deer

Macro Mineral Content in Five Shrubs Browsed by White-Tailed Deer (Odocoileus virginianus), Northeastern Mexico

The Ca, K, Mg, Na and P contents were determined, seasonally during 2 consecutive years in leaves of native browse plants such as Castela erecta Turp sp. Texana (Torr & A. Gray) Cronquist (Simaroubaceae), Celtis pallida Torr. (Ulmaceae), Forestiera angustifolia Torr. (Oleaceae), Lantana macropoda Torr. (Verbenaceae) and Zanthoxylum fagara (L.) Sarg (Rutaceae) that were collected from August 2004 to May 2006 in a semiarid and subtropical area of the State of Nuevo Leon, Mexico at three county (Los Ramones, China and Linares) sites which are grouped under a similar climatic pattern. Mineral contents were measured using an atomic absorption spectrophotometer with exception of P content that was estimated using a colorimeter. All minerals in all species were significantly different among years, sites and seasons and interactions were also significant. In general, plants at Linares site which historically registered the highest rainfall had higher mineral content followed by Los Ramones and China. Moreover, during the 2nd year, all plants species showed higher mineral content than the 1st year. Furthermore, during the Summer session, all plants species had higher mineral content followed by Autumn, Winter and Spring. Regardless of spatio-temporal differences, all plant species had suitable levels of Ca, Mg and K to satisfy range domestic and wild ruminant requirements. In contrast, P and Na contents showed marginal inadequacies in some seasons throughout the year. Seasonal variations in minerals could be associated to climatic conditions like excessive irradiance levels during Summer and extreme low temperatures in Winter and rainfall events

La genómica en la investigación científica y en la gestión de la vida silvestre en México

México alberga una diversidad biológica excepcional que lo coloca entre los principales países megadiversos, pues posee tres de las 34 ecorregiones del mundo y zonas consideradas áreas silvestres a nivel mundial, como los desiertos de Chihuahua, Sonora y California; su importancia radica en que reune alrededor de 70 % de su hábitat original en buenas condiciones y una densidad poblacional humana menor a 5 habitantes km-2. El uso de la genómica como herramienta en la investigación científica en este país tuvo sus inicios a finales de 1930 con trabajos encaminados al mejoramiento genético de cultivos comerciales y a entender los fundamentos ecológicos de la variación genética en Drosophila pseudooscura, pero hasta los años 80 y 90 comenzó el estudio de la flora y la fauna bajo esa perspectiva. Sin embargo, a pesar del potencial que las técnicas genómicas ofrecen para mejorar el desarrollo de estrategias y políticas de gestión que aseguren la producción de alimentos y la preservación de especies, no han sido extensamente utilizadas. Se presenta una revisión de las áreas del conocimiento en la vida silvestre en las que la genómica ha sido incorporada para abordar poblaciones naturales y se discuten los aspectos en los que puede incidir dentro del manejo y conservación de taxa de importancia biológica y comercial

Clasificación de los pastizales halófilos del noreste de México asociados con perrito de las praderas (Cynomys mexicanus): diversidad y endemismo de especies Classification, diversity and plant endemism in the halophytic grasslands in northeastern Mexico associated to prairie dogs (Cynomys mexicanus)

Se clasifican 39 áreas de pastizal halófilo del noreste de México con el objetivo de cuantificar la diversidad, superficie e impacto debido al manejo antrópico al que están sometidas. La cobertura, densidad, frecuencia y diversidad de las especies se cuantificaron al menos en 200 cuadrantes de 1 m² en cada área de pastizal. La información se analizó mediante índices de similitud de Sörensen, coeficientes de correlación cofenético, análisis de conglomerados, índice de diversidad de Shannon-Wiener y pruebas de Kruskall-Wallis. Se registraron 53 familias, 174 géneros y 284 especies de plantas vasculares; 17 especies son endémicas en estos pastizales. Las áreas de pastizal con manejo pastoreo-agricultura poseen mayor diversidad de especies, mayor abundancia de malezas y menor abundancia de endémicas. Las áreas con manejo de pastoreo, poseen menor diversidad de especies, menor abundancia de malezas y mayor densidad de especies endémicas. La agricultura mecanizada es la principal causa de pérdida de pastizal halófilo y del hábitat del perro de las praderas. La pérdida total de pastizal halófilo en el noreste de México fue de 71.5% de su superficie hasta el año 2007.The objective of this study was to classify the vegetation, to quantify the plant diversity, currently occupied surface and the impact in vegetal diversity in the 39 halophytic grassland areas in northeastern Mexico due to management activities. Canopy cover, density, frequency, and species diversity was quantified in at least 200 1 m² quadrats in each of the 39 grassland areas. Information and field data were analyzed by means of Sörensen Similarity Index, cophenetic correlation coefficient, cluster analysis, Shannon-Wiener diversity index, product moment correlation coefficient, and Kruskall-Wallis test. Grazing-agriculture areas have the highest plant diversity, higher weeds density, lower endemic species abundance. Grazing areas have lower plant diversity, lower weed abundance and higher endemic plants abundance. Mechanized agriculture is the main cause of loss of halophytic grasslands and prairie dog habitat. In this study 53 families, 174 genera and 284 species of vascular plants were recorded. Total lost of halophytic grassland in northeastern Mexico is about 75% of its surface until the year 2007