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Search Results: 1 - 10 of 320382 matches for " Víctor Ayala-Pérez "
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Distribución espacio-temporal de aves acuáticas invernantes en la Ciénega de Tláhuac, planicie lacustre de Chalco, México Spatio-temporal distribution of wintering aquatic birds in the Ciénega de Tláhuac, Chalco lacustrine plain, Mexico
Víctor Ayala-Pérez,Nallely Arce,Roberto Carmona
Revista mexicana de biodiversidad , 2013,
Abstract: La avifauna acuática invernal de la ciénaga de Tláhuac fue estudiada de noviembre de 2006 a febrero de 2007; se identificaron 40 especies, 3 de las cuales corresponden a nuevos registros. El área fue utilizada por, al menos, 25 000 aves acuáticas; 5 fueron las especies dominantes: 3 anátidos (Anas clypeata, A. platyrhynchos diazi y Oxyura jamaicensis), 1 ave playera (Limnodromus scolopaceus) y 1 gallareta (Fulica americana). Sobresalió por su abundancia A. platyrhynchos diazi, subespecie endémica y amenazada, ya que los 2 200 individuos observados representan el 4% de la población total estimada. Las especies mejor representadas mostraron una utilización espacial diferencial, con 3 patrones: 1) especies con distribución uniforme (A. clypeata y F. americana), 2) las agrupadas en una sola porción del humedal (A.p. diazi y O. jamaicensis) y 3) aquella con afinidad por 2 porciones del humedal (L. scolopaceus). La ciénega de Tláhuac es un humedal importante para la avifauna de la región; en ella ocurren, durante el invierno, 6 especies protegidas por el gobierno mexicano; sin embargo, existen factores antrópicos que ponen en riesgo su integridad y que hacen necesarias acciones de protección y conservación. The winter waterbirds of the Ciénega de Tláhuac were studied from November 2006 to February 2007; a total of 40 species were observed, with 3 new records. The area was usedby al least 25 000 birds; 5 species were the dominant: 3 anatids (Anas clypeata, A. platyrhynchos diazi y Oxyura jamaicensis), 1 shorebird (Limnodromus scolopaceus) and 1 coot (Fulica americana). The abundance of A. platyrhynchos diazi, a threatened endemic subspecies, was remarkable because the 2 200 individuals observed represent 4% of its population.The best represented species showed a differential spatial use, with 3 patterns: 1) species with homogeneous use (A. clypeata y F. americana), 2) with affinity to a single portion of the wetland (A. p. diazi y O. jamaicensis), and 3) with affinity for both portions of the wetland (L. scolopaceus). The Ciénega de Tláhuac is an important wetland for birds in the region; during the winter 6 species protected by the Mexican Government occur there; however, there are human factors that threaten its integrity, so that protective and conservation actions are necessary.
New and noteworthy waterfowl records at artificial wetlands from Baja California Sur, Mexico
Carmona, Roberto;Ayala-Pérez, Víctor;Gutiérrez Aguilar, Antonio;
Revista mexicana de biodiversidad , 2011,
Abstract: we present 9 recent records of rare waterfowls in baja california sur, all of them in artificial wetlands: 3 freshwater sites and 1 concentration area for a saltworks. we present the first records of the ross's goose in the state. the remaining 8 species are: black-bellied whistling-duck (breeding), fulvous whistling-duck, greater white-fronted goose, snow goose, cackling goose, tundra swan, mallard and hooded merganser. to this list we added an historical compilation of the records of these species in artificial sites of the state. the artificial wetlands are no replacement for their natural counterparts, they are nevertheless an important part of the region's landscape mosaic. as the records of the present work exemplify, this man-made habitat increases the regional species richness, and should be considered as important areas that need to be protected.
