Riqueza y abundancia relativa de mamíferos medianos y grandes en una localidad en la Reserva de la Biosfera Tehuacán-Cuicatlán, Oaxaca, México

THERYA, 2015, Vol. 6 (2): 435-448
DOI: 10.12933/therya-15-277, ISSN 2007-3364

Riqueza y abundancia relativa de mamíferos medianos y grandes en una localidad en la Reserva de la Biosfera Tehuacán-Cuicatlán, Oaxaca, México

Oscar Cruz-Jácome • Eva López-Tello •
Christian A. Delfín-Alfonso • Salvador Mandujano

Introduction: In Mexico, the state of Oaxaca is the second with higher mammalian richness. However, habitat loss and poaching have resulted in the decline and extinction of several species of flora and fauna. The present study focused on identifying the species richness and the relative abundance of medium and large mammals in the community of San Gabriel Casa Blanca, in the Biosphere Reserve Tehuacán-Cuicatlán. The work is important for the management and conservation of wildlife.
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Cascading impacts of anthropogenically driven habitat loss: deforestation, flooding, and possible lead poisoning in howler monkeys (Alouatta pigra)

ISSN: 0032-8332 (print version)
ISSN: 1610-7365 (electronic version)

Cascading impacts of anthropogenically driven habitat loss: deforestation, flooding, and possible lead poisoning in howler monkeys (Alouatta pigra)

Juan Carlos Serio-Silva •Eugenia J. Olguín •
Luis Garcia-Feria • Karla Tapia-Fierro •
Colin A. Chapman

Abstract
To construct informed conservation plans, researchers must go beyond understanding readily apparent threats such as habitat loss and bush-meat hunting. They must predict subtle and cascading effects of anthropogenic environmental modifications. This study considered a potential cascading effect of deforestation on the howler monkeys (Alouatta pigra) of Balancán, Mexico. Deforestation intensifies flooding. Thus, we predicted that increased flooding of the Usumacinta River, which creates large bodies of water that slowly evaporate, would produce increased lead content in the soils and plants, resulting in lead exposure in the howler monkeys. The average lead levels were 18.18 ± 6.76 ppm in the soils and 5.85 ± 4.37 ppm in the plants. However, the average lead content of the hair of 13 captured howler monkeys was 24.12 ± 5.84 ppm. The lead levels in the animals were correlated with 2 of 15 blood traits (lactate dehydrogenase and total bilirubin) previously documented to be associated with exposure to lead. Our research illustrates the urgent need to set reference values indicating when adverse impacts of high environmental lead levels occur, whether anthropogenic or natural, and the need to evaluate possible cascading effects of deforestation on primates.

Evaluation of fecal sex steroids in captive horned guan (Oreophasis derbianus, Aves: Cracidae)

Evaluación de esteroides sexuales fecales del pavón cornudo (Oreophasis derbianus, Aves: Cracidae) en cautiverio

Dr. Luis M. GARCÍA-FERIA,
Dra. Carolina VALDESPINO

Abstract
The measurement of sexual steroids over time allows evaluating the changes in reproductive function of individuals. We evaluate the profiles of fecal testosterone (T_f) and fecal estradiol (E_2f) of three males and four females of Oreophasis derbianus (Aves: Cracidae) in a breeding program. Sex steroids faecal samples were quantified by a chemoluminiscence immunoassay. There are not significant differences in the T_f concentrations between males (P = 0.894) and along the sampling time (P = 0.305), but there was a hormone pattern corresponding with monogamous mating system, even when the polygyny has been reported in this bird. One of the individuals had higher concentrations E_2f (34.09 ± 1 .08 ng/g) than the other two (6.83 ± 1 .38 and 7.98 ± 2.13 ng/g), suggesting a greater reproductive age, as has been previously reported that this hormone increases with senescence. The females did no show significant differences between them (P = 0.473) and along sampling time (P = 0.668). The evaluation of the concentrations of both steroids in the same individual and their ratio allowed defining that the hormonal activity corresponds to the traditionally assigned to each sex, where males show Tf concentrations larger than females and the opposite in the case of E_2f. The E_2f/T_f ratio is therefore greater in females. In captivity, estimate the gonadal activity to determine the success or reproductive failure, assess sexual maturity and fertility of wild animals, allow determining if an individual or group has the ability to reproduce and become part of a breeding program.

Disponible en Acta Zoológica Mexicana 31(1):1-9