Ecología trófica y evaluación del hábitat de Ovis canadensis mexicana, Ammotragus lervia y Odocoileus virginianus texanus en Coahuila, México

El borrego cimarrón y el venado cola blanca, son las especies cinegéticas más importantes del norte de México. Sin embargo, la presencia de especies exóticas como el borrego berberisco, representan una fuente de competencia por el alimento y hábitat. Por ello, el objetivo de este estudio, fue identificar la composición y diversidad del matorral desértico rosetófilo (Mdr) y matorral desértico micrófilo (Mdm), asociado a la presencia de estas tres especies. De igual manera, comparar la diversidad y selección del forraje. Por último, estimar la capacidad de carga de los tipos de vegetación en donde se distribuyen, en base a la producción estacional de biomasa. El presente, se realizó en la Unidad de Manejo para la Conservación de la Vida Silvestre Rancho San Juan, municipio de Monclova, Coahuila, México en el período octubre 2018 – agosto 2019. Para identificar la composición y diversidad del Mdr y Mdm, se utilizó el método de líneas de Canfield, de 25 m de longitud, ubicadas completamente al azar. La diversidad se estimó mediante los índices de Shannon, Simpson y Margalef. La composición de la dieta mediante la técnica microhistológica en muestras fecales, la selección del forraje con el índice de Ivlev, la producción de biomasa con el método de Adelaide y la capacidad de carga con el modelo propuesto por Holechek et al. (2001). El hábitat del borrego cimarrón, se compuso de 42 especies vegetales, representadas por 17 familias. Las arbóreas, arbustivas y pastos, fueron las especies más importantes. La diversidad, riqueza y dominancia de especies fueron mayores en otoño. El hábitat del borrego berberisco, registró 50 especies de plantas y 22 familias. Arbóreas y arbustivas, predominaron en las cuatro estaciones del año. La riqueza de especies en el hábitat del borrego berberisco, aumento a partir de otoño, pero se mantuvo constante la dominancia y diversidad. El hábitat del venado cola blanca, se caracterizó por matorral desértico micrófilo. Se registró un total de 42 especies de plantas, representadas por 21 familias. Las arbóreas y arbustivas predominaron en primavera y verano, y los pastos en otoño e invierno. La riqueza de plantas fue mayor en otoño. La diversidad y dominancia, disminuyeron de primavera a invierno. La dieta del borrego cimarrón se compuso de 49 especies, incluidas en 20 familias. La dieta anual se compuso de 38.21% arbóreas y arbustivas, 31.82% herbáceas, 15.83% pastos y 14.15%.suculentas. La dieta fue más diversa en invierno. El borrego cimarrón, consumió Acacia rigidula de manera proporcional a su disponibilidad, seleccionó Opuntia engelmannii y evito el consumo de Opuntia microdasys. La dieta del borrego berberisco se compuso de 64 especies y 21 familias. La dieta fue más diversa en otoño, 36.02% arbóreas y arbustivas, 29.83% herbáceas, 22.40% pastos y 11.76% suculentas, conformaron la dieta anual. El borrego berberisco consumió proporcionalmente Acacia rigidula, evito Guaiacum angustifolium, y seleccionó Opuntia engelmannii y Opuntia leptocaulis. Se identificaron 49 especies y 20 familias en la dieta del venado cola blanca. La dieta anual se conformó de 49.84% arbóreas y arbustivas, 18.38% suculentas, 16.02% herbáceas y 15.72% pastos. El venado cola blanca, consumió de manera proporcional Acacia rigidula y Cenchrus ciliaris, evitó Euphorbia antisyphilitica y seleccionó Opuntia engelmannii. La similitud en la composición de la dieta del borrego cimarrón, borrego berberisco y venado cola blanca fue alta. La capacidad de carga del Mdr se estimó en 3.76 ha/cimarrón/año y 3.50 ha/berberisco/año. Mientras que la del Mdm en 4.94 ha/venado/año. Debido a que la similitud en la composición y diversidad del hábitat, así como de la dieta fue alta, es recomendable que las tres especies continúen siendo manejadas de forma independiente. Además, los resultados indican que la densidad de borregos está por debajo de la capacidad de carga y la de venados ha sobrepasado la capacidad de carga del hábitat. Los