New and noteworthy waterfowl records at artificial wetlands from Baja California Sur, Mexico Registros nuevos y sobresalientes de anátidos en humedales artificiales de Baja California Sur, México
Roberto Carmona,Víctor Ayala-Pérez,Antonio Gutiérrez Aguilar
Revista mexicana de biodiversidad , 2011,
Abstract: We present 9 recent records of rare waterfowls in Baja California Sur, all of them in artificial wetlands: 3 freshwater sites and 1 concentration area for a saltworks. We present the first records of the Ross's Goose in the state. The remaining 8 species are: Black-bellied Whistling-Duck (breeding), Fulvous Whistling-Duck, Greater White-fronted Goose, Snow Goose, Cackling Goose, Tundra Swan, Mallard and Hooded Merganser. To this list we added an historical compilation of the records of these species in artificial sites of the state. The artificial wetlands are no replacement for their natural counterparts, they are nevertheless an important part of the region's landscape mosaic. As the records of the present work exemplify, this man-made habitat increases the regional species richness, and should be considered as important areas that need to be protected. Presentamos registros recientes de 9 especies de anátidos raros en Baja California Sur, todos ellos realizados en humedales creados por el hombre: 3 sitios dulceacuícolas y 1 área de concentración para la producción de sal. Se incluyen los primeros registros del ganso de Ross (Chen rossii) para el estado. Las 8 especies restantes son: Dendrocygna autumnalis (anidación), D. bicolor, Anser albifrons, Chen caerulesens, Branta hutchinsii, Cygnus columbianus, Anas platyrhynchos y Lophodytes cucullatus. A la lista, agregamos una recopilación histórica de los registros de estas especies en humedales artificiales del estado. Aunque estos sitios no deben sustituir a sus contrapartes naturales, actualmente forman parte del mosaico paisajístico que ofrece la región; adicionalmente, incrementan la riqueza de especies de la región, por lo que es necesario brindarles protección.
Distribución, abundancia y parámetros poblacionales de la mojarra Diapterus rhombeus (Pisces: Gerreidae) en la Laguna de Términos, Campeche, México
Ayala-Pérez,Luis Amado; Gómez-Montes,Blanca Andrea; Ramos Miranda,Julia;
Revista de Biología Tropical , 2001,
Abstract: diapterus rhombeus dominates the nektonic community of terminos lagoon and is associated to zones with submerged vegetation, temperatures between 27 and 33°c and salinity between 25 and 36.5 ups. a total of 3 024 individuals were collected with a trawl net in 23 sites between september 1997 and september 1998. the length-weight model parameters are a=0.0098; b = 3.155 with a 96% correlation. the growth parameters are l = 20.4 cm, k = 0.74 and to= - 4.207 and the total mortality coefficient is 3.526. fish length is 2.5 - 18.0 cm with a mode of 7.5 cm. recruitment is continuous with a peak from may to august. the species uses several habitats of the lagoon mainly for feeding and growth, reproduction probably occurs in the adjacent continental shelf. movements between continental shelf and the estuarine system represent a continuous energy flow.
La comunidad de peces de la Laguna de Términos: estructura actual comparada
Amado Ayala-Pérez,Luis; Ramos Miranda,Julia; Flores Hernández,Domingo;
Revista de Biología Tropical , 2003,
Abstract: the structure of the fish community in terminos lagoon, campeche, is analyzed on the base the description of the abundance, distribution, length composition and identification of the dominant species. the results are discussed and compared with the published information. 437 trawl tows were made in 19 monthly collection in 23 sites between september 1997 to march 1999. a total of 25 588 individual with a total weight of 601.5 kg were grouped in 107 species, 76 gender and 37 families. the abundance of the fish community showed the following intervals in temporal scale: 0.395 to 0.895 ind/m2 ; 8.637 to 18.316 g/m2 and 18.358 to 34.837 g/ind. the shannon index oscillated between 1.875 and 3.995 and 4.94 and 7.88 respectively. 18 dominant species were identified. the most important species by its numerical abundance and appearance frequency is arius melanopus that represents to the 26.5% of the total catch followed by diapterus rhombeus with 18.9%. as dominant species, bairdiella chrysura, b. ronchus, archosargus rhomboidalis, eugerres plumieri, cynoscion arenarius and chaetodipterus faber, are fishing resources with local and regional value
Distribución, abundancia y parámetros poblacionales de la mojarra Diapterus rhombeus (Pisces: Gerreidae) en la Laguna de Términos, Campeche, México
Luis Amado Ayala-Pérez,Blanca Andrea Gómez-Montes,Julia Ramos Miranda
Revista de Biología Tropical , 2001,
Abstract: Diapterus rhombeus es una especie dominante dentro de la comunidad nectónica de la Laguna de Términos y se encuentra asociada a zonas con vegetación sumergida, con temperaturas entre 27 y 33°C y salinidad entre 25 y 36.5 UPS. Un total de 3024 individuos fueron recolectados con una red de arrastre en 23 sitios entre septiembre de 1997 y septiembre de 1998. Los parámetros del modelo Talla-Peso son a=0.0098; b=3.155 con una correlación del 96%. Los parámetros de crecimiento son L = 20.4cm, k= 0.74 y t o= -4.207 con un coeficiente de mortalidad total de 3.526. La población está representada por organismos con tallas entre 2.5 y 18.0 cm con una moda de 7.5 cm. El reclutamiento es continuo con un marcado pulso entre mayo y agosto. La especie utiliza distintos hábitat dentro de la Laguna de Términos principalmente para fines de alimentación y crecimiento y es probable que la maduración y reproducción se desarrollen en la plataforma continental adyacente. Estos movimientos de la especie se traducen en un continuo flujo de energía entre ambos sistemas. Diapterus rhombeus dominates the nektonic community of Terminos Lagoon and is associated to zones with submerged vegetation, temperatures between 27 and 33°C and salinity between 25 and 36.5 UPS. A total of 3 024 individuals were collected with a trawl net in 23 sites between September 1997 and September 1998. The length-weight model parameters are a=0.0098; b = 3.155 with a 96% correlation. The growth parameters are L = 20.4 cm, k = 0.74 and t o= - 4.207 and the total mortality coefficient is 3.526. Fish length is 2.5 - 18.0 cm with a mode of 7.5 cm. Recruitment is continuous with a peak from May to August. The species uses several habitats of the lagoon mainly for feeding and growth, reproduction probably occurs in the adjacent continental shelf. Movements between continental shelf and the estuarine system represent a continuous energy flow.
