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La urbanización modifica la abundancia y tipo de materiales naturales usados por aves en la nidación. La incorporación de materiales antrópicos (de uso humano) al nido es riesgosa para los polluelos y el éxito reproductivo de las poblaciones. En este trabajo se evalúa la composición de nidos de aves silvestres en parques urbanos y periurbanos de Xalapa y Coatepec, Veracruz, México. Durante marzo- julio 2017, se eligieron dos parques urbanos y tres periurbanos en Xalapa y uno urbano en Coatepec, donde se colectaron en general diez nidos inactivos por mes en cada parque. Los nidos fueron secados y los materiales separados y pesados en una balanza analítica considerando cuatro criterios: material vegetal (MVE), material de origen animal (MOA), material de sustrato (MSU) y antrópico (MAN). Por cada tipo de material se obtuvo el porcentaje relativo. Un ANOVA con interacciones de dos vías (tipo de material y tipo de parque) fue utilizado para establecer diferencias en los porcentajes relativos transformados a raíz cuadrada del arcoseno. Un ACP mostró grupos de los materiales usados. Sólo la composición de nidos fue diferente entre tipos de materiales (F3,1312 = 2637.26, P < 0.001) siendo el MVE y MSU mayormente representados 1.28 ± 0.016 y 0.24 ± 0.016 (media del arcoseno ± EE). Dos componentes explicaron el 93.2% de la variación. El CP1 (2.2203 eigenvalor) se relacionó con el peso del MOA y el MAN, y el CP2 (1.5077 eigenvalor) con el MVE. Se concluye que las aves usaron mayor MVE en sus nidos con fines estructurales y de revestimiento, independientemente del ambiente urbano o periurbano.

Although the transformation of landscapes by human activity can negatively affect the populations of several bat species, other species may benefit from these transformations. One of such species is the vampire bat, Desmodus rotundus, which can often be found in landscapes dominated by livestock activities. Furthermore, there are certain structural landscape characteristics that could be positively influencing the abundance of the vampire bat. To assess this possibility, eight sampling sites in northeastern Yucatan, Mexico were monitored from June 2010 to February 2012. Four sites were located in forest fragments amongst a highly fragmented landscape dominated by pastures dedicated to livestock activities, and four sites were located within continuous tropical semideciduous forest with almost no fragmentation. Forest fragmentation was characterized around the sampling sites within a 2.5 km radius using SPOT images from 2010, and five landscape variables were calculated using FRAGSTATS. The results showed that landscape heterogeneity and an agricultural aggregation index both had a significant effect on the abundance of the vampire bat. Our results showed that D. rotundusabundance in northeastern Yucatan, Mexico was favored by extensive pastures as well as by landscape characteristics associated with intense forest fragmentation. However, the presence of some remnants of forest cover probably enhance the movements and persistence of this species. To reduce the negative impact of the vampire bat presence in these areas dedicated to livestock ranching activities, effective preventive vaccination campaigns could be an important strategy.

Albinism is defined as the complete absence of pigment in skin, hair, and eyes directly caused by a hereditary disorder in the production of melanin. This genetic abnormality is usually attributed to environmental factors such as low quality of habitat and inbreeding. In this note, we recorded a case of partial albinism in a raccoon (Procyon lotor) captured by poachers in the area known as Barranca de Matlacobatl, Municipality of Teocelo, Veracruz, Mexico. The specimen was recovered by the civil association Pro-Vida Silvestre Teocelotl and sheltered for a week under medical care. This is the second record in Mexico of a wild albino raccoon. Specifically, it was recorded particularly for a neotropical region of the center of the state of Veracruz, Mexico.

Background: Seed banks, an important element in the natural regeneration of plant communities, are regulated mostly by granivores along an altitudinal gradient. Question/Hypothesis: Pinus hartwegii forms transient and probably persistent seed banks along an altitudinal gradient. Seed removal will vary according to the removing agents, the altitude and the season. Species under study/Data description/Mathematical model: The formation of seed banks and the removal of Pinus hartwegii (Pinaceae) seeds along an altitudinal gradient were evaluated in different seasons using a linear model with two factorial variance analyses. Site and years of study: The study was conducted at the Cofre de Perote National Park, Veracruz, Mexico, over an altitudinal gradient (at 3,400, 3,600, 3,800 and 4,000 m a.s.l.) in July-September 2015 (rainy season), and January-March 2016 (dry season). Methods: In order to understand seed bank formation and identify the removal agents along an altitudinal gradient, two experiments were conducted with seeds from 10 trees at each altitudinal tier. Results: The results of the first experiment, after one year, demonstrated the formation of transient and probably persistent seed banks along an altitudinal gradient (P < 0.0001). The results of the second experiment showed significant variations in seed removal according to the removal agents and the seasons (P < 0.0001). Conclusions: Pinus hartwegii forms transient and probably persistent seed banks along an altitudinal gradient. Seed removal varies according to altitude and season.

Background: Foraging strategies may vary among guilds of granivores and impact the tree recruitment and biodiversity of plant communities. Hypothesis: The hypotheses were: during the night in areas with tree cover rodents will be the main seed removers, insects in open areas at night, and birds in all types of plant communities during the daytime. Studied species/Data description/Mathematical model: The seed removal by birds, rodents and insects was studied in a Mexican temperate forest. In order to detect differences in seed removal of Pinus patula, P. pseudostrobus, P. teocote and P. montezumae, a GLMM model with three way interaction (type of plant community, exclusion treatment and period) was carried out for each pine seed species where random variables were the variation among sites and months. Study site and years of study: This study was carried out in a Mexican temperate forest during February 2006 and January 2007. Methods: Through exclusion treatments we evaluated the seed removal of four pine species in three plant communities with two replicates (1 ha approximately) and two periods. Results: The three-way interaction was significant for all pine species (P < 0.001) (GLMM processes). The variance was greater among sites than between months. The main seed removers for all pine seed species, were: At night insects for subalpine grassland; during the daytime birds for all plant communities, and at night the rodents in pine forest, oak-alder forest and finally in the subalpine grassland. Conclusions: The rodents were the main seeds removers in areas with tree cover during the night, the insects in open areas at night, and birds in all plant communities during the daytime.