resultados de este trabajo, pueden ser útiles en la implementación de mejoras de hábitat y en el manejo de estas tres especies. Abstract The bighorn sheep and the white-tailed deer are the most important game species in northern Mexico. However, the presence of exotic species such as the Barbary sheep represent a source of competition for food and habitat. Therefore, the objective of this study was to identify the composition and diversity of the rosetophilic desert scrub (Mdr) and microphilic desert scrub (Mdm), associated with the presence of these three species. Similarly, compare the diversity and selection of forage. Finally, estimate the carrying capacity of the types of vegetation where they are distributed, based on the seasonal production of biomass. This was carried out at the Wildlife Conservation Management Unit Rancho San Juan, municipality of Monclova, Coahuila, Mexico in the period October 2018 - August 2019. To identify the composition and diversity of Mdr and Mdm, it was used the method of Canfield lines, 25 m long, located completely at random. Diversity was estimated using the Shannon, Simpson and Margalef indices. The composition of the diet using the microhistological technique in fecal samples, the selection of the forage with the Ivlev index, the biomass production with the Adelaide method and the carrying capacity with the model proposed by Holechek et al. (2001). The habitat of the bighorn sheep was made up of 42 plant species, represented by 17 families. The arboreal, scrhubs and grasses were the most important species. The diversity, richness and dominance of species were higher in autumn. The habitat of the Barbary sheep registered 50 species of plants and 22 families. Arboreal and scrhubs, they predominated in the four seasons of the year. Species richness in the habitat of the Barbary sheep increased from autumn, but the dominance and diversity remained constant. The habitat of the white-tailed deer was characterized by microphyllous desert scrub. A total of 42 plant species were recorded, represented by 21 families. The arboreal and scrhubs predominated in spring and summer, and grasses in autumn and winter. The richness of plants was greater in autumn. Diversity and dominance decreased from spring to winter. The diet of the bighorn sheep was made up of 49 species, included in 20 families. The annual diet was composed of 38.21% arboreal and scrhubs, 31.82% herbaceous, 15.83% grasses and 14.15% succulent. The diet was more diverse in winter. The bighorn sheep consumed Acacia rigidula in proportion to its availability, selected Opuntia engelmannii and avoided the consumption of Opuntia microdasys. The diet of the Barbary sheep was made up of 64 species and 21 families. The diet was more diverse in autumn, 36.02% arboreal and scrhubs, 29.83% herbaceous, 22.40% grasses and 11.76% succulent, made up the annual diet. The Barbary sheep proportionally consumed Acacia rigidula, avoided Guaiacum angustifolium, and selected Opuntia engelmannii and Opuntia leptocaulis. 49 species and 20 families were identified in the diet of the white-tailed deer. The annual diet was made up of 49.84% arboreal and scrhubs, 18.38% succulent, 16.02% herbaceous and 15.72% grasses. The whitetailed deer proportionally consumed Acacia rigidula and Cenchrus ciliaris, avoided Euphorbia antisyphilitica and selected Opuntia engelmannii. The similarity in the composition of the diet of the bighorn sheep, Barbary sheep and white-tailed deer was high. The Mdr carrying capacity was estimated at 3.76 ha/bighorn sheep/ year and 3.50 ha/Barbary sheep/year. While that of the Mdm in 4.94 ha/deer/year. Because the similarity in the composition and diversity of the habitat, as well as the diet was high, it is recommended that the three species continue to be managed independently. In addition, the results indicate that the density of sheep is below the carrying capacity and that of deer has exceeded the carrying capacity of the habitat. The results of this work may be useful in the implementation of habitat improvements and in the management of these three species