La comunidad de peces de la Laguna de Términos: estructura actual comparada
Luis Amado Ayala-Pérez,Julia Ramos Miranda,Domingo Flores Hernández
Revista de Biología Tropical , 2003,
Abstract: Se presentan los resultados de investigación sobre la ecología de la comunidad de peces de la Laguna de Términos. Se describe la estructura y se discute de manera comparada con la información publicada. Se realizaron 19 campa as mensuales de campo en 23 sitios de muestreo durante el periodo de septiembre de 1997 a marzo de 1999. Se identificaron 107 especies de peces que se agruparon en 76 géneros y 37 familias. Se capturaron 25588 organismos con un peso total de 601.5 kg. La abundancia de la comunidad en escala temporal osciló de 0.395 a 0.895 ind/m2 ; 8.638 a 18.316 g/m2 y 18.358 a 34.837 g/ind. La diversidad de la comunidad, estimada por el índice de Shannon y Weaver osciló entre 1.875 y 3.995. El valor de los índices de equitatividad y riqueza de especies presentaron una variación entre 0.519 y 0.993 y 4.94 y 7.88 respectivamente. Se identificaron 18 especies dominantes con base en el análisis de los valores de número de individuos, peso y porcentaje de aparición. La especie más importante tanto por su abundancia numérica como por su frecuencia de aparición es Arius melanopus que representa el 26.5% de la captura total seguida de Diapterus rhombeus con el 18.9%. También como especies dominantes cabe destacar la presencia de aquellas de interés pesquero tanto local como regional y son Bairdiella chrysura, B. ronchus, Archosargus rhomboidalis, Eugerres plumieri, Cynoscion arenarius y Chaetodipterus faber The structure of the fish community in Terminos Lagoon, Campeche, is analyzed on the base the description of the abundance, distribution, length composition and identification of the dominant species. The results are discussed and compared with the published information. 437 trawl tows were made in 19 monthly collection in 23 sites between September 1997 to March 1999. A total of 25 588 individual with a total weight of 601.5 kg were grouped in 107 species, 76 gender and 37 families. The abundance of the fish community showed the following intervals in temporal scale: 0.395 to 0.895 ind/m2 ; 8.637 to 18.316 g/m2 and 18.358 to 34.837 g/ind. The Shannon index oscillated between 1.875 and 3.995 and 4.94 and 7.88 respectively. 18 dominant species were identified. The most important species by its numerical abundance and appearance frequency is Arius melanopus that represents to the 26.5% of the total catch followed by Diapterus rhombeus with 18.9%. As dominant species, Bairdiella chrysura, B. ronchus, Archosargus rhomboidalis, Eugerres plumieri, Cynoscion arenarius and Chaetodipterus faber, are fishing resources with local and regional value
Growth, mortality, maturity, and recruitment of the star drum (Stellifer lanceolatus) in the southern Gulf of Mexico
Ramos-Miranda, J;Bejarano-Hau, K;Flores-Hernández, D;Ayala-Pérez, LA;
Ciencias marinas , 2009,
Abstract: the star drum stellifer lanceolatus (holbrook 1855) is a dominant species along the western part of the campeche coastline, southern gulf of mexico, and it is regularly caught as bycatch in the seabob shrimp (xiphopenaeus kroyeri) fishery. it is not commercially important but plays an important role in the transfer of energy through the ecosystem. the spatial and temporal abundance of the species allowed the identification of clear preferences in spatial size distribution. the von bertalanffy growth model showed seasonal fluctuations and was defined by the following parameters: l∞ = 18.5 cm, k = 0.4 yr-1, t0 = -0.083 yr-1, c = 0.63, wp = 0.8, and rn = 0.254. the parameters of the length-weight relationship were a = 0.52 x 10-6 (condition factor) and b = 3.16, indicating isometric growth (t0.05(2), p > 0.05) with a correlation coefficient of 0.97. the monthly condition factor was lower from february to august and increased from september to november, associated with the maturity stage. size and age at first maturity were 9.2 cm and 1.64 yr, respectively. total mortality rate was 1.68 yr-1. recruitment was continuous with a main pulse from march to july. the life cycle of s. lanceolatus was determined, with reproduction occurring in the coastal zone, juveniles (<9.2 cm) then moving closer to shore until attaining maturity, and returning as adults to deeper areas to reproduce. further studies are necessary to relate its life cycle to the environment.
