We review recent literature to address the question to what extent are nectarivorous and frugivorous mammals legitimate, efficient, and effective dis

We report the dispersal of Conostegia xalapensis (Melastomataceae) and Coussapoa oligocephala (Urticaceae) seeds by Underwood's long-tongued bat, a species considered to be a specialized nectar and pollen consumer. Informamos la dispersión de semillas de Conostegia xalapensis (Melastomataceae) y Coussapoa oligocephala (Urticaceae) por el murciélago de lengua larga de Underwood, una especie considerada como consumidora especializada en néctar y polen.

Under the hypothesis that bat diversity would be lower in the early stages of secondary succession and that species affected negatively by habitat modification would be more frequent in later successional stages, we evaluated how bats use 12 vegetation stands representing four stages of secondary succession, following disturbance caused by slash‐and‐burn agriculture and selective logging. We compared bat richness, abundance and diversity, and found that none of these variables was different among stages or rainy seasons. However, of the 10 most common bat species, two were significantly more abundant in stands at the early stages of secondary succession, while the opposite was true for three other species. Canopy cover mainly explains these patterns. Rainy season had no effect on the abundance of the common species. The results of this study indicate that although some frugivorous species were very abundant in the younger stands, the majority of the rare species were captured in older stands. The absence of rare and habitat‐specialized species from young successional stages close to primary forest suggests that, for effective bat conservation in landscapes modified by human activity, areas with original vegetation should be maintained to ensure the survivorship of sensitive‐to‐deforestation species.

Most studies on cactus recruitment have focused on the role of woody plants as seedling facilitators. Although the spatial association of cacti with objects had been described, the mechanisms underlying this association remain unknown. The aims of this study were to identify which mechanisms facilitate the establishment of a columnar cactus under the shade and protection of objects and to compare these mechanisms with those involved in plant–plant facilitation. Three split-split-plot field experiments were conducted to compare the effects of two microhabitats (inside rocky cavities and beneath plant canopies) on seed removal, germination, seedling survivorship and dry weight. Flat, open spaces were used as the control. For each microhabitat, the effect of seed or seedling protection and substrate limitation were explored; aboveground microclimate and some soil properties were also characterized. The permanence of superficial seeds was greater inside rocky cavities than beneath woody plant canopies or on flat, open areas. Germination was similar in cavities and beneath plant canopies, but significantly higher than on flat, open areas. Seedling survivorship was greater beneath plant canopies than inside cavities or on flat, open spaces. The mechanisms of plant facilitation are different from those of object facilitation. There are seed–seedling conflicts involved in the recruitment of P. leucocephalus: nurse plants favour mainly seedling survivorship by providing a suitable microenvironment, while nurse objects mainly favour seed permanence, by protecting them from predators.

Conversion of tropical rain forest to pasture and cropland often leads to a loss of local species. However, information on the role of some isolated elements of the fragmented landscape on maintaining biodiversity is lacking. This study, carried out in human-made pastures in Veracruz, Mexico, demonstrated the year-round presence of frugivorous bats in isolated trees inside pastures and in riparian corridors of vegetation among pastures. During a 1-year study (October 1995 through September 1996), we captured 652 bats belonging to 20 species, representing 56% of the total species recorded for the area. Higher abundance and diversity of bats were recorded for riparian sites than for isolated trees. Of the bats we captured, 82% were frugivorous, 15% insectivorous, 2% nectarivorous-frugivorous, and 2% sanguivorous. Bats visited isolated trees regardless of tree species or phenological state. Abundance decreased with distance from the nearest forest fragment. We discuss how riparian corridors and isol... Resumen La transformación de las selvas tropicales en pastizales ýreas de cultivo frecuentemente conduce a la pérdida de especies locales. Sin embargo, falta información sobre el papel de algunos elementos aislados del paisaje fragmentado en el mantenimiento de la biodiversidad. Este estudio registró la presencia de murciélagos frugívoros durante todo el año bajo árboles aislados y en la vegetación riparia remanente en pastizales antropogénicos en Veracruz, México. Durante un año de estudio (octubre 1995—septiembre 1996), capturamos 652 murciélagos de 20 especies, que representan el 56% de las especies registradas en el área. Los sitios en la vegetación riparia registraron mayor abundancia y diversidad que los sitios bajo árboles aislados. El 82% del total de murciélagos fueron frugívoros, 15% insectívoros, 2% nectarívoros-frugívoros y 2% sanguívoros. Los murciélagos visitaron los árboles aislados independientemente de la especie del árbol o de su estado fenológico. La abundancia disminuyó a mayor distanc...