Hábitos forrajeros de Ammotragus lervia (Pallas, 1777) (Artiodactyla: Bovidae) en matorral desértico rosetófilo de Coahuila, México

The barbary sheep (Ammotragus lervia Pallas, 1777) is an exotic herbivore considered an invasive species in northeastern Mexico, for which the effects of herbivory on native vegetation and competition with native ungulates are unknown. The objective of the study was to identify the composition and seasonal diversity of the diet of a population of A. lervia in the UMA Rancho San Juan, municipality of Monclova, Coahuila, Mexico. During the period October 2018-August 2019, lines were established where the fecal samples were collected, processed and classified, and a photographic catalog of plant cell structures of the plants present in the habitat was generated. Using the microhistological technique, the species of plants consumed were identified and classified by season: autumn (October 2018), winter (February 2019), spring (May 2019) and summer (August 2019) and biological form (shrubs, herbaceous, grasses and succulents). The diet was expressed in relative frequency based on the Fracker and Brischle table. The diversity of the diet was estimated with the Shannon index. In the diet of A. lervia, 64 species and 21 families were identified, being the families Poaceae (15), Fabaceae (9 spp.), Asteraceae (8 spp.) and Euphorbiaceae (7 spp.) the most representative. Likewise, Vachellia rigidula, Tiquilia canescens, Medicago sativa and Opuntia engelmannii together represented 46.49% of the diet. In the year, the diet was made up of 36% shrubby plants, 30% herbaceous, 22% grasses and 12% succulents. Shrubs predominated in spring (54.80%), herbaceous plants (46.39 and 37.90%, respectively) in summer and winter, and grasses (35.19%) in autumn. The diversity of the diet was H’ = 2.89 ± 0.13 species, higher than that reported in its natural habitat. The composition of the diet of A. lervia was similar to that reported for other wild herbivores of desert scrub in Mexico and the United States, this implies a condition of overlapping diet, but more studies on the diet of sympatric herbivores of northeastern Mexico are required.El borrego berberisco (Ammotragus lervia Pallas, 1777) es un herbívoro exótico considerado una especie invasora en el noreste de México del que no se conocen los efectos de la herbivoría sobre la vegetación nativa y la competencia con los ungulados nativos. El objetivo del estudio fue identificar la composición y diversidad estacional de la dieta de una población de A. lervia en la UMA Rancho San Juan, municipio de Monclova, Coahuila, México. Durante el periodo octubre 2018-agosto 2019, se establecieron líneas donde se recolectaron, procesaron y clasificaron las muestras fecales, y se generó un catálogo fotográfico de estructuras celulares vegetales de las plantas presentes en el hábitat. Mediante la técnica microhistológica se identificaron las especies de plantas consumidas y se clasificaron por estación: otoño (octubre 2018), invierno (febrero 2019), primavera (mayo 2019) y verano (agosto 2019), y forma biológica (arbustivas, herbáceas, pastos y suculentas). La dieta se expresó en frecuencia relativa con base en el cuadro de Fracker y Brischle. La diversidad de la dieta se estimó con el índice de Shannon. En la dieta de A. lervia se identificaron 64 especies y 21 familias, siendo las familias Poaceae (15), Fabaceae (9 spp.), Asteraceae (8 spp.) y Euphorbiaceae (7 spp.) las más representativas. Asimismo, Vachellia rigidula, Tiquilia canescens, Medicago sativa y Opuntia engelmannii, representaron en conjunto el 46.49 % de la dieta. En el año, la dieta se conformó de 36 % de plantas de porte arbustivo, 30 % herbáceas, 22 % pastos y 12 % suculentas. En primavera predominaron las arbustivas (54.80 %), en verano e invierno las herbáceas (46.39 y 37.90 %, respectivamente) y en otoño los pastos (35.19 %). La diversidad de la dieta fue H’ = 2.89 ± 0.13 especies, mayor a lo reportado en su hábitat natural. La composición de la dieta de A. lervia fue similar a lo reportado para otros herbívoros silvestres de matorrales desérticos en México y Estados Unidos, esto implica una condición de traslape de dieta, pero se requieren de más estudios sobre dieta de herbívoros simpátricos del noreste de México

Micro minerales en hígado de Ovis canadensis mexicana Merriam, y Odocoileus hemionus eremicus Mearns en Sonora, México