Estructura de la comunidad de peces en el sistema Candelaria-Panlau, Campeche, México
Ayala-Pérez,Luis Amado; Avilés-Alatriste,Obed Agustín; Rojas-Galaviz,José Luis;
Revista de Biología Tropical , 1998,
Abstract: the environmental and ecological patterns of the fish community in candelaria-panlau system (mexico) are described. parameters of the water temperature, salinity and transparency, and density, biomass and diversity of the fish community were analyzed. between april 1993 and april 1994 five stations were sampled monthly. the fish community had 50 species (7 926 individuals, 144.7 kg of weight). the abundance and diversity values for the fish community were: 0.09 ind/m2 ; 1.61 g/m2; 18.25 g/ind ; h'n = 1.879; j = 0.475 and d = 5.681. the species with ecological dominance were: cathorops melanopus, diapterus rhombeus, anchoa mitchilli, sphoeroides testudineus, bairdiella chrysura, b. ronchus, cynoscion arenarius, and c. nebulosus. the matrixes of the environmental parameters and of fish abundance, were tested with a factor analysis (principal components extraction method); its graphical representation confirms the dominant species and indicates that salinity, station number five and february are the components that characterize the system and the fish community.
Estructura de la comunidad de peces en el sistema Candelaria-Panlau, Campeche, México
Luis Amado Ayala-Pérez,Obed Agustín Avilés-Alatriste,José Luis Rojas-Galaviz
Revista de Biología Tropical , 1998,
Abstract: Se describe el comportamiento de los parámetros de temperatura, salinidad, transparencia del agua y temperatura ambiente, y de la abundancia y diversidad de la comunidad del peces del sistema Candelaria-Panlau en escalas temporal y espacial. Los trabajos de campo se realizaron de manera mensual en cinco estaciones entre abril de 1993 y abril de 1994. La comunidad de peces quedó representada por 50 especies con 7 926 organismos y 144.7 kg de peso. Los valores de abundancia y diversidad de la comunidad fueron: 0.09 ind/m2, 1.61 g/m2 18.25 g/ind, H’n = 1.879, J = 0.475 y D = 5.681. Las especies con dominio ecológico fueron: Cathorops melanopus, Diapterus rhombeus, Anchoa mitchilli, Sphoeroides testudineus, Bairdiella chrysura, B. ronchus, Cynoscion arenarius, y C. nebulosus, que en conjunto representan el 90.9 % en número y el 78.9 % en peso de la captura total. Las matrices de valores de los parámetros ambientales y de abundancia numérica de la comunidad de peces, fueron sometidas a un análisis de factores con el método de extracción de componentes principales, su representación gráfica confirma la definición de especies dominantes y demuestra que la salinidad, estación cinco y mes de febrero son los componentes que caracterizan al sistema y a la comunidad de peces. The environmental and ecological patterns of the fish community in Candelaria-Panlau system (Mexico) are described. Parameters of the water temperature, salinity and transparency, and density, biomass and diversity of the fish community were analyzed. Between April 1993 and April 1994 five stations were sampled monthly. The fish community had 50 species (7 926 individuals, 144.7 kg of weight). The abundance and diversity values for the fish community were: 0.09 ind/m2 ; 1.61 g/m2; 18.25 g/ind ; H'n = 1.879; J = 0.475 and D = 5.681. The species with ecological dominance were: Cathorops melanopus, Diapterus rhombeus, Anchoa mitchilli, Sphoeroides testudineus, Bairdiella chrysura, B. ronchus, Cynoscion arenarius, and C. nebulosus. The matrixes of the environmental parameters and of fish abundance, were tested with a factor analysis (principal components extraction method); its graphical representation confirms the dominant species and indicates that salinity, station number five and February are the components that characterize the system and the fish community.
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