Introduction: The bighorn sheep (BC) and mule deer (VB) are the most important hunting species in northwestern Mexico and their populations may be affected by micro-minerals deficiencies. Objective: Was to determine concentrations of micro-minerals Fe, Cu, Zn, Se, Mn, Co and Cr in the liver as indicators of deficiencies/excesses in BC and BV. Materials and methods: The study was carried out at the UMA "Rancho Noche Buena", located in Hermosillo, Sonora, Mexico. Liver samples were taken from three BC and five BV. The micro-minerals were determined on an inductively coupled quadrupole plasma mass spectrometer (ICP-MS) and the analyzes were validated using a reference sample. Results: In BC the average contents of Fe, Cu, Zn, Se, Mn, and Cr were 114.8, 60.9, 63.8, 1.1, 2.6, and 0.15 mgkg-1 and in VB were of 183.9, 28.9, 44.6, 1.2, 2.6, and 0.17 mgkg-1, respectively, and are within the ranges considered as suitable for healthy animals. However, one BC and two BV had Cu deficiencies and 60% of the Zn BV. The Co contents in BC and VB were 14.6 and 12.3% lower as the adequate level. Conclusions: In BC (n=3) the Fe, Zn, Se and Mn contents were adequate and the Cu was partially adequate, in a BC was deficient. In VB, the Fe, Se and Mn contents indicate that there are no deficiencies. The Cu and Zn contents were partially adequate since 40 and 60% of the VB showed deficiencies. The Co was deficient in both species. Key words: Diagnosis; microelements; deficiencies, bighorn sheep, mule deer.Introducción: El borrego cimarrón (BC) y venado bura (VB) son las especies cinegéticas más importantes en el noroeste de México, sus poblaciones pueden ser afectadas por deficiencias de micro-minerales. Objetivo: Determinar la concentración de los micro-minerales Fe, Cu, Zn, Se, Mn, Co y Cr en hígado como indicadoras de deficiencias/excesos en BC y VB. Materiales y métodos: El estudio se realizó en la UMA “Rancho Noche Buena”, Hermosillo, Sonora, México. A tres BC y cinco VB se les tomaron muestras de hígado. Los micro-minerales se determinaron en espectrómetro de masas con plasma acoplado inductivamente cuadrupolo (ICP-MS) y los análisis se validaron utilizando una muestra de referencia. Resultados: En BC los contenidos promedio de Fe, Cu, Zn, Se, Mn, y Cr fueron de 114.8, 60.9, 63.8, 1.1, 2.6, y 0.15 mgkg-1, y en VB de 183.9, 28.9, 44.6, 1.2, 2.6, y 0.17 mgkg-1, respectivamente, los cuales son adecuados para animales sanos. Sin embargo, una muestra de BC y dos de VB presentaron deficiencias de Cu, y 60% de los VB de Zn. Asimismo, los contenidos de Co en BC y VB fueron 14.6 y 12.3% inferiores al nivel adecuado. Conclusiones: En BC (n=3) los contenidos de Fe, Zn, Se y Mn fueron adecuados y el Cu fue parcialmente adecuado, en una muestra fue deficiente. En VB, los contenidos de Fe, Se y Mn fueron adecuados. Los contenidos de Cu y Zn fueron parcialmente adecuados en el 40 y 60% de los VB, donde estuvieron en nivel de deficiencia. El Co fue deficiente en ambas especies. Palabras clave: Diagnóstico; microelementos; deficiencias, borrego cimarrón, venado bura

TRACKS INDEX AND VEGETATION CHARACTERISTICS OF THE HABITAT OF Mazama temama (KERR 1792) IMMERSED IN THE CAÑÓN DE RÍO BLANCO NATIONAL PARK, VERACRUZ, MEXICO

Background. The red temazate deer (Mazama temama, Artiodactyla: Cervidae) is a deer with ecological, cultural and economic importance, but its density and habitat characteristics in National Parks are unknown. Objective. To estimate the track index as an indirect measure of density and describe the vegetation characteristics of the habitat of M. temama in the town of Zapoapan, Parque Nacional Cañón del Río (PNCRB), Veracruz, Mexico. Methodology. During January to October 2021, eight transects were established to record tracks, phototraps were installed to determine their presence, and Canfield lines were used to describe the vegetation in areas with the presence of the species. Results. Twenty-three tracks of M. temama were recorded: nine tracks (39%), six excreta (26%), three foraging tracks (13%), three stalls (13%) and two photocaptures (8%), equivalent to an index tracks of 0.57 individuals/ha or 2.2 ha/individual, low density compared to other reports of the species. The habitat presented a richness of 19 species of plants, the shrubs being more abundant (36%) than the herbaceous and arboreal (represented by 32% each); the tree layer was dominant in terms of height and diameter. Implications. These results suggest that the habitat does not have sufficient diversity of resources to maintain a dense population of M. temama. Conclusion. The population density of M. temama in the PNCRB was low associated with a restricted carrying capacity in the study area, so actions must be taken towards the conservation and sustainable use of the population of this species

Composición de la dieta del venado cola blanca (Odocoileus virginianus texanus Mearns 1898) identificada en contenido ruminal en Coahuila, México: Dieta del venado cola blanca en Coahuila, México

Objective: Identify the diet of white-tailed deer in rumen samples at the UMA Rancho San Juan, municipality of Monclova, Coahuila, Mexico in the winter of 2019. Design/methodology/approach: To identify the composition of the diet of the white-tailed deer, the microhistological technique was used in samples of white-tailed deer rumen. For this, the capture of 50 females was carried out through 7 drop nets during the hunting season 2018-2019. Results: The deer's diet was made up of 39 plant species, represented by 18 families, the most common being Poaceae and Fabaceae, with 8 and 7 species, respectively. Prosopis glandulosa, Acacia rigidula, Setaria leucophylla and Leucophyllum frutescens, were the most frequent species in the diet. Of the total species, 17 have not been reported in the diet of O. v. texanus in northeast Mexico. The diet was made up of 37.73% shrubs, 23.44% grasses, 18.26% succulents, 17.21% trees and 3.35% herbaceous. Limitations on study/implications: The high percentage of grasses in the diet may indicate overgrazing by deer and low availability of preferred species. The present study aims to expand the knowledge about the diet of the white-tailed deer in northeast Mexico. Findings/conclusions: The study identified new species in the diet of the white-tailed deer in the northeast of Mexico and expands the knowledge on their feeding requirements, to implement pertinent habitat improvement measures. Keywords: Preferred species, Grasses, Microhistological Technique, Drop nets.Objetivo: Identificar la dieta del venado cola blanca en muestras de rumen en la UMA Rancho San Juan, municipio de Monclova, Coahuila, México en invierno de 2019. Diseño/metodología/aproximación: Para identificar la composición de la dieta del venado cola blanca se utilizó la técnica microhistológica en muestras de rumen de venado cola blanca. Para ello, se realizó la captura de 50 hembras a través de 7 redes de caída durante la época de cacería 2018-2019. Resultados: La dieta del venado se compusó de 39 especies de plantas, representadas por 18 familias, las más comunes fueron Poaceae y Fabaceae, con 8 y 7 especies, respectivamente. Prosopis glandulosa, Acacia rigidula, Setaria leucophylla y Leucophyllum frutescens, fueron las especies más frecuentes en la dieta. Del total de especies, 17 no se han reportado en la dieta de O. v. texanus en el noreste de México. La dieta se constituyó de 37.73% arbustivas, 23.44% gramíneas, 18.26% suculentas, 17.21% arbóreas y 3.35% herbáceas. Limitaciones del estudio/implicaciones: El alto porcentaje de gramíneas en la dieta puede indicar un sobrepastoreo por el venado y una baja disponibilidad de especies preferidas. El presente estudio pretende ampliar el conocimiento sobre la dieta del venado cola blanca en el noreste de México. Hallazgos/conclusiones: El estudio identificó nuevas especies en la dieta del venado cola blanca en el noreste de México y amplia el conocimiento sobre sus requerimientos alimentarios, para implementar medidas pertinentes de mejoramiento de hábitat

Diet and sexual segregation of desert bighorn sheep (Ovis canadensis mexicana Merriam) in Sonora, Mexico

Objective: To determine the diet of the desert bighorn sheep and to identify differences in its composition between sexes during the reproductive and sexual segregation periods. Design/methodology/approach: The study was carried in the UMA Rancho Noche Buena, Hermosillo, Sonora. The microhistological technique and a cell catalog of plants from the study area were used to identify plant species present in fecal samples of bighorn sheep. The relative frequency, the Shannon-Weaver diversity index and the Kulczynski similarity index were determined by sex and period (reproductive and segregation) Results: The diet of bighorn sheep included 40 species, being herbaceous (36.1 ±4.4 %) and grasses (26.8 ±8.9 %) the most common. The diet of males during the segregation period was mainly composed of grasses (36.2%) and female diet by herbaceous (30%) and grasses (29.8%). No differences were found in the diversity of the diet of males and females in the segregation period (H '= 1.0) and in general, their diets were very similar (80%). Limitations/implications: To collect a greater number of fecal samples by sex and period (reproductive and segregation) and to analyze the nutritional content of plants consumed by bighorn sheep. Findings/conclusions: In this study, the sexual segregation exhibited by the bighorn sheep in the Wildlife Management and Conservation Unit Rancho Noche Buena was not due to food preferences.Objective: To determine the diet of the desert bighorn sheep and to identify differencesin its composition between sexes during the reproductive and sexual segregation periods.Design/methodology/approach: The study was carried in the UMA Rancho NocheBuena, Hermosillo, Sonora. The microhistological technique and a cell catalog of plantsfrom the study area were used to identify plant species present in fecal samples ofbighorn sheep. The relative frequency, the Shannon-Weaver diversity index and theKulczynski similarity index were determined by sex and period (reproductive andsegregation)Results: The diet of bighorn sheep included 40 species, being herbaceous (36.1 ±4.4%) and grasses (26.8 ±8.9 %) the most common. The diet of males during thesegregation period was mainly composed of grasses (36.2%) and female diet byherbaceous (30%) and grasses (29.8%). No differences were found in the diversity ofthe diet of males and females in the segregation period (H '= 1.0) and in general, their diets were very similar (80%).Limitations/implications: To collect a greater number of fecal samples by sex andperiod (reproductive and segregation) and to analyze the nutritional content of plantsconsumed by bighorn sheep.Findings/conclusions: In this study, the sexual segregation exhibited by the bighornsheep in the Wildlife Management and Conservation Unit Rancho Noche Buena was notdue to food preferences

Forage diversity and selection in white-tailed deer (Odocoileus virginianus Texanus MEARNS) in coahuila, mexico: Forage selection of white-tailed deer in Coahuila

Objective: to identify the diversity and selection of their diet at UMA Rancho San Juan, Monclova, Coahuila, from October 2018 to August 2019. Design/methodology/approach: the composition of the white-tailed deer diet was identified with the microhistological technique. With the Canfield lines method, the availability of forage per season was calculated. The diversity of diet and forage, with the Shannon index and its relationship based on simple linear regression. The selection of the diet with the X2 test and the Ivlev index. Keywords: Canfield, availability, Ivlev, desert scrub, microhistological technique. Results: 49 species and 20 families were identified in the diet. Which is made up of 49.84% shrubs, 18.38% succulents, 16.02 % herbaceous and 15.72 % grasses. The deer selected Opuntia engelmannii, consumed Acacia rigidula and Cenchrus ciliaris proportionally to their availability, and consumed Acacia berlandieri, Jatropha dioica and Karwinskia humboldtiana below their availability. Limitations/implications: It is recommended to continue this line of research including aspects of nutritional quality of forage and variations in the diet between years of demonstration. It is recommended to favor the presence of herbaceous plants through habitat improvement techniques. Conclusions: the diversity of the diet was not related to that of the forage. When forage diversity is needed, increase grass intake.Objective: To identify diet diversity and selection among white-tailed deer (Odocoileus virginianus texanus Mearns) at UMA Rancho San Juan, Monclova, Coahuila, Mexico, from October 2018 to August 2019. Design/methodology/approach: The composition of the white-tailed deer’s diet was identified by applying the microhistological technique. The line interception method was used to estimate the seasonal availability of forage. Diet and forage diversity were established based on the Shannon index, while their relation was identified using a simple linear regression. Diet selection was determined using the chi-squared test and Ivlev’s electivity index. Results: We identified 49 species and 20 families in the diet, which comprised 49.84% shrubs, 18.38% succulents, 16.02% herbaceous plants, and 15.72% grasses. Deer selected Opuntia engelmannii, consumed Acacia rigidula and Cenchrus ciliaris in proportion to their availability, and consumed Acacia berlandieri, Jatropha dioica, and Karwinskia humboldtiana below their availability. Study Limitations/Implications: This line of research should be further pursued, including nutritional quality aspects of the forage and diet variations between sampling years. We also recommend fostering the presence of herbaceous plants through habitat improvement techniques. Conclusions: No relation was found between diet and forage diversity. When forage diversity decreased, grass intake increased